<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/x86/kernel/cpu/common.c, branch v3.7</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>Merge branch 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2012-10-01T20:59:17+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-10-01T20:59:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=15385dfe7e0fa6866b204dd0d14aec2cc48fc0a7'/>
<id>15385dfe7e0fa6866b204dd0d14aec2cc48fc0a7</id>
<content type='text'>
Pull x86/smap support from Ingo Molnar:
 "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU
  feature on Intel CPUs: a hardware feature that prevents unintended
  user-space data access from kernel privileged code.

  It's turned on automatically when possible.

  This, in combination with SMEP, makes it even harder to exploit kernel
  bugs such as NULL pointer dereferences."

Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added
includes right next to each other.

* 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, smep, smap: Make the switching functions one-way
  x86, suspend: On wakeup always initialize cr4 and EFER
  x86-32: Start out eflags and cr4 clean
  x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
  x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry
  x86, smap: Reduce the SMAP overhead for signal handling
  x86, smap: A page fault due to SMAP is an oops
  x86, smap: Turn on Supervisor Mode Access Prevention
  x86, smap: Add STAC and CLAC instructions to control user space access
  x86, uaccess: Merge prototypes for clear_user/__clear_user
  x86, smap: Add a header file with macros for STAC/CLAC
  x86, alternative: Add header guards to &lt;asm/alternative-asm.h&gt;
  x86, alternative: Use .pushsection/.popsection
  x86, smap: Add CR4 bit for SMAP
  x86-32, mm: The WP test should be done on a kernel page
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86/smap support from Ingo Molnar:
 "This adds support for the SMAP (Supervisor Mode Access Prevention) CPU
  feature on Intel CPUs: a hardware feature that prevents unintended
  user-space data access from kernel privileged code.

  It's turned on automatically when possible.

  This, in combination with SMEP, makes it even harder to exploit kernel
  bugs such as NULL pointer dereferences."

Fix up trivial conflict in arch/x86/kernel/entry_64.S due to newly added
includes right next to each other.

* 'x86-smap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, smep, smap: Make the switching functions one-way
  x86, suspend: On wakeup always initialize cr4 and EFER
  x86-32: Start out eflags and cr4 clean
  x86, smap: Do not abuse the [f][x]rstor_checking() functions for user space
  x86-32, smap: Add STAC/CLAC instructions to 32-bit kernel entry
  x86, smap: Reduce the SMAP overhead for signal handling
  x86, smap: A page fault due to SMAP is an oops
  x86, smap: Turn on Supervisor Mode Access Prevention
  x86, smap: Add STAC and CLAC instructions to control user space access
  x86, uaccess: Merge prototypes for clear_user/__clear_user
  x86, smap: Add a header file with macros for STAC/CLAC
  x86, alternative: Add header guards to &lt;asm/alternative-asm.h&gt;
  x86, alternative: Use .pushsection/.popsection
  x86, smap: Add CR4 bit for SMAP
  x86-32, mm: The WP test should be done on a kernel page
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2012-10-01T18:13:33+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-10-01T18:13:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=229993001282e128a49a59ec43d255614775703a'/>
<id>229993001282e128a49a59ec43d255614775703a</id>
<content type='text'>
Pull x86/mm changes from Ingo Molnar:
 "The biggest change is new TLB partial flushing code for AMD CPUs.
  (The v3.6 kernel had the Intel CPU side code, see commits
  e0ba94f14f74..effee4b9b3b.)

  There's also various other refinements around the TLB flush code"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Distinguish TLB shootdown interrupts from other functions call interrupts
  x86/mm: Fix range check in tlbflush debugfs interface
  x86, cpu: Preset default tlb_flushall_shift on AMD
  x86, cpu: Add AMD TLB size detection
  x86, cpu: Push TLB detection CPUID check down
  x86, cpu: Fixup tlb_flushall_shift formatting
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86/mm changes from Ingo Molnar:
 "The biggest change is new TLB partial flushing code for AMD CPUs.
  (The v3.6 kernel had the Intel CPU side code, see commits
  e0ba94f14f74..effee4b9b3b.)

  There's also various other refinements around the TLB flush code"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Distinguish TLB shootdown interrupts from other functions call interrupts
  x86/mm: Fix range check in tlbflush debugfs interface
  x86, cpu: Preset default tlb_flushall_shift on AMD
  x86, cpu: Add AMD TLB size detection
  x86, cpu: Push TLB detection CPUID check down
  x86, cpu: Fixup tlb_flushall_shift formatting
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2012-10-01T18:10:52+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-10-01T18:10:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ac07f5c3cb0cf19258c55cdf210aa4ac91ca7330'/>
<id>ac07f5c3cb0cf19258c55cdf210aa4ac91ca7330</id>
<content type='text'>
Pull x86/fpu update from Ingo Molnar:
 "The biggest change is the addition of the non-lazy (eager) FPU saving
  support model and enabling it on CPUs with optimized xsaveopt/xrstor
  FPU state saving instructions.

  There are also various Sparse fixes"

Fix up trivial add-add conflict in arch/x86/kernel/traps.c

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, kvm: fix kvm's usage of kernel_fpu_begin/end()
  x86, fpu: remove cpu_has_xmm check in the fx_finit()
  x86, fpu: make eagerfpu= boot param tri-state
  x86, fpu: enable eagerfpu by default for xsaveopt
  x86, fpu: decouple non-lazy/eager fpu restore from xsave
  x86, fpu: use non-lazy fpu restore for processors supporting xsave
  lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models
  x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage
  x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu()
  x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig()
  x86, fpu: drop_fpu() before restoring new state from sigframe
  x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels
  x86, fpu: Consolidate inline asm routines for saving/restoring fpu state
  x86, signal: Cleanup ifdefs and is_ia32, is_x32
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86/fpu update from Ingo Molnar:
 "The biggest change is the addition of the non-lazy (eager) FPU saving
  support model and enabling it on CPUs with optimized xsaveopt/xrstor
  FPU state saving instructions.

  There are also various Sparse fixes"

Fix up trivial add-add conflict in arch/x86/kernel/traps.c

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, kvm: fix kvm's usage of kernel_fpu_begin/end()
  x86, fpu: remove cpu_has_xmm check in the fx_finit()
  x86, fpu: make eagerfpu= boot param tri-state
  x86, fpu: enable eagerfpu by default for xsaveopt
  x86, fpu: decouple non-lazy/eager fpu restore from xsave
  x86, fpu: use non-lazy fpu restore for processors supporting xsave
  lguest, x86: handle guest TS bit for lazy/non-lazy fpu host models
  x86, fpu: always use kernel_fpu_begin/end() for in-kernel FPU usage
  x86, kvm: use kernel_fpu_begin/end() in kvm_load/put_guest_fpu()
  x86, fpu: remove unnecessary user_fpu_end() in save_xstate_sig()
  x86, fpu: drop_fpu() before restoring new state from sigframe
  x86, fpu: Unify signal handling code paths for x86 and x86_64 kernels
  x86, fpu: Consolidate inline asm routines for saving/restoring fpu state
  x86, signal: Cleanup ifdefs and is_ia32, is_x32
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2012-10-01T18:07:31+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2012-10-01T18:07:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=58ae9c0d54ae3916614fa1f3756dadb954f16e6c'/>
<id>58ae9c0d54ae3916614fa1f3756dadb954f16e6c</id>
<content type='text'>
Pull x86 debug update from Ingo Molnar:
 "Various small enhancements"

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/debug: Dump family, model, stepping of the boot CPU
  x86/iommu: Use NULL instead of plain 0 for __IOMMU_INIT
  x86/iommu: Drop duplicate const in __IOMMU_INIT
  x86/fpu/xsave: Keep __user annotation in casts
  x86/pci/probe_roms: Add missing __iomem annotation to pci_map_biosrom()
  x86/signals: ia32_signal.c: add __user casts to fix sparse warnings
  x86/vdso: Add __user annotation to VDSO32_SYMBOL
  x86: Fix __user annotations in asm/sys_ia32.h
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 debug update from Ingo Molnar:
 "Various small enhancements"

* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/debug: Dump family, model, stepping of the boot CPU
  x86/iommu: Use NULL instead of plain 0 for __IOMMU_INIT
  x86/iommu: Drop duplicate const in __IOMMU_INIT
  x86/fpu/xsave: Keep __user annotation in casts
  x86/pci/probe_roms: Add missing __iomem annotation to pci_map_biosrom()
  x86/signals: ia32_signal.c: add __user casts to fix sparse warnings
  x86/vdso: Add __user annotation to VDSO32_SYMBOL
  x86: Fix __user annotations in asm/sys_ia32.h
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, smep, smap: Make the switching functions one-way</title>
<updated>2012-09-27T16:52:38+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2012-09-27T01:02:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b2cc2a074de75671bbed5e2dda67a9252ef353ea'/>
<id>b2cc2a074de75671bbed5e2dda67a9252ef353ea</id>
<content type='text'>
There is no fundamental reason why we should switch SMEP and SMAP on
during early cpu initialization just to switch them off again.  Now
with %eflags and %cr4 forced to be initialized to a clean state, we
only need the one-way enable.  Also, make the functions inline to make
them (somewhat) harder to abuse.

This does mean that SMEP and SMAP do not get initialized anywhere near
as early.  Even using early_param() instead of __setup() doesn't give
us control early enough to do this during the early cpu initialization
phase.  This seems reasonable to me, because SMEP and SMAP should not
matter until we have userspace to protect ourselves from, but it does
potentially make it possible for a bug involving a "leak of
permissions to userspace" to get uncaught.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
There is no fundamental reason why we should switch SMEP and SMAP on
during early cpu initialization just to switch them off again.  Now
with %eflags and %cr4 forced to be initialized to a clean state, we
only need the one-way enable.  Also, make the functions inline to make
them (somewhat) harder to abuse.

This does mean that SMEP and SMAP do not get initialized anywhere near
as early.  Even using early_param() instead of __setup() doesn't give
us control early enough to do this during the early cpu initialization
phase.  This seems reasonable to me, because SMEP and SMAP should not
matter until we have userspace to protect ourselves from, but it does
potentially make it possible for a bug involving a "leak of
permissions to userspace" to get uncaught.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86/fpu' into x86/smap</title>
<updated>2012-09-22T00:18:44+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2012-09-22T00:18:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=49b8c695e331c9685e6ffdbf34872509d77c8459'/>
<id>49b8c695e331c9685e6ffdbf34872509d77c8459</id>
<content type='text'>
Reason for merge:
       x86/fpu changed the structure of some of the code that x86/smap
       changes; mostly fpu-internal.h but also minor changes to the
       signal code.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;

Resolved Conflicts:
	arch/x86/ia32/ia32_signal.c
	arch/x86/include/asm/fpu-internal.h
	arch/x86/kernel/signal.c
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Reason for merge:
       x86/fpu changed the structure of some of the code that x86/smap
       changes; mostly fpu-internal.h but also minor changes to the
       signal code.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;

Resolved Conflicts:
	arch/x86/ia32/ia32_signal.c
	arch/x86/include/asm/fpu-internal.h
	arch/x86/kernel/signal.c
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, smap: Turn on Supervisor Mode Access Prevention</title>
<updated>2012-09-21T19:45:27+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2012-09-21T19:43:13+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=52b6179ac87d33c2eeaff5292786a10fe98cff64'/>
<id>52b6179ac87d33c2eeaff5292786a10fe98cff64</id>
<content type='text'>
If Supervisor Mode Access Prevention is available and not disabled by
the user, turn it on.  Also fix the expansion of SMEP (Supervisor Mode
Execution Prevention.)

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/1348256595-29119-10-git-send-email-hpa@linux.intel.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
If Supervisor Mode Access Prevention is available and not disabled by
the user, turn it on.  Also fix the expansion of SMEP (Supervisor Mode
Execution Prevention.)

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/1348256595-29119-10-git-send-email-hpa@linux.intel.com
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, smap: Add STAC and CLAC instructions to control user space access</title>
<updated>2012-09-21T19:45:27+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2012-09-21T19:43:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=63bcff2a307b9bcc712a8251eb27df8b2e117967'/>
<id>63bcff2a307b9bcc712a8251eb27df8b2e117967</id>
<content type='text'>
When Supervisor Mode Access Prevention (SMAP) is enabled, access to
userspace from the kernel is controlled by the AC flag.  To make the
performance of manipulating that flag acceptable, there are two new
instructions, STAC and CLAC, to set and clear it.

This patch adds those instructions, via alternative(), when the SMAP
feature is enabled.  It also adds X86_EFLAGS_AC unconditionally to the
SYSCALL entry mask; there is simply no reason to make that one
conditional.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When Supervisor Mode Access Prevention (SMAP) is enabled, access to
userspace from the kernel is controlled by the AC flag.  To make the
performance of manipulating that flag acceptable, there are two new
instructions, STAC and CLAC, to set and clear it.

This patch adds those instructions, via alternative(), when the SMAP
feature is enabled.  It also adds X86_EFLAGS_AC unconditionally to the
SYSCALL entry mask; there is simply no reason to make that one
conditional.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/1348256595-29119-9-git-send-email-hpa@linux.intel.com
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/debug: Dump family, model, stepping of the boot CPU</title>
<updated>2012-09-19T15:12:01+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>borislav.petkov@amd.com</email>
</author>
<published>2012-09-14T16:37:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=924e101a7ab6f884047f4344e5f1154a4bcd63a6'/>
<id>924e101a7ab6f884047f4344e5f1154a4bcd63a6</id>
<content type='text'>
When acting on a user bug report, we find ourselves constantly
asking for /proc/cpuinfo in order to know the exact family,
model, stepping of the CPU in question.

Instead of having to ask this, add this to dmesg so that it is
visible and no ambiguities can ensue from looking at the
official name string of the CPU coming from CPUID and trying
to map it to f/m/s.

Output then looks like this:

[    0.146041] smpboot: CPU0: AMD FX(tm)-8100 Eight-Core Processor (fam: 15, model: 01, stepping: 02)

Signed-off-by: Borislav Petkov &lt;borislav.petkov@amd.com&gt;
Cc: Andreas Herrmann &lt;andreas.herrmann3@amd.com&gt;
Link: http://lkml.kernel.org/r/1347640666-13638-1-git-send-email-bp@amd64.org
[ tweaked it minimally to add commas. ]
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
When acting on a user bug report, we find ourselves constantly
asking for /proc/cpuinfo in order to know the exact family,
model, stepping of the CPU in question.

Instead of having to ask this, add this to dmesg so that it is
visible and no ambiguities can ensue from looking at the
official name string of the CPU coming from CPUID and trying
to map it to f/m/s.

Output then looks like this:

[    0.146041] smpboot: CPU0: AMD FX(tm)-8100 Eight-Core Processor (fam: 15, model: 01, stepping: 02)

Signed-off-by: Borislav Petkov &lt;borislav.petkov@amd.com&gt;
Cc: Andreas Herrmann &lt;andreas.herrmann3@amd.com&gt;
Link: http://lkml.kernel.org/r/1347640666-13638-1-git-send-email-bp@amd64.org
[ tweaked it minimally to add commas. ]
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, fpu: decouple non-lazy/eager fpu restore from xsave</title>
<updated>2012-09-18T22:52:22+00:00</updated>
<author>
<name>Suresh Siddha</name>
<email>suresh.b.siddha@intel.com</email>
</author>
<published>2012-09-06T21:58:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5d2bd7009f306c82afddd1ca4d9763ad8473c216'/>
<id>5d2bd7009f306c82afddd1ca4d9763ad8473c216</id>
<content type='text'>
Decouple non-lazy/eager fpu restore policy from the existence of the xsave
feature. Introduce a synthetic CPUID flag to represent the eagerfpu
policy. "eagerfpu=on" boot paramter will enable the policy.

Requested-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
Requested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Suresh Siddha &lt;suresh.b.siddha@intel.com&gt;
Link: http://lkml.kernel.org/r/1347300665-6209-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Decouple non-lazy/eager fpu restore policy from the existence of the xsave
feature. Introduce a synthetic CPUID flag to represent the eagerfpu
policy. "eagerfpu=on" boot paramter will enable the policy.

Requested-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
Requested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Suresh Siddha &lt;suresh.b.siddha@intel.com&gt;
Link: http://lkml.kernel.org/r/1347300665-6209-2-git-send-email-suresh.b.siddha@intel.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
