linux-stable.git/arch/x86/kernel/cpu/amd.c, branch linux-3.13.y Linux kernel stable tree x86, cpu, amd: Add workaround for family 16h, erratum 793 2014-02-06T19:34:12+00:00 Borislav Petkov bp@suse.de 2014-01-14T23:07:11+00:00 31752e89b1e728d672eaafaa7869e7c0673ae9f6 commit 3b56496865f9f7d9bcb2f93b44c63f274f08e3b6 upstream. This adds the workaround for erratum 793 as a precaution in case not every BIOS implements it. This addresses CVE-2013-6885. Erratum text: [Revision Guide for AMD Family 16h Models 00h-0Fh Processors, document 51810 Rev. 3.04 November 2013] 793 Specific Combination of Writes to Write Combined Memory Types and Locked Instructions May Cause Core Hang Description Under a highly specific and detailed set of internal timing conditions, a locked instruction may trigger a timing sequence whereby the write to a write combined memory type is not flushed, causing the locked instruction to stall indefinitely. Potential Effect on System Processor core hang. Suggested Workaround BIOS should set MSR C001_1020[15] = 1b. Fix Planned No fix planned [ hpa: updated description, fixed typo in MSR name ] Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/20140114230711.GS29865@pd.tnic Tested-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3b56496865f9f7d9bcb2f93b44c63f274f08e3b6 upstream.

This adds the workaround for erratum 793 as a precaution in case not
every BIOS implements it.  This addresses CVE-2013-6885.

Erratum text:

[Revision Guide for AMD Family 16h Models 00h-0Fh Processors,
document 51810 Rev. 3.04 November 2013]

793 Specific Combination of Writes to Write Combined Memory Types and
Locked Instructions May Cause Core Hang

Description

Under a highly specific and detailed set of internal timing
conditions, a locked instruction may trigger a timing sequence whereby
the write to a write combined memory type is not flushed, causing the
locked instruction to stall indefinitely.

Potential Effect on System

Processor core hang.

Suggested Workaround

BIOS should set MSR
C001_1020[15] = 1b.

Fix Planned

No fix planned

[ hpa: updated description, fixed typo in MSR name ]

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20140114230711.GS29865@pd.tnic
Tested-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-16T00:47:22+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-11-16T00:47:22+00:00 9073e1a804c3096eda84ee7cbf11d1f174236c75 Pull trivial tree updates from Jiri Kosina: "Usual earth-shaking, news-breaking, rocket science pile from trivial.git" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits) doc: usb: Fix typo in Documentation/usb/gadget_configs.txt doc: add missing files to timers/00-INDEX timekeeping: Fix some trivial typos in comments mm: Fix some trivial typos in comments irq: Fix some trivial typos in comments NUMA: fix typos in Kconfig help text mm: update 00-INDEX doc: Documentation/DMA-attributes.txt fix typo DRM: comment: `halve' -> `half' Docs: Kconfig: `devlopers' -> `developers' doc: typo on word accounting in kprobes.c in mutliple architectures treewide: fix "usefull" typo treewide: fix "distingush" typo mm/Kconfig: Grammar s/an/a/ kexec: Typo s/the/then/ Documentation/kvm: Update cpuid documentation for steal time and pv eoi treewide: Fix common typo in "identify" __page_to_pfn: Fix typo in comment Correct some typos for word frequency clk: fixed-factor: Fix a trivial typo ... 
Pull trivial tree updates from Jiri Kosina:
 "Usual earth-shaking, news-breaking, rocket science pile from
  trivial.git"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  doc: usb: Fix typo in Documentation/usb/gadget_configs.txt
  doc: add missing files to timers/00-INDEX
  timekeeping: Fix some trivial typos in comments
  mm: Fix some trivial typos in comments
  irq: Fix some trivial typos in comments
  NUMA: fix typos in Kconfig help text
  mm: update 00-INDEX
  doc: Documentation/DMA-attributes.txt fix typo
  DRM: comment: `halve' -> `half'
  Docs: Kconfig: `devlopers' -> `developers'
  doc: typo on word accounting in kprobes.c in mutliple architectures
  treewide: fix "usefull" typo
  treewide: fix "distingush" typo
  mm/Kconfig: Grammar s/an/a/
  kexec: Typo s/the/then/
  Documentation/kvm: Update cpuid documentation for steal time and pv eoi
  treewide: Fix common typo in "identify"
  __page_to_pfn: Fix typo in comment
  Correct some typos for word frequency
  clk: fixed-factor: Fix a trivial typo
  ...
x86/cpu: Track legacy CPU model data only on 32-bit kernels 2013-10-26T11:34:39+00:00 Jan Beulich JBeulich@suse.com 2013-10-21T08:35:20+00:00 09dc68d958c67c76cf672ec78b7391af453010f8 struct cpu_dev's c_models is only ever set inside CONFIG_X86_32 conditionals (or code that's being built for 32-bit only), so there's no use of reserving the (empty) space for the model names in a 64-bit kernel. Similarly, c_size_cache is only used in the #else of a CONFIG_X86_64 conditional, so reserving space for (and in one case even initializing) that field is pointless for 64-bit kernels too. While moving both fields to the end of the structure, I also noticed that: - the c_models array size was one too small, potentially causing table_lookup_model() to return garbage on Intel CPUs (intel.c's instance was lacking the sentinel with family being zero), so the patch bumps that by one, - c_models' vendor sub-field was unused (and anyway redundant with the base structure's c_x86_vendor field), so the patch deletes it. Also rename the legacy fields so that their legacy nature stands out and comment their declarations. Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
struct cpu_dev's c_models is only ever set inside CONFIG_X86_32
conditionals (or code that's being built for 32-bit only), so
there's no use of reserving the (empty) space for the model
names in a 64-bit kernel.

Similarly, c_size_cache is only used in the #else of a
CONFIG_X86_64 conditional, so reserving space for (and in one
case even initializing) that field is pointless for 64-bit
kernels too.

While moving both fields to the end of the structure, I also
noticed that:

 - the c_models array size was one too small, potentially causing
   table_lookup_model() to return garbage on Intel CPUs (intel.c's
   instance was lacking the sentinel with family being zero), so the
   patch bumps that by one,

 - c_models' vendor sub-field was unused (and anyway redundant
   with the base structure's c_x86_vendor field), so the patch deletes it.

Also rename the legacy fields so that their legacy nature stands out
and comment their declarations.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Link: http://lkml.kernel.org/r/5265036802000078000FC4DB@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
treewide: fix "distingush" typo 2013-10-14T13:38:33+00:00 Michael Opdenacker michael.opdenacker@free-electrons.com 2013-09-18T04:00:43+00:00 aa5e5dc2a8878ecf1a94819d889939023fd576c9 Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> 
Signed-off-by: Michael Opdenacker <michael.opdenacker@free-electrons.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Merge branch 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2013-09-04T15:42:44+00:00 Linus Torvalds torvalds@linux-foundation.org 2013-09-04T15:42:44+00:00 2a475501b81f06f64c474cfad66f8807294b4534 Pull x86/asmlinkage changes from Ingo Molnar: "As a preparation for Andi Kleen's LTO patchset (link time optimizations using GCC's -flto which build time optimization has steadily increased in quality over the past few years and might eventually be usable for the kernel too) this tree includes a handful of preparatory patches that make function calling convention annotations consistent again: - Mark every function without arguments (or 64bit only) that is used by assembly code with asmlinkage() - Mark every function with parameters or variables that is used by assembly code as __visible. For the vanilla kernel this has documentation, consistency and debuggability advantages, for the time being" * 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/asmlinkage: Fix warning in xen asmlinkage change x86, asmlinkage, vdso: Mark vdso variables __visible x86, asmlinkage, power: Make various symbols used by the suspend asm code visible x86, asmlinkage: Make dump_stack visible x86, asmlinkage: Make 64bit checksum functions visible x86, asmlinkage, paravirt: Add __visible/asmlinkage to xen paravirt ops x86, asmlinkage, apm: Make APM data structure used from assembler visible x86, asmlinkage: Make syscall tables visible x86, asmlinkage: Make several variables used from assembler/linker script visible x86, asmlinkage: Make kprobes code visible and fix assembler code x86, asmlinkage: Make various syscalls asmlinkage x86, asmlinkage: Make 32bit/64bit __switch_to visible x86, asmlinkage: Make _*_start_kernel visible x86, asmlinkage: Make all interrupt handlers asmlinkage / __visible x86, asmlinkage: Change dotraplinkage into __visible on 32bit x86: Fix sys_call_table type in asm/syscall.h 
Pull x86/asmlinkage changes from Ingo Molnar:
 "As a preparation for Andi Kleen's LTO patchset (link time
  optimizations using GCC's -flto which build time optimization has
  steadily increased in quality over the past few years and might
  eventually be usable for the kernel too) this tree includes a handful
  of preparatory patches that make function calling convention
  annotations consistent again:

   - Mark every function without arguments (or 64bit only) that is used
     by assembly code with asmlinkage()

   - Mark every function with parameters or variables that is used by
     assembly code as __visible.

  For the vanilla kernel this has documentation, consistency and
  debuggability advantages, for the time being"

* 'x86-asmlinkage-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/asmlinkage: Fix warning in xen asmlinkage change
  x86, asmlinkage, vdso: Mark vdso variables __visible
  x86, asmlinkage, power: Make various symbols used by the suspend asm code visible
  x86, asmlinkage: Make dump_stack visible
  x86, asmlinkage: Make 64bit checksum functions visible
  x86, asmlinkage, paravirt: Add __visible/asmlinkage to xen paravirt ops
  x86, asmlinkage, apm: Make APM data structure used from assembler visible
  x86, asmlinkage: Make syscall tables visible
  x86, asmlinkage: Make several variables used from assembler/linker script visible
  x86, asmlinkage: Make kprobes code visible and fix assembler code
  x86, asmlinkage: Make various syscalls asmlinkage
  x86, asmlinkage: Make 32bit/64bit __switch_to visible
  x86, asmlinkage: Make _*_start_kernel visible
  x86, asmlinkage: Make all interrupt handlers asmlinkage / __visible
  x86, asmlinkage: Change dotraplinkage into __visible on 32bit
  x86: Fix sys_call_table type in asm/syscall.h
x86, microcode, AMD: Make cpu_has_amd_erratum() use the correct struct cpuinfo_x86 2013-08-12T16:25:00+00:00 Torsten Kaiser just.for.lkml@googlemail.com 2013-07-23T17:40:49+00:00 8c6b79bb1211d91fb31bcbc2a1eea8d6963d3ad9 cpu_has_amd_erratum() is buggy, because it uses the per-cpu cpu_info before it is filled by smp_store_boot_cpu_info() / smp_store_cpu_info(). If early microcode loading is enabled its collect_cpu_info_amd_early() will fill ->x86 and so the fallback to boot_cpu_data is not used. But ->x86_vendor was not filled and is still X86_VENDOR_INTEL resulting in no errata fixes getting applied and my system hangs on boot. Using cpu_info in cpu_has_amd_erratum() is wrong anyway: its only caller init_amd() will have a struct cpuinfo_x86 as parameter and the set_cpu_bug() that is controlled by cpu_has_amd_erratum() also only uses that struct. So pass the struct cpuinfo_x86 from init_amd() to cpu_has_amd_erratum() and the broken fallback can be dropped. [ Boris: Drop WARN_ON() since we're called only from init_amd() ] Signed-off-by: Torsten Kaiser <just.for.lkml@googlemail.com> Signed-off-by: Borislav Petkov <bp@suse.de> 
cpu_has_amd_erratum() is buggy, because it uses the per-cpu cpu_info
before it is filled by smp_store_boot_cpu_info() / smp_store_cpu_info().

If early microcode loading is enabled its collect_cpu_info_amd_early()
will fill ->x86 and so the fallback to boot_cpu_data is not used. But
->x86_vendor was not filled and is still X86_VENDOR_INTEL resulting in
no errata fixes getting applied and my system hangs on boot.

Using cpu_info in cpu_has_amd_erratum() is wrong anyway: its only
caller init_amd() will have a struct cpuinfo_x86 as parameter and the
set_cpu_bug() that is controlled by cpu_has_amd_erratum() also only uses
that struct.

So pass the struct cpuinfo_x86 from init_amd() to cpu_has_amd_erratum()
and the broken fallback can be dropped.

[ Boris: Drop WARN_ON() since we're called only from init_amd() ]

Signed-off-by: Torsten Kaiser <just.for.lkml@googlemail.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
x86, asmlinkage: Make several variables used from assembler/linker script visible 2013-08-06T21:20:13+00:00 Andi Kleen ak@linux.intel.com 2013-08-05T22:02:43+00:00 277d5b40b7bf495d2d4193746181b17dd98441b2 Plus one function, load_gs_index(). Signed-off-by: Andi Kleen <ak@linux.intel.com> Link: http://lkml.kernel.org/r/1375740170-7446-10-git-send-email-andi@firstfloor.org Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> 
Plus one function, load_gs_index().

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/1375740170-7446-10-git-send-email-andi@firstfloor.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
x86: delete __cpuinit usage from all x86 files 2013-07-14T23:36:56+00:00 Paul Gortmaker paul.gortmaker@windriver.com 2013-06-18T22:23:59+00:00 148f9bb87745ed45f7a11b2cbd3bc0f017d5d257 The __cpuinit type of throwaway sections might have made sense some time ago when RAM was more constrained, but now the savings do not offset the cost and complications. For example, the fix in commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time") is a good example of the nasty type of bugs that can be created with improper use of the various __init prefixes. After a discussion on LKML[1] it was decided that cpuinit should go the way of devinit and be phased out. Once all the users are gone, we can then finally remove the macros themselves from linux/init.h. Note that some harmless section mismatch warnings may result, since notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c) are flagged as __cpuinit -- so if we remove the __cpuinit from arch specific callers, we will also get section mismatch warnings. As an intermediate step, we intend to turn the linux/init.h cpuinit content into no-ops as early as possible, since that will get rid of these warnings. In any case, they are temporary and harmless. This removes all the arch/x86 uses of the __cpuinit macros from all C files. x86 only had the one __CPUINIT used in assembly files, and it wasn't paired off with a .previous or a __FINIT, so we can delete it directly w/o any corresponding additional change there. [1] https://lkml.org/lkml/2013/5/20/589 Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: x86@kernel.org Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> 
The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

Note that some harmless section mismatch warnings may result, since
notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
are flagged as __cpuinit  -- so if we remove the __cpuinit from
arch specific callers, we will also get section mismatch warnings.
As an intermediate step, we intend to turn the linux/init.h cpuinit
content into no-ops as early as possible, since that will get rid
of these warnings.  In any case, they are temporary and harmless.

This removes all the arch/x86 uses of the __cpuinit macros from
all C files.  x86 only had the one __CPUINIT used in assembly files,
and it wasn't paired off with a .previous or a __FINIT, so we can
delete it directly w/o any corresponding additional change there.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
mm/x86: prepare for removing num_physpages and simplify mem_init() 2013-07-03T23:07:38+00:00 Jiang Liu liuj97@gmail.com 2013-07-03T22:04:19+00:00 46a841329a6cd6298e131afd82e7d58130b19025 Prepare for removing num_physpages and simplify mem_init(). Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Andreas Herrmann <andreas.herrmann3@amd.com> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Wen Congyang <wency@cn.fujitsu.com> Cc: Jianguo Wu <wujianguo@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Prepare for removing num_physpages and simplify mem_init().

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
x86, CPU, AMD: Drop useless label 2013-04-16T09:50:51+00:00 Borislav Petkov bp@suse.de 2013-04-08T15:57:46+00:00 1077c932db63ecc571c31df1c24d4a44e30928e5 All we want to do is return from this function so stop jumping around like a flea for no good reason. Signed-off-by: Borislav Petkov <bp@suse.de> Link: http://lkml.kernel.org/r/1365436666-9837-5-git-send-email-bp@alien8.de Signed-off-by: H. Peter Anvin <hpa@zytor.com> 
All we want to do is return from this function so stop jumping around
like a flea for no good reason.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/1365436666-9837-5-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin <hpa@zytor.com>