<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/x86/kernel/cpu/intel.c, branch v3.17</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<entry>
<title>Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-08-05T00:15:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-08-05T00:15:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=ce4747963252a30613ebf1c1df3d83b9526a342e'/>
<id>ce4747963252a30613ebf1c1df3d83b9526a342e</id>
<content type='text'>
Pull x86 mm changes from Ingo Molnar:
 "The main change in this cycle is the rework of the TLB range flushing
  code, to simplify, fix and consolidate the code.  By Dave Hansen"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Set TLB flush tunable to sane value (33)
  x86/mm: New tunable for single vs full TLB flush
  x86/mm: Add tracepoints for TLB flushes
  x86/mm: Unify remote INVLPG code
  x86/mm: Fix missed global TLB flush stat
  x86/mm: Rip out complicated, out-of-date, buggy TLB flushing
  x86/mm: Clean up the TLB flushing code
  x86/smep: Be more informative when signalling an SMEP fault
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 mm changes from Ingo Molnar:
 "The main change in this cycle is the rework of the TLB range flushing
  code, to simplify, fix and consolidate the code.  By Dave Hansen"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Set TLB flush tunable to sane value (33)
  x86/mm: New tunable for single vs full TLB flush
  x86/mm: Add tracepoints for TLB flushes
  x86/mm: Unify remote INVLPG code
  x86/mm: Fix missed global TLB flush stat
  x86/mm: Rip out complicated, out-of-date, buggy TLB flushing
  x86/mm: Clean up the TLB flushing code
  x86/smep: Be more informative when signalling an SMEP fault
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-08-05T00:12:45+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-08-05T00:12:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e9c9eecabaa898ff3fedd98813ee4ac1a00d006a'/>
<id>e9c9eecabaa898ff3fedd98813ee4ac1a00d006a</id>
<content type='text'>
Pull x86 cpufeature updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued cleanups of CPU bugs mis-marked as 'missing features', by
     Borislav Petkov.

   - Detect the xsaves/xrstors feature and releated cleanup, by Fenghua
     Yu"

* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Kill cpu_has_mp
  x86, amd: Cleanup init_amd
  x86/cpufeature: Add bug flags to /proc/cpuinfo
  x86, cpufeature: Convert more "features" to bugs
  x86/xsaves: Detect xsaves/xrstors feature
  x86/cpufeature.h: Reformat x86 feature macros
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 cpufeature updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Continued cleanups of CPU bugs mis-marked as 'missing features', by
     Borislav Petkov.

   - Detect the xsaves/xrstors feature and releated cleanup, by Fenghua
     Yu"

* 'x86-cpufeature-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, cpu: Kill cpu_has_mp
  x86, amd: Cleanup init_amd
  x86/cpufeature: Add bug flags to /proc/cpuinfo
  x86, cpufeature: Convert more "features" to bugs
  x86/xsaves: Detect xsaves/xrstors feature
  x86/cpufeature.h: Reformat x86 feature macros
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/mm: Rip out complicated, out-of-date, buggy TLB flushing</title>
<updated>2014-07-31T15:48:50+00:00</updated>
<author>
<name>Dave Hansen</name>
<email>dave.hansen@linux.intel.com</email>
</author>
<published>2014-07-31T15:40:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=e9f4e0a9fe2723078b7a1a1169828dd46a7b2f9e'/>
<id>e9f4e0a9fe2723078b7a1a1169828dd46a7b2f9e</id>
<content type='text'>
I think the flush_tlb_mm_range() code that tries to tune the
flush sizes based on the CPU needs to get ripped out for
several reasons:

1. It is obviously buggy.  It uses mm-&gt;total_vm to judge the
   task's footprint in the TLB.  It should certainly be using
   some measure of RSS, *NOT* -&gt;total_vm since only resident
   memory can populate the TLB.
2. Haswell, and several other CPUs are missing from the
   intel_tlb_flushall_shift_set() function.  Thus, it has been
   demonstrated to bitrot quickly in practice.
3. It is plain wrong in my vm:
	[    0.037444] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
	[    0.037444] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0
	[    0.037444] tlb_flushall_shift: 6
   Which leads to it to never use invlpg.
4. The assumptions about TLB refill costs are wrong:
	http://lkml.kernel.org/r/1337782555-8088-3-git-send-email-alex.shi@intel.com
    (more on this in later patches)
5. I can not reproduce the original data: https://lkml.org/lkml/2012/5/17/59
   I believe the sample times were too short.  Running the
   benchmark in a loop yields times that vary quite a bit.

Note that this leaves us with a static ceiling of 1 page.  This
is a conservative, dumb setting, and will be revised in a later
patch.

This also removes the code which attempts to predict whether we
are flushing data or instructions.  We expect instruction flushes
to be relatively rare and not worth tuning for explicitly.

Signed-off-by: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/20140731154055.ABC88E89@viggo.jf.intel.com
Acked-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
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>
I think the flush_tlb_mm_range() code that tries to tune the
flush sizes based on the CPU needs to get ripped out for
several reasons:

1. It is obviously buggy.  It uses mm-&gt;total_vm to judge the
   task's footprint in the TLB.  It should certainly be using
   some measure of RSS, *NOT* -&gt;total_vm since only resident
   memory can populate the TLB.
2. Haswell, and several other CPUs are missing from the
   intel_tlb_flushall_shift_set() function.  Thus, it has been
   demonstrated to bitrot quickly in practice.
3. It is plain wrong in my vm:
	[    0.037444] Last level iTLB entries: 4KB 0, 2MB 0, 4MB 0
	[    0.037444] Last level dTLB entries: 4KB 0, 2MB 0, 4MB 0
	[    0.037444] tlb_flushall_shift: 6
   Which leads to it to never use invlpg.
4. The assumptions about TLB refill costs are wrong:
	http://lkml.kernel.org/r/1337782555-8088-3-git-send-email-alex.shi@intel.com
    (more on this in later patches)
5. I can not reproduce the original data: https://lkml.org/lkml/2012/5/17/59
   I believe the sample times were too short.  Running the
   benchmark in a loop yields times that vary quite a bit.

Note that this leaves us with a static ceiling of 1 page.  This
is a conservative, dumb setting, and will be revised in a later
patch.

This also removes the code which attempts to predict whether we
are flushing data or instructions.  We expect instruction flushes
to be relatively rare and not worth tuning for explicitly.

Signed-off-by: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/20140731154055.ABC88E89@viggo.jf.intel.com
Acked-by: Rik van Riel &lt;riel@redhat.com&gt;
Acked-by: Mel Gorman &lt;mgorman@suse.de&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, cpu: Fix cache topology for early P4-SMT</title>
<updated>2014-07-23T15:16:17+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2014-07-22T13:35:14+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2a2261553dd1472ca574acadbd93e12f44c4e6d5'/>
<id>2a2261553dd1472ca574acadbd93e12f44c4e6d5</id>
<content type='text'>
P4 systems with cpuid level &lt; 4 can have SMT, but the cache topology
description available (cpuid2) does not include SMP information.

Now we know that SMT shares all cache levels, and therefore we can
mark all available cache levels as shared.

We do this by setting cpu_llc_id to -&gt;phys_proc_id, since that's
the same for each SMT thread. We can do this unconditional since if
there's no SMT its still true, the one CPU shares cache with only
itself.

This fixes a problem where such CPUs report an incorrect LLC CPU mask.

This in turn fixes a crash in the scheduler where the topology was
build wrong, it assumes the LLC mask to include at least the SMT CPUs.

Cc: Josh Boyer &lt;jwboyer@redhat.com&gt;
Cc: Dietmar Eggemann &lt;dietmar.eggemann@arm.com&gt;
Tested-by: Bruno Wolff III &lt;bruno@wolff.to&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/20140722133514.GM12054@laptop.lan
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
P4 systems with cpuid level &lt; 4 can have SMT, but the cache topology
description available (cpuid2) does not include SMP information.

Now we know that SMT shares all cache levels, and therefore we can
mark all available cache levels as shared.

We do this by setting cpu_llc_id to -&gt;phys_proc_id, since that's
the same for each SMT thread. We can do this unconditional since if
there's no SMT its still true, the one CPU shares cache with only
itself.

This fixes a problem where such CPUs report an incorrect LLC CPU mask.

This in turn fixes a crash in the scheduler where the topology was
build wrong, it assumes the LLC mask to include at least the SMT CPUs.

Cc: Josh Boyer &lt;jwboyer@redhat.com&gt;
Cc: Dietmar Eggemann &lt;dietmar.eggemann@arm.com&gt;
Tested-by: Bruno Wolff III &lt;bruno@wolff.to&gt;
Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
Link: http://lkml.kernel.org/r/20140722133514.GM12054@laptop.lan
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, cpufeature: Convert more "features" to bugs</title>
<updated>2014-06-18T22:27:04+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2014-06-17T22:06:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=9b13a93df267af681a66a6a738bf1af10102da7d'/>
<id>9b13a93df267af681a66a6a738bf1af10102da7d</id>
<content type='text'>
X86_FEATURE_FXSAVE_LEAK, X86_FEATURE_11AP and
X86_FEATURE_CLFLUSH_MONITOR are not really features but synthetic bits
we use for applying different bug workarounds. Call them what they
really are, and make sure they get the proper cross-CPU behavior (OR
rather than AND).

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1403042783-23278-1-git-send-email-bp@alien8.de
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>
X86_FEATURE_FXSAVE_LEAK, X86_FEATURE_11AP and
X86_FEATURE_CLFLUSH_MONITOR are not really features but synthetic bits
we use for applying different bug workarounds. Call them what they
really are, and make sure they get the proper cross-CPU behavior (OR
rather than AND).

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1403042783-23278-1-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2014-04-02T20:15:58+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-04-02T20:15:58+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=467cbd207abdbfe29514b5804a22661ab6e80dc6'/>
<id>467cbd207abdbfe29514b5804a22661ab6e80dc6</id>
<content type='text'>
Pull x86 old platform removal from Peter Anvin:
 "This patchset removes support for several completely obsolete
  platforms, where the maintainers either have completely vanished or
  acked the removal.  For some of them it is questionable if there even
  exists functional specimens of the hardware"

Geert Uytterhoeven apparently thought this was a April Fool's pull request ;)

* 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, platforms: Remove NUMAQ
  x86, platforms: Remove SGI Visual Workstation
  x86, apic: Remove support for IBM Summit/EXA chipset
  x86, apic: Remove support for ia32-based Unisys ES7000
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 old platform removal from Peter Anvin:
 "This patchset removes support for several completely obsolete
  platforms, where the maintainers either have completely vanished or
  acked the removal.  For some of them it is questionable if there even
  exists functional specimens of the hardware"

Geert Uytterhoeven apparently thought this was a April Fool's pull request ;)

* 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86, platforms: Remove NUMAQ
  x86, platforms: Remove SGI Visual Workstation
  x86, apic: Remove support for IBM Summit/EXA chipset
  x86, apic: Remove support for ia32-based Unisys ES7000
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, cpu: Add forcepae parameter for booting PAE kernels on PAE-disabled Pentium M</title>
<updated>2014-03-20T23:31:54+00:00</updated>
<author>
<name>Chris Bainbridge</name>
<email>chris.bainbridge@gmail.com</email>
</author>
<published>2014-03-07T11:40:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=69f2366c9456d0ce784cf5aba87ee77eeadc1d5e'/>
<id>69f2366c9456d0ce784cf5aba87ee77eeadc1d5e</id>
<content type='text'>
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.

Signed-off-by: Chris Bainbridge &lt;chris.bainbridge@gmail.com&gt;
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Many Pentium M systems disable PAE but may have a functionally usable PAE
implementation. This adds the "forcepae" parameter which bypasses the boot
check for PAE, and sets the CPU as being PAE capable. Using this parameter
will taint the kernel with TAINT_CPU_OUT_OF_SPEC.

Signed-off-by: Chris Bainbridge &lt;chris.bainbridge@gmail.com&gt;
Link: http://lkml.kernel.org/r/20140307114040.GA4997@localhost
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@zytor.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, intel: Make MSR_IA32_MISC_ENABLE bit constants systematic</title>
<updated>2014-03-13T22:55:46+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-03-13T22:40:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=0b131be8d4125b32eb5b94e84f4f9dee6a0ef797'/>
<id>0b131be8d4125b32eb5b94e84f4f9dee6a0ef797</id>
<content type='text'>
Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE
with verbose but systematic ones.  Add _BIT defines for all the rest
of them, too.

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>
Replace somewhat arbitrary constants for bits in MSR_IA32_MISC_ENABLE
with verbose but systematic ones.  Add _BIT defines for all the rest
of them, too.

Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, Intel: Convert to the new bit access MSR accessors</title>
<updated>2014-03-13T22:35:09+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2014-03-09T17:05:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c0a639ad0bc6b178b46996bd1f821a04643e2bde'/>
<id>c0a639ad0bc6b178b46996bd1f821a04643e2bde</id>
<content type='text'>
... and save some lines of code.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de
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>
... and save some lines of code.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394384725-10796-4-git-send-email-bp@alien8.de
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, platforms: Remove NUMAQ</title>
<updated>2014-02-27T16:07:39+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-02-25T20:14:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=b5660ba76b41af69a0c09d434927bb4b4cadd4b1'/>
<id>b5660ba76b41af69a0c09d434927bb4b4cadd4b1</id>
<content type='text'>
The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/n/530CFD6C.7040705@zytor.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The NUMAQ support seems to be unmaintained, remove it.

Cc: Paul Gortmaker &lt;paul.gortmaker@windriver.com&gt;
Cc: David Rientjes &lt;rientjes@google.com&gt;
Acked-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Link: http://lkml.kernel.org/r/n/530CFD6C.7040705@zytor.com
</pre>
</div>
</content>
</entry>
</feed>
