Commit Graph

592 Commits

Author SHA1 Message Date
Josh Boyer
7f9b474c92 x86/efi-bgrt: Switch all pr_err() to pr_notice() for invalid BGRT
The promise of pretty boot splashes from firmware via BGRT was at
best only that; a promise.  The kernel diligently checks to make
sure the BGRT data firmware gives it is valid, and dutifully warns
the user when it isn't.  However, it does so via the pr_err log
level which seems unnecessary.  The user cannot do anything about
this and there really isn't an error on the part of Linux to
correct.

This lowers the log level by using pr_notice instead.  Users will
no longer have their boot process uglified by the kernel reminding
us that firmware can and often is broken when the 'quiet' kernel
parameter is specified.  Ironic, considering BGRT is supposed to
make boot pretty to begin with.

Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Môshe van der Sterre <me@moshe.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1462303781-8686-4-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-04 08:36:44 +02:00
Linus Torvalds
d88f48e128 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - fix hotplug bugs
   - fix irq live lock
   - fix various topology handling bugs
   - fix APIC ACK ordering
   - fix PV iopl handling
   - fix speling
   - fix/tweak memcpy_mcsafe() return value
   - fix fbcon bug
   - remove stray prototypes"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/msr: Remove unused native_read_tscp()
  x86/apic: Remove declaration of unused hw_nmi_is_cpu_stuck
  x86/oprofile/nmi: Add missing hotplug FROZEN handling
  x86/hpet: Use proper mask to modify hotplug action
  x86/apic/uv: Fix the hotplug notifier
  x86/apb/timer: Use proper mask to modify hotplug action
  x86/topology: Use total_cpus not nr_cpu_ids for logical packages
  x86/topology: Fix Intel HT disable
  x86/topology: Fix logical package mapping
  x86/irq: Cure live lock in fixup_irqs()
  x86/tsc: Prevent NULL pointer deref in calibrate_delay_is_known()
  x86/apic: Fix suspicious RCU usage in smp_trace_call_function_interrupt()
  x86/iopl: Fix iopl capability check on Xen PV
  x86/iopl/64: Properly context-switch IOPL on Xen PV
  selftests/x86: Add an iopl test
  x86/mm, x86/mce: Fix return type/value for memcpy_mcsafe()
  x86/video: Don't assume all FB devices are PCI devices
  arch/x86/irq: Purge useless handler declarations from hw_irq.h
  x86: Fix misspellings in comments
2016-03-24 09:47:32 -07:00
Linus Torvalds
24b5e20f11 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 are:

   - Use separate EFI page tables when executing EFI firmware code.
     This isolates the EFI context from the rest of the kernel, which
     has security and general robustness advantages.  (Matt Fleming)

   - Run regular UEFI firmware with interrupts enabled.  This is already
     the status quo under other OSs.  (Ard Biesheuvel)

   - Various x86 EFI enhancements, such as the use of non-executable
     attributes for EFI memory mappings.  (Sai Praneeth Prakhya)

   - Various arm64 UEFI enhancements.  (Ard Biesheuvel)

   - ... various fixes and cleanups.

  The separate EFI page tables feature got delayed twice already,
  because it's an intrusive change and we didn't feel confident about
  it - third time's the charm we hope!"

* 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  x86/mm/pat: Fix boot crash when 1GB pages are not supported by the CPU
  x86/efi: Only map kernel text for EFI mixed mode
  x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
  x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
  efi/arm*: Perform hardware compatibility check
  efi/arm64: Check for h/w support before booting a >4 KB granular kernel
  efi/arm: Check for LPAE support before booting a LPAE kernel
  efi/arm-init: Use read-only early mappings
  efi/efistub: Prevent __init annotations from being used
  arm64/vmlinux.lds.S: Handle .init.rodata.xxx and .init.bss sections
  efi/arm64: Drop __init annotation from handle_kernel_image()
  x86/mm/pat: Use _PAGE_GLOBAL bit for EFI page table mappings
  efi/runtime-wrappers: Run UEFI Runtime Services with interrupts enabled
  efi: Reformat GUID tables to follow the format in UEFI spec
  efi: Add Persistent Memory type name
  efi: Add NV memory attribute
  x86/efi: Show actual ending addresses in efi_print_memmap
  x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0
  efivars: Use to_efivar_entry
  efi: Runtime-wrapper: Get rid of the rtc_lock spinlock
  ...
2016-03-20 18:58:18 -07:00
Linus Torvalds
26660a4046 Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull 'objtool' stack frame validation from Ingo Molnar:
 "This tree adds a new kernel build-time object file validation feature
  (ONFIG_STACK_VALIDATION=y): kernel stack frame correctness validation.
  It was written by and is maintained by Josh Poimboeuf.

  The motivation: there's a category of hard to find kernel bugs, most
  of them in assembly code (but also occasionally in C code), that
  degrades the quality of kernel stack dumps/backtraces.  These bugs are
  hard to detect at the source code level.  Such bugs result in
  incorrect/incomplete backtraces most of time - but can also in some
  rare cases result in crashes or other undefined behavior.

  The build time correctness checking is done via the new 'objtool'
  user-space utility that was written for this purpose and which is
  hosted in the kernel repository in tools/objtool/.  The tool's (very
  simple) UI and source code design is shaped after Git and perf and
  shares quite a bit of infrastructure with tools/perf (which tooling
  infrastructure sharing effort got merged via perf and is already
  upstream).  Objtool follows the well-known kernel coding style.

  Objtool does not try to check .c or .S files, it instead analyzes the
  resulting .o generated machine code from first principles: it decodes
  the instruction stream and interprets it.  (Right now objtool supports
  the x86-64 architecture.)

  From tools/objtool/Documentation/stack-validation.txt:

   "The kernel CONFIG_STACK_VALIDATION option enables a host tool named
    objtool which runs at compile time.  It has a "check" subcommand
    which analyzes every .o file and ensures the validity of its stack
    metadata.  It enforces a set of rules on asm code and C inline
    assembly code so that stack traces can be reliable.

    Currently it only checks frame pointer usage, but there are plans to
    add CFI validation for C files and CFI generation for asm files.

    For each function, it recursively follows all possible code paths
    and validates the correct frame pointer state at each instruction.

    It also follows code paths involving special sections, like
    .altinstructions, __jump_table, and __ex_table, which can add
    alternative execution paths to a given instruction (or set of
    instructions).  Similarly, it knows how to follow switch statements,
    for which gcc sometimes uses jump tables."

  When this new kernel option is enabled (it's disabled by default), the
  tool, if it finds any suspicious assembly code pattern, outputs
  warnings in compiler warning format:

    warning: objtool: rtlwifi_rate_mapping()+0x2e7: frame pointer state mismatch
    warning: objtool: cik_tiling_mode_table_init()+0x6ce: call without frame pointer save/setup
    warning: objtool:__schedule()+0x3c0: duplicate frame pointer save
    warning: objtool:__schedule()+0x3fd: sibling call from callable instruction with changed frame pointer

  ... so that scripts that pick up compiler warnings will notice them.
  All known warnings triggered by the tool are fixed by the tree, most
  of the commits in fact prepare the kernel to be warning-free.  Most of
  them are bugfixes or cleanups that stand on their own, but there are
  also some annotations of 'special' stack frames for justified cases
  such entries to JIT-ed code (BPF) or really special boot time code.

  There are two other long-term motivations behind this tool as well:

   - To improve the quality and reliability of kernel stack frames, so
     that they can be used for optimized live patching.

   - To create independent infrastructure to check the correctness of
     CFI stack frames at build time.  CFI debuginfo is notoriously
     unreliable and we cannot use it in the kernel as-is without extra
     checking done both on the kernel side and on the build side.

  The quality of kernel stack frames matters to debuggability as well,
  so IMO we can merge this without having to consider the live patching
  or CFI debuginfo angle"

* 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (52 commits)
  objtool: Only print one warning per function
  objtool: Add several performance improvements
  tools: Copy hashtable.h into tools directory
  objtool: Fix false positive warnings for functions with multiple switch statements
  objtool: Rename some variables and functions
  objtool: Remove superflous INIT_LIST_HEAD
  objtool: Add helper macros for traversing instructions
  objtool: Fix false positive warnings related to sibling calls
  objtool: Compile with debugging symbols
  objtool: Detect infinite recursion
  objtool: Prevent infinite recursion in noreturn detection
  objtool: Detect and warn if libelf is missing and don't break the build
  tools: Support relative directory path for 'O='
  objtool: Support CROSS_COMPILE
  x86/asm/decoder: Use explicitly signed chars
  objtool: Enable stack metadata validation on 64-bit x86
  objtool: Add CONFIG_STACK_VALIDATION option
  objtool: Add tool to perform compile-time stack metadata validation
  x86/kprobes: Mark kretprobe_trampoline() stack frame as non-standard
  sched: Always inline context_switch()
  ...
2016-03-20 18:23:21 -07:00
Ingo Molnar
00f5268501 Merge branch 'x86/cleanups' into x86/urgent
Pull in some merge window leftovers.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-17 09:44:57 +01:00
Linus Torvalds
8ab84ef699 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 core platform updates from Ingo Molnar:
 "Intel Quark and Geode SoC platform updates"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/intel/quark: Drop IMR lock bit support
  x86/platform/intel/mid: Remove dead code
  x86/platform: Make platform/geode/net5501.c explicitly non-modular
  x86/platform: Make platform/geode/alix.c explicitly non-modular
  x86/platform: Make platform/geode/geos.c explicitly non-modular
  x86/platform: Make platform/intel-quark/imr_selftest.c explicitly non-modular
  x86/platform: Make platform/intel-quark/imr.c explicitly non-modular
2016-03-15 11:20:44 -07:00
Matt Fleming
452308de61 x86/efi: Fix boot crash by always mapping boot service regions into new EFI page tables
Some machines have EFI regions in page zero (physical address
0x00000000) and historically that region has been added to the e820
map via trim_bios_range(), and ultimately mapped into the kernel page
tables. It was not mapped via efi_map_regions() as one would expect.

Alexis reports that with the new separate EFI page tables some boot
services regions, such as page zero, are not mapped. This triggers an
oops during the SetVirtualAddressMap() runtime call.

For the EFI boot services quirk on x86 we need to memblock_reserve()
boot services regions until after SetVirtualAddressMap(). Doing that
while respecting the ownership of regions that may have already been
reserved by the kernel was the motivation behind this commit:

  7d68dc3f10 ("x86, efi: Do not reserve boot services regions within reserved areas")

That patch was merged at a time when the EFI runtime virtual mappings
were inserted into the kernel page tables as described above, and the
trick of setting ->numpages (and hence the region size) to zero to
track regions that should not be freed in efi_free_boot_services()
meant that we never mapped those regions in efi_map_regions(). Instead
we were relying solely on the existing kernel mappings.

Now that we have separate page tables we need to make sure the EFI
boot services regions are mapped correctly, even if someone else has
already called memblock_reserve(). Instead of stashing a tag in
->numpages, set the EFI_MEMORY_RUNTIME bit of ->attribute. Since it
generally makes no sense to mark a boot services region as required at
runtime, it's pretty much guaranteed the firmware will not have
already set this bit.

For the record, the specific circumstances under which Alexis
triggered this bug was that an EFI runtime driver on his machine was
responding to the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event during
SetVirtualAddressMap().

The event handler for this driver looks like this,

  sub rsp,0x28
  lea rdx,[rip+0x2445] # 0xaa948720
  mov ecx,0x4
  call func_aa9447c0  ; call to ConvertPointer(4, & 0xaa948720)
  mov r11,QWORD PTR [rip+0x2434] # 0xaa948720
  xor eax,eax
  mov BYTE PTR [r11+0x1],0x1
  add rsp,0x28
  ret

Which is pretty typical code for an EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE
handler. The "mov r11, QWORD PTR [rip+0x2424]" was the faulting
instruction because ConvertPointer() was being called to convert the
address 0x0000000000000000, which when converted is left unchanged and
remains 0x0000000000000000.

The output of the oops trace gave the impression of a standard NULL
pointer dereference bug, but because we're accessing physical
addresses during ConvertPointer(), it wasn't. EFI boot services code
is stored at that address on Alexis' machine.

Reported-by: Alexis Murzeau <amurzeau@gmail.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Raphael Hertzog <hertzog@debian.org>
Cc: Roger Shimizu <rogershimizu@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1457695163-29632-2-git-send-email-matt@codeblueprint.co.uk
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=815125
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-03-12 16:57:45 +01:00
Josh Poimboeuf
c0dd671686 objtool: Mark non-standard object files and directories
Code which runs outside the kernel's normal mode of operation often does
unusual things which can cause a static analysis tool like objtool to
emit false positive warnings:

 - boot image
 - vdso image
 - relocation
 - realmode
 - efi
 - head
 - purgatory
 - modpost

Set OBJECT_FILES_NON_STANDARD for their related files and directories,
which will tell objtool to skip checking them.  It's ok to skip them
because they don't affect runtime stack traces.

Also skip the following code which does the right thing with respect to
frame pointers, but is too "special" to be validated by a tool:

 - entry
 - mcount

Also skip the test_nx module because it modifies its exception handling
table at runtime, which objtool can't understand.  Fortunately it's
just a test module so it doesn't matter much.

Currently objtool is the only user of OBJECT_FILES_NON_STANDARD, but it
might eventually be useful for other tools.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/366c080e3844e8a5b6a0327dc7e8c2b90ca3baeb.1456719558.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-29 08:35:02 +01:00
Adam Buchbinder
6a6256f9e0 x86: Fix misspellings in comments
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:44:58 +01:00
Josh Poimboeuf
779c433b8e x86/asm/efi: Create a stack frame in efi_call()
efi_call() is a callable non-leaf function which doesn't honor
CONFIG_FRAME_POINTER, which can result in bad stack traces.

Create a stack frame for it when CONFIG_FRAME_POINTER is enabled.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Bernd Petrovitsch <bernd@petrovitsch.priv.at>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris J Arges <chris.j.arges@canonical.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Pedro Alves <palves@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/2294b6fad60eea4cc862eddc8e98a1324e6eeeca.1453405861.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-24 08:35:43 +01:00
Bryan O'Donoghue
c637fa5294 x86/platform/intel/quark: Drop IMR lock bit support
Isolated Memory Regions support a lock bit. The lock bit in an IMR prevents
modification of the IMR until the core goes through a warm or cold reset.
The lock bit feature is not useful in the context of the kernel API and is
not really necessary since modification of IMRs is possible only from
ring-zero anyway. This patch drops support for IMR locks bits, it
simplifies the kernel API and removes an unnecessary and needlessly complex
feature.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andriy.shevchenko@linux.intel.com
Cc: boon.leong.ong@intel.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/1456190999-12685-3-git-send-email-pure.logic@nexus-software.ie
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-23 07:37:23 +01:00
Ingo Molnar
fb86780bf7 Merge branch 'x86/urgent' into x86/platform, to queue up dependent patch
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-23 07:36:46 +01:00
Bryan O'Donoghue
dd71a17b11 x86/platform/intel/quark: Change the kernel's IMR lock bit to false
Currently when setting up an IMR around the kernel's .text section we lock
that IMR, preventing further modification. While superficially this appears
to be the right thing to do, in fact this doesn't account for a legitimate
change in the memory map such as when executing a new kernel via kexec.

In such a scenario a second kernel can have a different size and location
to it's predecessor and can view some of the memory occupied by it's
predecessor as legitimately usable DMA RAM. If this RAM were then
subsequently allocated to DMA agents within the system it could conceivably
trigger an IMR violation.

This patch fixes the this potential situation by keeping the kernel's .text
section IMR lock bit false by default.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: boon.leong.ong@intel.com
Cc: paul.gortmaker@windriver.com
Link: http://lkml.kernel.org/r/1456190999-12685-2-git-send-email-pure.logic@nexus-software.ie
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-23 07:35:53 +01:00
Sai Praneeth
2ad510dc37 x86/efi: Only map kernel text for EFI mixed mode
The correct symbol to use when figuring out the size of the kernel
text is '_etext', not '_end' which is the symbol for the entire kernel
image includes data and debug sections.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-14-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22 08:26:28 +01:00
Sai Praneeth
6d0cc887d5 x86/efi: Map EFI_MEMORY_{XP,RO} memory region bits to EFI page tables
Now that we have EFI memory region bits that indicate which regions do
not need execute permission or read/write permission in the page tables,
let's use them.

We also check for EFI_NX_PE_DATA and only enforce the restrictive
mappings if it's present (to allow us to ignore buggy firmware that sets
bits it didn't mean to and to preserve backwards compatibility).

Instead of assuming that firmware would set appropriate attributes in
memory descriptor like EFI_MEMORY_RO for code and EFI_MEMORY_XP for
data, we can expect some firmware out there which might only set *type*
in memory descriptor to be EFI_RUNTIME_SERVICES_CODE or
EFI_RUNTIME_SERVICES_DATA leaving away attribute. This will lead to
improper mappings of EFI runtime regions. In order to avoid it, we check
attribute and type of memory descriptor to update mappings and moreover
Windows works this way.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Kees Cook <keescook@chromium.org>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-13-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22 08:26:28 +01:00
Sai Praneeth
15f003d207 x86/mm/pat: Don't implicitly allow _PAGE_RW in kernel_map_pages_in_pgd()
As part of the preparation for the EFI_MEMORY_RO flag added in the UEFI
2.5 specification, we need the ability to map pages in kernel page
tables without _PAGE_RW being set.

Modify kernel_map_pages_in_pgd() to require its callers to pass _PAGE_RW
if the pages need to be mapped read/write. Otherwise, we'll map the
pages as read-only.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Hugh Dickins <hughd@google.com>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1455712566-16727-12-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-22 08:26:28 +01:00
Alan
8f8e2aec99 x86/platform/intel/mid: Remove dead code
Neither ratio nor fsb are ever zero, so remove the 0 case.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
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: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-17 18:00:15 +01:00
Paul Gortmaker
605a46ee83 x86/platform: Make platform/geode/net5501.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

  arch/x86/Kconfig:config NET5501
  arch/x86/Kconfig:       bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modularity, so that when reading
the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philip Prindeville <philipp@redfish-solutions.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1455491396-30977-6-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-16 09:11:09 +01:00
Paul Gortmaker
52d856e881 x86/platform: Make platform/geode/alix.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

  arch/x86/Kconfig:config ALIX
  arch/x86/Kconfig:       bool "PCEngines ALIX System Support (LED setup)"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We replace module.h with moduleparam.h since the file does declare
some module parameters, and leaving them as such is currently the
easiest way to remain compatible with existing boot arg use cases.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Ed Wildgoose <kernel@wildgooses.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/1455491396-30977-5-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-16 09:11:09 +01:00
Paul Gortmaker
eb61aee743 x86/platform: Make platform/geode/geos.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

  arch/x86/Kconfig:config GEOS
  arch/x86/Kconfig:       bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modularity, so that when reading
the code there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

We also delete the MODULE_LICENSE tag etc. since all that information
is already contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Philip Prindeville <philipp@redfish-solutions.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1455491396-30977-4-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-16 09:11:09 +01:00
Paul Gortmaker
32ed42ad6c x86/platform: Make platform/intel-quark/imr_selftest.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

  arch/x86/Kconfig.debug:config DEBUG_IMR_SELFTEST
  arch/x86/Kconfig.debug:    bool "Isolated Memory Region self test"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
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/1455491396-30977-3-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-16 09:11:08 +01:00
Paul Gortmaker
7f5301b7e6 x86/platform: Make platform/intel-quark/imr.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

  drivers/platform/x86/Kconfig:config INTEL_IMR
  drivers/platform/x86/Kconfig:   bool "Intel Isolated Memory Region support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.

Also note that MODULE_DEVICE_TABLE is a no-op for non-modular code.

We also delete the MODULE_LICENSE tag etc. since all that information
was (or is now) contained at the top of the file in the comments.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
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/1455491396-30977-2-git-send-email-paul.gortmaker@windriver.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-16 09:11:08 +01:00
Robert Elliott
1e82b94790 x86/efi: Show actual ending addresses in efi_print_memmap
Adjust efi_print_memmap to print the real end address of each
range, not 1 byte beyond. This matches other prints like those
for SRAT and nosave memory.

While investigating grub persistent memory corruption issues, it
was helpful to make this table match the ending address
convention used by:
* the kernel's e820 table prints
	BIOS-e820: [mem 0x0000001680000000-0x0000001c7fffffff] reserved
* the kernel's nosave memory prints
	PM: Registered nosave memory: [mem 0x880000000-0xc7fffffff]
* the kernel's ACPI System Resource Affinity Table prints
	SRAT: Node 1 PXM 1 [mem 0x480000000-0x87fffffff]
* grub's lsmmap and lsefimmap commands
	reserved  0000001680000000-0000001c7fffffff 00600000     24GiB UC WC WT WB NV
* the UEFI shell's memmap command
	Reserved   000000007FC00000-000000007FFFFFFF 0000000000000400 0000000000000001

For example, if you grep all the various logs for c7fffffff, you
won't find the kernel's line if it uses c80000000.

Also, change the closing ) to ] to match the opening [.

old:
    efi: mem61: [Persistent Memory  |   |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c80000000) (16384MB)

new:
    efi: mem61: [Persistent Memory  |   |  |  |  |  |  |   |WB|WT|WC|UC] range=[0x0000000880000000-0x0000000c7fffffff] (16384MB)

Signed-off-by: Robert Elliott <elliott@hpe.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Leif Lindholm <leif.lindholm@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/1454364428-494-12-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:41:20 +01:00
Môshe van der Sterre
66dbe99cfe x86/efi/bgrt: Don't ignore the BGRT if the 'valid' bit is 0
Unintuitively, the BGRT graphic is apparently meant to be usable
if the valid bit in not set. The valid bit only conveys
uncertainty about the validity in relation to the screen state.

Windows 10 actually uses the BGRT image for its boot screen even
if not 'valid', for example when the user triggered the boot
menu. Because it is unclear if all firmwares will provide a
usable graphic in this case, we now look at the BMP magic number
as an additional check.

Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Môshe van der Sterre <me@moshe.nl>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: =?UTF-8?q?M=C3=B4she=20van=20der=20Sterre?= <me@moshe.nl>
Link: http://lkml.kernel.org/r/1454364428-494-10-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:41:19 +01:00
Ard Biesheuvel
ca0e30dcaa efi: Add nonblocking option to efi_query_variable_store()
The function efi_query_variable_store() may be invoked by
efivar_entry_set_nonblocking(), which itself takes care to only
call a non-blocking version of the SetVariable() runtime
wrapper. However, efi_query_variable_store() may call the
SetVariable() wrapper directly, as well as the wrapper for
QueryVariableInfo(), both of which could deadlock in the same
way we are trying to prevent by calling
efivar_entry_set_nonblocking() in the first place.

So instead, modify efi_query_variable_store() to use the
non-blocking variants of QueryVariableInfo() (and give up rather
than free up space if the available space is below
EFI_MIN_RESERVE) if invoked with the 'nonblocking' argument set
to true.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
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: 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/1454364428-494-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:31:04 +01:00
Ingo Molnar
03e075b38e Merge branch 'linus' into efi/core, to refresh the branch and to pick up recent fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-03 11:30:36 +01:00
Linus Torvalds
d517be5fcf Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A bit on the largish side due to a series of fixes for a regression in
  the x86 vector management which was introduced in 4.3.  This work was
  started in December already, but it took some time to fix all corner
  cases and a couple of older bugs in that area which were detected
  while at it

  Aside of that a few platform updates for intel-mid, quark and UV and
  two fixes for in the mm code:
   - Use proper types for pgprot values to avoid truncation
   - Prevent a size truncation in the pageattr code when setting page
     attributes for large mappings"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (21 commits)
  x86/mm/pat: Avoid truncation when converting cpa->numpages to address
  x86/mm: Fix types used in pgprot cacheability flags translations
  x86/platform/quark: Print boundaries correctly
  x86/platform/UV: Remove EFI memmap quirk for UV2+
  x86/platform/intel-mid: Join string and fix SoC name
  x86/platform/intel-mid: Enable 64-bit build
  x86/irq: Plug vector cleanup race
  x86/irq: Call irq_force_move_complete with irq descriptor
  x86/irq: Remove outgoing CPU from vector cleanup mask
  x86/irq: Remove the cpumask allocation from send_cleanup_vector()
  x86/irq: Clear move_in_progress before sending cleanup IPI
  x86/irq: Remove offline cpus from vector cleanup
  x86/irq: Get rid of code duplication
  x86/irq: Copy vectormask instead of an AND operation
  x86/irq: Check vector allocation early
  x86/irq: Reorganize the search in assign_irq_vector
  x86/irq: Reorganize the return path in assign_irq_vector
  x86/irq: Do not use apic_chip_data.old_domain as temporary buffer
  x86/irq: Validate that irq descriptor is still active
  x86/irq: Fix a race in x86_vector_free_irqs()
  ...
2016-01-31 16:17:19 -08:00
Matt Fleming
753b11ef8e x86/efi: Setup separate EFI page tables in kexec paths
The switch to using a new dedicated page table for EFI runtime
calls in commit commit 67a9108ed4 ("x86/efi: Build our own
page table structures") failed to take into account changes
required for the kexec code paths, which are unfortunately
duplicated in the EFI code.

Call the allocation and setup functions in
kexec_enter_virtual_mode() just like we do for
__efi_enter_virtual_mode() to avoid hitting NULL-pointer
dereferences when making EFI runtime calls.

At the very least, the call to efi_setup_page_tables() should
have existed for kexec before the following commit:

  67a9108ed4 ("x86/efi: Build our own page table structures")

Things just magically worked because we were actually using
the kernel's page tables that contained the required mappings.

Reported-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Tested-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@amacapital.net>
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: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453385519-11477-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-21 21:01:34 +01:00
Andy Shevchenko
22c43f36b5 x86/platform/quark: Print boundaries correctly
When we print values, such as @size, we have to understand that
it's derived from [begin .. end] as:

	size = end - begin + 1

On the opposite the @end is derived from the rest as:

	end = begin + size - 1

Correct the IMR code to print values correctly.

Note that @__end_rodata actually points to the next address
after the aligned .rodata section.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ong, Boon Leong <boon.leong.ong@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1453320821-64328-1-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-21 08:40:26 +01:00
Alex Thorlton
d394f2d9d8 x86/platform/UV: Remove EFI memmap quirk for UV2+
Commit a5d90c923b ("x86/efi: Quirk out SGI UV") added a quirk
to efi_apply_memmap_quirks to force SGI UV systems to fall back
to the old EFI memmap mechanism.  We have a BIOS fix for this
issue on all systems except for UV1.  This commit fixes up the
EFI quirk/MMR mapping code so that we only apply the special
case to UV1 hardware.

Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1449867585-189233-2-git-send-email-athorlton@sgi.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-19 11:58:56 +01:00
Andy Shevchenko
b000de5848 x86/platform/intel-mid: Join string and fix SoC name
Join string back to make grepping a bit easier. While here,
lowering case for Penwell SoC name in one case to be aligned
with the rest messages.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1452888668-147116-2-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-01-19 08:39:56 +01:00
Linus Torvalds
67990608c8 Power management and ACPI updates for v4.5-rc1
- Add a debugfs-based interface for interacting with the ACPICA's
    AML debugger introduced in the previous cycle and a new user
    space tool for that, fix some bugs related to the AML debugger
    and clean up the code in question (Lv Zheng, Dan Carpenter,
    Colin Ian King, Markus Elfring).
 
  - Update ACPICA to upstream revision 20151218 including a number
    of fixes and cleanups in the ACPICA core (Bob Moore, Lv Zheng,
    Labbe Corentin, Prarit Bhargava, Colin Ian King, David E Box,
    Rafael Wysocki).
 
    In particular, the previously added erroneous support for the
    _SUB object is dropped, the concatenate operator will support
    all ACPI objects now, the Debug Object handling is improved,
    the SuperName handling of parameters being control methods is
    fixed, the ObjectType operator handling is updated to follow
    ACPI 5.0A and the handling of CondRefOf and RefOf is updated
    accordingly, module-level code will be executed after loading
    each ACPI table now (instead of being run once after all tables
    containing AML have been loaded), the Operation Region handlers
    management is updated to fix some reported problems and a the
    ACPICA code in the kernel is more in line with the upstream
    now.
 
  - Update the ACPI backlight driver to provide information on
    whether or not it will generate key-presses for brightness
    change hotkeys and update some platform drivers (dell-wmi,
    thinkpad_acpi) to use that information to avoid sending double
    key-events to users pace for these, add new ACPI backlight
    quirks (Hans de Goede, Aaron Lu, Adrien Schildknecht).
 
  - Improve the ACPI handling of interrupt GPIOs (Christophe Ricard).
 
  - Fix the handling of the list of device IDs of device objects
    found in the ACPI namespace and add a helper for checking if
    there is a device object for a given device ID (Lukas Wunner).
 
  - Change the logic in the ACPI namespace scanning code to create
    struct acpi_device objects for all ACPI device objects found in
    the namespace even if _STA fails for them which helps to avoid
    device enumeration problems on Microsoft Surface 3 (Aaron Lu).
 
  - Add support for the APM X-Gene ACPI I2C device to the ACPI
    driver for AMD SoCs (Loc Ho).
 
  - Fix the long-standing issue with the DMA controller on Intel
    SoCs where ACPI tables have no power management support for
    the DMA controller itself, but it can be powered off automatically
    when the last (other) device on the SoC is powered off via ACPI
    and clean up the ACPI driver for Intel SoCs (acpi-lpss) after
    previous attempts to fix that problem (Andy Shevchenko).
 
  - Assorted ACPI fixes and cleanups (Andy Lutomirski, Colin Ian King,
    Javier Martinez Canillas, Ken Xue, Mathias Krause, Rafael Wysocki,
    Sinan Kaya).
 
  - Update the device properties framework for better handling of
    built-in properties, add support for built-in properties to
    the platform bus type, update the MFD subsystem's handling
    of device properties and add support for passing default
    configuration data as device properties to the intel-lpss MFD
    drivers, convert the designware I2C driver to use the unified
    device properties API and add a fallback mechanism for using
    default built-in properties if the platform firmware fails
    to provide the properties as expected by drivers (Andy Shevchenko,
    Mika Westerberg, Heikki Krogerus, Andrew Morton).
 
  - Add new Device Tree bindings to the Operating Performance Points
    (OPP) framework and update the exynos4412 DT binding accordingly,
    introduce debugfs support for the OPP framework (Viresh Kumar,
    Bartlomiej Zolnierkiewicz).
 
  - Migrate the mt8173 cpufreq driver to the new OPP bindings
    (Pi-Cheng Chen).
 
  - Update the cpufreq core to make the handling of governors
    more efficient, especially on systems where policy objects
    are shared between multiple CPUs (Viresh Kumar, Rafael Wysocki).
 
  - Fix cpufreq governor handling on configurations with
    CONFIG_HZ_PERIODIC set (Chen Yu).
 
  - Clean up the cpufreq core code related to the boost sysfs knob
    support and update the ACPI cpufreq driver accordingly (Rafael
    Wysocki).
 
  - Add a new cpufreq driver for ST platforms and corresponding
    Device Tree bindings (Lee Jones).
 
  - Update the intel_pstate driver to allow the P-state selection
    algorithm used by it to depend on the CPU ID of the processor it
    is running on, make it use a special P-state selection algorithm
    (with an IO wait time compensation tweak) on Atom CPUs based on
    the Airmont and Silvermont cores so as to reduce their energy
    consumption and improve intel_pstate documentation (Philippe
    Longepe, Srinivas Pandruvada).
 
  - Update the cpufreq-dt driver to support registering cooling
    devices that use the (P * V^2 * f) dynamic power draw formula
    where V is the voltage, f is the frequency and P is a constant
    coefficient provided by Device Tree and update the arm_big_little
    cpufreq driver to use that support (Punit Agrawal).
 
  - Assorted cpufreq driver (cpufreq-dt, qoriq, pcc-cpufreq,
    blackfin-cpufreq) updates (Andrzej Hajda, Hongtao Jia,
    Jacob Tanenbaum, Markus Elfring).
 
  - cpuidle core tweaks related to polling and measured_us
    calculation (Rik van Riel).
 
  - Removal of modularity from a few cpuidle drivers (clps711x,
    ux500, exynos) that cannot be built as modules in practice
    (Paul Gortmaker).
 
  - PM core update to prevent devices from being probed during
    system suspend/resume which is generally problematic and may
    lead to inconsistent behavior (Grygorii Strashko).
 
  - Assorted updates of the PM core and related code (Julia Lawall,
    Manuel Pégourié-Gonnard, Maruthi Bayyavarapu, Rafael Wysocki,
    Ulf Hansson).
 
  - PNP bus type updates (Christophe Le Roy, Heiner Kallweit).
 
  - PCI PM code cleanups (Jarkko Nikula, Julia Lawall).
 
  - cpupower tool updates (Jacob Tanenbaum, Thomas Renninger).
 
 /
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Merge tag 'pm+acpi-4.5-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull oower management and ACPI updates from Rafael Wysocki:
 "As far as the number of commits goes, ACPICA takes the lead this time,
  followed by cpufreq and the device properties framework changes.

  The most significant new feature is the debugfs-based interface to the
  ACPICA's AML debugger added in the previous cycle and a new user space
  tool for accessing it.

  On the cpufreq front, the core is updated to handle governors more
  efficiently, particularly on systems where a single cpufreq policy
  object is shared between multiple CPUs, and there are quite a few
  changes in drivers (intel_pstate, cpufreq-dt etc).

  The device properties framework is updated to handle built-in (ie
  included in the kernel itself) device properties better, among other
  things by adding a fallback mechanism that will allow drivers to
  provide default properties to be used in case the plaform firmware
  doesn't provide the properties expected by them.

  The Operating Performance Points (OPP) framework gets new DT bindings
  and debugfs support.

  A new cpufreq driver for ST platforms is added and the ACPI driver for
  AMD SoCs will now support the APM X-Gene ACPI I2C device.

  The rest is mostly fixes and cleanups all over.

  Specifics:

   - Add a debugfs-based interface for interacting with the ACPICA's AML
     debugger introduced in the previous cycle and a new user space tool
     for that, fix some bugs related to the AML debugger and clean up
     the code in question (Lv Zheng, Dan Carpenter, Colin Ian King,
     Markus Elfring).

   - Update ACPICA to upstream revision 20151218 including a number of
     fixes and cleanups in the ACPICA core (Bob Moore, Lv Zheng, Labbe
     Corentin, Prarit Bhargava, Colin Ian King, David E Box, Rafael
     Wysocki).

     In particular, the previously added erroneous support for the _SUB
     object is dropped, the concatenate operator will support all ACPI
     objects now, the Debug Object handling is improved, the SuperName
     handling of parameters being control methods is fixed, the
     ObjectType operator handling is updated to follow ACPI 5.0A and the
     handling of CondRefOf and RefOf is updated accordingly, module-
     level code will be executed after loading each ACPI table now
     (instead of being run once after all tables containing AML have
     been loaded), the Operation Region handlers management is updated
     to fix some reported problems and a the ACPICA code in the kernel
     is more in line with the upstream now.

   - Update the ACPI backlight driver to provide information on whether
     or not it will generate key-presses for brightness change hotkeys
     and update some platform drivers (dell-wmi, thinkpad_acpi) to use
     that information to avoid sending double key-events to users pace
     for these, add new ACPI backlight quirks (Hans de Goede, Aaron Lu,
     Adrien Schildknecht).

   - Improve the ACPI handling of interrupt GPIOs (Christophe Ricard).

   - Fix the handling of the list of device IDs of device objects found
     in the ACPI namespace and add a helper for checking if there is a
     device object for a given device ID (Lukas Wunner).

   - Change the logic in the ACPI namespace scanning code to create
     struct acpi_device objects for all ACPI device objects found in the
     namespace even if _STA fails for them which helps to avoid device
     enumeration problems on Microsoft Surface 3 (Aaron Lu).

   - Add support for the APM X-Gene ACPI I2C device to the ACPI driver
     for AMD SoCs (Loc Ho).

   - Fix the long-standing issue with the DMA controller on Intel SoCs
     where ACPI tables have no power management support for the DMA
     controller itself, but it can be powered off automatically when the
     last (other) device on the SoC is powered off via ACPI and clean up
     the ACPI driver for Intel SoCs (acpi-lpss) after previous attempts
     to fix that problem (Andy Shevchenko).

   - Assorted ACPI fixes and cleanups (Andy Lutomirski, Colin Ian King,
     Javier Martinez Canillas, Ken Xue, Mathias Krause, Rafael Wysocki,
     Sinan Kaya).

   - Update the device properties framework for better handling of
     built-in properties, add support for built-in properties to the
     platform bus type, update the MFD subsystem's handling of device
     properties and add support for passing default configuration data
     as device properties to the intel-lpss MFD drivers, convert the
     designware I2C driver to use the unified device properties API and
     add a fallback mechanism for using default built-in properties if
     the platform firmware fails to provide the properties as expected
     by drivers (Andy Shevchenko, Mika Westerberg, Heikki Krogerus,
     Andrew Morton).

   - Add new Device Tree bindings to the Operating Performance Points
     (OPP) framework and update the exynos4412 DT binding accordingly,
     introduce debugfs support for the OPP framework (Viresh Kumar,
     Bartlomiej Zolnierkiewicz).

   - Migrate the mt8173 cpufreq driver to the new OPP bindings (Pi-Cheng
     Chen).

   - Update the cpufreq core to make the handling of governors more
     efficient, especially on systems where policy objects are shared
     between multiple CPUs (Viresh Kumar, Rafael Wysocki).

   - Fix cpufreq governor handling on configurations with
     CONFIG_HZ_PERIODIC set (Chen Yu).

   - Clean up the cpufreq core code related to the boost sysfs knob
     support and update the ACPI cpufreq driver accordingly (Rafael
     Wysocki).

   - Add a new cpufreq driver for ST platforms and corresponding Device
     Tree bindings (Lee Jones).

   - Update the intel_pstate driver to allow the P-state selection
     algorithm used by it to depend on the CPU ID of the processor it is
     running on, make it use a special P-state selection algorithm (with
     an IO wait time compensation tweak) on Atom CPUs based on the
     Airmont and Silvermont cores so as to reduce their energy
     consumption and improve intel_pstate documentation (Philippe
     Longepe, Srinivas Pandruvada).

   - Update the cpufreq-dt driver to support registering cooling devices
     that use the (P * V^2 * f) dynamic power draw formula where V is
     the voltage, f is the frequency and P is a constant coefficient
     provided by Device Tree and update the arm_big_little cpufreq
     driver to use that support (Punit Agrawal).

   - Assorted cpufreq driver (cpufreq-dt, qoriq, pcc-cpufreq,
     blackfin-cpufreq) updates (Andrzej Hajda, Hongtao Jia, Jacob
     Tanenbaum, Markus Elfring).

   - cpuidle core tweaks related to polling and measured_us calculation
     (Rik van Riel).

   - Removal of modularity from a few cpuidle drivers (clps711x, ux500,
     exynos) that cannot be built as modules in practice (Paul
     Gortmaker).

   - PM core update to prevent devices from being probed during system
     suspend/resume which is generally problematic and may lead to
     inconsistent behavior (Grygorii Strashko).

   - Assorted updates of the PM core and related code (Julia Lawall,
     Manuel Pégourié-Gonnard, Maruthi Bayyavarapu, Rafael Wysocki, Ulf
     Hansson).

   - PNP bus type updates (Christophe Le Roy, Heiner Kallweit).

   - PCI PM code cleanups (Jarkko Nikula, Julia Lawall).

   - cpupower tool updates (Jacob Tanenbaum, Thomas Renninger)"

* tag 'pm+acpi-4.5-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (177 commits)
  PM / clk: don't leave clocks enabled when driver not bound
  i2c: dw: Add APM X-Gene ACPI I2C device support
  ACPI / APD: Add APM X-Gene ACPI I2C device support
  ACPI / LPSS: change 'does not have' to 'has' in comment
  Revert "dmaengine: dw: platform: provide platform data for Intel"
  dmaengine: dw: return immediately from IRQ when DMA isn't in use
  dmaengine: dw: platform: power on device on shutdown
  ACPI / LPSS: override power state for LPSS DMA device
  PM / OPP: Use snprintf() instead of sprintf()
  Documentation: cpufreq: intel_pstate: enhance documentation
  ACPI, PCI, irq: remove redundant check for null string pointer
  ACPI / video: driver must be registered before checking for keypresses
  cpufreq-dt: fix handling regulator_get_voltage() result
  cpufreq: governor: Fix negative idle_time when configured with CONFIG_HZ_PERIODIC
  PM / sleep: Add support for read-only sysfs attributes
  ACPI: Fix white space in a structure definition
  ACPI / SBS: fix inconsistent indenting inside if statement
  PNP: respect PNP_DRIVER_RES_DO_NOT_CHANGE when detaching
  ACPI / PNP: constify device IDs
  ACPI / PCI: Simplify acpi_penalize_isa_irq()
  ...
2016-01-12 20:25:09 -08:00
Matt Fleming
e2c90dd7e1 x86/efi-bgrt: Replace early_memremap() with memremap()
Môshe reported the following warning triggered on his machine since
commit 50a0cb5652 ("x86/efi-bgrt: Fix kernel panic when mapping BGRT
data"),

  [    0.026936] ------------[ cut here ]------------
  [    0.026941] WARNING: CPU: 0 PID: 0 at mm/early_ioremap.c:137 __early_ioremap+0x102/0x1bb()
  [    0.026941] Modules linked in:
  [    0.026944] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1 #2
  [    0.026945] Hardware name: Dell Inc. XPS 13 9343/09K8G1, BIOS A05 07/14/2015
  [    0.026946]  0000000000000000 900f03d5a116524d ffffffff81c03e60 ffffffff813a3fff
  [    0.026948]  0000000000000000 ffffffff81c03e98 ffffffff810a0852 00000000d7b76000
  [    0.026949]  0000000000000000 0000000000000001 0000000000000001 000000000000017c
  [    0.026951] Call Trace:
  [    0.026955]  [<ffffffff813a3fff>] dump_stack+0x44/0x55
  [    0.026958]  [<ffffffff810a0852>] warn_slowpath_common+0x82/0xc0
  [    0.026959]  [<ffffffff810a099a>] warn_slowpath_null+0x1a/0x20
  [    0.026961]  [<ffffffff81d8c395>] __early_ioremap+0x102/0x1bb
  [    0.026962]  [<ffffffff81d8c602>] early_memremap+0x13/0x15
  [    0.026964]  [<ffffffff81d78361>] efi_bgrt_init+0x162/0x1ad
  [    0.026966]  [<ffffffff81d778ec>] efi_late_init+0x9/0xb
  [    0.026968]  [<ffffffff81d58ff5>] start_kernel+0x46f/0x49f
  [    0.026970]  [<ffffffff81d58120>] ? early_idt_handler_array+0x120/0x120
  [    0.026972]  [<ffffffff81d58339>] x86_64_start_reservations+0x2a/0x2c
  [    0.026974]  [<ffffffff81d58485>] x86_64_start_kernel+0x14a/0x16d
  [    0.026977] ---[ end trace f9b3812eb8e24c58 ]---
  [    0.026978] efi_bgrt: Ignoring BGRT: failed to map image memory

early_memremap() has an upper limit on the size of mapping it can
handle which is ~200KB. Clearly the BGRT image on Môshe's machine is
much larger than that.

There's actually no reason to restrict ourselves to using the early_*
version of memremap() - the ACPI BGRT driver is invoked late enough in
boot that we can use the standard version, with the benefit that the
late version allows mappings of arbitrary size.

Reported-by: Môshe van der Sterre <me@moshe.nl>
Tested-by: Môshe van der Sterre <me@moshe.nl>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1450707172-12561-1-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-01-06 18:28:52 +01:00
Thomas Gleixner
98f9127690 * We don't need to carry our own formatting code in the esrt driver
because the kobject API can do that for us - Rasmus Villemoes
 
  * Update the arm64 file paths in Documentation/efi-stub.txt to match
    the current tree - Alan Ott
 
  * Consistently preface all print statements with "efi" arch/x86 so
    that it's more obvious to users reporting problems which statements
    in the kernel log are relevant for EFI - Matt Fleming
 
  * Fix a boot crash in the ACPI BGRT driver and delete
    efi_lookup_mapped_addr() since it's useless now that the EFI
    mappings *only* exist in the 'efi_pgd' page table. Instead we
    always early_memremap() the BGRT memory - Sai Praneeth Prakhya
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/efi

Pull efi changes from Matt Fleming:

 * We don't need to carry our own formatting code in the esrt driver
   because the kobject API can do that for us - Rasmus Villemoes

 * Update the arm64 file paths in Documentation/efi-stub.txt to match
   the current tree - Alan Ott

 * Consistently preface all print statements with "efi" arch/x86 so
   that it's more obvious to users reporting problems which statements
   in the kernel log are relevant for EFI - Matt Fleming

 * Fix a boot crash in the ACPI BGRT driver and delete
   efi_lookup_mapped_addr() since it's useless now that the EFI
   mappings *only* exist in the 'efi_pgd' page table. Instead we
   always early_memremap() the BGRT memory - Sai Praneeth Prakhya
2015-12-19 21:24:52 +01:00
Sai Praneeth
50a0cb5652 x86/efi-bgrt: Fix kernel panic when mapping BGRT data
Starting with this commit 35eb8b81edd4 ("x86/efi: Build our own page
table structures") efi regions have a separate page directory called
"efi_pgd". In order to access any efi region we have to first shift %cr3
to this page table. In the bgrt code we are trying to copy bgrt_header
and image, but these regions fall under "EFI_BOOT_SERVICES_DATA"
and to access these regions we have to shift %cr3 to efi_pgd and not
doing so will cause page fault as shown below.

[    0.251599] Last level dTLB entries: 4KB 64, 2MB 0, 4MB 0, 1GB 4
[    0.259126] Freeing SMP alternatives memory: 32K (ffffffff8230e000 - ffffffff82316000)
[    0.271803] BUG: unable to handle kernel paging request at fffffffefce35002
[    0.279740] IP: [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.286383] PGD 300f067 PUD 0
[    0.289879] Oops: 0000 [#1] SMP
[    0.293566] Modules linked in:
[    0.297039] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.4.0-rc1-eywa-eywa-built-in-47041+ #2
[    0.306619] Hardware name: Intel Corporation Skylake Client platform/Skylake Y LPDDR3 RVP3, BIOS SKLSE2R1.R00.B104.B01.1511110114 11/11/2015
[    0.320925] task: ffffffff820134c0 ti: ffffffff82000000 task.ti: ffffffff82000000
[    0.329420] RIP: 0010:[<ffffffff821bca49>]  [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.338821] RSP: 0000:ffffffff82003f18  EFLAGS: 00010246
[    0.344852] RAX: fffffffefce35000 RBX: fffffffefce35000 RCX: fffffffefce2b000
[    0.352952] RDX: 000000008a82b000 RSI: ffffffff8235bb80 RDI: 000000008a835000
[    0.361050] RBP: ffffffff82003f30 R08: 000000008a865000 R09: ffffffffff202850
[    0.369149] R10: ffffffff811ad62f R11: 0000000000000000 R12: 0000000000000000
[    0.377248] R13: ffff88016dbaea40 R14: ffffffff822622c0 R15: ffffffff82003fb0
[    0.385348] FS:  0000000000000000(0000) GS:ffff88016d800000(0000) knlGS:0000000000000000
[    0.394533] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.401054] CR2: fffffffefce35002 CR3: 000000000300c000 CR4: 00000000003406f0
[    0.409153] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    0.417252] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    0.425350] Stack:
[    0.427638]  ffffffffffffffff ffffffff82256900 ffff88016dbaea40 ffffffff82003f40
[    0.436086]  ffffffff821bbce0 ffffffff82003f88 ffffffff8219c0c2 0000000000000000
[    0.444533]  ffffffff8219ba4a ffffffff822622c0 0000000000083000 00000000ffffffff
[    0.452978] Call Trace:
[    0.455763]  [<ffffffff821bbce0>] efi_late_init+0x9/0xb
[    0.461697]  [<ffffffff8219c0c2>] start_kernel+0x463/0x47f
[    0.467928]  [<ffffffff8219ba4a>] ? set_init_arg+0x55/0x55
[    0.474159]  [<ffffffff8219b120>] ? early_idt_handler_array+0x120/0x120
[    0.481669]  [<ffffffff8219b5ee>] x86_64_start_reservations+0x2a/0x2c
[    0.488982]  [<ffffffff8219b72d>] x86_64_start_kernel+0x13d/0x14c
[    0.495897] Code: 00 41 b4 01 48 8b 78 28 e8 09 36 01 00 48 85 c0 48 89 c3 75 13 48 c7 c7 f8 ac d3 81 31 c0 e8 d7 3b fb fe e9 b5 00 00 00 45 84 e4 <44> 8b 6b 02 74 0d be 06 00 00 00 48 89 df e8 ae 34 0$
[    0.518151] RIP  [<ffffffff821bca49>] efi_bgrt_init+0x144/0x1fd
[    0.524888]  RSP <ffffffff82003f18>
[    0.528851] CR2: fffffffefce35002
[    0.532615] ---[ end trace 7b06521e6ebf2aea ]---
[    0.537852] Kernel panic - not syncing: Attempted to kill the idle task!

As said above one way to fix this bug is to shift %cr3 to efi_pgd but we
are not doing that way because it leaks inner details of how we switch
to EFI page tables into a new call site and it also adds duplicate code.
Instead, we remove the call to efi_lookup_mapped_addr() and always
perform early_mem*() instead of early_io*() because we want to remap RAM
regions and not I/O regions. We also delete efi_lookup_mapped_addr()
because we are no longer using it.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Reported-by: Wendy Wang <wendy.wang@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Ricardo Neri <ricardo.neri@intel.com>
Cc: Ravi Shankar <ravi.v.shankar@intel.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2015-12-14 15:24:24 +00:00
Matt Fleming
26d7f65fbd x86/efi: Preface all print statements with efi* tag
The pr_*() calls in the x86 EFI code may or may not include a
subsystem tag, which makes it difficult to grep the kernel log for all
relevant EFI messages and leads users to miss important information.

Recently, a bug reporter provided all the EFI print messages from the
kernel log when trying to diagnose an issue but missed the following
statement because it wasn't prefixed with anything indicating it was
related to EFI,

  pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);

Cc: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2015-12-14 15:24:03 +00:00
Ingo Molnar
d51953b087 x86/platform/uv: Include clocksource.h for clocksource_touch_watchdog()
This build failure triggers on 64-bit allmodconfig:

  arch/x86/platform/uv/uv_nmi.c:493:2: error: implicit declaration of function ‘clocksource_touch_watchdog’ [-Werror=implicit-function-declaration]

which is caused by recent changes exposing a missing clocksource.h include
in uv_nmi.c:

  cc1e24fdb0 x86/vdso: Remove pvclock fixmap machinery

this file got clocksource.h indirectly via fixmap.h - that stealth route
of header inclusion is now gone.

Cc: Borislav Petkov <bp@alien8.de>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-12-11 09:04:04 +01:00
Andy Shevchenko
4077a387b7 x86/platform/iosf_mbi: Remove duplicate definitions
The read and write opcodes are global for all units on SoC and even across
Intel SoCs. Remove duplication of corresponding constants. At the same time
convert all current users.

No functional change.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Boon Leong Ong <boon.leong.ong@intel.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-09 01:18:34 +01:00
Matt Fleming
67a9108ed4 x86/efi: Build our own page table structures
With commit e1a58320a3 ("x86/mm: Warn on W^X mappings") all
users booting on 64-bit UEFI machines see the following warning,

  ------------[ cut here ]------------
  WARNING: CPU: 7 PID: 1 at arch/x86/mm/dump_pagetables.c:225 note_page+0x5dc/0x780()
  x86/mm: Found insecure W+X mapping at address ffff88000005f000/0xffff88000005f000
  ...
  x86/mm: Checked W+X mappings: FAILED, 165660 W+X pages found.
  ...

This is caused by mapping EFI regions with RWX permissions.
There isn't much we can do to restrict the permissions for these
regions due to the way the firmware toolchains mix code and
data, but we can at least isolate these mappings so that they do
not appear in the regular kernel page tables.

In commit d2f7cbe7b2 ("x86/efi: Runtime services virtual
mapping") we started using 'trampoline_pgd' to map the EFI
regions because there was an existing identity mapping there
which we use during the SetVirtualAddressMap() call and for
broken firmware that accesses those addresses.

But 'trampoline_pgd' shares some PGD entries with
'swapper_pg_dir' and does not provide the isolation we require.
Notably the virtual address for __START_KERNEL_map and
MODULES_START are mapped by the same PGD entry so we need to be
more careful when copying changes over in
efi_sync_low_kernel_mappings().

This patch doesn't go the full mile, we still want to share some
PGD entries with 'swapper_pg_dir'. Having completely separate
page tables brings its own issues such as synchronising new
mappings after memory hotplug and module loading. Sharing also
keeps memory usage down.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
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 Jones <davej@codemonkey.org.uk>
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: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1448658575-17029-6-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29 09:15:42 +01:00
Matt Fleming
c9f2a9a65e x86/efi: Hoist page table switching code into efi_call_virt()
This change is a prerequisite for pending patches that switch to
a dedicated EFI page table, instead of using 'trampoline_pgd'
which shares PGD entries with 'swapper_pg_dir'. The pending
patches make it impossible to dereference the runtime service
function pointer without first switching %cr3.

It's true that we now have duplicated switching code in
efi_call_virt() and efi_call_phys_{prolog,epilog}() but we are
sacrificing code duplication for a little more clarity and the
ease of writing the page table switching code in C instead of
asm.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
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 Jones <davej@codemonkey.org.uk>
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: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1448658575-17029-5-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29 09:15:42 +01:00
Matt Fleming
b61a76f885 x86/efi: Map RAM into the identity page table for mixed mode
We are relying on the pre-existing mappings in 'trampoline_pgd'
when accessing function arguments in the EFI mixed mode thunking
code.

Instead let's map memory explicitly so that things will continue
to work when we move to a separate page table in the future.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1448658575-17029-4-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29 09:15:42 +01:00
Matt Fleming
edc3b9129c x86/mm/pat: Ensure cpa->pfn only contains page frame numbers
The x86 pageattr code is confused about the data that is stored
in cpa->pfn, sometimes it's treated as a page frame number,
sometimes it's treated as an unshifted physical address, and in
one place it's treated as a pte.

The result of this is that the mapping functions do not map the
intended physical address.

This isn't a problem in practice because most of the addresses
we're mapping in the EFI code paths are already mapped in
'trampoline_pgd' and so the pageattr mapping functions don't
actually do anything in this case. But when we move to using a
separate page table for the EFI runtime this will be an issue.

Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.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: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1448658575-17029-3-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-29 09:15:42 +01:00
Linus Torvalds
66ef3493d4 Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 platform changes from Ingo Molnar:
 "Misc updates to the Intel MID and SGI UV platforms"

* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel-mid: Make intel_mid_ops static
  arch/x86/intel-mid: Use kmemdup rather than duplicating its implementation
  x86/platform/uv: Implement simple dump failover if kdump fails
  x86/platform/uv: Insert per_cpu accessor function on uv_hub_nmi
2015-11-03 21:33:18 -08:00
Ard Biesheuvel
44511fb9e5 efi: Use correct type for struct efi_memory_map::phys_map
We have been getting away with using a void* for the physical
address of the UEFI memory map, since, even on 32-bit platforms
with 64-bit physical addresses, no truncation takes place if the
memory map has been allocated by the firmware (which only uses
1:1 virtually addressable memory), which is usually the case.

However, commit:

  0f96a99dab ("efi: Add "efi_fake_mem" boot option")

adds code that clones and modifies the UEFI memory map, and the
clone may live above 4 GB on 32-bit platforms.

This means our use of void* for struct efi_memory_map::phys_map has
graduated from 'incorrect but working' to 'incorrect and
broken', and we need to fix it.

So redefine struct efi_memory_map::phys_map as phys_addr_t, and
get rid of a bunch of casts that are now unneeded.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-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: izumi.taku@jp.fujitsu.com
Cc: kamezawa.hiroyu@jp.fujitsu.com
Cc: linux-efi@vger.kernel.org
Cc: matt.fleming@intel.com
Link: http://lkml.kernel.org/r/1445593697-1342-1-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-28 12:28:06 +01:00
Ingo Molnar
790a2ee242 * Make the EFI System Resource Table (ESRT) driver explicitly
non-modular by ripping out the module_* code since Kconfig doesn't
    allow it to be built as a module anyway - Paul Gortmaker
 
  * Make the x86 efi=debug kernel parameter, which enables EFI debug
    code and output, generic and usable by arm64 - Leif Lindholm
 
  * Add support to the x86 EFI boot stub for 64-bit Graphics Output
    Protocol frame buffer addresses - Matt Fleming
 
  * Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled
    in the firmware and set an efi.flags bit so the kernel knows when
    it can apply more strict runtime mapping attributes - Ard Biesheuvel
 
  * Auto-load the efi-pstore module on EFI systems, just like we
    currently do for the efivars module - Ben Hutchings
 
  * Add "efi_fake_mem" kernel parameter which allows the system's EFI
    memory map to be updated with additional attributes for specific
    memory ranges. This is useful for testing the kernel code that handles
    the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware
    doesn't include support - Taku Izumi
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Merge tag 'efi-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into core/efi

Pull v4.4 EFI updates from Matt Fleming:

  - Make the EFI System Resource Table (ESRT) driver explicitly
    non-modular by ripping out the module_* code since Kconfig doesn't
    allow it to be built as a module anyway. (Paul Gortmaker)

  - Make the x86 efi=debug kernel parameter, which enables EFI debug
    code and output, generic and usable by arm64. (Leif Lindholm)

  - Add support to the x86 EFI boot stub for 64-bit Graphics Output
    Protocol frame buffer addresses. (Matt Fleming)

  - Detect when the UEFI v2.5 EFI_PROPERTIES_TABLE feature is enabled
    in the firmware and set an efi.flags bit so the kernel knows when
    it can apply more strict runtime mapping attributes - Ard Biesheuvel

  - Auto-load the efi-pstore module on EFI systems, just like we
    currently do for the efivars module. (Ben Hutchings)

  - Add "efi_fake_mem" kernel parameter which allows the system's EFI
    memory map to be updated with additional attributes for specific
    memory ranges. This is useful for testing the kernel code that handles
    the EFI_MEMORY_MORE_RELIABLE memmap bit even if your firmware
    doesn't include support. (Taku Izumi)

Note: there is a semantic conflict between the following two commits:

  8a53554e12 ("x86/efi: Fix multiple GOP device support")
  ae2ee627dc ("efifb: Add support for 64-bit frame buffer addresses")

I fixed up the interaction in the merge commit, changing the type of
current_fb_base from u32 to u64.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14 16:51:34 +02:00
Ingo Molnar
c7d77a7980 Merge branch 'x86/urgent' into core/efi, to pick up a pending EFI fix
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-14 16:05:18 +02:00
Taku Izumi
0bbea1ce98 x86/efi: Rename print_efi_memmap() to efi_print_memmap()
This patch renames print_efi_memmap() to efi_print_memmap() and
make it global function so that we can invoke it outside of
arch/x86/platform/efi/efi.c

Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12 14:20:08 +01:00
Leif Lindholm
12dd00e83f efi/x86: Move efi=debug option parsing to core
fed6cefe3b ("x86/efi: Add a "debug" option to the efi= cmdline")
adds the DBG flag, but does so for x86 only. Move this early param
parsing to core code.

Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2015-10-12 14:20:05 +01:00
Andy Shevchenko
d1f0f6c72c x86/intel-mid: Make intel_mid_ops static
The following warning is issued on unfixed code.

arch/x86/platform/intel-mid/intel-mid.c:64:22: warning: symbol 'intel_mid_ops' was not declared. Should it be static?

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: http://lkml.kernel.org/r/1444400741-98669-1-git-send-email-andriy.shevchenko@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-10-11 21:03:12 +02:00
Matt Fleming
a5caa209ba x86/efi: Fix boot crash by mapping EFI memmap entries bottom-up at runtime, instead of top-down
Beginning with UEFI v2.5 EFI_PROPERTIES_TABLE was introduced
that signals that the firmware PE/COFF loader supports splitting
code and data sections of PE/COFF images into separate EFI
memory map entries. This allows the kernel to map those regions
with strict memory protections, e.g. EFI_MEMORY_RO for code,
EFI_MEMORY_XP for data, etc.

Unfortunately, an unwritten requirement of this new feature is
that the regions need to be mapped with the same offsets
relative to each other as observed in the EFI memory map. If
this is not done crashes like this may occur,

  BUG: unable to handle kernel paging request at fffffffefe6086dd
  IP: [<fffffffefe6086dd>] 0xfffffffefe6086dd
  Call Trace:
   [<ffffffff8104c90e>] efi_call+0x7e/0x100
   [<ffffffff81602091>] ? virt_efi_set_variable+0x61/0x90
   [<ffffffff8104c583>] efi_delete_dummy_variable+0x63/0x70
   [<ffffffff81f4e4aa>] efi_enter_virtual_mode+0x383/0x392
   [<ffffffff81f37e1b>] start_kernel+0x38a/0x417
   [<ffffffff81f37495>] x86_64_start_reservations+0x2a/0x2c
   [<ffffffff81f37582>] x86_64_start_kernel+0xeb/0xef

Here 0xfffffffefe6086dd refers to an address the firmware
expects to be mapped but which the OS never claimed was mapped.
The issue is that included in these regions are relative
addresses to other regions which were emitted by the firmware
toolchain before the "splitting" of sections occurred at
runtime.

Needless to say, we don't satisfy this unwritten requirement on
x86_64 and instead map the EFI memory map entries in reverse
order. The above crash is almost certainly triggerable with any
kernel newer than v3.13 because that's when we rewrote the EFI
runtime region mapping code, in commit d2f7cbe7b2 ("x86/efi:
Runtime services virtual mapping"). For kernel versions before
v3.13 things may work by pure luck depending on the
fragmentation of the kernel virtual address space at the time we
map the EFI regions.

Instead of mapping the EFI memory map entries in reverse order,
where entry N has a higher virtual address than entry N+1, map
them in the same order as they appear in the EFI memory map to
preserve this relative offset between regions.

This patch has been kept as small as possible with the intention
that it should be applied aggressively to stable and
distribution kernels. It is very much a bugfix rather than
support for a new feature, since when EFI_PROPERTIES_TABLE is
enabled we must map things as outlined above to even boot - we
have no way of asking the firmware not to split the code/data
regions.

In fact, this patch doesn't even make use of the more strict
memory protections available in UEFI v2.5. That will come later.

Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chun-Yi <jlee@suse.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: James Bottomley <JBottomley@Odin.com>
Cc: Lee, Chun-Yi <jlee@suse.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-2-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-10-01 12:51:28 +02:00