Commit Graph

882 Commits

Author SHA1 Message Date
Ard Biesheuvel
0b767b16d7 efi/x86: Align efi_uga_draw_protocol typedef names to convention
The linux-efi subsystem uses typedefs with the _t suffix to declare
data structures that originate in the UEFI spec. Our type mangling
for mixed mode depends on this convention, so rename the UGA drawing
protocols to allow efi_call_proto() to be used with them in a
subsequent patch.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180720014726.24031-4-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-22 14:13:42 +02:00
Ard Biesheuvel
75c5a713ab efi/x86: Merge the setup_efi_pci32() and setup_efi_pci64() routines
After merging the 32-bit and 64-bit versions of the code that invokes
the PCI I/O protocol methods to preserve PCI ROM images in commit:

  2c3625cb9f ("efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() ...")

there are still separate code paths for 32-bit and 64-bit, where the only
difference is the size of a EFI_HANDLE. So let's parameterize a single
implementation for that difference only, and get rid of the two copies of
the code.

While at it, rename __setup_efi_pci() to preserve_pci_rom_image() to
better reflect its purpose.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180720014726.24031-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-22 14:13:42 +02:00
Ingo Molnar
90a2186b7d efi/x86: Clean up the eboot code
Various small cleanups:

 - Standardize printk messages:

     'alloc' => 'allocate'
     'mem'   => 'memory'

   also put variable names in printk messages between quotes.

 - Align mass-assignments vertically for better readability

 - Break multi-line function prototypes at the name where possible,
   not in the middle of the parameter list

 - Use a newline before return statements consistently.

 - Use curly braces in a balanced fashion.

 - Remove stray newlines.

No change in functionality.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711094040.12506-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-16 00:43:05 +02:00
Ard Biesheuvel
e296701800 efi/x86: Fix mixed mode reboot loop by removing pointless call to PciIo->Attributes()
Hans de Goede reported that his mixed EFI mode Bay Trail tablet
would not boot at all any more, but enter a reboot loop without
any logs printed by the kernel.

Unbreak 64-bit Linux/x86 on 32-bit UEFI:

When it was first introduced, the EFI stub code that copies the
contents of PCI option ROMs originally only intended to do so if
the EFI_PCI_IO_ATTRIBUTE_EMBEDDED_ROM attribute was *not* set.

The reason was that the UEFI spec permits PCI option ROM images
to be provided by the platform directly, rather than via the ROM
BAR, and in this case, the OS can only access them at runtime if
they are preserved at boot time by copying them from the areas
described by PciIo->RomImage and PciIo->RomSize.

However, it implemented this check erroneously, as can be seen in
commit:

  dd5fc854de ("EFI: Stash ROMs if they're not in the PCI BAR")

which introduced:

    if (!attributes & EFI_PCI_IO_ATTRIBUTE_EMBEDDED_ROM)
            continue;

and given that the numeric value of EFI_PCI_IO_ATTRIBUTE_EMBEDDED_ROM
is 0x4000, this condition never becomes true, and so the option ROMs
were copied unconditionally.

This was spotted and 'fixed' by commit:

  886d751a2e ("x86, efi: correct precedence of operators in setup_efi_pci")

but inadvertently inverted the logic at the same time, defeating
the purpose of the code, since it now only preserves option ROM
images that can be read from the ROM BAR as well.

Unsurprisingly, this broke some systems, and so the check was removed
entirely in the following commit:

  739701888f ("x86, efi: remove attribute check from setup_efi_pci")

It is debatable whether this check should have been included in the
first place, since the option ROM image provided to the UEFI driver by
the firmware may be different from the one that is actually present in
the card's flash ROM, and so whatever PciIo->RomImage points at should
be preferred regardless of whether the attribute is set.

As this was the only use of the attributes field, we can remove
the call to PciIo->Attributes() entirely, which is especially
nice because its prototype involves uint64_t type by-value
arguments which the EFI mixed mode has trouble dealing with.

Any mixed mode system with PCI is likely to be affected.

Tested-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180711090235.9327-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-11 13:15:21 +02:00
Baoquan He
747ff6265d x86/boot/KASLR: Skip specified number of 1GB huge pages when doing physical randomization (KASLR)
When KASLR is enabled then 1GB huge pages allocations might regress
sporadically.

To reproduce on a KVM guest with 4GB RAM:

- add the following options to the kernel command-line:

   'default_hugepagesz=1G hugepagesz=1G hugepages=1'

- boot the guest and check number of 1GB pages reserved:

    # grep HugePages_Total /proc/meminfo

- sporadically, every couple of bootups the output of this
  command shows that when booting with "nokaslr" HugePages_Total is always 1,
  while booting without "nokaslr" sometimes HugePages_Total is set as 0
  (that is, reserving the 1GB page failed).

Note that you may need to boot a few times to trigger the issue,
because it's somewhat non-deterministic.

The root cause is that kernel may be put into the only good 1GB huge page
in the [0x40000000, 0x7fffffff] physical range randomly.

Below is the dmesg output snippet from the KVM guest. We can see that only
[0x40000000, 0x7fffffff] region is good 1GB huge page,
[0x100000000, 0x13fffffff] will be touched by the memblock top-down allocation:

[...] e820: BIOS-provided physical RAM map:
[...] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
[...] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved
[...] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved
[...] BIOS-e820: [mem 0x0000000000100000-0x00000000bffdffff] usable
[...] BIOS-e820: [mem 0x00000000bffe0000-0x00000000bfffffff] reserved
[...] BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved
[...] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved
[...] BIOS-e820: [mem 0x0000000100000000-0x000000013fffffff] usable

Besides, on bare-metal machines with larger memory, one less 1GB huge page
might be available with KASLR enabled. That too is because the kernel
image might be randomized into those "good" 1GB huge pages.

To fix this, firstly parse the kernel command-line to get how many 1GB huge
pages are specified. Then try to skip the specified number of 1GB huge
pages when decide which memory region kernel can be randomized into.

Also change the name of handle_mem_memmap() as handle_mem_options()
since it handles not only 'mem=' and 'memmap=', but also 'hugepagesxxx' now.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: douly.fnst@cn.fujitsu.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: indou.takao@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: lcapitulino@redhat.com
Cc: yasu.isimatu@gmail.com
Link: http://lkml.kernel.org/r/20180625031656.12443-3-bhe@redhat.com
[ Rewrote the changelog, fixed style problems in the code. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-03 10:50:13 +02:00
Baoquan He
9b912485e0 x86/boot/KASLR: Add two new functions for 1GB huge pages handling
Introduce two new functions: parse_gb_huge_pages() and process_gb_huge_pages(),
which handle a conflict between KASLR and huge pages of 1GB.

These two functions will be used in the next patch:

- parse_gb_huge_pages() is used to parse kernel command-line to get
  how many 1GB huge pages have been specified. A static global
  variable 'max_gb_huge_pages' is added to store the number.

- process_gb_huge_pages() is used to skip as many 1GB huge pages
  as possible from the passed in memory region according to the
  specified number.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: douly.fnst@cn.fujitsu.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: indou.takao@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: lcapitulino@redhat.com
Cc: yasu.isimatu@gmail.com
Link: http://lkml.kernel.org/r/20180625031656.12443-2-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-07-03 10:50:12 +02:00
Ard Biesheuvel
2e6eb40ca5 efi/x86: Fix incorrect invocation of PciIo->Attributes()
The following commit:

  2c3625cb9f ("efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function")

... merged the two versions of __setup_efi_pciXX(), without taking into
account that the 32-bit version used a rather dodgy trick to pass an
immediate 0 constant as argument for a uint64_t parameter.

The issue is caused by the fact that on x86, UEFI protocol method calls
are redirected via struct efi_config::call(), which is a variadic function,
and so the compiler has to infer the types of the parameters from the
arguments rather than from the prototype.

As the 32-bit x86 calling convention passes arguments via the stack,
passing the unqualified constant 0 twice is the same as passing 0ULL,
which is why the 32-bit code in __setup_efi_pci32() contained the
following call:

  status = efi_early->call(pci->attributes, pci,
                           EfiPciIoAttributeOperationGet, 0, 0,
                           &attributes);

to invoke this UEFI protocol method:

  typedef
  EFI_STATUS
  (EFIAPI *EFI_PCI_IO_PROTOCOL_ATTRIBUTES) (
    IN  EFI_PCI_IO_PROTOCOL                     *This,
    IN  EFI_PCI_IO_PROTOCOL_ATTRIBUTE_OPERATION Operation,
    IN  UINT64                                  Attributes,
    OUT UINT64                                  *Result OPTIONAL
    );

After the merge, we inadvertently ended up with this version for both
32-bit and 64-bit builds, breaking the latter.

So replace the two zeroes with the explicitly typed constant 0ULL,
which works as expected on both 32-bit and 64-bit builds.

Wilfried tested the 64-bit build, and I checked the generated assembly
of a 32-bit build with and without this patch, and they are identical.

Reported-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Tested-by: Wilfried Klaebe <linux-kernel@lebenslange-mailadresse.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdegoede@redhat.com
Cc: linux-efi@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-24 09:05:58 +02:00
Linus Torvalds
f4e5b30d80 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 updates and fixes from Thomas Gleixner:

 - Fix the (late) fallout from the vector management rework causing
   hlist corruption and irq descriptor reference leaks caused by a
   missing sanity check.

   The straight forward fix triggered another long standing issue to
   surface. The pre rework code hid the issue due to being way slower,
   but now the chance that user space sees an EBUSY error return when
   updating irq affinities is way higher, though quite a bunch of
   userspace tools do not handle it properly despite the fact that EBUSY
   could be returned for at least 10 years.

   It turned out that the EBUSY return can be avoided completely by
   utilizing the existing delayed affinity update mechanism for irq
   remapped scenarios as well. That's a bit more error handling in the
   kernel, but avoids fruitless fingerpointing discussions with tool
   developers.

 - Decouple PHYSICAL_MASK from AMD SME as its going to be required for
   the upcoming Intel memory encryption support as well.

 - Handle legacy device ACPI detection properly for newer platforms

 - Fix the wrong argument ordering in the vector allocation tracepoint

 - Simplify the IDT setup code for the APIC=n case

 - Use the proper string helpers in the MTRR code

 - Remove a stale unused VDSO source file

 - Convert the microcode update lock to a raw spinlock as its used in
   atomic context.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Enable CMT and MBM on new Skylake stepping
  x86/apic/vector: Print APIC control bits in debugfs
  genirq/affinity: Defer affinity setting if irq chip is busy
  x86/platform/uv: Use apic_ack_irq()
  x86/ioapic: Use apic_ack_irq()
  irq_remapping: Use apic_ack_irq()
  x86/apic: Provide apic_ack_irq()
  genirq/migration: Avoid out of line call if pending is not set
  genirq/generic_pending: Do not lose pending affinity update
  x86/apic/vector: Prevent hlist corruption and leaks
  x86/vector: Fix the args of vector_alloc tracepoint
  x86/idt: Simplify the idt_setup_apic_and_irq_gates()
  x86/platform/uv: Remove extra parentheses
  x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME
  x86: Mark native_set_p4d() as __always_inline
  x86/microcode: Make the late update update_lock a raw lock for RT
  x86/mtrr: Convert to use strncpy_from_user() helper
  x86/mtrr: Convert to use match_string() helper
  x86/vdso: Remove unused file
  x86/i8237: Register device based on FADT legacy boot flag
2018-06-10 09:44:53 -07:00
Kirill A. Shutemov
94d49eb30e x86/mm: Decouple dynamic __PHYSICAL_MASK from AMD SME
AMD SME claims one bit from physical address to indicate whether the
page is encrypted or not. To achieve that we clear out the bit from
__PHYSICAL_MASK.

The capability to adjust __PHYSICAL_MASK is required beyond AMD SME.
For instance for upcoming Intel Multi-Key Total Memory Encryption.

Factor it out into a separate feature with own Kconfig handle.

It also helps with overhead of AMD SME. It saves more than 3k in .text
on defconfig + AMD_MEM_ENCRYPT:

	add/remove: 3/2 grow/shrink: 5/110 up/down: 189/-3753 (-3564)

We would need to return to this once we have infrastructure to patch
constants in code. That's good candidate for it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-mm@kvack.org
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180518113028.79825-1-kirill.shutemov@linux.intel.com
2018-06-06 13:38:01 +02:00
Linus Torvalds
5cef8c2a22 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:

 - Centaur CPU updates (David Wang)

 - AMD and other CPU topology enumeration improvements and fixes
   (Borislav Petkov, Thomas Gleixner, Suravee Suthikulpanit)

 - Continued 5-level paging work (Kirill A. Shutemov)

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Mark __pgtable_l5_enabled __initdata
  x86/mm: Mark p4d_offset() __always_inline
  x86/mm: Introduce the 'no5lvl' kernel parameter
  x86/mm: Stop pretending pgtable_l5_enabled is a variable
  x86/mm: Unify pgtable_l5_enabled usage in early boot code
  x86/boot/compressed/64: Fix trampoline page table address calculation
  x86/CPU: Move x86_cpuinfo::x86_max_cores assignment to detect_num_cpu_cores()
  x86/Centaur: Report correct CPU/cache topology
  x86/CPU: Move cpu_detect_cache_sizes() into init_intel_cacheinfo()
  x86/CPU: Make intel_num_cpu_cores() generic
  x86/CPU: Move cpu local function declarations to local header
  x86/CPU/AMD: Derive CPU topology from CPUID function 0xB when available
  x86/CPU: Modify detect_extended_topology() to return result
  x86/CPU/AMD: Calculate last level cache ID from number of sharing threads
  x86/CPU: Rename intel_cacheinfo.c to cacheinfo.c
  perf/events/amd/uncore: Fix amd_uncore_llc ID to use pre-defined cpu_llc_id
  x86/CPU/AMD: Have smp_num_siblings and cpu_llc_id always be present
  x86/Centaur: Initialize supported CPU features properly
2018-06-04 18:19:18 -07:00
Linus Torvalds
31a85cb35c Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:

 - decode x86 CPER data (Yazen Ghannam)

 - ignore unrealistically large option ROMs (Hans de Goede)

 - initialize UEFI secure boot state during Xen dom0 boot (Daniel Kiper)

 - additional minor tweaks and fixes.

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/capsule-loader: Don't output reset log when reset flags are not set
  efi/x86: Ignore unrealistically large option ROMs
  efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
  efi: Align efi_pci_io_protocol typedefs to type naming convention
  efi/libstub/tpm: Make function efi_retrieve_tpm2_eventlog_1_2() static
  efi: Decode IA32/X64 Context Info structure
  efi: Decode IA32/X64 MS Check structure
  efi: Decode additional IA32/X64 Bus Check fields
  efi: Decode IA32/X64 Cache, TLB, and Bus Check structures
  efi: Decode UEFI-defined IA32/X64 Error Structure GUIDs
  efi: Decode IA32/X64 Processor Error Info Structure
  efi: Decode IA32/X64 Processor Error Section
  efi: Fix IA32/X64 Processor Error Record definition
  efi/cper: Remove the INDENT_SP silliness
  x86/xen/efi: Initialize UEFI secure boot state during dom0 boot
2018-06-04 16:31:06 -07:00
Linus Torvalds
8a6bd2f40e Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "An unfortunately larger set of fixes, but a large portion is
  selftests:

   - Fix the missing clusterid initializaiton for x2apic cluster
     management which caused boot failures due to IPIs being sent to the
     wrong cluster

   - Drop TX_COMPAT when a 64bit executable is exec()'ed from a compat
     task

   - Wrap access to __supported_pte_mask in __startup_64() where clang
     compile fails due to a non PC relative access being generated.

   - Two fixes for 5 level paging fallout in the decompressor:

      - Handle GOT correctly for paging_prepare() and
        cleanup_trampoline()

      - Fix the page table handling in cleanup_trampoline() to avoid
        page table corruption.

   - Stop special casing protection key 0 as this is inconsistent with
     the manpage and also inconsistent with the allocation map handling.

   - Override the protection key wen moving away from PROT_EXEC to
     prevent inaccessible memory.

   - Fix and update the protection key selftests to address breakage and
     to cover the above issue

   - Add a MOV SS self test"

[ Part of the x86 fixes were in the earlier core pull due to dependencies ]

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm: Drop TS_COMPAT on 64-bit exec() syscall
  x86/apic/x2apic: Initialize cluster ID properly
  x86/boot/compressed/64: Fix moving page table out of trampoline memory
  x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline()
  x86/pkeys: Do not special case protection key 0
  x86/pkeys/selftests: Add a test for pkey 0
  x86/pkeys/selftests: Save off 'prot' for allocations
  x86/pkeys/selftests: Fix pointer math
  x86/pkeys: Override pkey when moving away from PROT_EXEC
  x86/pkeys/selftests: Fix pkey exhaustion test off-by-one
  x86/pkeys/selftests: Add PROT_EXEC test
  x86/pkeys/selftests: Factor out "instruction page"
  x86/pkeys/selftests: Allow faults on unknown keys
  x86/pkeys/selftests: Avoid printf-in-signal deadlocks
  x86/pkeys/selftests: Remove dead debugging code, fix dprint_in_signal
  x86/pkeys/selftests: Stop using assert()
  x86/pkeys/selftests: Give better unexpected fault error messages
  x86/selftests: Add mov_to_ss test
  x86/mpx/selftests: Adjust the self-test to fresh distros that export the MPX ABI
  x86/pkeys/selftests: Adjust the self-test to fresh distros that export the pkeys ABI
  ...
2018-05-20 11:28:32 -07:00
Kirill A. Shutemov
372fddf709 x86/mm: Introduce the 'no5lvl' kernel parameter
This kernel parameter allows to force kernel to use 4-level paging even
if hardware and kernel support 5-level paging.

The option may be useful to work around regressions related to 5-level
paging.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
ad3fe525b9 x86/mm: Unify pgtable_l5_enabled usage in early boot code
Usually pgtable_l5_enabled is defined using cpu_feature_enabled().
cpu_feature_enabled() is not available in early boot code. We use
several different preprocessor tricks to get around it. It's messy.

Unify them all.

If cpu_feature_enabled() is not yet available, USE_EARLY_PGTABLE_L5 can
be defined before all includes. It makes pgtable_l5_enabled rely on
__pgtable_l5_enabled variable instead. This approach fits all early
users.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
30bbf728ba x86/boot/compressed/64: Fix trampoline page table address calculation
Hugh noticied that we calculate the address of the trampoline page table
incorrectly in cleanup_trampoline().

TRAMPOLINE_32BIT_PGTABLE_OFFSET has to be divided by sizeof(unsigned long),
since trampoline_32bit is an 'unsigned long' pointer.

TRAMPOLINE_32BIT_PGTABLE_OFFSET is zero so the bug doesn't have a
visible effect.

Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: e9d0e6330e ("x86/boot/compressed/64: Prepare new top-level page table for trampoline")
Link: http://lkml.kernel.org/r/20180518103528.59260-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-19 11:56:57 +02:00
Kirill A. Shutemov
589bb62be3 x86/boot/compressed/64: Fix moving page table out of trampoline memory
cleanup_trampoline() relocates the top-level page table out of
trampoline memory. We use 'top_pgtable' as our new top-level page table.

But if the 'top_pgtable' would be referenced from C in a usual way,
the address of the table will be calculated relative to RIP.
After kernel gets relocated, the address will be in the middle of
decompression buffer and the page table may get overwritten.
This leads to a crash.

We calculate the address of other page tables relative to the relocation
address. It makes them safe. We should do the same for 'top_pgtable'.

Calculate the address of 'top_pgtable' in assembly and pass down to
cleanup_trampoline().

Move the page table to .pgtable section where the rest of page tables
are. The section is @nobits so we save 4k in kernel image.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: e9d0e6330e ("x86/boot/compressed/64: Prepare new top-level page table for trampoline")
Link: http://lkml.kernel.org/r/20180516080131.27913-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-16 12:15:13 +02:00
Kirill A. Shutemov
5c9b0b1c49 x86/boot/compressed/64: Set up GOT for paging_prepare() and cleanup_trampoline()
Eric and Hugh have reported instant reboot due to my recent changes in
decompression code.

The root cause is that I didn't realize that we need to adjust GOT to be
able to run C code that early.

The problem is only visible with an older toolchain. Binutils >= 2.24 is
able to eliminate GOT references by replacing them with RIP-relative
address loads:

  https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=commitdiff;h=80d873266dec

We need to adjust GOT two times:

 - before calling paging_prepare() using the initial load address
 - before calling C code from the relocated kernel

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 194a9749c7 ("x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G")
Link: http://lkml.kernel.org/r/20180516080131.27913-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-16 12:15:13 +02:00
Hans de Goede
1de3a1be8a efi/x86: Ignore unrealistically large option ROMs
setup_efi_pci() tries to save a copy of each PCI option ROM as this may
be necessary for the device driver for the PCI device to have access too.

On some systems the efi_pci_io_protocol's romimage and romsize fields
contain invalid data, which looks a bit like pointers pointing back into
other EFI code or data. Interpreting these pointers as romsize leads to
a very large value and if we then try to alloc this amount of memory to
save a copy the alloc call fails.

This leads to a "Failed to alloc mem for rom" error being printed on the
EFI console for each PCI device.

This commit avoids the printing of these errors, by checking romsize before
doing the alloc and if it is larger then the EFI spec limit of 16 MiB
silently ignore the ROM fields instead of trying to alloc mem and fail.

Tested-by: Hans de Goede <hdegoede@redhat.com>
[ardb: deduplicate 32/64 bit changes, use SZ_16M symbolic constant]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-16-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:49 +02:00
Ard Biesheuvel
2c3625cb9f efi/x86: Fold __setup_efi_pci32() and __setup_efi_pci64() into one function
As suggested by Lukas, use his efi_call_proto() and efi_table_attr()
macros to merge __setup_efi_pci32() and __setup_efi_pci64() into a
single function, removing the need to duplicate changes made in
subsequent patches across both.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-15-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:49 +02:00
Ard Biesheuvel
cb0ba79352 efi: Align efi_pci_io_protocol typedefs to type naming convention
In order to use the helper macros that perform type mangling with the
EFI PCI I/O protocol struct typedefs, align their Linux typenames with
the convention we use for definitionns that originate in the UEFI spec,
and add the trailing _t to each.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-14-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:57:48 +02:00
Ard Biesheuvel
0b3225ab94 efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode
Mixed mode allows a kernel built for x86_64 to interact with 32-bit
EFI firmware, but requires us to define all struct definitions carefully
when it comes to pointer sizes.

'struct efi_pci_io_protocol_32' currently uses a 'void *' for the
'romimage' field, which will be interpreted as a 64-bit field
on such kernels, potentially resulting in bogus memory references
and subsequent crashes.

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-14 08:56:29 +02:00
Dave Hansen
fb43d6cb91 x86/mm: Do not auto-massage page protections
A PTE is constructed from a physical address and a pgprotval_t.
__PAGE_KERNEL, for instance, is a pgprot_t and must be converted
into a pgprotval_t before it can be used to create a PTE.  This is
done implicitly within functions like pfn_pte() by massage_pgprot().

However, this makes it very challenging to set bits (and keep them
set) if your bit is being filtered out by massage_pgprot().

This moves the bit filtering out of pfn_pte() and friends.  For
users of PAGE_KERNEL*, filtering will be done automatically inside
those macros but for users of __PAGE_KERNEL*, they need to do their
own filtering now.

Note that we also just move pfn_pte/pmd/pud() over to check_pgprot()
instead of massage_pgprot().  This way, we still *look* for
unsupported bits and properly warn about them if we find them.  This
might happen if an unfiltered __PAGE_KERNEL* value was passed in,
for instance.

- printk format warning fix from: Arnd Bergmann <arnd@arndb.de>
- boot crash fix from:            Tom Lendacky <thomas.lendacky@amd.com>
- crash bisected by:              Mike Galbraith <efault@gmx.de>

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reported-and-fixed-by: Arnd Bergmann <arnd@arndb.de>
Fixed-by: Tom Lendacky <thomas.lendacky@amd.com>
Bisected-by: Mike Galbraith <efault@gmx.de>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180406205509.77E1D7F6@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-04-12 09:04:22 +02:00
Linus Torvalds
bc16d4052f Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main EFI changes in this cycle were:

   - Fix the apple-properties code (Andy Shevchenko)

   - Add WARN() on arm64 if UEFI Runtime Services corrupt the reserved
     x18 register (Ard Biesheuvel)

   - Use efi_switch_mm() on x86 instead of manipulating %cr3 directly
     (Sai Praneeth)

   - Fix early memremap leak in ESRT code (Ard Biesheuvel)

   - Switch to L"xxx" notation for wide string literals (Ard Biesheuvel)

   - ... plus misc other cleanups and bugfixes"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/efi: Use efi_switch_mm() rather than manually twiddling with %cr3
  x86/efi: Replace efi_pgd with efi_mm.pgd
  efi: Use string literals for efi_char16_t variable initializers
  efi/esrt: Fix handling of early ESRT table mapping
  efi: Use efi_mm in x86 as well as ARM
  efi: Make const array 'apple' static
  efi/apple-properties: Use memremap() instead of ioremap()
  efi: Reorder pr_notice() with add_device_randomness() call
  x86/efi: Replace GFP_ATOMIC with GFP_KERNEL in efi_query_variable_store()
  efi/arm64: Check whether x18 is preserved by runtime services calls
  efi/arm*: Stop printing addresses of virtual mappings
  efi/apple-properties: Remove redundant attribute initialization from unmarshal_key_value_pairs()
  efi/arm*: Only register page tables when they exist
2018-04-02 17:46:37 -07:00
Linus Torvalds
d22fff8141 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:

 - Extend the memmap= boot parameter syntax to allow the redeclaration
   and dropping of existing ranges, and to support all e820 range types
   (Jan H. Schönherr)

 - Improve the W+X boot time security checks to remove false positive
   warnings on Xen (Jan Beulich)

 - Support booting as Xen PVH guest (Juergen Gross)

 - Improved 5-level paging (LA57) support, in particular it's possible
   now to have a single kernel image for both 4-level and 5-level
   hardware (Kirill A. Shutemov)

 - AMD hardware RAM encryption support (SME/SEV) fixes (Tom Lendacky)

 - Preparatory commits for hardware-encrypted RAM support on Intel CPUs.
   (Kirill A. Shutemov)

 - Improved Intel-MID support (Andy Shevchenko)

 - Show EFI page tables in page_tables debug files (Andy Lutomirski)

 - ... plus misc fixes and smaller cleanups

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (56 commits)
  x86/cpu/tme: Fix spelling: "configuation" -> "configuration"
  x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
  x86/mm: Update comment in detect_tme() regarding x86_phys_bits
  x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic
  x86/mm: Remove pointless checks in vmalloc_fault
  x86/platform/intel-mid: Add special handling for ACPI HW reduced platforms
  ACPI, x86/boot: Introduce the ->reduced_hw_early_init() ACPI callback
  ACPI, x86/boot: Split out acpi_generic_reduce_hw_init() and export
  x86/pconfig: Provide defines and helper to run MKTME_KEY_PROG leaf
  x86/pconfig: Detect PCONFIG targets
  x86/tme: Detect if TME and MKTME is activated by BIOS
  x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G
  x86/boot/compressed/64: Use page table in trampoline memory
  x86/boot/compressed/64: Use stack from trampoline memory
  x86/boot/compressed/64: Make sure we have a 32-bit code segment
  x86/mm: Do not use paravirtualized calls in native_set_p4d()
  kdump, vmcoreinfo: Export pgtable_l5_enabled value
  x86/boot/compressed/64: Prepare new top-level page table for trampoline
  x86/boot/compressed/64: Set up trampoline memory
  x86/boot/compressed/64: Save and restore trampoline memory
  ...
2018-04-02 15:45:30 -07:00
Linus Torvalds
e68b4bad71 Merge branch 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 build updates from Ingo Molnar:
 "The biggest change is the forcing of asm-goto support on x86, which
  effectively increases the GCC minimum supported version to gcc-4.5 (on
  x86)"

* 'x86-build-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/build: Don't pass in -D__KERNEL__ multiple times
  x86: Remove FAST_FEATURE_TESTS
  x86: Force asm-goto
  x86/build: Drop superfluous ALIGN from the linker script
2018-04-02 14:37:03 -07:00
Cao jin
d6289f36aa x86/build: Don't pass in -D__KERNEL__ multiple times
Some .<target>.cmd files under arch/x86 are showing two instances of
-D__KERNEL__, like arch/x86/boot/ and arch/x86/realmode/rm/.

__KERNEL__ is already defined in KBUILD_CPPFLAGS in the top Makefile,
so it can be dropped safely.

Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kbuild@vger.kernel.org
Link: http://lkml.kernel.org/r/20180316084944.3997-1-caoj.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-31 08:02:07 +02:00
Tom Lendacky
07344b15a9 x86/boot: Fix SEV boot failure from change to __PHYSICAL_MASK_SHIFT
In arch/x86/boot/compressed/kaslr_64.c, CONFIG_AMD_MEM_ENCRYPT support was
initially #undef'd to support SME with minimal effort.  When support for
SEV was added, the #undef remained and some minimal support for setting the
encryption bit was added for building identity mapped pagetable entries.

Commit b83ce5ee91 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
changed __PHYSICAL_MASK_SHIFT from 46 to 52 in support of 5-level paging.
This change resulted in SEV guests failing to boot because the encryption
bit was no longer being automatically masked out.  The compressed boot
path now requires sme_me_mask to be defined in order for the pagetable
functions, such as pud_present(), to properly mask out the encryption bit
(currently bit 47) when evaluating pagetable entries.

Add an sme_me_mask variable in arch/x86/boot/compressed/mem_encrypt.S,
which is set when SEV is active, delete the #undef CONFIG_AMD_MEM_ENCRYPT
from arch/x86/boot/compressed/kaslr_64.c and use sme_me_mask when building
the identify mapped pagetable entries.

Fixes: b83ce5ee91 ("x86/mm/64: Make __PHYSICAL_MASK_SHIFT always 52")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20180327220711.8702.55842.stgit@tlendack-t1.amdoffice.net
2018-03-28 10:42:57 +02:00
Ingo Molnar
0bc91d4ba7 Linux 4.16-rc7
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Merge tag 'v4.16-rc7' into x86/mm, to fix up conflict

 Conflicts:
	arch/x86/mm/init_64.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-27 08:43:39 +02:00
Linus Torvalds
d2862360bf Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 and PTI fixes from Ingo Molnar:
 "Misc fixes:

   - fix EFI pagetables freeing

   - fix vsyscall pagetable setting on Xen PV guests

   - remove ancient CONFIG_X86_PPRO_FENCE=y - x86 is TSO again

   - fix two binutils (ld) development version related incompatibilities

   - clean up breakpoint handling

   - fix an x86 self-test"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/entry/64: Don't use IST entry for #BP stack
  x86/efi: Free efi_pgd with free_pages()
  x86/vsyscall/64: Use proper accessor to update P4D entry
  x86/cpu: Remove the CONFIG_X86_PPRO_FENCE=y quirk
  x86/boot/64: Verify alignment of the LOAD segment
  x86/build/64: Force the linker to use 2MB page size
  selftests/x86/ptrace_syscall: Fix for yet more glibc interference
2018-03-25 07:36:02 -10:00
H.J. Lu
c55b8550fa x86/boot/64: Verify alignment of the LOAD segment
Since the x86-64 kernel must be aligned to 2MB, refuse to boot the
kernel if the alignment of the LOAD segment isn't a multiple of 2MB.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/CAMe9rOrR7xSJgUfiCoZLuqWUwymRxXPoGBW38%2BpN%3D9g%2ByKNhZw@mail.gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-20 08:03:03 +01:00
Kirill A. Shutemov
194a9749c7 x86/boot/compressed/64: Handle 5-level paging boot if kernel is above 4G
This patch addresses a shortcoming in current boot process on machines
that supports 5-level paging.

If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.

But if the bootloader put the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.

This patch implements a trampoline in lower memory to handle this
situation.

We only need the memory for a very short time, until the main kernel
image sets up own page tables.

We go through the trampoline even if we don't have to: if we're already
in 5-level paging mode or if we don't need to switch to it. This way the
trampoline gets tested on every boot.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:25 +01:00
Kirill A. Shutemov
0a1756bd28 x86/boot/compressed/64: Use page table in trampoline memory
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling
paging. It works fine if kernel itself is loaded below 4G.

But if the bootloader put the kernel above 4G (i.e. in kexec() case),
we would lose control as soon as paging is disabled, because the code
becomes unreachable to the CPU.

To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.

Apart from the trampoline code itself we also need a place to store
top-level page table in lower memory as we don't have a way to load
64-bit values into CR3 in 32-bit mode. We only really need 8 bytes there
as we only use the very first entry of the page table. But we allocate a
whole page anyway.

This patch switches 32-bit code to use page table in trampoline memory.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:25 +01:00
Kirill A. Shutemov
f7ff53e470 x86/boot/compressed/64: Use stack from trampoline memory
As the first step on using trampoline memory, let's make 32-bit code use
stack there.

Separate stack is required to return back from trampoline and we cannot
user stack from 64-bit mode as it may be above 4G.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:24 +01:00
Kirill A. Shutemov
7beebaccd5 x86/boot/compressed/64: Make sure we have a 32-bit code segment
When kernel starts in 64-bit mode we inherit the GDT from the bootloader.
It may cause a problem if the GDT doesn't have a 32-bit code segment
where we expect it to be.

Load our own GDT with known segments.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180312100246.89175-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 11:49:24 +01:00
Ard Biesheuvel
36b649760e efi: Use string literals for efi_char16_t variable initializers
Now that we unambiguously build the entire kernel with -fshort-wchar,
it is no longer necessary to open code efi_char16_t[] initializers as
arrays of characters, and we can move to the L"xxx" notation instead.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180312084500.10764-6-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 10:05:02 +01:00
Kirill A. Shutemov
e9d0e6330e x86/boot/compressed/64: Prepare new top-level page table for trampoline
If trampoline code would need to switch between 4- and 5-level paging
modes, we have to use a page table in trampoline memory.

Having it in trampoline memory guarantees that it's below 4G and we can
point CR3 to it from 32-bit trampoline code.

We only use the page table if the desired paging mode doesn't match the
mode we are in. Otherwise the page table is unused and trampoline code
wouldn't touch CR3.

For 4- to 5-level paging transition, we set up current (4-level paging)
CR3 as the first and the only entry in a new top-level page table.

For 5- to 4-level paging transition, copy page table pointed by first
entry in the current top-level page table as our new top-level page
table.

If the page table is used by trampoline we would need to copy it to new
page table outside trampoline and update CR3 before restoring trampoline
memory.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-6-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:26 +01:00
Kirill A. Shutemov
32fcefa2bf x86/boot/compressed/64: Set up trampoline memory
This patch clears up trampoline memory and copies trampoline code in
place. It's not yet used though.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:25 +01:00
Kirill A. Shutemov
fb5268354d x86/boot/compressed/64: Save and restore trampoline memory
The memory area we found for trampoline shouldn't contain anything
useful. But let's preserve the data anyway. Just to be on safe side.

paging_prepare() would save the data into a buffer.

cleanup_trampoline() would restore it back once we are done with the
trampoline.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:25 +01:00
Kirill A. Shutemov
3548e131ec x86/boot/compressed/64: Find a place for 32-bit trampoline
If a bootloader enables 64-bit mode with 4-level paging, we might need to
switch over to 5-level paging. The switching requires the disabling of
paging, which works fine if kernel itself is loaded below 4G.

But if the bootloader puts the kernel above 4G (not sure if anybody does
this), we would lose control as soon as paging is disabled, because the
code becomes unreachable to the CPU.

To handle the situation, we need a trampoline in lower memory that would
take care of switching on 5-level paging.

This patch finds a spot in low memory for a trampoline.

The heuristic is based on code in reserve_bios_regions().

We find the end of low memory based on BIOS and EBDA start addresses.
The trampoline is put just before end of low memory. It's mimic approach
taken to allocate memory for realtime trampoline.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:37:23 +01:00
Kirill A. Shutemov
a403d79818 x86/boot/compressed/64: Describe the logic behind the LA57 check
The patch explains the LA57 check in more details.

Tested-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180226180451.86788-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 09:29:24 +01:00
Colin Ian King
f779ca740f efi: Make const array 'apple' static
Don't populate the const read-only array 'buf' on the stack but instead
make it static. Makes the object code smaller by 64 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   9264	      1	     16	   9281	   2441	arch/x86/boot/compressed/eboot.o

After:
   text	   data	    bss	    dec	    hex	filename
   9200	      1	     16	   9217	   2401	arch/x86/boot/compressed/eboot.o

(GCC version 7.2.0 x86_64)

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180308080020.22828-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-09 09:30:35 +01:00
Ingo Molnar
1ea4fe8497 Merge branch 'x86/boot' into x86/mm, to unify branches
Both x86/mm and x86/boot contain 5-level paging related patches,
unify them to have a single tree to work against.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:48:08 +01:00
Ingo Molnar
3f7df3efeb Linux 4.16-rc3
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAlqTdg8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG10wH/iSt+OKmBdUZSAYv
 ADvfifLynLgugFYNzuijj8/gVt6b0ZIB2/wSYfdPjDErLFogis6wjnxl0lf3sEMB
 g7Oy8SE+pPPQ7587lFkg6Pj53405b6BwCbSkg8PLlwepSGiu0JmGvUYmz753tIeP
 kRIIQk/KrLlxNFixhGWNfQ9k8PqJ0NCgcbj+mTxmFkfIw2FKnBtYz72LR7Eut3Mt
 PJFh4pLKsHKlcjvX8+SehDdLwlEBv/ohDP7S7gRyR+QX1aNZhZAXyHQ0C8/tw8h6
 DnRvlTWp9EGTFxp8bYie5xcWusIcfy1eAA8yiG2kH+Mx7kLa8cmU234bHhUiu9yT
 YJSLoI4=
 =XBoV
 -----END PGP SIGNATURE-----

Merge tag 'v4.16-rc3' into x86/mm, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-26 08:41:15 +01:00
Ingo Molnar
ed7158bae4 treewide/trivial: Remove ';;$' typo noise
On lkml suggestions were made to split up such trivial typo fixes into per subsystem
patches:

  --- a/arch/x86/boot/compressed/eboot.c
  +++ b/arch/x86/boot/compressed/eboot.c
  @@ -439,7 +439,7 @@ setup_uga32(void **uga_handle, unsigned long size, u32 *width, u32 *height)
          struct efi_uga_draw_protocol *uga = NULL, *first_uga;
          efi_guid_t uga_proto = EFI_UGA_PROTOCOL_GUID;
          unsigned long nr_ugas;
  -       u32 *handles = (u32 *)uga_handle;;
  +       u32 *handles = (u32 *)uga_handle;
          efi_status_t status = EFI_INVALID_PARAMETER;
          int i;

This patch is the result of the following script:

  $ sed -i 's/;;$/;/g' $(git grep -E ';;$'  | grep "\.[ch]:"  | grep -vwE 'for|ia64' | cut -d: -f1 | sort | uniq)

... followed by manual review to make sure it's all good.

Splitting this up is just crazy talk, let's get over with this and just do it.

Reported-by: Pavel Machek <pavel@ucw.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-22 10:59:33 +01:00
Kirill A. Shutemov
39b9552281 x86/mm: Optimize boot-time paging mode switching cost
By this point we have functioning boot-time switching between 4- and
5-level paging mode. But naive approach comes with cost.

Numbers below are for kernel build, allmodconfig, 5 times.

CONFIG_X86_5LEVEL=n:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17308719.892691      task-clock:u (msec)       #   26.772 CPUs utilized            ( +-  0.11% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,993,164      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,614,978,867,455      cycles:u                  #    2.520 GHz                      ( +-  0.01% )
39,371,534,575,126      stalled-cycles-frontend:u #   90.27% frontend cycles idle     ( +-  0.09% )
28,363,350,152,428      instructions:u            #    0.65  insn per cycle
                                                  #    1.39  stalled cycles per insn  ( +-  0.00% )
 6,316,784,066,413      branches:u                #  364.948 M/sec                    ( +-  0.00% )
   250,808,144,781      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )

     646.531974142 seconds time elapsed                                          ( +-  1.15% )

CONFIG_X86_5LEVEL=y:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17411536.780625      task-clock:u (msec)       #   26.426 CPUs utilized            ( +-  0.10% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,868,663      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,865,909,056,301      cycles:u                  #    2.519 GHz                      ( +-  0.01% )
39,740,130,365,581      stalled-cycles-frontend:u #   90.59% frontend cycles idle     ( +-  0.05% )
28,363,358,997,959      instructions:u            #    0.65  insn per cycle
                                                  #    1.40  stalled cycles per insn  ( +-  0.00% )
 6,316,784,937,460      branches:u                #  362.793 M/sec                    ( +-  0.00% )
   251,531,919,485      branch-misses:u           #    3.98% of all branches          ( +-  0.00% )

     658.886307752 seconds time elapsed                                          ( +-  0.92% )

The patch tries to fix the performance regression by using
cpu_feature_enabled(X86_FEATURE_LA57) instead of pgtable_l5_enabled in
all hot code paths. These will statically patch the target code for
additional performance.

CONFIG_X86_5LEVEL=y + the patch:

 Performance counter stats for 'sh -c make -j100 -B -k >/dev/null' (5 runs):

   17381990.268506      task-clock:u (msec)       #   26.907 CPUs utilized            ( +-  0.19% )
                 0      context-switches:u        #    0.000 K/sec
                 0      cpu-migrations:u          #    0.000 K/sec
       331,862,625      page-faults:u             #    0.019 M/sec                    ( +-  0.01% )
43,697,726,320,051      cycles:u                  #    2.514 GHz                      ( +-  0.03% )
39,480,408,690,401      stalled-cycles-frontend:u #   90.35% frontend cycles idle     ( +-  0.05% )
28,363,394,221,388      instructions:u            #    0.65  insn per cycle
                                                  #    1.39  stalled cycles per insn  ( +-  0.00% )
 6,316,794,985,573      branches:u                #  363.410 M/sec                    ( +-  0.00% )
   251,013,232,547      branch-misses:u           #    3.97% of all branches          ( +-  0.01% )

     645.991174661 seconds time elapsed                                          ( +-  1.19% )

Unfortunately, this approach doesn't help with text size:

  vmlinux.before .text size:	8190319
  vmlinux.after .text size:	8200623

The .text section is increased by about 4k. Not sure if we can do anything
about this.

Signed-off-by: Kirill A. Shuemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180216114948.68868-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-21 10:19:18 +01:00
Kirill A. Shutemov
6657fca06e x86/mm: Allow to boot without LA57 if CONFIG_X86_5LEVEL=y
All pieces of the puzzle are in place and we can now allow to boot with
CONFIG_X86_5LEVEL=y on a machine without LA57 support.

Kernel will detect that LA57 is missing and fold p4d at runtime.

Update the documentation and the Kconfig option description to reflect the
change.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-10-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:49 +01:00
Kirill A. Shutemov
b16e770bfa x86/mm: Initialize 'pgdir_shift' and 'ptrs_per_p4d' at boot-time
Switching between paging modes requires the folding of the p4d page table level
when we only have 4 paging levels, which means we need to adjust 'pgdir_shift'
and 'ptrs_per_p4d' during early boot according to paging mode.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:47 +01:00
Kirill A. Shutemov
4c2b4058ab x86/mm: Initialize 'pgtable_l5_enabled' at boot-time
'pgtable_l5_enabled' indicates which paging mode we are using. We need to
initialize it at boot-time according to machine capability.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214182542.69302-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-16 10:48:46 +01:00
Kirill A. Shutemov
c65e774fb3 x86/mm: Make PGDIR_SHIFT and PTRS_PER_P4D variable
For boot-time switching between 4- and 5-level paging we need to be able
to fold p4d page table level at runtime. It requires variable
PGDIR_SHIFT and PTRS_PER_P4D.

The change doesn't affect the kernel image size much:

   text	   data	    bss	    dec	    hex	filename
8628091	4734304	1368064	14730459	 e0c4db	vmlinux.before
8628393	4734340	1368064	14730797	 e0c62d	vmlinux.after

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-14 13:11:14 +01:00
Kirill A. Shutemov
e626e6bb0d x86/mm: Introduce 'pgtable_l5_enabled'
The new flag would indicate what paging mode we are in.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180214111656.88514-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-14 13:11:14 +01:00
Kirill A. Shutemov
4440977be1 x86/boot/compressed/64: Introduce paging_prepare()
Rename l5_paging_required() to paging_prepare() and change the
interface of the function.

This is a preparation for the next patch, which would make the function
also allocate memory for the 32-bit trampoline.

The function now returns a 128-bit structure. RAX would return
trampoline memory address (zero for now) and RDX would indicate if we
need to enable 5-level paging.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
[ Typo fixes and general clarification. ]
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180209142228.21231-3-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-11 12:36:18 +01:00
Kirill A. Shutemov
7cc4eb1bdd x86/boot/compressed/64: Rename pagetable.c to kaslr_64.c
The name of the file -- pagetable.c -- is misleading: it only contains
helpers used for KASLR in 64-bit mode.

Let's rename the file to reflect its content.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20180209142228.21231-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-02-11 12:36:18 +01:00
Linus Torvalds
ae0cb7be35 Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security
Pull tpm updates from James Morris:

 - reduce polling delays in tpm_tis

 - support retrieving TPM 2.0 Event Log through EFI before
   ExitBootServices

 - replace tpm-rng.c with a hwrng device managed by the driver for each
   TPM device

 - TPM resource manager synthesizes TPM_RC_COMMAND_CODE response instead
   of returning -EINVAL for unknown TPM commands. This makes user space
   more sound.

 - CLKRUN fixes:

    * Keep #CLKRUN disable through the entier TPM command/response flow

    * Check whether #CLKRUN is enabled before disabling and enabling it
      again because enabling it breaks PS/2 devices on a system where it
      is disabled

* 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  tpm: remove unused variables
  tpm: remove unused data fields from I2C and OF device ID tables
  tpm: only attempt to disable the LPC CLKRUN if is already enabled
  tpm: follow coding style for variable declaration in tpm_tis_core_init()
  tpm: delete the TPM_TIS_CLK_ENABLE flag
  tpm: Update MAINTAINERS for Jason Gunthorpe
  tpm: Keep CLKRUN enabled throughout the duration of transmit_cmd()
  tpm_tis: Move ilb_base_addr to tpm_tis_data
  tpm2-cmd: allow more attempts for selftest execution
  tpm: return a TPM_RC_COMMAND_CODE response if command is not implemented
  tpm: Move Linux RNG connection to hwrng
  tpm: use struct tpm_chip for tpm_chip_find_get()
  tpm: parse TPM event logs based on EFI table
  efi: call get_event_log before ExitBootServices
  tpm: add event log format version
  tpm: rename event log provider files
  tpm: move tpm_eventlog.h outside of drivers folder
  tpm: use tpm_msleep() value as max delay
  tpm: reduce tpm polling delay in tpm_tis_core
  tpm: move wait_for_tpm_stat() to respective driver files
2018-01-31 13:12:31 -08:00
Thiebaud Weksteen
33b6d03469 efi: call get_event_log before ExitBootServices
With TPM 2.0 specification, the event logs may only be accessible by
calling an EFI Boot Service. Modify the EFI stub to copy the log area to
a new Linux-specific EFI configuration table so it remains accessible
once booted.

When calling this service, it is possible to specify the expected format
of the logs: TPM 1.2 (SHA1) or TPM 2.0 ("Crypto Agile"). For now, only the
first format is retrieved.

Signed-off-by: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
2018-01-08 12:58:35 +02:00
Linus Torvalds
f39d7d78b7 Merge branch 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A couple of fixlets for x86:

   - Fix the ESPFIX double fault handling for 5-level pagetables

   - Fix the commandline parsing for 'apic=' on 32bit systems and update
     documentation

   - Make zombie stack traces reliable

   - Fix kexec with stack canary

   - Fix the delivery mode for APICs which was missed when the x86
     vector management was converted to single target delivery. Caused a
     regression due to the broken hardware which ignores affinity
     settings in lowest prio delivery mode.

   - Unbreak modules when AMD memory encryption is enabled

   - Remove an unused parameter of prepare_switch_to"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Switch all APICs to Fixed delivery mode
  x86/apic: Update the 'apic=' description of setting APIC driver
  x86/apic: Avoid wrong warning when parsing 'apic=' in X86-32 case
  x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR)
  x86: Remove unused parameter of prepare_switch_to
  x86/stacktrace: Make zombie stack traces reliable
  x86/mm: Unbreak modules that use the DMA API
  x86/build: Make isoimage work on Debian
  x86/espfix/64: Fix espfix double-fault handling on 5-level systems
2017-12-31 13:13:56 -08:00
Linus Torvalds
5aa90a8458 Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 page table isolation updates from Thomas Gleixner:
 "This is the final set of enabling page table isolation on x86:

   - Infrastructure patches for handling the extra page tables.

   - Patches which map the various bits and pieces which are required to
     get in and out of user space into the user space visible page
     tables.

   - The required changes to have CR3 switching in the entry/exit code.

   - Optimizations for the CR3 switching along with documentation how
     the ASID/PCID mechanism works.

   - Updates to dump pagetables to cover the user space page tables for
     W+X scans and extra debugfs files to analyze both the kernel and
     the user space visible page tables

  The whole functionality is compile time controlled via a config switch
  and can be turned on/off on the command line as well"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (32 commits)
  x86/ldt: Make the LDT mapping RO
  x86/mm/dump_pagetables: Allow dumping current pagetables
  x86/mm/dump_pagetables: Check user space page table for WX pages
  x86/mm/dump_pagetables: Add page table directory to the debugfs VFS hierarchy
  x86/mm/pti: Add Kconfig
  x86/dumpstack: Indicate in Oops whether PTI is configured and enabled
  x86/mm: Clarify the whole ASID/kernel PCID/user PCID naming
  x86/mm: Use INVPCID for __native_flush_tlb_single()
  x86/mm: Optimize RESTORE_CR3
  x86/mm: Use/Fix PCID to optimize user/kernel switches
  x86/mm: Abstract switching CR3
  x86/mm: Allow flushing for future ASID switches
  x86/pti: Map the vsyscall page if needed
  x86/pti: Put the LDT in its own PGD if PTI is on
  x86/mm/64: Make a full PGD-entry size hole in the memory map
  x86/events/intel/ds: Map debug buffers in cpu_entry_area
  x86/cpu_entry_area: Add debugstore entries to cpu_entry_area
  x86/mm/pti: Map ESPFIX into user space
  x86/mm/pti: Share entry text PMD
  x86/entry: Align entry text section to PMD boundary
  ...
2017-12-29 17:02:49 -08:00
Thomas Gleixner
aa8c6248f8 x86/mm/pti: Add infrastructure for page table isolation
Add the initial files for kernel page table isolation, with a minimal init
function and the boot time detection for this misfeature.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eduardo Valentin <eduval@amazon.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: aliguori@amazon.com
Cc: daniel.gruss@iaik.tugraz.at
Cc: hughd@google.com
Cc: keescook@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-23 21:12:59 +01:00
Matthew Wilcox
5f0e3fe6b1 x86/build: Make isoimage work on Debian
Debian does not ship a 'mkisofs' symlink to genisoimage.  All modern
distros ship genisoimage, so just use that directly.  That requires
renaming the 'genisoimage' function.  Also neaten up the 'for' loop
while I'm in here.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-16 16:23:31 +01:00
Changbin Du
f79ce87fa4 x86/build: Don't verify mtools configuration file for isoimage
If mtools.conf is not generated before, 'make isoimage' could complain:

  Kernel: arch/x86/boot/bzImage is ready  (#597)
    GENIMAGE arch/x86/boot/image.iso
   *** Missing file: arch/x86/boot/mtools.conf
  arch/x86/boot/Makefile:144: recipe for target 'isoimage' failed

mtools.conf is not used for isoimage generation, so do not check it.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 4366d57af1 ("x86/build: Factor out fdimage/isoimage generation commands to standalone script")
Link: http://lkml.kernel.org/r/1512053480-8083-1-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-11 18:55:38 +01:00
Kirill A. Shutemov
6d7e0ba2d2 x86/boot/compressed/64: Print error if 5-level paging is not supported
If the machine does not support the paging mode for which the kernel was
compiled, the boot process cannot continue.

It's not possible to let the kernel detect the mismatch as it does not even
reach the point where cpu features can be evaluted due to a triple fault in
the KASLR setup.

Instead of instantaneous silent reboot, emit an error message which gives
the user the information why the boot fails.

Fixes: 77ef56e4f0 ("x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y")
Reported-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: linux-mm@kvack.org
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20171204124059.63515-3-kirill.shutemov@linux.intel.com
2017-12-07 10:36:26 +01:00
Kirill A. Shutemov
08529078d8 x86/boot/compressed/64: Detect and handle 5-level paging at boot-time
Prerequisite for fixing the current problem of instantaneous reboots when a
5-level paging kernel is booted on 4-level paging hardware.

At the same time this change prepares the decompression code to boot-time
switching between 4- and 5-level paging.

[ tglx: Folded the GCC < 5 fix. ]

Fixes: 77ef56e4f0 ("x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: stable@vger.kernel.org
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: linux-mm@kvack.org
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20171204124059.63515-2-kirill.shutemov@linux.intel.com
2017-12-07 10:34:39 +01:00
Chao Fan
69550d41ff x86/boot/KASLR: Remove unused variable
There are two variables "rc" in mem_avoid_memmap. One at the top of the
function and another one inside the while() loop. Drop the outer one as it
is unused. Cleanup some whitespace damage while at it.

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gregkh@linuxfoundation.org
Cc: n-horiguchi@ah.jp.nec.com
Cc: keescook@chromium.org
Link: https://lkml.kernel.org/r/20171123090847.15293-1-fanc.fnst@cn.fujitsu.com
2017-11-23 20:17:59 +01:00
Linus Torvalds
eb4d47c8ce Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Two changes: Propagate const/__initconst, and use ARRAY_SIZE() some
  more"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/events/amd/iommu: Make iommu_pmu const and __initconst
  x86: Use ARRAY_SIZE
2017-11-13 16:58:05 -08:00
Linus Torvalds
6a9f70b0a5 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Three smaller changes:

   - clang fix

   - boot message beautification

   - unnecessary header inclusion removal"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Disable Clang warnings about GNU extensions
  x86/boot: Remove unnecessary #include <generated/utsrelease.h>
  x86/boot: Spell out "boot CPU" for BP
2017-11-13 16:32:30 -08:00
Changbin Du
7980f029d0 x86/build: Make the boot image generation less verbose
This change suppresses the 'dd' output and adds the '-quiet' parameter
to mkisofs tool. It also removes the 'Using ...' messages, as none of the
messages matter to the user normally.

"make V=1" can still be used for a more verbose build.

The new build messages are now a streamlined set of:

  $ make isoimage
  ...
  Kernel: arch/x86/boot/bzImage is ready  (#75)
    GENIMAGE arch/x86/boot/image.iso
  Kernel: arch/x86/boot/image.iso is ready

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1510207751-22166-1-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-09 07:34:57 +01:00
Tom Lendacky
1958b5fc40 x86/boot: Add early boot support when running with SEV active
Early in the boot process, add checks to determine if the kernel is
running with Secure Encrypted Virtualization (SEV) active.

Checking for SEV requires checking that the kernel is running under a
hypervisor (CPUID 0x00000001, bit 31), that the SEV feature is available
(CPUID 0x8000001f, bit 1) and then checking a non-interceptable SEV MSR
(0xc0010131, bit 0).

This check is required so that during early compressed kernel booting the
pagetables (both the boot pagetables and KASLR pagetables (if enabled) are
updated to include the encryption mask so that when the kernel is
decompressed into encrypted memory, it can boot properly.

After the kernel is decompressed and continues booting the same logic is
used to check if SEV is active and set a flag indicating so.  This allows
to distinguish between SME and SEV, each of which have unique differences
in how certain things are handled: e.g. DMA (always bounce buffered with
SEV) or EFI tables (always access decrypted with SME).

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kvm@vger.kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-13-brijesh.singh@amd.com
2017-11-07 15:35:58 +01:00
Changbin Du
d786f05175 x86/build: Add more generated files to the .gitignore file
Some of the files generated by the build process were not listed.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yamada.masahiro@socionext.com
Link: http://lkml.kernel.org/r/1509939179-7556-5-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 11:22:21 +01:00
Changbin Du
c306ba7b90 x86/build: Specify -input-charset=utf-8 for mkisofs
It avoids the following warning triggered by newer versions of mkisofs:

    -input-charset not specified, using utf-8 (detected in locale settings)

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yamada.masahiro@socionext.com
Link: http://lkml.kernel.org/r/1509939179-7556-4-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 11:22:20 +01:00
Changbin Du
8a7546a04e x86/build: Add new paths for isolinux.bin and ldlinux.c32
Recently I failed to build isoimage target, because the path of isolinux.bin
changed to /usr/xxx/ISOLINUX/isolinux.bin, as well as ldlinux.c32 which
changed to /usr/xxx/syslinux/modules/bios/ldlinux.c32.

This patch improves the file search logic:
  - Show a error message instead of silent fail.
  - Add above new paths.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: yamada.masahiro@socionext.com
Link: http://lkml.kernel.org/r/1509939179-7556-3-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 11:22:20 +01:00
Changbin Du
4366d57af1 x86/build: Factor out fdimage/isoimage generation commands to standalone script
The build messages for fdimage/isoimage generation are pretty unstructured,
just the raw shell command blocks are printed.

Emit shortened messages similar to existing kbuild messages, and move
the Makefile commands into a separate shell script - which is much
easier to handle.

This patch factors out the commands used for fdimage/isoimage generation
from arch/x86/boot/Makefile to a new script arch/x86/boot/genimage.sh.
Then it adds the new kbuild command 'genimage' which invokes the new script.
All fdimages/isoimage files are now generated by a call to 'genimage' with
different parameters.

Now 'make isoimage' becomes:

	...
	Kernel: arch/x86/boot/bzImage is ready  (#30)
	  GENIMAGE arch/x86/boot/image.iso
	Size of boot image is 4 sectors -> No emulation
	 15.37% done, estimate finish Sun Nov  5 23:36:57 2017
	 30.68% done, estimate finish Sun Nov  5 23:36:57 2017
	 46.04% done, estimate finish Sun Nov  5 23:36:57 2017
	 61.35% done, estimate finish Sun Nov  5 23:36:57 2017
	 76.69% done, estimate finish Sun Nov  5 23:36:57 2017
	 92.00% done, estimate finish Sun Nov  5 23:36:57 2017
	Total translation table size: 2048
	Total rockridge attributes bytes: 659
	Total directory bytes: 0
	Path table size(bytes): 10
	Max brk space used 0
	32608 extents written (63 MB)
	Kernel: arch/x86/boot/image.iso is ready

Before:

	Kernel: arch/x86/boot/bzImage is ready  (#63)
	rm -rf arch/x86/boot/isoimage
	mkdir arch/x86/boot/isoimage
	for i in lib lib64 share end ; do \
		if [ -f /usr/$i/syslinux/isolinux.bin ] ; then \
			cp /usr/$i/syslinux/isolinux.bin arch/x86/boot/isoimage ; \
			if [ -f /usr/$i/syslinux/ldlinux.c32 ]; then \
				cp /usr/$i/syslinux/ldlinux.c32 arch/x86/boot/isoimage ; \
			fi ; \
			break ; \
		fi ; \
		if [ $i = end ] ; then exit 1 ; fi ; \
	done
	...

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1509939179-7556-2-git-send-email-changbin.du@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-11-07 11:22:20 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Matthias Kaehlcke
6c3b56b197 x86/boot: Disable Clang warnings about GNU extensions
The kernel makes use of several GCC extensions, disable Clang warnings
about that in the boot code, as we already do for the rest of the kernel.

This suppresses the following warning when building with clang:

  ./include/linux/cgroup-defs.h:391:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]
        struct cgroup cgrp;

Reported-by: Nick Desaulniers <nick.desaulniers@gmail.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171030194351.122090-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-31 10:54:30 +01:00
Jérémy Lefaure
0cfe5b5fc0 x86: Use ARRAY_SIZE
Using the ARRAY_SIZE macro improves the readability of the code.

Found with Coccinelle with the following semantic patch:
@r depends on (org || report)@
type T;
T[] E;
position p;
@@
(
 (sizeof(E)@p /sizeof(*E))
|
 (sizeof(E)@p /sizeof(E[...]))
|
 (sizeof(E)@p /sizeof(T))
)

Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-video@atrey.karlin.mff.cuni.cz
Cc: Martin Mares <mj@ucw.cz>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: https://lkml.kernel.org/r/20171001193101.8898-13-jeremy.lefaure@lse.epita.fr
2017-10-19 16:15:47 +02:00
Masahiro Yamada
dc0fdf7d2b x86/boot: Remove unnecessary #include <generated/utsrelease.h>
The <generated/utsrelease.h> defines UTS_RELEASE, but I do not
see any reference to it in arch/x86/boot/header.S.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1505921232-8960-1-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-10-11 16:46:23 +02:00
Linus Torvalds
f92e3da18b Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Transparently fall back to other poweroff method(s) if EFI poweroff
     fails (and returns)

   - Use separate PE/COFF section headers for the RX and RW parts of the
     ARM stub loader so that the firmware can use strict mapping
     permissions

   - Add support for requesting the firmware to wipe RAM at warm reboot

   - Increase the size of the random seed obtained from UEFI so CRNG
     fast init can complete earlier

   - Update the EFI framebuffer address if it points to a BAR that gets
     moved by the PCI resource allocation code

   - Enable "reset attack mitigation" of TPM environments: this is
     enabled if the kernel is configured with
     CONFIG_RESET_ATTACK_MITIGATION=y.

   - Clang related fixes

   - Misc cleanups, constification, refactoring, etc"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/bgrt: Use efi_mem_type()
  efi: Move efi_mem_type() to common code
  efi/reboot: Make function pointer orig_pm_power_off static
  efi/random: Increase size of firmware supplied randomness
  efi/libstub: Enable reset attack mitigation
  firmware/efi/esrt: Constify attribute_group structures
  firmware/efi: Constify attribute_group structures
  firmware/dcdbas: Constify attribute_group structures
  arm/efi: Split zImage code and data into separate PE/COFF sections
  arm/efi: Replace open coded constants with symbolic ones
  arm/efi: Remove pointless dummy .reloc section
  arm/efi: Remove forbidden values from the PE/COFF header
  drivers/fbdev/efifb: Allow BAR to be moved instead of claiming it
  efi/reboot: Fall back to original power-off method if EFI_RESET_SHUTDOWN returns
  efi/arm/arm64: Add missing assignment of efi.config_table
  efi/libstub/arm64: Set -fpie when building the EFI stub
  efi/libstub/arm64: Force 'hidden' visibility for section markers
  efi/libstub/arm64: Use hidden attribute for struct screen_info reference
  efi/arm: Don't mark ACPI reclaim memory as MEMBLOCK_NOMAP
2017-09-07 09:42:35 -07:00
Linus Torvalds
24e700e291 Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 apic updates from Thomas Gleixner:
 "This update provides:

   - Cleanup of the IDT management including the removal of the extra
     tracing IDT. A first step to cleanup the vector management code.

   - The removal of the paravirt op adjust_exception_frame. This is a
     XEN specific issue, but merged through this branch to avoid nasty
     merge collisions

   - Prevent dmesg spam about the TSC DEADLINE bug, when the CPU has
     disabled the TSC DEADLINE timer in CPUID.

   - Adjust a debug message in the ioapic code to print out the
     information correctly"

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
  x86/idt: Fix the X86_TRAP_BP gate
  x86/xen: Get rid of paravirt op adjust_exception_frame
  x86/eisa: Add missing include
  x86/idt: Remove superfluous ALIGNment
  x86/apic: Silence "FW_BUG TSC_DEADLINE disabled due to Errata" on CPUs without the feature
  x86/idt: Remove the tracing IDT leftovers
  x86/idt: Hide set_intr_gate()
  x86/idt: Simplify alloc_intr_gate()
  x86/idt: Deinline setup functions
  x86/idt: Remove unused functions/inlines
  x86/idt: Move interrupt gate initialization to IDT code
  x86/idt: Move APIC gate initialization to tables
  x86/idt: Move regular trap init to tables
  x86/idt: Move IST stack based traps to table init
  x86/idt: Move debug stack init to table based
  x86/idt: Switch early trap init to IDT tables
  x86/idt: Prepare for table based init
  x86/idt: Move early IDT setup out of 32-bit asm
  x86/idt: Move early IDT handler setup to IDT code
  x86/idt: Consolidate IDT invalidation
  ...
2017-09-04 17:43:56 -07:00
Linus Torvalds
b1b6f83ac9 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm changes from Ingo Molnar:
 "PCID support, 5-level paging support, Secure Memory Encryption support

  The main changes in this cycle are support for three new, complex
  hardware features of x86 CPUs:

   - Add 5-level paging support, which is a new hardware feature on
     upcoming Intel CPUs allowing up to 128 PB of virtual address space
     and 4 PB of physical RAM space - a 512-fold increase over the old
     limits. (Supercomputers of the future forecasting hurricanes on an
     ever warming planet can certainly make good use of more RAM.)

     Many of the necessary changes went upstream in previous cycles,
     v4.14 is the first kernel that can enable 5-level paging.

     This feature is activated via CONFIG_X86_5LEVEL=y - disabled by
     default.

     (By Kirill A. Shutemov)

   - Add 'encrypted memory' support, which is a new hardware feature on
     upcoming AMD CPUs ('Secure Memory Encryption', SME) allowing system
     RAM to be encrypted and decrypted (mostly) transparently by the
     CPU, with a little help from the kernel to transition to/from
     encrypted RAM. Such RAM should be more secure against various
     attacks like RAM access via the memory bus and should make the
     radio signature of memory bus traffic harder to intercept (and
     decrypt) as well.

     This feature is activated via CONFIG_AMD_MEM_ENCRYPT=y - disabled
     by default.

     (By Tom Lendacky)

   - Enable PCID optimized TLB flushing on newer Intel CPUs: PCID is a
     hardware feature that attaches an address space tag to TLB entries
     and thus allows to skip TLB flushing in many cases, even if we
     switch mm's.

     (By Andy Lutomirski)

  All three of these features were in the works for a long time, and
  it's coincidence of the three independent development paths that they
  are all enabled in v4.14 at once"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (65 commits)
  x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)
  x86/mm: Use pr_cont() in dump_pagetable()
  x86/mm: Fix SME encryption stack ptr handling
  kvm/x86: Avoid clearing the C-bit in rsvd_bits()
  x86/CPU: Align CR3 defines
  x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
  acpi, x86/mm: Remove encryption mask from ACPI page protection type
  x86/mm, kexec: Fix memory corruption with SME on successive kexecs
  x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt
  x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y
  x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID
  x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y
  x86/mm: Allow userspace have mappings above 47-bit
  x86/mm: Prepare to expose larger address space to userspace
  x86/mpx: Do not allow MPX if we have mappings above 47-bit
  x86/mm: Rename tasksize_32bit/64bit to task_size_32bit/64bit()
  x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
  x86/mm/dump_pagetables: Fix printout of p4d level
  x86/mm/dump_pagetables: Generalize address normalization
  x86/boot: Fix memremap() related build failure
  ...
2017-09-04 12:21:28 -07:00
Linus Torvalds
45153920c7 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes are KASL related fixes and cleanups: in particular we
  now exclude certain physical memory ranges as KASLR randomization
  targets that have proven to be unreliable (early-)RAM on some firmware
  versions"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/KASLR: Work around firmware bugs by excluding EFI_BOOT_SERVICES_* and EFI_LOADER_* from KASLR's choice
  x86/boot/KASLR: Prefer mirrored memory regions for the kernel physical address
  efi: Introduce efi_early_memdesc_ptr to get pointer to memmap descriptor
  x86/boot/KASLR: Rename process_e820_entry() into process_mem_region()
  x86/boot/KASLR: Switch to pass struct mem_vector to process_e820_entry()
  x86/boot/KASLR: Wrap e820 entries walking code into new function process_e820_entries()
2017-09-04 10:51:02 -07:00
Linus Torvalds
b0c79f49c3 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:

 - Introduce the ORC unwinder, which can be enabled via
   CONFIG_ORC_UNWINDER=y.

   The ORC unwinder is a lightweight, Linux kernel specific debuginfo
   implementation, which aims to be DWARF done right for unwinding.
   Objtool is used to generate the ORC unwinder tables during build, so
   the data format is flexible and kernel internal: there's no
   dependency on debuginfo created by an external toolchain.

   The ORC unwinder is almost two orders of magnitude faster than the
   (out of tree) DWARF unwinder - which is important for perf call graph
   profiling. It is also significantly simpler and is coded defensively:
   there has not been a single ORC related kernel crash so far, even
   with early versions. (knock on wood!)

   But the main advantage is that enabling the ORC unwinder allows
   CONFIG_FRAME_POINTERS to be turned off - which speeds up the kernel
   measurably:

   With frame pointers disabled, GCC does not have to add frame pointer
   instrumentation code to every function in the kernel. The kernel's
   .text size decreases by about 3.2%, resulting in better cache
   utilization and fewer instructions executed, resulting in a broad
   kernel-wide speedup. Average speedup of system calls should be
   roughly in the 1-3% range - measurements by Mel Gorman [1] have shown
   a speedup of 5-10% for some function execution intense workloads.

   The main cost of the unwinder is that the unwinder data has to be
   stored in RAM: the memory cost is 2-4MB of RAM, depending on kernel
   config - which is a modest cost on modern x86 systems.

   Given how young the ORC unwinder code is it's not enabled by default
   - but given the performance advantages the plan is to eventually make
   it the default unwinder on x86.

   See Documentation/x86/orc-unwinder.txt for more details.

 - Remove lguest support: its intended role was that of a temporary
   proof of concept for virtualization, plus its removal will enable the
   reduction (removal) of the paravirt API as well, so Rusty agreed to
   its removal. (Juergen Gross)

 - Clean up and fix FSGS related functionality (Andy Lutomirski)

 - Clean up IO access APIs (Andy Shevchenko)

 - Enhance the symbol namespace (Jiri Slaby)

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
  objtool: Handle GCC stack pointer adjustment bug
  x86/entry/64: Use ENTRY() instead of ALIGN+GLOBAL for stub32_clone()
  x86/fpu/math-emu: Add ENDPROC to functions
  x86/boot/64: Extract efi_pe_entry() from startup_64()
  x86/boot/32: Extract efi_pe_entry() from startup_32()
  x86/lguest: Remove lguest support
  x86/paravirt/xen: Remove xen_patch()
  objtool: Fix objtool fallthrough detection with function padding
  x86/xen/64: Fix the reported SS and CS in SYSCALL
  objtool: Track DRAP separately from callee-saved registers
  objtool: Fix validate_branch() return codes
  x86: Clarify/fix no-op barriers for text_poke_bp()
  x86/switch_to/64: Rewrite FS/GS switching yet again to fix AMD CPUs
  selftests/x86/fsgsbase: Test selectors 1, 2, and 3
  x86/fsgsbase/64: Report FSBASE and GSBASE correctly in core dumps
  x86/fsgsbase/64: Fully initialize FS and GS state in start_thread_common
  x86/asm: Fix UNWIND_HINT_REGS macro for older binutils
  x86/asm/32: Fix regs_get_register() on segment registers
  x86/xen/64: Rearrange the SYSCALL entries
  x86/asm/32: Remove a bunch of '& 0xffff' from pt_regs segment reads
  ...
2017-09-04 09:52:57 -07:00
Naoya Horiguchi
0982adc746 x86/boot/KASLR: Work around firmware bugs by excluding EFI_BOOT_SERVICES_* and EFI_LOADER_* from KASLR's choice
There's a potential bug in how we select the KASLR kernel address n
the early boot code.

The KASLR boot code currently chooses the kernel image's physical memory
location from E820_TYPE_RAM regions by walking over all e820 entries.

E820_TYPE_RAM includes EFI_BOOT_SERVICES_CODE and EFI_BOOT_SERVICES_DATA
as well, so those regions can end up hosting the kernel image. According to
the UEFI spec, all memory regions marked as EfiBootServicesCode and
EfiBootServicesData are available as free memory after the first call
to ExitBootServices(). I.e. so such regions should be usable for the
kernel, per spec.

In real life however, we have workarounds for broken x86 firmware,
where we keep such regions reserved until SetVirtualAddressMap() is done.

See the following code in should_map_region():

	static bool should_map_region(efi_memory_desc_t *md)
	{
		...
		/*
		 * Map boot services regions as a workaround for buggy
		 * firmware that accesses them even when they shouldn't.
		 *
		 * See efi_{reserve,free}_boot_services().
		 */
		if (md->type =3D=3D EFI_BOOT_SERVICES_CODE ||
			md->type =3D=3D EFI_BOOT_SERVICES_DATA)
				return false;

This workaround suppressed a boot crash, but potential issues still
remain because no one prevents the regions from overlapping with kernel
image by KASLR.

So let's make sure that EFI_BOOT_SERVICES_{CODE|DATA} regions are never
chosen as kernel memory for the workaround to work fine.

Furthermore, EFI_LOADER_{CODE|DATA} regions are also excluded because
they can be used after ExitBootServices() as defined in EFI spec.

As a result, we choose kernel address only from EFI_CONVENTIONAL_MEMORY
which is the only memory type we know to be safely free.

Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Junichi Nomura <j-nomura@ce.jp.nec.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Link: http://lkml.kernel.org/r/20170828074444.GC23181@hori1.linux.bs1.fc.nec.co.jp
[ Rewrote/fixed/clarified the changelog and the in code comments. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-31 12:00:35 +02:00
Jan H. Schönherr
fb1cc2f916 x86/boot: Prevent faulty bootparams.screeninfo from causing harm
If a zero for the number of lines manages to slip through, scroll()
may underflow some offset calculations, causing accesses outside the
video memory.

Make the check in __putstr() more pessimistic to prevent that.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1503858223-14983-1-git-send-email-jschoenh@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:32:50 +02:00
Jan H. Schönherr
5746f0555d x86/boot: Provide more slack space during decompression
The current slack space is not enough for LZ4, which has a worst case
overhead of 0.4% for data that cannot be further compressed. With
an LZ4 compressed kernel with an embedded initrd, the output is likely
to overwrite the input.

Increase the slack space to avoid that.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1503842124-29718-1-git-send-email-jschoenh@amazon.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:32:50 +02:00
Jiri Slaby
9e085cefc6 x86/boot/64: Extract efi_pe_entry() from startup_64()
Similarly to the 32-bit code, efi_pe_entry body() is somehow squashed into
startup_64().

In the old days, we forced startup_64() to start at offset 0x200 and efi_pe_entry()
to start at 0x210. But this requirement was removed long time ago, in:

  99f857db88 ("x86, build: Dynamically find entry points in compressed startup code")

The way it is now makes the code less readable and illogical. Given
we can now safely extract the inlined efi_pe_entry() body from
startup_64() into a separate function, we do so.

We also annotate the function appropriatelly by ENTRY+ENDPROC.

ABI offsets are preserved:

  0000000000000000 T startup_32
  0000000000000200 T startup_64
  0000000000000390 T efi64_stub_entry

On the top-level, it looked like:

	.org 0x200
	ENTRY(startup_64)
	#ifdef CONFIG_EFI_STUB		; start of inlined
		jmp     preferred_addr
	GLOBAL(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
		leaq    preferred_addr(%rax), %rax
		jmp     *%rax
	preferred_addr:
	#endif				; end of inlined
		... ; a lot of assembly (startup_64)
	ENDPROC(startup_64)

And it is now converted into:

	.org 0x200
	ENTRY(startup_64)
		... ; a lot of assembly (startup_64)
	ENDPROC(startup_64)

	#ifdef CONFIG_EFI_STUB
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
		leaq    startup_64(%rax), %rax
		jmp     *%rax
	ENDPROC(efi_pe_entry)
	#endif

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170824073327.4129-2-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:23:29 +02:00
Jiri Slaby
f4dee0bb65 x86/boot/32: Extract efi_pe_entry() from startup_32()
The efi_pe_entry() body is somehow squashed into startup_32(). In the old days,
we forced startup_32() to start at offset 0x00 and efi_pe_entry() to start
at 0x10.

But this requirement was removed long time ago, in:

  99f857db88 ("x86, build: Dynamically find entry points in compressed startup code")

The way it is now makes the code less readable and illogical. Given
we can now safely extract the inlined efi_pe_entry() body from
startup_32() into a separate function, we do so and we separate it to two
functions as they are marked already: efi_pe_entry() + efi32_stub_entry().

We also annotate the functions appropriatelly by ENTRY+ENDPROC.

ABI offset is preserved:

  0000   128 FUNC    GLOBAL DEFAULT    6 startup_32
  0080    60 FUNC    GLOBAL DEFAULT    6 efi_pe_entry
  00bc    68 FUNC    GLOBAL DEFAULT    6 efi32_stub_entry

On the top-level, it looked like this:

	ENTRY(startup_32)
	#ifdef CONFIG_EFI_STUB		; start of inlined
		jmp     preferred_addr
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
	ENTRY(efi32_stub_entry)
		... ; a lot of assembly (efi32_stub_entry)
		leal    preferred_addr(%eax), %eax
		jmp     *%eax
	preferred_addr:
	#endif				; end of inlined
		... ; a lot of assembly (startup_32)
	ENDPROC(startup_32)

And it is now converted into:

	ENTRY(startup_32)
		... ; a lot of assembly (startup_32)
	ENDPROC(startup_32)

	#ifdef CONFIG_EFI_STUB
	ENTRY(efi_pe_entry)
		... ; a lot of assembly (efi_pe_entry)
	ENDPROC(efi_pe_entry)

	ENTRY(efi32_stub_entry)
		... ; a lot of assembly (efi32_stub_entry)
		leal    startup_32(%eax), %eax
		jmp     *%eax
	ENDPROC(efi32_stub_entry)
	#endif

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170824073327.4129-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 13:23:29 +02:00
Thomas Gleixner
64b163fab6 x86/idt: Unify gate_struct handling for 32/64-bit kernels
The first 32 bits of gate struct are the same for 32 and 64 bit kernels.

The 32-bit version uses desc_struct and no designated data structure,
so we need different accessors for 32 and 64 bit kernels.

Aside of that the macros which are necessary to build the 32-bit
gate descriptor are horrible to read.

Unify the gate structs and switch all code fiddling with it over.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064957.861974317@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:24 +02:00
Matthew Garrett
ccc829ba36 efi/libstub: Enable reset attack mitigation
If a machine is reset while secrets are present in RAM, it may be
possible for code executed after the reboot to extract those secrets
from untouched memory. The Trusted Computing Group specified a mechanism
for requesting that the firmware clear all RAM on reset before booting
another OS. This is done by setting the MemoryOverwriteRequestControl
variable at startup. If userspace can ensure that all secrets are
removed as part of a controlled shutdown, it can reset this variable to
0 before triggering a hardware reboot.

Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00
Ingo Molnar
413d63d71b Merge branch 'linus' into x86/mm to pick up fixes and to fix conflicts
Conflicts:
	arch/x86/kernel/head64.c
	arch/x86/mm/mmap.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:19:13 +02:00
Baoquan He
c05cd79750 x86/boot/KASLR: Prefer mirrored memory regions for the kernel physical address
Currently KASLR will parse all e820 entries of RAM type and add all
candidate positions into the slots array. After that we choose one slot
randomly as the new position which the kernel will be decompressed into
and run at.

On systems with EFI enabled, e820 memory regions are coming from EFI
memory regions by combining adjacent regions.

These EFI memory regions have various attributes, and the "mirrored"
attribute is one of them. The physical memory region whose descriptors
in EFI memory map has EFI_MEMORY_MORE_RELIABLE attribute (bit: 16) are
mirrored. The address range mirroring feature of the kernel arranges such
mirrored regions into normal zones and other regions into movable zones.

With the mirroring feature enabled, the code and data of the kernel can only
be located in the more reliable mirrored regions. However, the current KASLR
code doesn't check EFI memory entries, and could choose a new kernel position
in non-mirrored regions. This will break the intended functionality of the
address range mirroring feature.

To fix this, if EFI is detected, iterate EFI memory map and pick the mirrored
region to process for adding candidate of randomization slot. If EFI is disabled
or no mirrored region found, still process the e820 memory map.

Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: matt@codeblueprint.co.uk
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1502722464-20614-3-git-send-email-bhe@redhat.com
[ Rewrote most of the text. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:51:35 +02:00
Baoquan He
02e43c2dcd efi: Introduce efi_early_memdesc_ptr to get pointer to memmap descriptor
The existing map iteration helper for_each_efi_memory_desc_in_map can
only be used after the kernel initializes the EFI subsystem to set up
struct efi_memory_map.

Before that we also need iterate map descriptors which are stored in several
intermediate structures, like struct efi_boot_memmap for arch independent
usage and struct efi_info for x86 arch only.

Introduce efi_early_memdesc_ptr() to get pointer to a map descriptor, and
replace several places where that primitive is open coded.

Signed-off-by: Baoquan He <bhe@redhat.com>
[ Various improvements to the text. ]
Acked-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: ard.biesheuvel@linaro.org
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: keescook@chromium.org
Cc: linux-efi@vger.kernel.org
Cc: n-horiguchi@ah.jp.nec.com
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/20170816134651.GF21273@x1
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:50:57 +02:00
Ingo Molnar
2257e268b1 Merge branch 'linus' into x86/boot, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-17 10:50:48 +02:00
Matthias Kaehlcke
20c6c18904 x86/boot: Disable the address-of-packed-member compiler warning
The clang warning 'address-of-packed-member' is disabled for the general
kernel code, also disable it for the x86 boot code.

This suppresses a bunch of warnings like this when building with clang:

./arch/x86/include/asm/processor.h:535:30: warning: taking address of
  packed member 'sp0' of class or structure 'x86_hw_tss' may result in an
  unaligned pointer value [-Waddress-of-packed-member]
    return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
                                ^~~~~~~~~~~~~~~~~~~
./arch/x86/include/asm/percpu.h:391:59: note: expanded from macro
  'this_cpu_read_stable'
    #define this_cpu_read_stable(var)       percpu_stable_op("mov", var)
                                                                    ^~~
./arch/x86/include/asm/percpu.h:228:16: note: expanded from macro
  'percpu_stable_op'
    : "p" (&(var)));
             ^~~

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Cc: Doug Anderson <dianders@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170725215053.135586-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-28 08:39:08 +02:00
Michael Davidson
18d5e6c34a x86/boot: #undef memcpy() et al in string.c
undef memcpy() and friends in boot/string.c so that the functions
defined here will have the correct names, otherwise we end up
up trying to redefine __builtin_memcpy() etc.

Surprisingly, GCC allows this (and, helpfully, discards the
__builtin_ prefix from the function name when compiling it),
but clang does not.

Adding these #undef's appears to preserve what I assume was
the original intent of the code.

Signed-off-by: Michael Davidson <md@google.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Bernhard.Rosenkranzer@linaro.org
Cc: Greg Hackmann <ghackmann@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170724235155.79255-1-mka@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-25 11:13:55 +02:00
Arnd Bergmann
d460131dd5 x86/build: Silence the build with "make -s"
Every kernel build on x86 will result in some output:

  Setup is 13084 bytes (padded to 13312 bytes).
  System is 4833 kB
  CRC 6d35fa35
  Kernel: arch/x86/boot/bzImage is ready  (#2)

This shuts it up, so that 'make -s' is truely silent as long as
everything works. Building without '-s' should produce unchanged
output.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170719125310.2487451-6-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-20 10:46:24 +02:00
Tom Lendacky
21729f81ce x86/mm: Provide general kernel support for memory encryption
Changes to the existing page table macros will allow the SME support to
be enabled in a simple fashion with minimal changes to files that use these
macros.  Since the memory encryption mask will now be part of the regular
pagetable macros, we introduce two new macros (_PAGE_TABLE_NOENC and
_KERNPG_TABLE_NOENC) to allow for early pagetable creation/initialization
without the encryption mask before SME becomes active.  Two new pgprot()
macros are defined to allow setting or clearing the page encryption mask.

The FIXMAP_PAGE_NOCACHE define is introduced for use with MMIO.  SME does
not support encryption for MMIO areas so this define removes the encryption
mask from the page attribute.

Two new macros are introduced (__sme_pa() / __sme_pa_nodebug()) to allow
creating a physical address with the encryption mask.  These are used when
working with the cr3 register so that the PGD can be encrypted. The current
__va() macro is updated so that the virtual address is generated based off
of the physical address without the encryption mask thus allowing the same
virtual address to be generated regardless of whether encryption is enabled
for that physical location or not.

Also, an early initialization function is added for SME.  If SME is active,
this function:

 - Updates the early_pmd_flags so that early page faults create mappings
   with the encryption mask.

 - Updates the __supported_pte_mask to include the encryption mask.

 - Updates the protection_map entries to include the encryption mask so
   that user-space allocations will automatically have the encryption mask
   applied.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/b36e952c4c39767ae7f0a41cf5345adf27438480.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:00 +02:00
Baoquan He
27aac20574 x86/boot/KASLR: Rename process_e820_entry() into process_mem_region()
Now process_e820_entry() is not limited to e820 entry processing, rename
it to process_mem_region(). And adjust the code comment accordingly.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-4-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:12 +02:00
Baoquan He
87891b01b5 x86/boot/KASLR: Switch to pass struct mem_vector to process_e820_entry()
This makes process_e820_entry() be able to process any kind of memory
region.

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:11 +02:00
Baoquan He
f62995c92a x86/boot/KASLR: Wrap e820 entries walking code into new function process_e820_entries()
The original function process_e820_entry() only takes care of each
e820 entry passed.

And move the E820_TYPE_RAM checking logic into process_e820_entries().

And remove the redundent local variable 'addr' definition in
find_random_phys_addr().

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: fanc.fnst@cn.fujitsu.com
Cc: izumi.taku@jp.fujitsu.com
Cc: matt@codeblueprint.co.uk
Cc: thgarnie@google.com
Link: http://lkml.kernel.org/r/1499603862-11516-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:11:11 +02:00
Daniel Micay
6974f0c455 include/linux/string.h: add the option of fortified string.h functions
This adds support for compiling with a rough equivalent to the glibc
_FORTIFY_SOURCE=1 feature, providing compile-time and runtime buffer
overflow checks for string.h functions when the compiler determines the
size of the source or destination buffer at compile-time.  Unlike glibc,
it covers buffer reads in addition to writes.

GNU C __builtin_*_chk intrinsics are avoided because they would force a
much more complex implementation.  They aren't designed to detect read
overflows and offer no real benefit when using an implementation based
on inline checks.  Inline checks don't add up to much code size and
allow full use of the regular string intrinsics while avoiding the need
for a bunch of _chk functions and per-arch assembly to avoid wrapper
overhead.

This detects various overflows at compile-time in various drivers and
some non-x86 core kernel code.  There will likely be issues caught in
regular use at runtime too.

Future improvements left out of initial implementation for simplicity,
as it's all quite optional and can be done incrementally:

* Some of the fortified string functions (strncpy, strcat), don't yet
  place a limit on reads from the source based on __builtin_object_size of
  the source buffer.

* Extending coverage to more string functions like strlcat.

* It should be possible to optionally use __builtin_object_size(x, 1) for
  some functions (C strings) to detect intra-object overflows (like
  glibc's _FORTIFY_SOURCE=2), but for now this takes the conservative
  approach to avoid likely compatibility issues.

* The compile-time checks should be made available via a separate config
  option which can be enabled by default (or always enabled) once enough
  time has passed to get the issues it catches fixed.

Kees said:
 "This is great to have. While it was out-of-tree code, it would have
  blocked at least CVE-2016-3858 from being exploitable (improper size
  argument to strlcpy()). I've sent a number of fixes for
  out-of-bounds-reads that this detected upstream already"

[arnd@arndb.de: x86: fix fortified memcpy]
  Link: http://lkml.kernel.org/r/20170627150047.660360-1-arnd@arndb.de
[keescook@chromium.org: avoid panic() in favor of BUG()]
  Link: http://lkml.kernel.org/r/20170626235122.GA25261@beast
[keescook@chromium.org: move from -mm, add ARCH_HAS_FORTIFY_SOURCE, tweak Kconfig help]
Link: http://lkml.kernel.org/r/20170526095404.20439-1-danielmicay@gmail.com
Link: http://lkml.kernel.org/r/1497903987-21002-8-git-send-email-keescook@chromium.org
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:03 -07:00
Linus Torvalds
7a69f9c60b Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued work to add support for 5-level paging provided by future
     Intel CPUs. In particular we switch the x86 GUP code to the generic
     implementation. (Kirill A. Shutemov)

   - Continued work to add PCID CPU support to native kernels as well.
     In this round most of the focus is on reworking/refreshing the TLB
     flush infrastructure for the upcoming PCID changes. (Andy
     Lutomirski)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  x86/mm: Delete a big outdated comment about TLB flushing
  x86/mm: Don't reenter flush_tlb_func_common()
  x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
  x86/ftrace: Exclude functions in head64.c from function-tracing
  x86/mmap, ASLR: Do not treat unlimited-stack tasks as legacy mmap
  x86/mm: Remove reset_lazy_tlbstate()
  x86/ldt: Simplify the LDT switching logic
  x86/boot/64: Put __startup_64() into .head.text
  x86/mm: Add support for 5-level paging for KASLR
  x86/mm: Make kernel_physical_mapping_init() support 5-level paging
  x86/mm: Add sync_global_pgds() for configuration with 5-level paging
  x86/boot/64: Add support of additional page table level during early boot
  x86/boot/64: Rename init_level4_pgt and early_level4_pgt
  x86/boot/64: Rewrite startup_64() in C
  x86/boot/compressed: Enable 5-level paging during decompression stage
  x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
  x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
  x86/boot/efi: Cleanup initialization of GDT entries
  x86/asm: Fix comment in return_from_SYSCALL_64()
  x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation
  ...
2017-07-03 14:45:09 -07:00
Linus Torvalds
6553698be0 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "Two small cleanups"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/paravirt: Remove unnecessary return from void function
  x86/boot: Add missing strchr() declaration
2017-07-03 13:42:17 -07:00
Linus Torvalds
25e09ca524 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes in this cycle were KASLR improvements for rare
  environments with special boot options, by Baoquan He. Also misc
  smaller changes/cleanups"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/debug: Extend the lower bound of crash kernel low reservations
  x86/boot: Remove unused copy_*_gs() functions
  x86/KASLR: Use the right memcpy() implementation
  Documentation/kernel-parameters.txt: Update 'memmap=' boot option description
  x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options
  x86/KASLR: Parse all 'memmap=' boot option entries
2017-07-03 13:40:38 -07:00
Kirill A. Shutemov
a24261d70e x86/KASLR: Fix detection 32/64 bit bootloaders for 5-level paging
KASLR uses hack to detect whether we booted via startup_32() or
startup_64(): it checks what is loaded into cr3 and compares it to
_pgtables. _pgtables is the array of page tables where early code
allocates page table from.

KASLR expects cr3 to point to _pgtables if we booted via startup_32(), but
that's not true if we booted with 5-level paging enabled. In this case top
level page table is allocated separately and only the first p4d page table
is allocated from the array.

Let's modify the check to cover both 4- and 5-level paging cases.

The patch also renames 'level4p' to 'top_level_pgt' as it now can hold
page table for 4th or 5th level, depending on configuration.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170628121730.43079-1-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:56:53 +02:00
Baoquan He
8eabf42ae5 x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug
Kernel text KASLR is separated into physical address and virtual
address randomization. And for virtual address randomization, we
only randomiza to get an offset between 16M and KERNEL_IMAGE_SIZE.
So the initial value of 'virt_addr' should be LOAD_PHYSICAL_ADDR,
but not the original kernel loading address 'output'.

The bug will cause kernel boot failure if kernel is loaded at a different
position than the address, 16M, which is decided at compiled time.
Kexec/kdump is such practical case.

To fix it, just assign LOAD_PHYSICAL_ADDR to virt_addr as initial
value.

Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8391c73 ("x86/KASLR: Randomize virtual address separately")
Link: http://lkml.kernel.org/r/1498567146-11990-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:53:14 +02:00
Baoquan He
b892cb873c x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization
For kernel text KASLR, the virtual address is confined to area of 1G,
[0xffffffff80000000, 0xffffffffc0000000). For the implemenataion of
virtual address randomization, we only randomize to get an offset
between 16M and 1G, then add this offset to the starting address,
0xffffffff80000000. Here 16M is the offset which is decided at linking
stage. So the amount of the local variable 'virt_addr' which respresents
the offset plus the kernel output size can not exceed KERNEL_IMAGE_SIZE.

Add a debug check for the offset. If out of bounds, print error
message and hang there.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1498567146-11990-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 08:53:14 +02:00
Tommy Nguyen
6ec829a9d1 x86/boot: Add missing strchr() declaration
The Sparse static analyzer emits this warning:

    symbol 'strchr' was not declared. Should it be static?

This patch adds the appropriate extern declaration to string.h
to fix the warning.

Signed-off-by: Tommy Nguyen <remyabel@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170623143601.GA20743@NoChina
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-24 08:53:33 +02:00
Kirill A. Shutemov
34bbb0009f x86/boot/compressed: Enable 5-level paging during decompression stage
We need to cover two basic cases: when bootloader left us in 32-bit mode
and when bootloader enabled long mode.

The patch implements unified codepath to enabled 5-level paging for both
cases. It means case when we start in 32-bit mode, we first enable long
mode with 4-level and then switch over to 5-level paging.

Switching from 4-level to 5-level paging is not trivial. We cannot do it
directly. Setting LA57 in long mode would trigger #GP. So we need to
switch off long mode first and the then re-enable with 5-level paging.

NOTE: The need of switching off long mode means we are in trouble if
bootloader put us above 4G boundary. If bootloader wants to boot 5-level
paging kernel, it has to put kernel below 4G or enable 5-level paging on
it's own, so we could avoid the step.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-7-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:53 +02:00
Kirill A. Shutemov
919a02d128 x86/boot/efi: Define __KERNEL32_CS GDT on 64-bit configurations
We would need to switch temporarily to compatibility mode during booting
with 5-level paging enabled. It would require 32-bit code segment
descriptor.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-6-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:53 +02:00
Kirill A. Shutemov
4c94117c7f x86/boot/efi: Fix __KERNEL_CS definition of GDT entry on 64-bit configurations
Define __KERNEL_CS GDT entry as long mode (.L=1, .D=0) on 64-bit
configurations.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-5-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:52 +02:00
Kirill A. Shutemov
f8fceacbd1 x86/boot/efi: Cleanup initialization of GDT entries
This is preparation for following patches without changing semantics of the
code.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170606113133.22974-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:56:51 +02:00
Andy Lutomirski
6c690ee103 x86/mm: Split read_cr3() into read_cr3_pa() and __read_cr3()
The kernel has several code paths that read CR3.  Most of them assume that
CR3 contains the PGD's physical address, whereas some of them awkwardly
use PHYSICAL_PAGE_MASK to mask off low bits.

Add explicit mask macros for CR3 and convert all of the CR3 readers.
This will keep them from breaking when PCID is enabled.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: xen-devel <xen-devel@lists.xen.org>
Link: http://lkml.kernel.org/r/883f8fb121f4616c1c1427ad87350bb2f5ffeca1.1497288170.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-13 08:48:09 +02:00
Jiri Slaby
28be1b454c x86/boot: Remove unused copy_*_gs() functions
copy_from_gs() and copy_to_gs() are unused in the boot code. They have
actually never been used -- they were always commented out since their
addition in 2007:

  5be8656615 ("String-handling functions for the new x86 setup code.")

So remove them -- they can be restored from history if needed.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170531081243.5709-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-05 09:35:16 +02:00
Arnd Bergmann
5b8b9cf76a x86/KASLR: Use the right memcpy() implementation
The decompressor has its own implementation of the string functions,
but has to include the right header to get those, while implicitly
including linux/string.h may result in a link error:

  arch/x86/boot/compressed/kaslr.o: In function `choose_random_location':
  kaslr.c:(.text+0xf51): undefined reference to `_mmx_memcpy'

This has appeared now as KASLR started using memcpy(), via:

	d52e7d5a95 ("x86/KASLR: Parse all 'memmap=' boot option entries")

Other files in the decompressor already do the same thing.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170530091446.1000183-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-31 07:59:45 +02:00
Baoquan He
4cdba14f84 x86/KASLR: Handle the memory limit specified by the 'memmap=' and 'mem=' boot options
The 'mem=' boot option limits the max address a system can use - any memory
region above the limit will be removed.

Furthermore, the 'memmap=nn[KMG]' variant (with no offset specified) has the same
behaviour as 'mem='.

KASLR needs to consider this when choosing the random position for
decompressing the kernel. Do it.

Tested-by: Masayoshi Mizuma <m.mizuma@jp.fujitsu.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Link: http://lkml.kernel.org/r/1494654390-23861-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-24 09:50:27 +02:00
Baoquan He
d52e7d5a95 x86/KASLR: Parse all 'memmap=' boot option entries
In commit:

  f28442497b ("x86/boot: Fix KASLR and memmap= collision")

... the memmap= option is parsed so that KASLR can avoid those reserved
regions. It uses cmdline_find_option() to get the value if memmap=
is specified, however the problem is that cmdline_find_option() can only
find the last entry if multiple memmap entries are provided. This
is not correct.

Address this by checking each command line token for a "memmap=" match
and parse each instance instead of using cmdline_find_option().

Signed-off-by: Baoquan He <bhe@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dan.j.williams@intel.com
Cc: douly.fnst@cn.fujitsu.com
Cc: dyoung@redhat.com
Cc: m.mizuma@jp.fujitsu.com
Link: http://lkml.kernel.org/r/1494654390-23861-2-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-24 09:50:27 +02:00
Rob Landley
3780578761 x86/boot: Use CROSS_COMPILE prefix for readelf
The boot code Makefile contains a straight 'readelf' invocation. This
causes build warnings in cross compile environments, when there is no
unprefixed readelf accessible via $PATH.

Add the missing $(CROSS_COMPILE) prefix.

[ tglx: Rewrote changelog ]

Fixes: 98f7852537 ("x86/boot: Refuse to build with data relocations")
Signed-off-by: Rob Landley <rob@landley.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: "H.J. Lu" <hjl.tools@gmail.com>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/ced18878-693a-9576-a024-113ef39a22c0@landley.net
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-05-21 13:04:27 +02:00
Xunlei Pang
66aad4fdf2 x86/mm: Add support for gbpages to kernel_ident_mapping_init()
Kernel identity mappings on x86-64 kernels are created in two
ways: by the early x86 boot code, or by kernel_ident_mapping_init().

Native kernels (which is the dominant usecase) use the former,
but the kexec and the hibernation code uses kernel_ident_mapping_init().

There's a subtle difference between these two ways of how identity
mappings are created, the current kernel_ident_mapping_init() code
creates identity mappings always using 2MB page(PMD level) - while
the native kernel boot path also utilizes gbpages where available.

This difference is suboptimal both for performance and for memory
usage: kernel_ident_mapping_init() needs to allocate pages for the
page tables when creating the new identity mappings.

This patch adds 1GB page(PUD level) support to kernel_ident_mapping_init()
to address these concerns.

The primary advantage would be better TLB coverage/performance,
because we'd utilize 1GB TLBs instead of 2MB ones.

It is also useful for machines with large number of memory to
save paging structure allocations(around 4MB/TB using 2MB page)
when setting identity mappings for all the memory, after using
1GB page it will consume only 8KB/TB.

( Note that this change alone does not activate gbpages in kexec,
  we are doing that in a separate patch. )

Signed-off-by: Xunlei Pang <xlpang@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: akpm@linux-foundation.org
Cc: kexec@lists.infradead.org
Link: http://lkml.kernel.org/r/1493862171-8799-1-git-send-email-xlpang@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-08 08:28:40 +02:00
Kees Cook
60854a12d2 x86/boot: Declare error() as noreturn
The compressed boot function error() is used to halt execution, but it
wasn't marked with "noreturn". This fixes that in preparation for
supporting kernel FORTIFY_SOURCE, which uses the noreturn annotation
on panic, and calls error(). GCC would warn about a noreturn function
calling a non-noreturn function:

  arch/x86/boot/compressed/misc.c: In function ‘fortify_panic’:
  arch/x86/boot/compressed/misc.c:416:1: warning: ‘noreturn’ function does return
   }
 ^

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Daniel Micay <danielmicay@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20170506045116.GA2879@beast
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-05-07 10:59:05 +02:00
Linus Torvalds
d3b5d35290 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "The main x86 MM changes in this cycle were:

   - continued native kernel PCID support preparation patches to the TLB
     flushing code (Andy Lutomirski)

   - various fixes related to 32-bit compat syscall returning address
     over 4Gb in applications, launched from 64-bit binaries - motivated
     by C/R frameworks such as Virtuozzo. (Dmitry Safonov)

   - continued Intel 5-level paging enablement: in particular the
     conversion of x86 GUP to the generic GUP code. (Kirill A. Shutemov)

   - x86/mpx ABI corner case fixes/enhancements (Joerg Roedel)

   - ... plus misc updates, fixes and cleanups"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (62 commits)
  mm, zone_device: Replace {get, put}_zone_device_page() with a single reference to fix pmem crash
  x86/mm: Fix flush_tlb_page() on Xen
  x86/mm: Make flush_tlb_mm_range() more predictable
  x86/mm: Remove flush_tlb() and flush_tlb_current_task()
  x86/vm86/32: Switch to flush_tlb_mm_range() in mark_screen_rdonly()
  x86/mm/64: Fix crash in remove_pagetable()
  Revert "x86/mm/gup: Switch GUP to the generic get_user_page_fast() implementation"
  x86/boot/e820: Remove a redundant self assignment
  x86/mm: Fix dump pagetables for 4 levels of page tables
  x86/mpx, selftests: Only check bounds-vs-shadow when we keep shadow
  x86/mpx: Correctly report do_mpx_bt_fault() failures to user-space
  Revert "x86/mm/numa: Remove numa_nodemask_from_meminfo()"
  x86/espfix: Add support for 5-level paging
  x86/kasan: Extend KASAN to support 5-level paging
  x86/mm: Add basic defines/helpers for CONFIG_X86_5LEVEL=y
  x86/paravirt: Add 5-level support to the paravirt code
  x86/mm: Define virtual memory map for 5-level paging
  x86/asm: Remove __VIRTUAL_MASK_SHIFT==47 assert
  x86/boot: Detect 5-level paging support
  x86/mm/numa: Remove numa_nodemask_from_meminfo()
  ...
2017-05-01 23:54:56 -07:00
Baoquan He
da63b6b200 x86/KASLR: Fix kexec kernel boot crash when KASLR randomization fails
Dave found that a kdump kernel with KASLR enabled will reset to the BIOS
immediately if physical randomization failed to find a new position for
the kernel. A kernel with the 'nokaslr' option works in this case.

The reason is that KASLR will install a new page table for the identity
mapping, while it missed building it for the original kernel location
if KASLR physical randomization fails.

This only happens in the kexec/kdump kernel, because the identity mapping
has been built for kexec/kdump in the 1st kernel for the whole memory by
calling init_pgtable(). Here if physical randomizaiton fails, it won't build
the identity mapping for the original area of the kernel but change to a
new page table '_pgtable'. Then the kernel will triple fault immediately
caused by no identity mappings.

The normal kernel won't see this bug, because it comes here via startup_32()
and CR3 will be set to _pgtable already. In startup_32() the identity
mapping is built for the 0~4G area. In KASLR we just append to the existing
area instead of entirely overwriting it for on-demand identity mapping
building. So the identity mapping for the original area of kernel is still
there.

To fix it we just switch to the new identity mapping page table when physical
KASLR succeeds. Otherwise we keep the old page table unchanged just like
"nokaslr" does.

Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1493278940-5885-1-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-28 08:31:15 +02:00
Ashish Kalra
d594aa0277 x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup
The minimum size for a new stack (512 bytes) setup for arch/x86/boot components
when the bootloader does not setup/provide a stack for the early boot components
is not "enough".

The setup code executing as part of early kernel startup code, uses the stack
beyond 512 bytes and accidentally overwrites and corrupts part of the BSS
section. This is exposed mostly in the early video setup code, where
it was corrupting BSS variables like force_x, force_y, which in-turn affected
kernel parameters such as screen_info (screen_info.orig_video_cols) and
later caused an exception/panic in console_init().

Most recent boot loaders setup the stack for early boot components, so this
stack overwriting into BSS section issue has not been exposed.

Signed-off-by: Ashish Kalra <ashish@bluestacks.com>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170419152015.10011-1-ashishkalra@Ashishs-MacBook-Pro.local
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-20 10:05:23 +02:00
Ingo Molnar
e5185a76a2 Merge branch 'x86/boot' into x86/mm, to avoid conflict
There's a conflict between ongoing level-5 paging support and
the E820 rewrite. Since the E820 rewrite is essentially ready,
merge it into x86/mm to reduce tree conflicts.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 08:56:05 +02:00
Ingo Molnar
4729277156 Merge branch 'WIP.x86/boot' into x86/boot, to pick up ready branch
The E820 rework in WIP.x86/boot has gone through a couple of weeks
of exposure in -tip, merge it in a wider fashion.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-11 08:49:31 +02:00
Kirill A. Shutemov
3677d4c6a2 x86/boot: Detect 5-level paging support
In this initial implementation we force-require 5-level paging support
from the hardware, when compiled with CONFIG_X86_5LEVEL=y. (The kernel
will panic during boot on CPUs that don't support 5-level paging.)

We will implement boot-time switch between 4- and 5-level paging later.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170330080731.65421-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-04 08:22:33 +02:00
Zhengyi Shen
6b1cc946dd x86/boot: Include missing header file
Sparse complains about missing forward declarations:

arch/x86/boot/compressed/error.c:8:6:
	warning: symbol 'warn' was not declared. Should it be static?
arch/x86/boot/compressed/error.c:15:6:
	warning: symbol 'error' was not declared. Should it be static?

Include the missing header file.

Signed-off-by: Zhengyi Shen <shenzhengyi@gmail.com>
Acked-by: Kess Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/1490770820-24472-1-git-send-email-shenzhengyi@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-03-31 10:43:42 +02:00
Zhengyi Shen
5af218439f x86/boot: Fix Sparse warning by including required header file
Include declarations for various symbols defined in the error.h header file
to fix the following Sparse warnings:

  arch/x86/boot/compressed/error.c:8:6:
	warning: symbol 'warn' was not declared. Should it be static?
  arch/x86/boot/compressed/error.c:15:6:
	warning: symbol 'error' was not declared. Should it be static?

Signed-off-by: Zhengyi Shen <shenzhengyi@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1490770820-24472-1-git-send-email-shenzhengyi@gmail.com
[ Fixed/enhanced the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-31 08:13:54 +02:00
Ingo Molnar
0871d5a66d Merge branch 'linus' into WIP.x86/boot, to fix up conflicts and to pick up updates
Conflicts:
	arch/x86/xen/setup.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-01 09:02:26 +01:00
Linus Torvalds
292d386743 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Misc updates:

   - fix e820 error handling

   - convert page table setup code from assembly to C

   - fix kexec environment bug

   - ... plus small cleanups"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/kconfig: Remove misleading note regarding hibernation and KASLR
  x86/boot: Fix KASLR and memmap= collision
  x86/e820/32: Fix e820_search_gap() error handling on x86-32
  x86/boot/32: Convert the 32-bit pgtable setup code from assembly to C
  x86/e820: Make e820_search_gap() static and remove unused variables
2017-02-20 14:04:37 -08:00
David Howells
de8cb45862 efi: Get and store the secure boot status
Get the firmware's secure-boot status in the kernel boot wrapper and stash
it somewhere that the main kernel image can find.

The efi_get_secureboot() function is extracted from the ARM stub and (a)
generalised so that it can be called from x86 and (b) made to use
efi_call_runtime() so that it can be run in mixed-mode.

For x86, it is stored in boot_params and can be overridden by the boot
loader or kexec.  This allows secure-boot mode to be passed on to a new
kernel.

Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-5-git-send-email-ard.biesheuvel@linaro.org
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-07 10:42:10 +01:00
David Howells
a2cd2f3f29 x86/efi: Allow invocation of arbitrary runtime services
Provide the ability to perform mixed-mode runtime service calls for x86 in
the same way the following commit provided the ability to invoke for boot
services:

  0a637ee612 ("x86/efi: Allow invocation of arbitrary boot services")

Suggested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1486380166-31868-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-07 10:42:09 +01:00
Lukas Wunner
db4545d9a7 x86/efi: Deduplicate efi_char16_printk()
Eliminate the separate 32-bit and 64x- bit code paths by way of the shiny
new efi_call_proto() macro.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-3-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 08:45:43 +01:00
Lukas Wunner
2bd79f30ee efi: Deduplicate efi_file_size() / _read() / _close()
There's one ARM, one x86_32 and one x86_64 version which can be folded
into a single shared version by masking their differences with the shiny
new efi_call_proto() macro.

No functional change intended.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1485868902-20401-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-01 08:45:42 +01:00
Ingo Molnar
7410aa1ca3 x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures
Linus pointed out that relying on the compiler to pack structures with
enums is fragile not just for the kernel, but for external tooling as
well which might rely on our UAPI headers.

So separate the two from each other: introduce 'struct boot_e820_entry',
which is the boot protocol entry format.

This actually simplifies the code, as e820__update_table() is now never
called directly with boot protocol table entries - we can rely on
append_e820_table() and do a e820__update_table() call afterwards.

( This will allow further simplifications of __e820__update_table(),
  but that will be done in a separate patch. )

This change also has the side effect of not modifying the bootparams structure
anymore - which might be useful for debugging. In theory we could even constify
the boot_params structure - at least from the E820 code's point of view.

Remove the uapi/asm/e820/types.h file, as it's not used anymore - all
kernel side E820 types are defined in asm/e820/types.h.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-29 13:39:32 +01:00
Ingo Molnar
09821ff1d5 x86/boot/e820: Prefix the E820_* type names with "E820_TYPE_"
So there's a number of constants that start with "E820" but which
are not types - these create a confusing mixture when seen together
with 'enum e820_type' values:

	E820MAP
	E820NR
	E820_X_MAX
	E820MAX

To better differentiate the 'enum e820_type' values prefix them
with E820_TYPE_.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 22:55:22 +01:00
Ingo Molnar
61a5010163 x86/boot/e820: Rename everything to e820_table
No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:16 +01:00
Ingo Molnar
acd4c04872 x86/boot/e820: Rename 'e820_map' variables to 'e820_array'
In line with the rename to 'struct e820_array', harmonize the naming of common e820
table variable names as well:

 e820          =>  e820_array
 e820_saved    =>  e820_array_saved
 e820_map      =>  e820_array
 initial_e820  =>  e820_array_init

This makes the variable names more consistent  and easier to grep for.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:15 +01:00
Ingo Molnar
8ec67d97bf x86/boot/e820: Rename the basic e820 data types to 'struct e820_entry' and 'struct e820_array'
The 'e820entry' and 'e820map' names have various annoyances:

 - the missing underscore departs from the usual kernel style
   and makes the code look weird,

 - in the past I kept confusing the 'map' with the 'entry', because
   a 'map' is ambiguous in that regard,

 - it's not really clear from the 'e820map' that this is a regular
   C array.

Rename them to 'struct e820_entry' and 'struct e820_array' accordingly.

( Leave the legacy UAPI header alone but do the rename in the bootparam.h
  and e820/types.h file - outside tools relying on these defines should
  either adjust their code, or should use the legacy header, or should
  create their private copies for the definitions. )

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:33:14 +01:00
Ingo Molnar
b0bd00d6fe x86/boot/e820: Remove assembly guard from asm/e820/types.h
There's an assembly guard in asm/e820/types.h, and only
a single .S file includes this header: arch/x86/boot/header.S,
but it does not actually make use of any of the E820 defines.

Remove the inclusion and remove the assembly guard as well.

No change in functionality.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:31:15 +01:00
Ingo Molnar
5520b7e7d2 x86/boot/e820: Remove spurious asm/e820/api.h inclusions
A commonly used lowlevel x86 header, asm/pgtable.h, includes asm/e820/api.h
spuriously, without making direct use of it.

Removing it is not simple: over the years various .c code learned to rely
on this indirect inclusion.

Remove the unnecessary include - this should speed up the kernel build a bit,
as a large header is not included anymore in totally unrelated code.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:31:14 +01:00
Ingo Molnar
66441bd3cf x86/boot/e820: Move asm/e820.h to asm/e820/api.h
In line with asm/e820/types.h, move the e820 API declarations to
asm/e820/api.h and update all usage sites.

This is just a mechanical, obviously correct move & replace patch,
there will be subsequent changes to clean up the code and to make
better use of the new header organization.

Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:31:13 +01:00
Ingo Molnar
9a1f4150fe Merge branch 'linus' into x86/boot, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-28 09:30:11 +01:00
Dave Jiang
f28442497b x86/boot: Fix KASLR and memmap= collision
CONFIG_RANDOMIZE_BASE=y relocates the kernel to a random base address.

However it does not take into account the memmap= parameter passed in from
the kernel command line. This results in the kernel sometimes being put in
the middle of memmap.

Teach KASLR to not insert the kernel in memmap defined regions. We support
up to 4 memmap regions: any additional regions will cause KASLR to disable.

The mem_avoid set has been augmented to add up to 4 unusable regions of
memmaps provided by the user to exclude those regions from the set of valid
address range to insert the uncompressed kernel image.

The nn@ss ranges will be skipped by the mem_avoid set since it indicates
that memory is useable.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: dan.j.williams@intel.com
Cc: david@fromorbit.com
Cc: linux-nvdimm@lists.01.org
Link: http://lkml.kernel.org/r/148417664156.131935.2248592164852799738.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-01-25 12:35:50 +01:00
Nicholas Mc Guire
fac69d0efa x86/boot: Add missing declaration of string functions
Add the missing declarations of basic string functions to string.h to allow
a clean build.

Fixes: 5be8656615 ("String-handling functions for the new x86 setup code.")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Link: http://lkml.kernel.org/r/1483781911-21399-1-git-send-email-hofrat@osadl.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-01-09 11:53:05 +01:00
Andy Lutomirski
426d1aff31 Revert "x86/boot: Fail the boot if !M486 and CPUID is missing"
This reverts commit ed68d7e9b9.

The patch wasn't quite correct -- there are non-Intel (and hence
non-486) CPUs that we support that don't have CPUID.  Since we no
longer require CPUID for sync_core(), just revert the patch.

I think the relevant CPUs are Geode and Elan, but I'm not sure.

In principle, we should try to do better at identifying CPUID-less
CPUs in early boot, but that's more complicated.

Reported-by: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Matthew Whitehead <tedheadster@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: xen-devel <Xen-devel@lists.xen.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/82acde18a108b8e353180dd6febcc2876df33f24.1481307769.git.luto@kernel.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-19 11:54:20 +01:00
Linus Torvalds
a9042defa2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
Pull trivial updates from Jiri Kosina.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
  NTB: correct ntb_spad_count comment typo
  misc: ibmasm: fix typo in error message
  Remove references to dead make variable LINUX_INCLUDE
  Remove last traces of ikconfig.h
  treewide: Fix printk() message errors
  Documentation/device-mapper: s/getsize/getsz/
2016-12-14 11:12:25 -08:00
Paul Bolle
846221cfb8 Remove references to dead make variable LINUX_INCLUDE
Commit 4fd06960f1 ("Use the new x86 setup code for i386") introduced a
reference to the make variable LINUX_INCLUDE. That reference got moved
around a bit and copied twice and now there are three references to it.

There has never been a definition of that variable. (Presumably that is
because it started out as a mistyped reference to LINUXINCLUDE.) So this
reference has always been an empty string. Let's remove it before it
spreads any further.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2016-12-14 10:54:28 +01:00
Linus Torvalds
06cc6b969c Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "Misc cleanups/simplifications by Borislav Petkov, Paul Bolle and Wei
  Yang"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/64: Optimize fixmap page fixup
  x86/boot: Simplify the GDTR calculation assembly code a bit
  x86/boot/build: Remove always empty $(USERINCLUDE)
2016-12-12 14:13:30 -08:00
Linus Torvalds
3940cf0b3d Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI updates from Ingo Molnar:
 "The main changes in this development cycle were:

   - Implement EFI dev path parser and other changes to fully support
     thunderbolt devices on Apple Macbooks (Lukas Wunner)

   - Add RNG seeding via the EFI stub, on ARM/arm64 (Ard Biesheuvel)

   - Expose EFI framebuffer configuration to user-space, to improve
     tooling (Peter Jones)

   - Misc fixes and cleanups (Ivan Hu, Wei Yongjun, Yisheng Xie, Dan
     Carpenter, Roy Franz)"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  efi/libstub: Make efi_random_alloc() allocate below 4 GB on 32-bit
  thunderbolt: Compile on x86 only
  thunderbolt, efi: Fix Kconfig dependencies harder
  thunderbolt, efi: Fix Kconfig dependencies
  thunderbolt: Use Device ROM retrieved from EFI
  x86/efi: Retrieve and assign Apple device properties
  efi: Allow bitness-agnostic protocol calls
  efi: Add device path parser
  efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table
  efi/libstub: Add random.c to ARM build
  efi: Add support for seeding the RNG from a UEFI config table
  MAINTAINERS: Add ARM and arm64 EFI specific files to EFI subsystem
  efi/libstub: Fix allocation size calculations
  efi/efivar_ssdt_load: Don't return success on allocation failure
  efifb: Show framebuffer layout as device attributes
  efi/efi_test: Use memdup_user() as a cleanup
  efi/efi_test: Fix uninitialized variable 'rv'
  efi/efi_test: Fix uninitialized variable 'datasize'
  efi/arm*: Fix efi_init() error handling
  efi: Remove unused include of <linux/version.h>
2016-12-12 10:03:44 -08:00
H.J. Lu
a980ce352f x86/build: Build compressed x86 kernels as PIE when !CONFIG_RELOCATABLE as well
Since the bootloader may load the compressed x86 kernel at any address,
it should always be built as PIE, not just when CONFIG_RELOCATABLE=y.

Otherwise, linker in binutils 2.27 will optimize GOT load into the
absolute address when building the compressed x86 kernel as a non-PIE
executable.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
[ Small wording changes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-21 11:05:28 +01:00
Andy Lutomirski
ed68d7e9b9 x86/boot: Fail the boot if !M486 and CPUID is missing
Linux will have all kinds of sporadic problems on systems that don't
have the CPUID instruction unless CONFIG_M486=y.  In particular,
sync_core() will explode.

I believe that these kernels had a better chance of working before
commit 05fb3c199b ("x86/boot: Initialize FPU and X86_FEATURE_ALWAYS
even if we don't have CPUID").  That commit inadvertently fixed a
serious bug: we used to fail to detect the FPU if CPUID wasn't
present.  Because we also used to forget to set X86_FEATURE_ALWAYS, we
end up with no cpu feature bits set at all.  This meant that
alternative patching didn't do anything and, if paravirt was disabled,
we could plausibly finish the entire boot process without calling
sync_core().

Rather than trying to work around these issues, just have the kernel
fail loudly if it's running on a CPUID-less 486, doesn't have CPUID,
and doesn't have CONFIG_M486 set.

Reported-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/70eac6639f23df8be5fe03fa1984aedd5d40077a.1479598603.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-21 09:04:32 +01:00
Lukas Wunner
58c5475aba x86/efi: Retrieve and assign Apple device properties
Apple's EFI drivers supply device properties which are needed to support
Macs optimally. They contain vital information which cannot be obtained
any other way (e.g. Thunderbolt Device ROM). They're also used to convey
the current device state so that OS drivers can pick up where EFI
drivers left (e.g. GPU mode setting).

There's an EFI driver dubbed "AAPL,PathProperties" which implements a
per-device key/value store. Other EFI drivers populate it using a custom
protocol. The macOS bootloader /System/Library/CoreServices/boot.efi
retrieves the properties with the same protocol. The kernel extension
AppleACPIPlatform.kext subsequently merges them into the I/O Kit
registry (see ioreg(8)) where they can be queried by other kernel
extensions and user space.

This commit extends the efistub to retrieve the device properties before
ExitBootServices is called. It assigns them to devices in an fs_initcall
so that they can be queried with the API in <linux/property.h>.

Note that the device properties will only be available if the kernel is
booted with the efistub. Distros should adjust their installers to
always use the efistub on Macs. grub with the "linux" directive will not
work unless the functionality of this commit is duplicated in grub.
(The "linuxefi" directive should work but is not included upstream as of
this writing.)

The custom protocol has GUID 91BD12FE-F6C3-44FB-A5B7-5122AB303AE0 and
looks like this:

typedef struct {
	unsigned long version; /* 0x10000 */
	efi_status_t (*get) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_NOT_FOUND, EFI_BUFFER_TOO_SMALL */
	efi_status_t (*set) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name,
		IN	void *property_value,
		IN	u32 property_value_len);
		/* allocates copies of property name and value */
		/* EFI_SUCCESS, EFI_OUT_OF_RESOURCES */
	efi_status_t (*del) (
		IN	struct apple_properties_protocol *this,
		IN	struct efi_dev_path *device,
		IN	efi_char16_t *property_name);
		/* EFI_SUCCESS, EFI_NOT_FOUND */
	efi_status_t (*get_all) (
		IN	struct apple_properties_protocol *this,
		OUT	void *buffer,
		IN OUT	u32 *buffer_len);
		/* EFI_SUCCESS, EFI_BUFFER_TOO_SMALL */
} apple_properties_protocol;

Thanks to Pedro Vilaça for this blog post which was helpful in reverse
engineering Apple's EFI drivers and bootloader:
https://reverse.put.as/2016/06/25/apple-efi-firmware-passwords-and-the-scbo-myth/

If someone at Apple is reading this, please note there's a memory leak
in your implementation of the del() function as the property struct is
freed but the name and value allocations are not.

Neither the macOS bootloader nor Apple's EFI drivers check the protocol
version, but we do to avoid breakage if it's ever changed. It's been the
same since at least OS X 10.6 (2009).

The get_all() function conveniently fills a buffer with all properties
in marshalled form which can be passed to the kernel as a setup_data
payload. The number of device properties is dynamic and can change
between a first invocation of get_all() (to determine the buffer size)
and a second invocation (to retrieve the actual buffer), hence the
peculiar loop which does not finish until the buffer size settles.
The macOS bootloader does the same.

The setup_data payload is later on unmarshalled in an fs_initcall. The
idea is that most buses instantiate devices in "subsys" initcall level
and drivers are usually bound to these devices in "device" initcall
level, so we assign the properties in-between, i.e. in "fs" initcall
level.

This assumes that devices to which properties pertain are instantiated
from a "subsys" initcall or earlier. That should always be the case
since on macOS, AppleACPIPlatformExpert::matchEFIDevicePath() only
supports ACPI and PCI nodes and we've fully scanned those buses during
"subsys" initcall level.

The second assumption is that properties are only needed from a "device"
initcall or later. Seems reasonable to me, but should this ever not work
out, an alternative approach would be to store the property sets e.g. in
a btree early during boot. Then whenever device_add() is called, an EFI
Device Path would have to be constructed for the newly added device,
and looked up in the btree. That way, the property set could be assigned
to the device immediately on instantiation. And this would also work for
devices instantiated in a deferred fashion. It seems like this approach
would be more complicated and require more code. That doesn't seem
justified without a specific use case.

For comparison, the strategy on macOS is to assign properties to objects
in the ACPI namespace (AppleACPIPlatformExpert::mergeEFIProperties()).
That approach is definitely wrong as it fails for devices not present in
the namespace: The NHI EFI driver supplies properties for attached
Thunderbolt devices, yet on Macs with Thunderbolt 1 only one device
level behind the host controller is described in the namespace.
Consequently macOS cannot assign properties for chained devices. With
Thunderbolt 2 they started to describe three device levels behind host
controllers in the namespace but this grossly inflates the SSDT and
still fails if the user daisy-chained more than three devices.

We copy the property names and values from the setup_data payload to
swappable virtual memory and afterwards make the payload available to
the page allocator. This is just for the sake of good housekeeping, it
wouldn't occupy a meaningful amount of physical memory (4444 bytes on my
machine). Only the payload is freed, not the setup_data header since
otherwise we'd break the list linkage and we cannot safely update the
predecessor's ->next link because there's no locking for the list.

The payload is currently not passed on to kexec'ed kernels, same for PCI
ROMs retrieved by setup_efi_pci(). This can be added later if there is
demand by amending setup_efi_state(). The payload can then no longer be
made available to the page allocator of course.

Tested-by: Lukas Wunner <lukas@wunner.de> [MacBookPro9,1]
Tested-by: Pierre Moreau <pierre.morrow@free.fr> [MacBookPro11,3]
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andreas Noever <andreas.noever@gmail.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pedro Vilaça <reverser@put.as>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: grub-devel@gnu.org
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-9-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-13 08:23:16 +01:00
Wei Yang
064025f7ea x86/boot: Simplify the GDTR calculation assembly code a bit
This patch calculates the GDTR's base address via a single instruction.

( EBP contains the address where it is loaded and GDTR's base address is
  already set to "gdt" in compilation. It is fine to get the correct base
  address by adding the delta to GDTR's base address. )

Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1478015364-5547-1-git-send-email-richard.weiyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-07 08:33:59 +01:00
Paul Bolle
0acba3f918 x86/boot/build: Remove always empty $(USERINCLUDE)
Commmit b6eea87fc6:

  ("x86, boot: Explicitly include autoconf.h for hostprogs")

correctly noted:

    [...] that because $(USERINCLUDE) isn't exported by
    the top-level Makefile it's actually empty in arch/x86/boot/Makefile.

So let's do the sane thing and remove the reference to that make variable.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: David Howells <dhowells@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1478166468-9760-1-git-send-email-pebolle@tiscali.nl
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-07 07:30:01 +01:00
Ingo Molnar
5465fe0fc3 * Refactor the EFI memory map code into architecture neutral files
and allow drivers to permanently reserve EFI boot services regions
    on x86, as well as ARM/arm64 - Matt Fleming
 
  * Add ARM support for the EFI esrt driver - Ard Biesheuvel
 
  * Make the EFI runtime services and efivar API interruptible by
    swapping spinlocks for semaphores - Sylvain Chouleur
 
  * Provide the EFI identity mapping for kexec which allows kexec to
    work on SGI/UV platforms with requiring the "noefi" kernel command
    line parameter - Alex Thorlton
 
  * Add debugfs node to dump EFI page tables on arm64 - Ard Biesheuvel
 
  * Merge the EFI test driver being carried out of tree until now in
    the FWTS project - Ivan Hu
 
  * Expand the list of flags for classifying EFI regions as "RAM" on
    arm64 so we align with the UEFI spec - Ard Biesheuvel
 
  * Optimise out the EFI mixed mode if it's unsupported (CONFIG_X86_32)
    or disabled (CONFIG_EFI_MIXED=n) and switch the early EFI boot
    services function table for direct calls, alleviating us from
    having to maintain the custom function table - Lukas Wunner
 
  * Miscellaneous cleanups and fixes
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into efi/core

Pull EFI updates from Matt Fleming:

"* Refactor the EFI memory map code into architecture neutral files
   and allow drivers to permanently reserve EFI boot services regions
   on x86, as well as ARM/arm64 - Matt Fleming

 * Add ARM support for the EFI esrt driver - Ard Biesheuvel

 * Make the EFI runtime services and efivar API interruptible by
   swapping spinlocks for semaphores - Sylvain Chouleur

 * Provide the EFI identity mapping for kexec which allows kexec to
   work on SGI/UV platforms with requiring the "noefi" kernel command
   line parameter - Alex Thorlton

 * Add debugfs node to dump EFI page tables on arm64 - Ard Biesheuvel

 * Merge the EFI test driver being carried out of tree until now in
   the FWTS project - Ivan Hu

 * Expand the list of flags for classifying EFI regions as "RAM" on
   arm64 so we align with the UEFI spec - Ard Biesheuvel

 * Optimise out the EFI mixed mode if it's unsupported (CONFIG_X86_32)
   or disabled (CONFIG_EFI_MIXED=n) and switch the early EFI boot
   services function table for direct calls, alleviating us from
   having to maintain the custom function table - Lukas Wunner

 * Miscellaneous cleanups and fixes"

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-13 20:21:55 +02:00
Lukas Wunner
0a637ee612 x86/efi: Allow invocation of arbitrary boot services
We currently allow invocation of 8 boot services with efi_call_early().
Not included are LocateHandleBuffer and LocateProtocol in particular.
For graphics output or to retrieve PCI ROMs and Apple device properties,
we're thus forced to use the LocateHandle + AllocatePool + LocateHandle
combo, which is cumbersome and needs more code.

The ARM folks allow invocation of the full set of boot services but are
restricted to our 8 boot services in functions shared across arches.

Thus, rather than adding just LocateHandleBuffer and LocateProtocol to
struct efi_config, let's rework efi_call_early() to allow invocation of
arbitrary boot services by selecting the 64 bit vs 32 bit code path in
the macro itself.

When compiling for 32 bit or for 64 bit without mixed mode, the unused
code path is optimized away and the binary code is the same as before.
But on 64 bit with mixed mode enabled, this commit adds one compare
instruction to each invocation of a boot service and, depending on the
code path selected, two jump instructions. (Most of the time gcc
arranges the jumps in the 32 bit code path.) The result is a minuscule
performance penalty and the binary code becomes slightly larger and more
difficult to read when disassembled. This isn't a hot path, so these
drawbacks are arguably outweighed by the attainable simplification of
the C code. We have some overhead anyway for thunking or conversion
between calling conventions.

The 8 boot services can consequently be removed from struct efi_config.

No functional change intended (for now).

Example -- invocation of free_pool before (64 bit code path):
0x2d4      movq  %ds:efi_early, %rdx          ; efi_early
0x2db      movq  %ss:arg_0-0x20(%rsp), %rsi
0x2e0      xorl  %eax, %eax
0x2e2      movq  %ds:0x28(%rdx), %rdi         ; efi_early->free_pool
0x2e6      callq *%ds:0x58(%rdx)              ; efi_early->call()

Example -- invocation of free_pool after (64 / 32 bit mixed code path):
0x0dc      movq  %ds:efi_early, %rax          ; efi_early
0x0e3      cmpb  $0, %ds:0x28(%rax)           ; !efi_early->is64 ?
0x0e7      movq  %ds:0x20(%rax), %rdx         ; efi_early->call()
0x0eb      movq  %ds:0x10(%rax), %rax         ; efi_early->boot_services
0x0ef      je    $0x150
0x0f1      movq  %ds:0x48(%rax), %rdi         ; free_pool (64 bit)
0x0f5      xorl  %eax, %eax
0x0f7      callq *%rdx
...
0x150      movl  %ds:0x30(%rax), %edi         ; free_pool (32 bit)
0x153      jmp   $0x0f5

Size of eboot.o text section:
CONFIG_X86_32:                         6464 before, 6318 after
CONFIG_X86_64 && !CONFIG_EFI_MIXED:    7670 before, 7573 after
CONFIG_X86_64 &&  CONFIG_EFI_MIXED:    7670 before, 8319 after

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:57 +01:00
Lukas Wunner
15cf7cae08 x86/efi: Remove unused find_bits() function
Left behind by commit fc37206427 ("efi/libstub: Move Graphics Output
Protocol handling to generic code").

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:50 +01:00
Colin Ian King
ac0e94b63e x86/efi: Initialize status to ensure garbage is not returned on small size
Although very unlikey, if size is too small or zero, then we end up with
status not being set and returning garbage. Instead, initializing status to
EFI_INVALID_PARAMETER to indicate that size is invalid in the calls to
setup_uga32 and setup_uga64.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:08:44 +01:00
Jeffrey Hugo
d64934019f x86/efi: Use efi_exit_boot_services()
The eboot code directly calls ExitBootServices.  This is inadvisable as the
UEFI spec details a complex set of errors, race conditions, and API
interactions that the caller of ExitBootServices must get correct.  The
eboot code attempts allocations after calling ExitBootSerives which is
not permitted per the spec.  Call the efi_exit_boot_services() helper
intead, which handles the allocation scenario properly.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-05 12:40:16 +01:00
Jeffrey Hugo
dadb57abc3 efi/libstub: Allocate headspace in efi_get_memory_map()
efi_get_memory_map() allocates a buffer to store the memory map that it
retrieves.  This buffer may need to be reused by the client after
ExitBootServices() is called, at which point allocations are not longer
permitted.  To support this usecase, provide the allocated buffer size back
to the client, and allocate some additional headroom to account for any
reasonable growth in the map that is likely to happen between the call to
efi_get_memory_map() and the client reusing the buffer.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-05 12:18:17 +01:00
Linus Torvalds
f716a85cd6 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - GCC plugin support by Emese Revfy from grsecurity, with a fixup from
   Kees Cook.  The plugins are meant to be used for static analysis of
   the kernel code.  Two plugins are provided already.

 - reduction of the gcc commandline by Arnd Bergmann.

 - IS_ENABLED / IS_REACHABLE macro enhancements by Masahiro Yamada

 - bin2c fix by Michael Tautschnig

 - setlocalversion fix by Wolfram Sang

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
  gcc-plugins: disable under COMPILE_TEST
  kbuild: Abort build on bad stack protector flag
  scripts: Fix size mismatch of kexec_purgatory_size
  kbuild: make samples depend on headers_install
  Kbuild: don't add obj tree in additional includes
  Kbuild: arch: look for generated headers in obtree
  Kbuild: always prefix objtree in LINUXINCLUDE
  Kbuild: avoid duplicate include path
  Kbuild: don't add ../../ to include path
  vmlinux.lds.h: replace config_enabled() with IS_ENABLED()
  kconfig.h: allow to use IS_{ENABLE,REACHABLE} in macro expansion
  kconfig.h: use already defined macros for IS_REACHABLE() define
  export.h: use __is_defined() to check if __KSYM_* is defined
  kconfig.h: use __is_defined() to check if MODULE is defined
  kbuild: setlocalversion: print error to STDERR
  Add sancov plugin
  Add Cyclomatic complexity GCC plugin
  GCC plugin infrastructure
  Shared library support
2016-08-02 16:37:12 -04:00
Linus Torvalds
77cd3d0c43 Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The main changes:

   - add initial commits to randomize kernel memory section virtual
     addresses, enabled via a new kernel option: RANDOMIZE_MEMORY
     (Thomas Garnier, Kees Cook, Baoquan He, Yinghai Lu)

   - enhance KASLR (RANDOMIZE_BASE) physical memory randomization (Kees
     Cook)

   - EBDA/BIOS region boot quirk cleanups (Andy Lutomirski, Ingo Molnar)

   - misc cleanups/fixes"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot: Simplify EBDA-vs-BIOS reservation logic
  x86/boot: Clarify what x86_legacy_features.reserve_bios_regions does
  x86/boot: Reorganize and clean up the BIOS area reservation code
  x86/mm: Do not reference phys addr beyond kernel
  x86/mm: Add memory hotplug support for KASLR memory randomization
  x86/mm: Enable KASLR for vmalloc memory regions
  x86/mm: Enable KASLR for physical mapping memory regions
  x86/mm: Implement ASLR for kernel memory regions
  x86/mm: Separate variable for trampoline PGD
  x86/mm: Add PUD VA support for physical mapping
  x86/mm: Update physical mapping variable names
  x86/mm: Refactor KASLR entropy functions
  x86/KASLR: Fix boot crash with certain memory configurations
  x86/boot/64: Add forgotten end of function marker
  x86/KASLR: Allow randomization below the load address
  x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
  x86/KASLR: Randomize virtual address separately
  x86/KASLR: Clarify identity map interface
  x86/boot: Refuse to build with data relocations
  x86/KASLR, x86/power: Remove x86 hibernation restrictions
2016-07-25 17:32:28 -07:00
Linus Torvalds
0f657262d5 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm updates from Ingo Molnar:
 "Various x86 low level modifications:

   - preparatory work to support virtually mapped kernel stacks (Andy
     Lutomirski)

   - support for 64-bit __get_user() on 32-bit kernels (Benjamin
     LaHaise)

   - (involved) workaround for Knights Landing CPU erratum (Dave Hansen)

   - MPX enhancements (Dave Hansen)

   - mremap() extension to allow remapping of the special VDSO vma, for
     purposes of user level context save/restore (Dmitry Safonov)

   - hweight and entry code cleanups (Borislav Petkov)

   - bitops code generation optimizations and cleanups with modern GCC
     (H. Peter Anvin)

   - syscall entry code optimizations (Paolo Bonzini)"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (43 commits)
  x86/mm/cpa: Add missing comment in populate_pdg()
  x86/mm/cpa: Fix populate_pgd(): Stop trying to deallocate failed PUDs
  x86/syscalls: Add compat_sys_preadv64v2/compat_sys_pwritev64v2
  x86/smp: Remove unnecessary initialization of thread_info::cpu
  x86/smp: Remove stack_smp_processor_id()
  x86/uaccess: Move thread_info::addr_limit to thread_struct
  x86/dumpstack: Rename thread_struct::sig_on_uaccess_error to sig_on_uaccess_err
  x86/uaccess: Move thread_info::uaccess_err and thread_info::sig_on_uaccess_err to thread_struct
  x86/dumpstack: When OOPSing, rewind the stack before do_exit()
  x86/mm/64: In vmalloc_fault(), use CR3 instead of current->active_mm
  x86/dumpstack/64: Handle faults when printing the "Stack: " part of an OOPS
  x86/dumpstack: Try harder to get a call trace on stack overflow
  x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables()
  x86/mm/cpa: In populate_pgd(), don't set the PGD entry until it's populated
  x86/mm/hotplug: Don't remove PGD entries in remove_pagetable()
  x86/mm: Use pte_none() to test for empty PTE
  x86/mm: Disallow running with 32-bit PTEs to work around erratum
  x86/mm: Ignore A/D bits in pte/pmd/pud_none()
  x86/mm: Move swap offset/type up in PTE to work around erratum
  x86/entry: Inline enter_from_user_mode()
  ...
2016-07-25 15:34:18 -07:00
Arnd Bergmann
58ab5e0c2c Kbuild: arch: look for generated headers in obtree
There are very few files that need add an -I$(obj) gcc for the preprocessor
or the assembler. For C files, we add always these for both the objtree and
srctree, but for the other ones we require the Makefile to add them, and
Kbuild then adds it for both trees.

As a preparation for changing the meaning of the -I$(obj) directive to
only refer to the srctree, this changes the two instances in arch/x86 to use
an explictit $(objtree) prefix where needed, otherwise we won't find the
headers any more, as reported by the kbuild 0day builder.

arch/x86/realmode/rm/realmode.lds.S:75:20: fatal error: pasyms.h: No such file or directory

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Michal Marek <mmarek@suse.com>
2016-07-18 21:31:35 +02:00
Ingo Molnar
38452af242 Merge branch 'x86/asm' into x86/mm, to resolve conflicts
Conflicts:
	tools/testing/selftests/x86/Makefile

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-15 10:26:04 +02:00
Dave Hansen
e4a84be6f0 x86/mm: Disallow running with 32-bit PTEs to work around erratum
The Intel(R) Xeon Phi(TM) Processor x200 Family (codename: Knights
Landing) has an erratum where a processor thread setting the Accessed
or Dirty bits may not do so atomically against its checks for the
Present bit.  This may cause a thread (which is about to page fault)
to set A and/or D, even though the Present bit had already been
atomically cleared.

These bits are truly "stray".  In the case of the Dirty bit, the
thread associated with the stray set was *not* allowed to write to
the page.  This means that we do not have to launder the bit(s); we
can simply ignore them.

If the PTE is used for storing a swap index or a NUMA migration index,
the A bit could be misinterpreted as part of the swap type.  The stray
bits being set cause a software-cleared PTE to be interpreted as a
swap entry.  In some cases (like when the swap index ends up being
for a non-existent swapfile), the kernel detects the stray value
and WARN()s about it, but there is no guarantee that the kernel can
always detect it.

When we have 64-bit PTEs (64-bit mode or 32-bit PAE), we were able
to move the swap PTE format around to avoid these troublesome bits.
But, 32-bit non-PAE is tight on bits.  So, disallow it from running
on this hardware.  I can't imagine anyone wanting to run 32-bit
non-highmem kernels on this hardware, but disallowing them from
running entirely is surely the safe thing to do.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dave.hansen@intel.com
Cc: linux-mm@kvack.org
Cc: mhocko@suse.com
Link: http://lkml.kernel.org/r/20160708001914.D0B50110@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-13 09:43:25 +02:00
Thomas Garnier
021182e52f x86/mm: Enable KASLR for physical mapping memory regions
Add the physical mapping in the list of randomized memory regions.

The physical memory mapping holds most allocations from boot and heap
allocators. Knowing the base address and physical memory size, an attacker
can deduce the PDE virtual address for the vDSO memory page. This attack
was demonstrated at CanSecWest 2016, in the following presentation:

  "Getting Physical: Extreme Abuse of Intel Based Paged Systems":
  https://github.com/n3k/CansecWest2016_Getting_Physical_Extreme_Abuse_of_Intel_Based_Paging_Systems/blob/master/Presentation/CanSec2016_Presentation.pdf

(See second part of the presentation).

The exploits used against Linux worked successfully against 4.6+ but
fail with KASLR memory enabled:

  https://github.com/n3k/CansecWest2016_Getting_Physical_Extreme_Abuse_of_Intel_Based_Paging_Systems/tree/master/Demos/Linux/exploits

Similar research was done at Google leading to this patch proposal.

Variants exists to overwrite /proc or /sys objects ACLs leading to
elevation of privileges. These variants were tested against 4.6+.

The page offset used by the compressed kernel retains the static value
since it is not yet randomized during this boot stage.

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-7-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 17:35:15 +02:00
Thomas Garnier
d899a7d146 x86/mm: Refactor KASLR entropy functions
Move the KASLR entropy functions into arch/x86/lib to be used in early
kernel boot for KASLR memory randomization.

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
Cc: Alexander Popov <alpopov@ptsecurity.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lv Zheng <lv.zheng@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/1466556426-32664-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 17:33:45 +02:00
Baoquan He
6daa2ec0b3 x86/KASLR: Fix boot crash with certain memory configurations
Ye Xiaolong reported this boot crash:

|
|  XZ-compressed data is corrupt
|
|   -- System halted
|

Fix the bug in mem_avoid_overlap() of finding the earliest overlap.

Reported-and-tested-by: Ye Xiaolong <xiaolong.ye@intel.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-07-08 14:36:19 +02:00
Colin Ian King
f6d1747f89 x86/efi: Remove unused variable 'efi'
Remove unused variable 'efi', it is never used. This fixes the following
clang build warning:

  arch/x86/boot/compressed/eboot.c:803:2: warning: Value stored to 'efi' is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1466839230-12781-4-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-27 13:06:55 +02:00
Yinghai Lu
e066cc4777 x86/KASLR: Allow randomization below the load address
Currently the kernel image physical address randomization's lower
boundary is the original kernel load address.

For bootloaders that load kernels into very high memory (e.g. kexec),
this means randomization takes place in a very small window at the
top of memory, ignoring the large region of physical memory below
the load address.

Since mem_avoid[] is already correctly tracking the regions that must be
avoided, this patch changes the minimum address to whatever is less:
512M (to conservatively avoid unknown things in lower memory) or the
load address. Now, for example, if the kernel is loaded at 8G, [512M,
8G) will be added to the list of possible physical memory positions.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Rewrote the changelog, refactored the code to use min(). ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1464216334-17200-6-git-send-email-keescook@chromium.org
[ Edited the changelog some more, plus the code comment as well. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:05 +02:00
Kees Cook
ed9f007ee6 x86/KASLR: Extend kernel image physical address randomization to addresses larger than 4G
We want the physical address to be randomized anywhere between
16MB and the top of physical memory (up to 64TB).

This patch exchanges the prior slots[] array for the new slot_areas[]
array, and lifts the limitation of KERNEL_IMAGE_SIZE on the physical
address offset for 64-bit. As before, process_e820_entry() walks
memory and populates slot_areas[], splitting on any detected mem_avoid
collisions.

Finally, since the slots[] array and its associated functions are not
needed any more, so they are removed.

Based on earlier patches by Baoquan He.

Originally-from: Baoquan He <bhe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1464216334-17200-5-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:05 +02:00
Baoquan He
8391c73c96 x86/KASLR: Randomize virtual address separately
The current KASLR implementation randomizes the physical and virtual
addresses of the kernel together (both are offset by the same amount). It
calculates the delta of the physical address where vmlinux was linked
to load and where it is finally loaded. If the delta is not equal to 0
(i.e. the kernel was relocated), relocation handling needs be done.

On 64-bit, this patch randomizes both the physical address where kernel
is decompressed and the virtual address where kernel text is mapped and
will execute from. We now have two values being chosen, so the function
arguments are reorganized to pass by pointer so they can be directly
updated. Since relocation handling only depends on the virtual address,
we must check the virtual delta, not the physical delta for processing
kernel relocations. This also populates the page table for the new
virtual address range. 32-bit does not support a separate virtual address,
so it continues to use the physical offset for its virtual offset.

Additionally updates the sanity checks done on the resulting kernel
addresses since they are potentially separate now.

[kees: rewrote changelog, limited virtual split to 64-bit only, update checks]
[kees: fix CONFIG_RANDOMIZE_BASE=n boot failure]
Signed-off-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1464216334-17200-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:04 +02:00
Kees Cook
11fdf97a3c x86/KASLR: Clarify identity map interface
This extracts the call to prepare_level4() into a top-level function
that the user of the pagetable.c interface must call to initialize
the new page tables. For clarity and to match the "finalize" function,
it has been renamed to initialize_identity_maps(). This function also
gains the initialization of mapping_info so we don't have to do it each
time in add_identity_map().

Additionally add copyright notice to the top, to make it clear that the
bulk of the pagetable.c code was written by Yinghai, and that I just
added bugs later. :)

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1464216334-17200-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:04 +02:00
Kees Cook
98f7852537 x86/boot: Refuse to build with data relocations
The compressed kernel is built with -fPIC/-fPIE so that it can run in any
location a bootloader happens to put it. However, since ELF relocation
processing is not happening (and all the relocation information has
already been stripped at link time), none of the code can use data
relocations (e.g. static assignments of pointers). This is already noted
in a warning comment at the top of misc.c, but this adds an explicit
check for the condition during the linking stage to block any such bugs
from appearing.

If this was in place with the earlier bug in pagetable.c, the build
would fail like this:

  ...
    CC      arch/x86/boot/compressed/pagetable.o
    DATAREL arch/x86/boot/compressed/vmlinux
  error: arch/x86/boot/compressed/pagetable.o has data relocations!
  make[2]: *** [arch/x86/boot/compressed/vmlinux] Error 1
  ...

A clean build shows:

  ...
    CC      arch/x86/boot/compressed/pagetable.o
    DATAREL arch/x86/boot/compressed/vmlinux
    LD      arch/x86/boot/compressed/vmlinux
  ...

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: H.J. Lu <hjl.tools@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1464216334-17200-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:03 +02:00
Kees Cook
65fe935dd2 x86/KASLR, x86/power: Remove x86 hibernation restrictions
With the following fix:

  70595b479ce1 ("x86/power/64: Fix crash whan the hibernation code passes control to the image kernel")

... there is no longer a problem with hibernation resuming a
KASLR-booted kernel image, so remove the restriction.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linux PM list <linux-pm@vger.kernel.org>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-doc@vger.kernel.org
Link: http://lkml.kernel.org/r/20160613221002.GA29719@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-26 12:32:03 +02:00
Ingo Molnar
50c0587eed Merge branch 'linus' into x86/asm, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-06-11 11:25:50 +02:00
H. Peter Anvin
66928b4eb9 x86, asm, boot: Use CC_SET()/CC_OUT() in arch/x86/boot/boot.h
Remove open-coded uses of set instructions to use CC_SET()/CC_OUT() in
arch/x86/boot/boot.h.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Link: http://lkml.kernel.org/r/1465414726-197858-10-git-send-email-hpa@linux.intel.com
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-06-08 12:41:20 -07:00
H. Peter Anvin
117780eef7 x86, asm: use bool for bitops and other assembly outputs
The gcc people have confirmed that using "bool" when combined with
inline assembly always is treated as a byte-sized operand that can be
assumed to be 0 or 1, which is exactly what the SET instruction
emits.  Change the output types and intermediate variables of as many
operations as practical to "bool".

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/1465414726-197858-3-git-send-email-hpa@linux.intel.com
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-06-08 12:41:20 -07:00
H. Peter Anvin
9c77679cad x86, build: copy ldlinux.c32 to image.iso
For newer versions of Syslinux, we need ldlinux.c32 in addition to
isolinux.bin to reside on the boot disk, so if the latter is found,
copy it, too, to the isoimage tree.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Cc: Linux Stable Tree <stable@vger.kernel.org>
2016-06-07 15:54:18 -07:00
Linus Torvalds
5b26fc8824 Merge branch 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild
Pull kbuild updates from Michal Marek:

 - new option CONFIG_TRIM_UNUSED_KSYMS which does a two-pass build and
   unexports symbols which are not used in the current config [Nicolas
   Pitre]

 - several kbuild rule cleanups [Masahiro Yamada]

 - warning option adjustments for gcov etc [Arnd Bergmann]

 - a few more small fixes

* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild: (31 commits)
  kbuild: move -Wunused-const-variable to W=1 warning level
  kbuild: fix if_change and friends to consider argument order
  kbuild: fix adjust_autoksyms.sh for modules that need only one symbol
  kbuild: fix ksym_dep_filter when multiple EXPORT_SYMBOL() on the same line
  gcov: disable -Wmaybe-uninitialized warning
  gcov: disable tree-loop-im to reduce stack usage
  gcov: disable for COMPILE_TEST
  Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES
  Kbuild: change CC_OPTIMIZE_FOR_SIZE definition
  kbuild: forbid kernel directory to contain spaces and colons
  kbuild: adjust ksym_dep_filter for some cmd_* renames
  kbuild: Fix dependencies for final vmlinux link
  kbuild: better abstract vmlinux sequential prerequisites
  kbuild: fix call to adjust_autoksyms.sh when output directory specified
  kbuild: Get rid of KBUILD_STR
  kbuild: rename cmd_as_s_S to cmd_cpp_s_S
  kbuild: rename cmd_cc_i_c to cmd_cpp_i_c
  kbuild: drop redundant "PHONY += FORCE"
  kbuild: delete unnecessary "@:"
  kbuild: mark help target as PHONY
  ...
2016-05-26 22:01:22 -07:00
Linus Torvalds
9a45f036af Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 boot updates from Ingo Molnar:
 "The biggest changes in this cycle were:

   - prepare for more KASLR related changes, by restructuring, cleaning
     up and fixing the existing boot code.  (Kees Cook, Baoquan He,
     Yinghai Lu)

   - simplifly/concentrate subarch handling code, eliminate
     paravirt_enabled() usage.  (Luis R Rodriguez)"

* 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
  x86/KASLR: Clarify purpose of each get_random_long()
  x86/KASLR: Add virtual address choosing function
  x86/KASLR: Return earliest overlap when avoiding regions
  x86/KASLR: Add 'struct slot_area' to manage random_addr slots
  x86/boot: Add missing file header comments
  x86/KASLR: Initialize mapping_info every time
  x86/boot: Comment what finalize_identity_maps() does
  x86/KASLR: Build identity mappings on demand
  x86/boot: Split out kernel_ident_mapping_init()
  x86/boot: Clean up indenting for asm/boot.h
  x86/KASLR: Improve comments around the mem_avoid[] logic
  x86/boot: Simplify pointer casting in choose_random_location()
  x86/KASLR: Consolidate mem_avoid[] entries
  x86/boot: Clean up pointer casting
  x86/boot: Warn on future overlapping memcpy() use
  x86/boot: Extract error reporting functions
  x86/boot: Correctly bounds-check relocations
  x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'
  x86/boot: Fix "run_size" calculation
  x86/boot: Calculate decompression size during boot not build
  ...
2016-05-16 15:54:01 -07:00
Kees Cook
d2d3462f9f x86/KASLR: Clarify purpose of each get_random_long()
KASLR will be calling get_random_long() twice, but the debug output
won't distinguishing between them. This patch adds a report on when it
is fetching the physical vs virtual address. With this, once the virtual
offset is separate, the report changes from:

 KASLR using RDTSC...
 KASLR using RDTSC...

into:

 Physical KASLR using RDTSC...
 Virtual KASLR using RDTSC...

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-7-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:08 +02:00
Baoquan He
071a74930e x86/KASLR: Add virtual address choosing function
To support randomizing the kernel virtual address separately from the
physical address, this patch adds find_random_virt_addr() to choose
a slot anywhere between LOAD_PHYSICAL_ADDR and KERNEL_IMAGE_SIZE.
Since this address is virtual, not physical, we can place the kernel
anywhere in this region, as long as it is aligned and (in the case of
kernel being larger than the slot size) placed with enough room to load
the entire kernel image.

For clarity and readability, find_random_addr() is renamed to
find_random_phys_addr() and has "size" renamed to "image_size" to match
find_random_virt_addr().

Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote changelog, refactored slot calculation for readability. ]
[ Renamed find_random_phys_addr() and size argument. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-6-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:06 +02:00
Kees Cook
06486d6c97 x86/KASLR: Return earliest overlap when avoiding regions
In preparation for being able to detect where to split up contiguous
memory regions that overlap with memory regions to avoid, we need to
pass back what the earliest overlapping region was. This modifies the
overlap checker to return that information.

Based on a separate mem_min_overlap() implementation by Baoquan He.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-5-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:04 +02:00
Baoquan He
c401cf1524 x86/KASLR: Add 'struct slot_area' to manage random_addr slots
In order to support KASLR moving the kernel anywhere in physical memory
(which could be up to 64TB), we need to handle counting the potential
randomization locations in a more efficient manner.

In the worst case with 64TB, there could be roughly 32 * 1024 * 1024
randomization slots if CONFIG_PHYSICAL_ALIGN is 0x1000000. Currently
the starting address of candidate positions is stored into the slots[]
array, one at a time. This method would cost too much memory and it's
also very inefficient to get and save the slot information into the slot
array one by one.

This patch introduces 'struct slot_area' to manage each contiguous region
of randomization slots. Each slot_area will contain the starting address
and how many available slots are in this area. As with the original code,
the slot_areas[] will avoid the mem_avoid[] regions.

Since setup_data is a linked list, it could contain an unknown number
of memory regions to be avoided, which could cause us to fragment
the contiguous memory that the slot_area array is tracking. In normal
operation this level of fragmentation will be extremely rare, but we
choose a suitably large value (100) for the array. If setup_data forces
the slot_area array to become highly fragmented and there are more
slots available beyond the first 100 found, the rest will be ignored
for KASLR selection.

The function store_slot_info() is used to calculate the number of slots
available in the passed-in memory region and stores it into slot_areas[]
after adjusting for alignment and size requirements.

Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote changelog, squashed with new functions. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:04 +02:00
Kees Cook
cb18ef0da2 x86/boot: Add missing file header comments
There were some files with missing header comments. Since they are
included from both compressed and regular kernels, make note of that.
Also corrects a typo in the mem_avoid comments.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:03 +02:00
Kees Cook
434a6c9f90 x86/KASLR: Initialize mapping_info every time
As it turns out, mapping_info DOES need to be initialized every
time, because pgt_data address could be changed during kernel
relocation. So it can not be build time assigned.

Without this, page tables were not being corrected updated, which
could cause reboots when a physical address beyond 2G was chosen.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462825332-10505-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:02 +02:00
Borislav Petkov
36a39ac967 x86/boot: Comment what finalize_identity_maps() does
So it is not really obvious that finalize_identity_maps() doesn't do any
finalization but it *actually* writes CR3 with the ident PGD. Comment
that at the call site.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: bhe@redhat.com
Cc: dyoung@redhat.com
Cc: jkosina@suse.cz
Cc: linux-tip-commits@vger.kernel.org
Cc: luto@kernel.org
Cc: vgoyal@redhat.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20160507100541.GA24613@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-10 10:12:02 +02:00
Kees Cook
3a94707d7a x86/KASLR: Build identity mappings on demand
Currently KASLR only supports relocation in a small physical range (from
16M to 1G), due to using the initial kernel page table identity mapping.
To support ranges above this, we need to have an identity mapping for the
desired memory range before we can decompress (and later run) the kernel.

32-bit kernels already have the needed identity mapping. This patch adds
identity mappings for the needed memory ranges on 64-bit kernels. This
happens in two possible boot paths:

If loaded via startup_32(), we need to set up the needed identity map.

If loaded from a 64-bit bootloader, the bootloader will have already
set up an identity mapping, and we'll start via the compressed kernel's
startup_64(). In this case, the bootloader's page tables need to be
avoided while selecting the new uncompressed kernel location. If not,
the decompressor could overwrite them during decompression.

To accomplish this, we could walk the pagetable and find every page
that is used, and add them to mem_avoid, but this needs extra code and
will require increasing the size of the mem_avoid array.

Instead, we can create a new set of page tables for our own identity
mapping instead. The pages for the new page table will come from the
_pagetable section of the compressed kernel, which means they are
already contained by in mem_avoid array. To do this, we reuse the code
from the uncompressed kernel's identity mapping routines.

The _pgtable will be shared by both the 32-bit and 64-bit paths to reduce
init_size, as now the compressed kernel's _rodata to _end will contribute
to init_size.

To handle the possible mappings, we need to increase the existing page
table buffer size:

When booting via startup_64(), we need to cover the old VO, params,
cmdline and uncompressed kernel. In an extreme case we could have them
all beyond the 512G boundary, which needs (2+2)*4 pages with 2M mappings.
And we'll need 2 for first 2M for VGA RAM. One more is needed for level4.
This gets us to 19 pages total.

When booting via startup_32(), KASLR could move the uncompressed kernel
above 4G, so we need to create extra identity mappings, which should only
need (2+2) pages at most when it is beyond the 512G boundary. So 19
pages is sufficient for this case as well.

The resulting BOOT_*PGT_SIZE defines use the "_SIZE" suffix on their
names to maintain logical consistency with the existing BOOT_HEAP_SIZE
and BOOT_STACK_SIZE defines.

This patch is based on earlier patches from Yinghai Lu and Baoquan He.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462572095-11754-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07 07:38:39 +02:00
Kees Cook
ed09acde44 x86/KASLR: Improve comments around the mem_avoid[] logic
This attempts to improve the comments that describe how the memory
range used for decompression is avoided. Additionally uses an enum
instead of raw numbers for the mem_avoid[] indexing.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20160506194459.GA16480@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07 07:38:38 +02:00
Borislav Petkov
549f90db68 x86/boot: Simplify pointer casting in choose_random_location()
Pass them down as 'unsigned long' directly and get rid of more casting and
assignments.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: bhe@redhat.com
Cc: dyoung@redhat.com
Cc: linux-tip-commits@vger.kernel.org
Cc: luto@kernel.org
Cc: vgoyal@redhat.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20160506115015.GI24044@pd.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-07 07:38:38 +02:00
Yinghai Lu
9dc1969c24 x86/KASLR: Consolidate mem_avoid[] entries
The mem_avoid[] array is used to track positions that should be avoided (like
the compressed kernel, decompression code, etc) when selecting a memory
position for the randomly relocated kernel. Since ZO is now at the end of
the decompression buffer and the decompression code (and its heap and
stack) are at the front, we can safely consolidate the decompression entry,
the heap entry, and the stack entry. The boot_params memory, however, could
be elsewhere, so it should be explicitly included.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rwrote changelog, cleaned up code comments. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462486436-3707-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 09:00:59 +02:00
Kees Cook
2bc1cd39fa x86/boot: Clean up pointer casting
Currently extract_kernel() defines the input and output buffer pointers
as "unsigned char *" since that's effectively what they are. It passes
these to the decompressor routine and to the ELF parser, which both
logically deal with buffer pointers too. There is some casting ("unsigned
long") done to validate the numerical value of the pointers, but it is
relatively limited.

However, choose_random_location() operates almost exclusively on the
numerical representation of these pointers, so it ended up carrying
a lot of "unsigned long" casts. With the future physical/virtual split
these casts were going to multiply, so this attempts to solve the
problem by doing all the casting in choose_random_location()'s entry
and return instead of through-out the code. Adjusts argument names to
be more meaningful, and changes one us of "choice" to "output" to make
the future physical/virtual split more clear (i.e. "choice" should be
strictly a function return value and not used as an intermediate).

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462486436-3707-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 09:00:59 +02:00
Kees Cook
00ec2c3703 x86/boot: Warn on future overlapping memcpy() use
If an overlapping memcpy() is ever attempted, we should at least report
it, in case it might lead to problems, so it could be changed to a
memmove() call instead.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1462229461-3370-3-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-03 08:15:58 +02:00
Kees Cook
dc425a6e14 x86/boot: Extract error reporting functions
Currently to use warn(), a caller would need to include misc.h. However,
this means they would get the (unavailable during compressed boot)
gcc built-in memcpy family of functions. But since string.c is defining
these memcpy functions for use by misc.c, we end up in a weird circular
dependency.

To break this loop, move the error reporting functions outside of misc.c
with their own header so that they can be independently included by
other sources. Since the screen-writing routines use memmove(), keep the
low-level *_putstr() functions in misc.c.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Lasse Collin <lasse.collin@tukaani.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1462229461-3370-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-03 08:15:58 +02:00
Yinghai Lu
4abf061bf8 x86/boot: Correctly bounds-check relocations
Relocation handling performs bounds checking on the resulting calculated
addresses. The existing code uses output_len (VO size plus relocs size) as
the max address. This is not right since the max_addr check should stop at
the end of VO and exclude bss, brk, etc, which follows.  The valid range
should be VO [_text, __bss_start] in the loaded physical address space.

This patch adds an export for __bss_start in voffset.h and uses it to
set the correct limit for max_addr.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Rewrote the changelog. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-7-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:03:30 +02:00
Yinghai Lu
4d2d542482 x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size'
Since 'run_size' is now calculated in misc.c, the old script and associated
argument passing is no longer needed. This patch removes them, and renames
'run_size' to the more descriptive 'kernel_total_size'.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog, renamed 'run_size' to 'kernel_total_size' ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-6-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:03:30 +02:00
Yinghai Lu
67b6662559 x86/boot: Fix "run_size" calculation
Currently, the "run_size" variable holds the total kernel size
(size of code plus brk and bss) and is calculated via the shell script
arch/x86/tools/calc_run_size.sh. It gets the file offset and mem size
of the .bss and .brk sections from the vmlinux, and adds them as follows:

  run_size = $(( $offsetA + $sizeA + $sizeB ))

However, this is not correct (it is too large). To illustrate, here's
a walk-through of the script's calculation, compared to the correct way
to find it.

First, offsetA is found as the starting address of the first .bss or
.brk section seen in the ELF file. The sizeA and sizeB values are the
respective section sizes.

 [bhe@x1 linux]$ objdump -h vmlinux

 vmlinux:     file format elf64-x86-64

 Sections:
 Idx Name    Size      VMA               LMA               File off  Algn
  27 .bss    00170000  ffffffff81ec8000  0000000001ec8000  012c8000  2**12
             ALLOC
  28 .brk    00027000  ffffffff82038000  0000000002038000  012c8000  2**0
             ALLOC

Here, offsetA is 0x012c8000, with sizeA at 0x00170000 and sizeB at
0x00027000. The resulting run_size is 0x145f000:

 0x012c8000 + 0x00170000 + 0x00027000 = 0x145f000

However, if we instead examine the ELF LOAD program headers, we see a
different picture.

 [bhe@x1 linux]$ readelf -l vmlinux

 Elf file type is EXEC (Executable file)
 Entry point 0x1000000
 There are 5 program headers, starting at offset 64

 Program Headers:
  Type        Offset             VirtAddr           PhysAddr
              FileSiz            MemSiz              Flags  Align
  LOAD        0x0000000000200000 0xffffffff81000000 0x0000000001000000
              0x0000000000b5e000 0x0000000000b5e000  R E    200000
  LOAD        0x0000000000e00000 0xffffffff81c00000 0x0000000001c00000
              0x0000000000145000 0x0000000000145000  RW     200000
  LOAD        0x0000000001000000 0x0000000000000000 0x0000000001d45000
              0x0000000000018158 0x0000000000018158  RW     200000
  LOAD        0x000000000115e000 0xffffffff81d5e000 0x0000000001d5e000
              0x000000000016a000 0x0000000000301000  RWE    200000
  NOTE        0x000000000099bcac 0xffffffff8179bcac 0x000000000179bcac
              0x00000000000001bc 0x00000000000001bc         4

 Section to Segment mapping:
  Segment Sections...
   00     .text .notes __ex_table .rodata __bug_table .pci_fixup .tracedata
          __ksymtab __ksymtab_gpl __ksymtab_strings __init_rodata __param
          __modver
   01     .data .vvar
   02     .data..percpu
   03     .init.text .init.data .x86_cpu_dev.init .parainstructions
          .altinstructions .altinstr_replacement .iommu_table .apicdrivers
          .exit.text .smp_locks .bss .brk
   04     .notes

As mentioned, run_size needs to be the size of the running kernel
including .bss and .brk. We can see from the Section/Segment mapping
above that .bss and .brk are included in segment 03 (which corresponds
to the final LOAD program header). To find the run_size, we calculate
the end of the LOAD segment from its PhysAddr start (0x0000000001d5e000)
and its MemSiz (0x0000000000301000), minus the physical load address of
the kernel (the first LOAD segment's PhysAddr: 0x0000000001000000). The
resulting run_size is 0x105f000:

 0x0000000001d5e000 + 0x0000000000301000 - 0x0000000001000000 = 0x105f000

So, from this we can see that the existing run_size calculation is
0x400000 too high. And, as it turns out, the correct run_size is
actually equal to VO_end - VO_text, which is certainly easier to calculate.
_end: 0xffffffff8205f000
_text:0xffffffff81000000

 0xffffffff8205f000 - 0xffffffff81000000 = 0x105f000

As a result, run_size is a simple constant, so we don't need to pass it
around; we already have voffset.h for such things. We can share voffset.h
between misc.c and header.S instead of getting run_size in other ways.
This patch moves voffset.h creation code to boot/compressed/Makefile,
and switches misc.c to use the VO_end - VO_text calculation for run_size.

Dependence before:

 boot/header.S ==> boot/voffset.h ==> vmlinux
 boot/header.S ==> compressed/vmlinux ==> compressed/misc.c

Dependence after:

 boot/header.S ==> compressed/vmlinux ==> compressed/misc.c ==> boot/voffset.h ==> vmlinux

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Junjie Mao <eternal.n08@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Fixes: e6023367d7 ("x86, kaslr: Prevent .bss from overlaping initrd")
Link: http://lkml.kernel.org/r/1461888548-32439-5-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:03:30 +02:00
Yinghai Lu
d607251ba9 x86/boot: Calculate decompression size during boot not build
Currently z_extract_offset is calculated in boot/compressed/mkpiggy.c.
This doesn't work well because mkpiggy.c doesn't know the details of the
decompressor in use. As a result, it can only make an estimation, which
has risks:

 - output + output_len (VO) could be much bigger than input + input_len
   (ZO). In this case, the decompressed kernel plus relocs could overwrite
   the decompression code while it is running.

 - The head code of ZO could be bigger than z_extract_offset. In this case
   an overwrite could happen when the head code is running to move ZO to
   the end of buffer. Though currently the size of the head code is very
   small it's still a potential risk. Since there is no rule to limit the
   size of the head code of ZO, it runs the risk of suddenly becoming a
   (hard to find) bug.

Instead, this moves the z_extract_offset calculation into header.S, and
makes adjustments to be sure that the above two cases can never happen,
and further corrects the comments describing the calculations.

Since we have (in the previous patch) made ZO always be located against
the end of decompression buffer, z_extract_offset is only used here to
calculate an appropriate buffer size (INIT_SIZE), and is not longer used
elsewhere. As such, it can be removed from voffset.h.

Additionally clean up #if/#else #define to improve readability.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog and comments. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-4-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:03:29 +02:00
Yinghai Lu
974f221c84 x86/boot: Move compressed kernel to the end of the decompression buffer
This change makes later calculations about where the kernel is located
easier to reason about. To better understand this change, we must first
clarify what 'VO' and 'ZO' are. These values were introduced in commits
by hpa:

  77d1a49995 ("x86, boot: make symbols from the main vmlinux available")
  37ba7ab5e3 ("x86, boot: make kernel_alignment adjustable; new bzImage fields")

Specifically:

All names prefixed with 'VO_':

 - relate to the uncompressed kernel image

 - the size of the VO image is: VO__end-VO__text ("VO_INIT_SIZE" define)

All names prefixed with 'ZO_':

 - relate to the bootable compressed kernel image (boot/compressed/vmlinux),
   which is composed of the following memory areas:
     - head text
     - compressed kernel (VO image and relocs table)
     - decompressor code

 - the size of the ZO image is: ZO__end - ZO_startup_32 ("ZO_INIT_SIZE" define, though see below)

The 'INIT_SIZE' value is used to find the larger of the two image sizes:

 #define ZO_INIT_SIZE    (ZO__end - ZO_startup_32 + ZO_z_extract_offset)
 #define VO_INIT_SIZE    (VO__end - VO__text)

 #if ZO_INIT_SIZE > VO_INIT_SIZE
 # define INIT_SIZE ZO_INIT_SIZE
 #else
 # define INIT_SIZE VO_INIT_SIZE
 #endif

The current code uses extract_offset to decide where to position the
copied ZO (i.e. ZO starts at extract_offset). (This is why ZO_INIT_SIZE
currently includes the extract_offset.)

Why does z_extract_offset exist? It's needed because we are trying to minimize
the amount of RAM used for the whole act of creating an uncompressed, executable,
properly relocation-linked kernel image in system memory. We do this so that
kernels can be booted on even very small systems.

To achieve the goal of minimal memory consumption we have implemented an in-place
decompression strategy: instead of cleanly separating the VO and ZO images and
also allocating some memory for the decompression code's runtime needs, we instead
create this elaborate layout of memory buffers where the output (decompressed)
stream, as it progresses, overlaps with and destroys the input (compressed)
stream. This can only be done safely if the ZO image is placed to the end of the
VO range, plus a certain amount of safety distance to make sure that when the last
bytes of the VO range are decompressed, the compressed stream pointer is safely
beyond the end of the VO range.

z_extract_offset is calculated in arch/x86/boot/compressed/mkpiggy.c during
the build process, at a point when we know the exact compressed and
uncompressed size of the kernel images and can calculate this safe minimum
offset value. (Note that the mkpiggy.c calculation is not perfect, because
we don't know the decompressor used at that stage, so the z_extract_offset
calculation is necessarily imprecise and is mostly based on gzip internals -
we'll improve that in the next patch.)

When INIT_SIZE is bigger than VO_INIT_SIZE (uncommon but possible),
the copied ZO occupies the memory from extract_offset to the end of
decompression buffer. It overlaps with the soon-to-be-uncompressed kernel
like this:

                            |-----compressed kernel image------|
                            V                                  V
0                       extract_offset                      +INIT_SIZE
|-----------|---------------|-------------------------|--------|
            |               |                         |        |
          VO__text      startup_32 of ZO          VO__end    ZO__end
            ^                                         ^
            |-------uncompressed kernel image---------|

When INIT_SIZE is equal to VO_INIT_SIZE (likely) there's still space
left from end of ZO to the end of decompressing buffer, like below.

                            |-compressed kernel image-|
                            V                         V
0                       extract_offset                      +INIT_SIZE
|-----------|---------------|-------------------------|--------|
            |               |                         |        |
          VO__text      startup_32 of ZO          ZO__end    VO__end
            ^                                                  ^
            |------------uncompressed kernel image-------------|

To simplify calculations and avoid special cases, it is cleaner to
always place the compressed kernel image in memory so that ZO__end
is at the end of the decompression buffer, instead of placing t at
the start of extract_offset as is currently done.

This patch adds BP_init_size (which is the INIT_SIZE as passed in from
the boot_params) into asm-offsets.c to make it visible to the assembly
code.

Then when moving the ZO, it calculates the starting position of
the copied ZO (via BP_init_size and the ZO run size) so that the VO__end
will be at the end of the decompression buffer. To make the position
calculation safe, the end of ZO is page aligned (and a comment is added
to the existing VO alignment for good measure).

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Rewrote changelog and comments. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-3-git-send-email-keescook@chromium.org
[ Rewrote the changelog some more. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:03:29 +02:00
Baoquan He
6f9af75faa x86/KASLR: Handle kernel relocations above 2G correctly
When processing the relocation table, the offset used to calculate the
relocation is an 'int'. This is sufficient for calculating the physical
address of the relocs entry on 32-bit systems and on 64-bit systems when
the relocation is under 2G.

To handle relocations above 2G (seen in situations like kexec, netboot, etc),
this offset needs to be calculated using a 'long' to avoid wrapping and
miscalculating the relocation.

Signed-off-by: Baoquan He <bhe@redhat.com>
[ Rewrote the changelog. ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1461888548-32439-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 09:58:26 +02:00