32-bit does not have GB pages, so don't bother checking for them. Using
the IS_ENABLED() macro allows the compiler to completely remove the
gb_huge_pages code.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-12-nivedita@alum.mit.edu
Clip the start and end of the region to minimum and mem_limit prior to
the loop. region.start can only increase during the loop, so raising it
to minimum before the loop is enough.
A region that becomes empty due to this will get checked in
the first iteration of the loop.
Drop the check for overlap extending beyond the end of the region. This
will get checked in the next loop iteration anyway.
Rename end to region_end for symmetry with region.start.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-10-nivedita@alum.mit.edu
region.size can be trimmed to store the portion of the region before the
overlap, instead of a separate mem_vector variable.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-9-nivedita@alum.mit.edu
In case of an overlap, the beginning of the region should be used even
if it is exactly image_size, not just strictly larger.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200728225722.67457-6-nivedita@alum.mit.edu
On 64-bit, the kernel must be placed below MAXMEM (64TiB with 4-level
paging or 4PiB with 5-level paging). This is currently not enforced by
KASLR, which thus implicitly relies on physical memory being limited to
less than 64TiB.
On 32-bit, the limit is KERNEL_IMAGE_SIZE (512MiB). This is enforced by
special checks in __process_mem_region().
Initialize mem_limit to the maximum (depending on architecture), instead
of ULLONG_MAX, and make sure the command-line arguments can only
decrease it. This makes the enforcement explicit on 64-bit, and
eliminates the 32-bit specific checks to keep the kernel below 512M.
Check upfront to make sure the minimum address is below the limit before
doing any work.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200727230801.3468620-5-nivedita@alum.mit.edu
Since commit:
0982adc746 ("x86/boot/KASLR: Work around firmware bugs by excluding EFI_BOOT_SERVICES_* and EFI_LOADER_* from KASLR's choice")
process_efi_entries() will return true if we have an EFI memmap, not just
if it contained EFI_MEMORY_MORE_RELIABLE regions.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200727230801.3468620-4-nivedita@alum.mit.edu
Drop the warning on seeing "--" in handle_mem_options(). This will trigger
whenever one of the memory options is present in the command line
together with "--", but there's no problem if that is the case.
Replace goto with break.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200727230801.3468620-3-nivedita@alum.mit.edu
Handle the possibility that the command line is NULL.
Replace open-coded strlen with a function call.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200727230801.3468620-2-nivedita@alum.mit.edu
- Update the ACPICA code in the kernel to upstream revision 20191018
including:
* Fixes for Clang warnings (Bob Moore).
* Fix for possible overflow in get_tick_count() (Bob Moore).
* Introduction of acpi_unload_table() (Bob Moore).
* Debugger and utilities updates (Erik Schmauss).
* Fix for unloading tables loaded via configfs (Nikolaus Voss).
- Add support for EFI specific purpose memory to optionally allow
either application-exclusive or core-kernel-mm managed access to
differentiated memory (Dan Williams).
- Fix and clean up processing of the HMAT table (Brice Goglin,
Qian Cai, Tao Xu).
- Update the ACPI EC driver to make it work on systems with
hardware-reduced ACPI (Daniel Drake).
- Always build in support for the Generic Event Device (GED) to
allow one kernel binary to work both on systems with full
hardware ACPI and hardware-reduced ACPI (Arjan van de Ven).
- Fix the table unload mechanism to unregister platform devices
created when the given table was loaded (Andy Shevchenko).
- Rework the lid blacklist handling in the button driver and add
more lid quirks to it (Hans de Goede).
- Improve ACPI-based device enumeration for some platforms based
on Intel BayTrail SoCs (Hans de Goede).
- Add an OpRegion driver for the Cherry Trail Crystal Cove PMIC
and prevent handlers from being registered for unhandled PMIC
OpRegions (Hans de Goede).
- Unify ACPI _HID/_UID matching (Andy Shevchenko).
- Clean up documentation and comments (Cao jin, James Pack, Kacper
Piwiński).
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Merge tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki:
"These update the ACPICA code in the kernel to upstream revision
20191018, add support for EFI specific purpose memory, update the ACPI
EC driver to make it work on systems with hardware-reduced ACPI,
improve ACPI-based device enumeration for some platforms, rework the
lid blacklist handling in the button driver and add more lid quirks to
it, unify ACPI _HID/_UID matching, fix assorted issues and clean up
the code and documentation.
Specifics:
- Update the ACPICA code in the kernel to upstream revision 20191018
including:
* Fixes for Clang warnings (Bob Moore)
* Fix for possible overflow in get_tick_count() (Bob Moore)
* Introduction of acpi_unload_table() (Bob Moore)
* Debugger and utilities updates (Erik Schmauss)
* Fix for unloading tables loaded via configfs (Nikolaus Voss)
- Add support for EFI specific purpose memory to optionally allow
either application-exclusive or core-kernel-mm managed access to
differentiated memory (Dan Williams)
- Fix and clean up processing of the HMAT table (Brice Goglin, Qian
Cai, Tao Xu)
- Update the ACPI EC driver to make it work on systems with
hardware-reduced ACPI (Daniel Drake)
- Always build in support for the Generic Event Device (GED) to allow
one kernel binary to work both on systems with full hardware ACPI
and hardware-reduced ACPI (Arjan van de Ven)
- Fix the table unload mechanism to unregister platform devices
created when the given table was loaded (Andy Shevchenko)
- Rework the lid blacklist handling in the button driver and add more
lid quirks to it (Hans de Goede)
- Improve ACPI-based device enumeration for some platforms based on
Intel BayTrail SoCs (Hans de Goede)
- Add an OpRegion driver for the Cherry Trail Crystal Cove PMIC and
prevent handlers from being registered for unhandled PMIC OpRegions
(Hans de Goede)
- Unify ACPI _HID/_UID matching (Andy Shevchenko)
- Clean up documentation and comments (Cao jin, James Pack, Kacper
Piwiński)"
* tag 'acpi-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (52 commits)
ACPI: OSI: Shoot duplicate word
ACPI: HMAT: use %u instead of %d to print u32 values
ACPI: NUMA: HMAT: fix a section mismatch
ACPI: HMAT: don't mix pxm and nid when setting memory target processor_pxm
ACPI: NUMA: HMAT: Register "soft reserved" memory as an "hmem" device
ACPI: NUMA: HMAT: Register HMAT at device_initcall level
device-dax: Add a driver for "hmem" devices
dax: Fix alloc_dax_region() compile warning
lib: Uplevel the pmem "region" ida to a global allocator
x86/efi: Add efi_fake_mem support for EFI_MEMORY_SP
arm/efi: EFI soft reservation to memblock
x86/efi: EFI soft reservation to E820 enumeration
efi: Common enable/disable infrastructure for EFI soft reservation
x86/efi: Push EFI_MEMMAP check into leaf routines
efi: Enumerate EFI_MEMORY_SP
ACPI: NUMA: Establish a new drivers/acpi/numa/ directory
ACPICA: Update version to 20191018
ACPICA: debugger: remove leading whitespaces when converting a string to a buffer
ACPICA: acpiexec: initialize all simple types and field units from user input
ACPICA: debugger: add field unit support for acpi_db_get_next_token
...
The setup_data is a bit awkward to use for extremely large data objects,
both because the setup_data header has to be adjacent to the data object
and because it has a 32-bit length field. However, it is important that
intermediate stages of the boot process have a way to identify which
chunks of memory are occupied by kernel data. Thus introduce an uniform
way to specify such indirect data as setup_indirect struct and
SETUP_INDIRECT type.
And finally bump setup_header version in arch/x86/boot/header.S.
Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Ross Philipson <ross.philipson@oracle.com>
Reviewed-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: ard.biesheuvel@linaro.org
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: dave.hansen@linux.intel.com
Cc: eric.snowberg@oracle.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juergen Gross <jgross@suse.com>
Cc: kanth.ghatraju@oracle.com
Cc: linux-doc@vger.kernel.org
Cc: linux-efi <linux-efi@vger.kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: rdunlap@infradead.org
Cc: ross.philipson@oracle.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Cc: xen-devel@lists.xenproject.org
Link: https://lkml.kernel.org/r/20191112134640.16035-4-daniel.kiper@oracle.com
Given that EFI_MEMORY_SP is platform BIOS policy decision for marking
memory ranges as "reserved for a specific purpose" there will inevitably
be scenarios where the BIOS omits the attribute in situations where it
is desired. Unlike other attributes if the OS wants to reserve this
memory from the kernel the reservation needs to happen early in init. So
early, in fact, that it needs to happen before e820__memblock_setup()
which is a pre-requisite for efi_fake_memmap() that wants to allocate
memory for the updated table.
Introduce an x86 specific efi_fake_memmap_early() that can search for
attempts to set EFI_MEMORY_SP via efi_fake_mem and update the e820 table
accordingly.
The KASLR code that scans the command line looking for user-directed
memory reservations also needs to be updated to consider
"efi_fake_mem=nn@ss:0x40000" requests.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
UEFI 2.8 defines an EFI_MEMORY_SP attribute bit to augment the
interpretation of the EFI Memory Types as "reserved for a specific
purpose".
The proposed Linux behavior for specific purpose memory is that it is
reserved for direct-access (device-dax) by default and not available for
any kernel usage, not even as an OOM fallback. Later, through udev
scripts or another init mechanism, these device-dax claimed ranges can
be reconfigured and hot-added to the available System-RAM with a unique
node identifier. This device-dax management scheme implements "soft" in
the "soft reserved" designation by allowing some or all of the
reservation to be recovered as typical memory. This policy can be
disabled at compile-time with CONFIG_EFI_SOFT_RESERVE=n, or runtime with
efi=nosoftreserve.
This patch introduces 2 new concepts at once given the entanglement
between early boot enumeration relative to memory that can optionally be
reserved from the kernel page allocator by default. The new concepts
are:
- E820_TYPE_SOFT_RESERVED: Upon detecting the EFI_MEMORY_SP
attribute on EFI_CONVENTIONAL memory, update the E820 map with this
new type. Only perform this classification if the
CONFIG_EFI_SOFT_RESERVE=y policy is enabled, otherwise treat it as
typical ram.
- IORES_DESC_SOFT_RESERVED: Add a new I/O resource descriptor for
a device driver to search iomem resources for application specific
memory. Teach the iomem code to identify such ranges as "Soft Reserved".
Note that the comment for do_add_efi_memmap() needed refreshing since it
seemed to imply that the efi map might overflow the e820 table, but that
is not an issue as of commit 7b6e4ba3cb "x86/boot/e820: Clean up the
E820_X_MAX definition" that removed the 128 entry limit for
e820__range_add().
A follow-on change integrates parsing of the ACPI HMAT to identify the
node and sub-range boundaries of EFI_MEMORY_SP designated memory. For
now, just identify and reserve memory of this type.
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
When compiling with -Wreturn-type, clang warns:
arch/x86/boot/compressed/kaslr.c:704:1: warning: control may reach end of
non-void function [-Wreturn-type]
This function's return statement should have been placed outside the
ifdeffed region. Move it there.
Fixes: 690eaa5320 ("x86/boot/KASLR: Limit KASLR to extract the kernel in immovable memory only")
Signed-off-by: Louis Taylor <louis@kragniz.eu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: bp@alien8.de
Cc: hpa@zytor.com
Cc: fanc.fnst@cn.fujitsu.com
Cc: bhe@redhat.com
Cc: kirill.shutemov@linux.intel.com
Cc: jflat@chromium.org
Link: https://lkml.kernel.org/r/20190302184929.28971-1-louis@kragniz.eu
When building randconfigs, one of the failures is:
ld: arch/x86/boot/compressed/kaslr.o: in function `choose_random_location':
kaslr.c:(.text+0xbf7): undefined reference to `count_immovable_mem_regions'
ld: kaslr.c:(.text+0xcbe): undefined reference to `immovable_mem'
make[2]: *** [arch/x86/boot/compressed/vmlinux] Error 1
because CONFIG_ACPI is not enabled in this particular .config but
CONFIG_MEMORY_HOTREMOVE is and count_immovable_mem_regions() is
unresolvable because it is defined in compressed/acpi.c which is the
compilation unit that depends on CONFIG_ACPI.
Add CONFIG_ACPI to the explicit dependencies for MEMORY_HOTREMOVE.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: x86@kernel.org
Link: https://lkml.kernel.org/r/20190205131033.9564-1-bp@alien8.de
KASLR may randomly choose a range which is located in movable memory
regions. As a result, this will break memory hotplug and make the
movable memory chosen by KASLR immovable.
Therefore, limit KASLR to choose memory regions in the immovable range
after consulting the SRAT table.
[ bp:
- Rewrite commit message.
- Trim comments.
]
Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: caoj.fnst@cn.fujitsu.com
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: indou.takao@jp.fujitsu.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: kasong@redhat.com
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: msys.mizuma@gmail.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-8-fanc.fnst@cn.fujitsu.com
Parse SRAT for the immovable memory regions and use that information to
control which offset KASLR selects so that it doesn't overlap with any
movable region.
[ bp:
- Move struct mem_vector where it is visible so that it builds.
- Correct comments.
- Rewrite commit message.
]
Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: <caoj.fnst@cn.fujitsu.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <indou.takao@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: <kasong@redhat.com>
Cc: <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <msys.mizuma@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20190123110850.12433-7-fanc.fnst@cn.fujitsu.com
It's not used by its sole user, so remove this unused functionality.
Also remove a stray unused variable that GCC didn't warn about for some reason.
Suggested-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Cc: 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: kirill.shutemov@linux.intel.com
Link: http://lkml.kernel.org/r/20180807015705.21697-1-fanc.fnst@cn.fujitsu.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To allow existing C code to be incorporated into the decompressor or the
UEFI stub, introduce a CPP macro that turns all EXPORT_SYMBOL_xxx
declarations into nops, and #define it in places where such exports are
undesirable. Note that this gets rid of a rather dodgy redefine of
linux/export.h's header guard.
Link: http://lkml.kernel.org/r/20180704083651.24360-3-ard.biesheuvel@linaro.org
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morris <james.morris@microsoft.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the following sparse warning:
arch/x86/boot/compressed/kaslr.c:102:20: warning: symbol 'mem_limit' was not declared. Should it be static?
Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/1532958273-47725-1-git-send-email-zhongjiang@huawei.com
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>
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>
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>
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>
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>
'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>
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>
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>
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>
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>
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>
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>
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
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
