<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/x86/kernel/cpu/amd.c, branch v4.2.7</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>Merge branch 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2015-06-23T00:59:09+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-06-23T00:59:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d70b3ef54ceaf1c7c92209f5a662a670d04cbed9'/>
<id>d70b3ef54ceaf1c7c92209f5a662a670d04cbed9</id>
<content type='text'>
Pull x86 core updates from Ingo Molnar:
 "There were so many changes in the x86/asm, x86/apic and x86/mm topics
  in this cycle that the topical separation of -tip broke down somewhat -
  so the result is a more traditional architecture pull request,
  collected into the 'x86/core' topic.

  The topics were still maintained separately as far as possible, so
  bisectability and conceptual separation should still be pretty good -
  but there were a handful of merge points to avoid excessive
  dependencies (and conflicts) that would have been poorly tested in the
  end.

  The next cycle will hopefully be much more quiet (or at least will
  have fewer dependencies).

  The main changes in this cycle were:

   * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
     Gleixner)

     - This is the second and most intrusive part of changes to the x86
       interrupt handling - full conversion to hierarchical interrupt
       domains:

          [IOAPIC domain]   -----
                                 |
          [MSI domain]      --------[Remapping domain] ----- [ Vector domain ]
                                 |   (optional)          |
          [HPET MSI domain] -----                        |
                                                         |
          [DMAR domain]     -----------------------------
                                                         |
          [Legacy domain]   -----------------------------

       This now reflects the actual hardware and allowed us to distangle
       the domain specific code from the underlying parent domain, which
       can be optional in the case of interrupt remapping.  It's a clear
       separation of functionality and removes quite some duct tape
       constructs which plugged the remap code between ioapic/msi/hpet
       and the vector management.

     - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
       injection into guests (Feng Wu)

   * x86/asm changes:

     - Tons of cleanups and small speedups, micro-optimizations.  This
       is in preparation to move a good chunk of the low level entry
       code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
       Brian Gerst)

     - Moved all system entry related code to a new home under
       arch/x86/entry/ (Ingo Molnar)

     - Removal of the fragile and ugly CFI dwarf debuginfo annotations.
       Conversion to C will reintroduce many of them - but meanwhile
       they are only getting in the way, and the upstream kernel does
       not rely on them (Ingo Molnar)

     - NOP handling refinements. (Borislav Petkov)

   * x86/mm changes:

     - Big PAT and MTRR rework: making the code more robust and
       preparing to phase out exposing direct MTRR interfaces to drivers -
       in favor of using PAT driven interfaces (Toshi Kani, Luis R
       Rodriguez, Borislav Petkov)

     - New ioremap_wt()/set_memory_wt() interfaces to support
       Write-Through cached memory mappings.  This is especially
       important for good performance on NVDIMM hardware (Toshi Kani)

   * x86/ras changes:

     - Add support for deferred errors on AMD (Aravind Gopalakrishnan)

       This is an important RAS feature which adds hardware support for
       poisoned data.  That means roughly that the hardware marks data
       which it has detected as corrupted but wasn't able to correct, as
       poisoned data and raises an APIC interrupt to signal that in the
       form of a deferred error.  It is the OS's responsibility then to
       take proper recovery action and thus prolonge system lifetime as
       far as possible.

     - Add support for Intel "Local MCE"s: upcoming CPUs will support
       CPU-local MCE interrupts, as opposed to the traditional system-
       wide broadcasted MCE interrupts (Ashok Raj)

     - Misc cleanups (Borislav Petkov)

   * x86/platform changes:

     - Intel Atom SoC updates

  ... and lots of other cleanups, fixlets and other changes - see the
  shortlog and the Git log for details"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
  x86/hpet: Use proper hpet device number for MSI allocation
  x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
  x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
  genirq: Prevent crash in irq_move_irq()
  genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
  iommu, x86: Properly handle posted interrupts for IOMMU hotplug
  iommu, x86: Provide irq_remapping_cap() interface
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Avoid migrating VT-d posted interrupts
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu: dmar: Provide helper to copy shared irte fields
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
  iommu: Add new member capability to struct irq_remap_ops
  x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
  x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
  x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 core updates from Ingo Molnar:
 "There were so many changes in the x86/asm, x86/apic and x86/mm topics
  in this cycle that the topical separation of -tip broke down somewhat -
  so the result is a more traditional architecture pull request,
  collected into the 'x86/core' topic.

  The topics were still maintained separately as far as possible, so
  bisectability and conceptual separation should still be pretty good -
  but there were a handful of merge points to avoid excessive
  dependencies (and conflicts) that would have been poorly tested in the
  end.

  The next cycle will hopefully be much more quiet (or at least will
  have fewer dependencies).

  The main changes in this cycle were:

   * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas
     Gleixner)

     - This is the second and most intrusive part of changes to the x86
       interrupt handling - full conversion to hierarchical interrupt
       domains:

          [IOAPIC domain]   -----
                                 |
          [MSI domain]      --------[Remapping domain] ----- [ Vector domain ]
                                 |   (optional)          |
          [HPET MSI domain] -----                        |
                                                         |
          [DMAR domain]     -----------------------------
                                                         |
          [Legacy domain]   -----------------------------

       This now reflects the actual hardware and allowed us to distangle
       the domain specific code from the underlying parent domain, which
       can be optional in the case of interrupt remapping.  It's a clear
       separation of functionality and removes quite some duct tape
       constructs which plugged the remap code between ioapic/msi/hpet
       and the vector management.

     - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt
       injection into guests (Feng Wu)

   * x86/asm changes:

     - Tons of cleanups and small speedups, micro-optimizations.  This
       is in preparation to move a good chunk of the low level entry
       code from assembly to C code (Denys Vlasenko, Andy Lutomirski,
       Brian Gerst)

     - Moved all system entry related code to a new home under
       arch/x86/entry/ (Ingo Molnar)

     - Removal of the fragile and ugly CFI dwarf debuginfo annotations.
       Conversion to C will reintroduce many of them - but meanwhile
       they are only getting in the way, and the upstream kernel does
       not rely on them (Ingo Molnar)

     - NOP handling refinements. (Borislav Petkov)

   * x86/mm changes:

     - Big PAT and MTRR rework: making the code more robust and
       preparing to phase out exposing direct MTRR interfaces to drivers -
       in favor of using PAT driven interfaces (Toshi Kani, Luis R
       Rodriguez, Borislav Petkov)

     - New ioremap_wt()/set_memory_wt() interfaces to support
       Write-Through cached memory mappings.  This is especially
       important for good performance on NVDIMM hardware (Toshi Kani)

   * x86/ras changes:

     - Add support for deferred errors on AMD (Aravind Gopalakrishnan)

       This is an important RAS feature which adds hardware support for
       poisoned data.  That means roughly that the hardware marks data
       which it has detected as corrupted but wasn't able to correct, as
       poisoned data and raises an APIC interrupt to signal that in the
       form of a deferred error.  It is the OS's responsibility then to
       take proper recovery action and thus prolonge system lifetime as
       far as possible.

     - Add support for Intel "Local MCE"s: upcoming CPUs will support
       CPU-local MCE interrupts, as opposed to the traditional system-
       wide broadcasted MCE interrupts (Ashok Raj)

     - Misc cleanups (Borislav Petkov)

   * x86/platform changes:

     - Intel Atom SoC updates

  ... and lots of other cleanups, fixlets and other changes - see the
  shortlog and the Git log for details"

* 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits)
  x86/hpet: Use proper hpet device number for MSI allocation
  x86/hpet: Check for irq==0 when allocating hpet MSI interrupts
  x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled
  x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled
  x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail
  genirq: Prevent crash in irq_move_irq()
  genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
  iommu, x86: Properly handle posted interrupts for IOMMU hotplug
  iommu, x86: Provide irq_remapping_cap() interface
  iommu, x86: Setup Posted-Interrupts capability for Intel iommu
  iommu, x86: Add cap_pi_support() to detect VT-d PI capability
  iommu, x86: Avoid migrating VT-d posted interrupts
  iommu, x86: Save the mode (posted or remapped) of an IRTE
  iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip
  iommu: dmar: Provide helper to copy shared irte fields
  iommu: dmar: Extend struct irte for VT-d Posted-Interrupts
  iommu: Add new member capability to struct irq_remap_ops
  x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code
  x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation
  x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry()
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/cpu/amd: Give access to the number of nodes in a physical package</title>
<updated>2015-06-18T09:16:06+00:00</updated>
<author>
<name>Aravind Gopalakrishnan</name>
<email>Aravind.Gopalakrishnan@amd.com</email>
</author>
<published>2015-06-15T08:28:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=cc2749e4095cbbcb35518fb2db5e926b85c3f25f'/>
<id>cc2749e4095cbbcb35518fb2db5e926b85c3f25f</id>
<content type='text'>
Stash the number of nodes in a physical processor package
locally and add an accessor to be called by interested parties.
The first user is the MCE injection module which uses it to find
the node base core in a package for injecting a certain type of
errors.

Signed-off-by: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
[ Rewrote the commit message, merged it with the accessor patch and unified naming. ]
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-edac &lt;linux-edac@vger.kernel.org&gt;
Cc: mchehab@osg.samsung.com
Link: http://lkml.kernel.org/r/1433868317-18417-2-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Stash the number of nodes in a physical processor package
locally and add an accessor to be called by interested parties.
The first user is the MCE injection module which uses it to find
the node base core in a package for injecting a certain type of
errors.

Signed-off-by: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
[ Rewrote the commit message, merged it with the accessor patch and unified naming. ]
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Lutomirski &lt;luto@amacapital.net&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-edac &lt;linux-edac@vger.kernel.org&gt;
Cc: mchehab@osg.samsung.com
Link: http://lkml.kernel.org/r/1433868317-18417-2-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Kill CONFIG_X86_HT</title>
<updated>2015-06-07T13:33:44+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2015-06-04T16:55:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c8e56d20f2d190d54c0615775dcb6a23c1091681'/>
<id>c8e56d20f2d190d54c0615775dcb6a23c1091681</id>
<content type='text'>
In talking to Aravind recently about making certain AMD topology
attributes available to the MCE injection module, it seemed like
that CONFIG_X86_HT thing is more or less superfluous. It is
def_bool y, depends on SMP and gets enabled in the majority of
.configs - distro and otherwise - out there.

So let's kill it and make code behind it depend directly on SMP.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
Cc: Bartosz Golaszewski &lt;bgolaszewski@baylibre.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Daniel Walter &lt;dwalter@google.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Igor Mammedov &lt;imammedo@redhat.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/1433436928-31903-18-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In talking to Aravind recently about making certain AMD topology
attributes available to the MCE injection module, it seemed like
that CONFIG_X86_HT thing is more or less superfluous. It is
def_bool y, depends on SMP and gets enabled in the majority of
.configs - distro and otherwise - out there.

So let's kill it and make code behind it depend directly on SMP.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
Cc: Bartosz Golaszewski &lt;bgolaszewski@baylibre.com&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Daniel Walter &lt;dwalter@google.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Denys Vlasenko &lt;dvlasenk@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Igor Mammedov &lt;imammedo@redhat.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Cc: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: http://lkml.kernel.org/r/1433436928-31903-18-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/cpu/amd: Set X86_FEATURE_EXTD_APICID for future processors</title>
<updated>2015-05-06T09:16:53+00:00</updated>
<author>
<name>Aravind Gopalakrishnan</name>
<email>Aravind.Gopalakrishnan@amd.com</email>
</author>
<published>2015-04-27T15:25:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b9d16a2a21aa9c264a29dd84d6f7b03581517a03'/>
<id>b9d16a2a21aa9c264a29dd84d6f7b03581517a03</id>
<content type='text'>
Decision to use a 4-bit mask or 8-bit mask in default_get_apic_id()
is controlled by setting capability bit X86_FEATURE_EXTD_APICID.

Currently, we detect extended APIC ID support by accessing Link
Transaction Control register D18F0x68 in PCI config space.

But, not even that is needed as we can safely postulate that future
AMD processors will support 8-bit APIC IDs and we can simply set that
feature bit on them, without the PCI access.

Signed-off-by: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: dave.hansen@linux.intel.com
Cc: hecmargi@upv.es
Cc: mgorman@suse.de
Link: http://lkml.kernel.org/r/1430148351-9013-1-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Decision to use a 4-bit mask or 8-bit mask in default_get_apic_id()
is controlled by setting capability bit X86_FEATURE_EXTD_APICID.

Currently, we detect extended APIC ID support by accessing Link
Transaction Control register D18F0x68 in PCI config space.

But, not even that is needed as we can safely postulate that future
AMD processors will support 8-bit APIC IDs and we can simply set that
feature bit on them, without the PCI access.

Signed-off-by: Aravind Gopalakrishnan &lt;Aravind.Gopalakrishnan@amd.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: dave.hansen@linux.intel.com
Cc: hecmargi@upv.es
Cc: mgorman@suse.de
Link: http://lkml.kernel.org/r/1430148351-9013-1-git-send-email-Aravind.Gopalakrishnan@amd.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue</title>
<updated>2015-04-27T00:57:38+00:00</updated>
<author>
<name>Andy Lutomirski</name>
<email>luto@kernel.org</email>
</author>
<published>2015-04-26T23:47:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=61f01dd941ba9e06d2bf05994450ecc3d61b6b8b'/>
<id>61f01dd941ba9e06d2bf05994450ecc3d61b6b8b</id>
<content type='text'>
AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with
SS == 0 results in an invalid usermode state in which SS is apparently
equal to __USER_DS but causes #SS if used.

Work around the issue by setting SS to __KERNEL_DS __switch_to, thus
ensuring that SYSRET never happens with SS set to NULL.

This was exposed by a recent vDSO cleanup.

Fixes: e7d6eefaaa44 x86/vdso32/syscall.S: Do not load __USER32_DS to %ss
Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Denys Vlasenko &lt;vda.linux@googlemail.com&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
AMD CPUs don't reinitialize the SS descriptor on SYSRET, so SYSRET with
SS == 0 results in an invalid usermode state in which SS is apparently
equal to __USER_DS but causes #SS if used.

Work around the issue by setting SS to __KERNEL_DS __switch_to, thus
ensuring that SYSRET never happens with SS set to NULL.

This was exposed by a recent vDSO cleanup.

Fixes: e7d6eefaaa44 x86/vdso32/syscall.S: Do not load __USER32_DS to %ss
Signed-off-by: Andy Lutomirski &lt;luto@kernel.org&gt;
Cc: Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Denys Vlasenko &lt;vda.linux@googlemail.com&gt;
Cc: Brian Gerst &lt;brgerst@gmail.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</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>2015-04-13T20:31:32+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-04-13T20:31:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6cf78d4b3766bcd25348d72377796f9566ac8e1a'/>
<id>6cf78d4b3766bcd25348d72377796f9566ac8e1a</id>
<content type='text'>
Pull x86 mm changes from Ingo Molnar:
 "The main changes in this cycle were:

   - reduce the x86/32 PAE per task PGD allocation overhead from 4K to
     0.032k (Fenghua Yu)

   - early_ioremap/memunmap() usage cleanups (Juergen Gross)

   - gbpages support cleanups (Luis R Rodriguez)

   - improve AMD Bulldozer (family 0x15) ASLR I$ aliasing workaround to
     increase randomization by 3 bits (per bootup) (Hector
     Marco-Gisbert)

   - misc fixlets"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Improve AMD Bulldozer ASLR workaround
  x86/mm/pat: Initialize __cachemode2pte_tbl[] and __pte2cachemode_tbl[] in a bit more readable fashion
  init.h: Clean up the __setup()/early_param() macros
  x86/mm: Simplify probe_page_size_mask()
  x86/mm: Further simplify 1 GB kernel linear mappings handling
  x86/mm: Use early_param_on_off() for direct_gbpages
  init.h: Add early_param_on_off()
  x86/mm: Simplify enabling direct_gbpages
  x86/mm: Use IS_ENABLED() for direct_gbpages
  x86/mm: Unexport set_memory_ro() and set_memory_rw()
  x86/mm, efi: Use early_ioremap() in arch/x86/platform/efi/efi-bgrt.c
  x86/mm: Use early_memunmap() instead of early_iounmap()
  x86/mm/pat: Ensure different messages in STRICT_DEVMEM and PAT cases
  x86/mm: Reduce PAE-mode per task pgd allocation overhead from 4K to 32 bytes
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 mm changes from Ingo Molnar:
 "The main changes in this cycle were:

   - reduce the x86/32 PAE per task PGD allocation overhead from 4K to
     0.032k (Fenghua Yu)

   - early_ioremap/memunmap() usage cleanups (Juergen Gross)

   - gbpages support cleanups (Luis R Rodriguez)

   - improve AMD Bulldozer (family 0x15) ASLR I$ aliasing workaround to
     increase randomization by 3 bits (per bootup) (Hector
     Marco-Gisbert)

   - misc fixlets"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Improve AMD Bulldozer ASLR workaround
  x86/mm/pat: Initialize __cachemode2pte_tbl[] and __pte2cachemode_tbl[] in a bit more readable fashion
  init.h: Clean up the __setup()/early_param() macros
  x86/mm: Simplify probe_page_size_mask()
  x86/mm: Further simplify 1 GB kernel linear mappings handling
  x86/mm: Use early_param_on_off() for direct_gbpages
  init.h: Add early_param_on_off()
  x86/mm: Simplify enabling direct_gbpages
  x86/mm: Use IS_ENABLED() for direct_gbpages
  x86/mm: Unexport set_memory_ro() and set_memory_rw()
  x86/mm, efi: Use early_ioremap() in arch/x86/platform/efi/efi-bgrt.c
  x86/mm: Use early_memunmap() instead of early_iounmap()
  x86/mm/pat: Ensure different messages in STRICT_DEVMEM and PAT cases
  x86/mm: Reduce PAE-mode per task pgd allocation overhead from 4K to 32 bytes
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/mm: Improve AMD Bulldozer ASLR workaround</title>
<updated>2015-03-31T08:01:17+00:00</updated>
<author>
<name>Hector Marco-Gisbert</name>
<email>hecmargi@upv.es</email>
</author>
<published>2015-03-27T11:38:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4e26d11f52684dc8b1632a8cfe450cb5197a8464'/>
<id>4e26d11f52684dc8b1632a8cfe450cb5197a8464</id>
<content type='text'>
The ASLR implementation needs to special-case AMD F15h processors by
clearing out bits [14:12] of the virtual address in order to avoid I$
cross invalidations and thus performance penalty for certain workloads.
For details, see:

  dfb09f9b7ab0 ("x86, amd: Avoid cache aliasing penalties on AMD family 15h")

This special case reduces the mmapped file's entropy by 3 bits.

The following output is the run on an AMD Opteron 62xx class CPU
processor under x86_64 Linux 4.0.0:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep "r-xp.*libc" ; done
  b7588000-b7736000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7570000-b771e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75d0000-b777e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75b0000-b775e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7578000-b7726000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  ...

Bits [12:14] are always 0, i.e. the address always ends in 0x8000 or
0x0000.

32-bit systems, as in the example above, are especially sensitive
to this issue because 32-bit randomness for VA space is 8 bits (see
mmap_rnd()). With the Bulldozer special case, this diminishes to only 32
different slots of mmap virtual addresses.

This patch randomizes per boot the three affected bits rather than
setting them to zero. Since all the shared pages have the same value
at bits [12..14], there is no cache aliasing problems. This value gets
generated during system boot and it is thus not known to a potential
remote attacker. Therefore, the impact from the Bulldozer workaround
gets diminished and ASLR randomness increased.

More details at:

  http://hmarco.org/bugs/AMD-Bulldozer-linux-ASLR-weakness-reducing-mmaped-files-by-eight.html

Original white paper by AMD dealing with the issue:

  http://developer.amd.com/wordpress/media/2012/10/SharedL1InstructionCacheonAMD15hCPU.pdf

Mentored-by: Ismael Ripoll &lt;iripoll@disca.upv.es&gt;
Signed-off-by: Hector Marco-Gisbert &lt;hecmargi@upv.es&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jan-Simon &lt;dl9pf@gmx.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-fsdevel@vger.kernel.org
Link: http://lkml.kernel.org/r/1427456301-3764-1-git-send-email-hecmargi@upv.es
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The ASLR implementation needs to special-case AMD F15h processors by
clearing out bits [14:12] of the virtual address in order to avoid I$
cross invalidations and thus performance penalty for certain workloads.
For details, see:

  dfb09f9b7ab0 ("x86, amd: Avoid cache aliasing penalties on AMD family 15h")

This special case reduces the mmapped file's entropy by 3 bits.

The following output is the run on an AMD Opteron 62xx class CPU
processor under x86_64 Linux 4.0.0:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep "r-xp.*libc" ; done
  b7588000-b7736000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7570000-b771e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75d0000-b777e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b75b0000-b775e000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  b7578000-b7726000 r-xp 00000000 00:01 4924       /lib/i386-linux-gnu/libc.so.6
  ...

Bits [12:14] are always 0, i.e. the address always ends in 0x8000 or
0x0000.

32-bit systems, as in the example above, are especially sensitive
to this issue because 32-bit randomness for VA space is 8 bits (see
mmap_rnd()). With the Bulldozer special case, this diminishes to only 32
different slots of mmap virtual addresses.

This patch randomizes per boot the three affected bits rather than
setting them to zero. Since all the shared pages have the same value
at bits [12..14], there is no cache aliasing problems. This value gets
generated during system boot and it is thus not known to a potential
remote attacker. Therefore, the impact from the Bulldozer workaround
gets diminished and ASLR randomness increased.

More details at:

  http://hmarco.org/bugs/AMD-Bulldozer-linux-ASLR-weakness-reducing-mmaped-files-by-eight.html

Original white paper by AMD dealing with the issue:

  http://developer.amd.com/wordpress/media/2012/10/SharedL1InstructionCacheonAMD15hCPU.pdf

Mentored-by: Ismael Ripoll &lt;iripoll@disca.upv.es&gt;
Signed-off-by: Hector Marco-Gisbert &lt;hecmargi@upv.es&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Acked-by: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Alexander Viro &lt;viro@zeniv.linux.org.uk&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Jan-Simon &lt;dl9pf@gmx.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: linux-fsdevel@vger.kernel.org
Link: http://lkml.kernel.org/r/1427456301-3764-1-git-send-email-hecmargi@upv.es
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/asm: Cleanup prefetch primitives</title>
<updated>2015-02-23T12:44:17+00:00</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2015-01-18T16:48:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a930dc4543a2b213deb9fde12682716edff8a4a6'/>
<id>a930dc4543a2b213deb9fde12682716edff8a4a6</id>
<content type='text'>
This is based on a patch originally by hpa.

With the current improvements to the alternatives, we can simply use %P1
as a mem8 operand constraint and rely on the toolchain to generate the
proper instruction sizes. For example, on 32-bit, where we use an empty
old instruction we get:

  apply_alternatives: feat: 6*32+8, old: (c104648b, len: 4), repl: (c195566c, len: 4)
  c104648b: alt_insn: 90 90 90 90
  c195566c: rpl_insn: 0f 0d 4b 5c

  ...

  apply_alternatives: feat: 6*32+8, old: (c18e09b4, len: 3), repl: (c1955948, len: 3)
  c18e09b4: alt_insn: 90 90 90
  c1955948: rpl_insn: 0f 0d 08

  ...

  apply_alternatives: feat: 6*32+8, old: (c1190cf9, len: 7), repl: (c1955a79, len: 7)
  c1190cf9: alt_insn: 90 90 90 90 90 90 90
  c1955a79: rpl_insn: 0f 0d 0d a0 d4 85 c1

all with the proper padding done depending on the size of the
replacement instruction the compiler generates.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This is based on a patch originally by hpa.

With the current improvements to the alternatives, we can simply use %P1
as a mem8 operand constraint and rely on the toolchain to generate the
proper instruction sizes. For example, on 32-bit, where we use an empty
old instruction we get:

  apply_alternatives: feat: 6*32+8, old: (c104648b, len: 4), repl: (c195566c, len: 4)
  c104648b: alt_insn: 90 90 90 90
  c195566c: rpl_insn: 0f 0d 4b 5c

  ...

  apply_alternatives: feat: 6*32+8, old: (c18e09b4, len: 3), repl: (c1955948, len: 3)
  c18e09b4: alt_insn: 90 90 90
  c1955948: rpl_insn: 0f 0d 08

  ...

  apply_alternatives: feat: 6*32+8, old: (c1190cf9, len: 7), repl: (c1955a79, len: 7)
  c1190cf9: alt_insn: 90 90 90 90 90 90 90
  c1955a79: rpl_insn: 0f 0d 0d a0 d4 85 c1

all with the proper padding done depending on the size of the
replacement instruction the compiler generates.

Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'perf/hw_breakpoints' into perf/core</title>
<updated>2015-01-28T14:48:59+00:00</updated>
<author>
<name>Ingo Molnar</name>
<email>mingo@kernel.org</email>
</author>
<published>2015-01-28T14:48:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b3890e4704594fa23abe1395d1fafc97d3214be8'/>
<id>b3890e4704594fa23abe1395d1fafc97d3214be8</id>
<content type='text'>
The new hw_breakpoint bits are now ready for v3.20, merge them
into the main branch, to avoid conflicts.

Conflicts:
	tools/perf/Documentation/perf-record.txt

Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The new hw_breakpoint bits are now ready for v3.20, merge them
into the main branch, to avoid conflicts.

Conflicts:
	tools/perf/Documentation/perf-record.txt

Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>perf/x86/amd: AMD support for bp_len &gt; HW_BREAKPOINT_LEN_8</title>
<updated>2014-12-03T14:14:26+00:00</updated>
<author>
<name>Jacob Shin</name>
<email>jacob.w.shin@gmail.com</email>
</author>
<published>2014-05-29T15:26:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d6d55f0b9d900673548515614b56ab55aa2c51f8'/>
<id>d6d55f0b9d900673548515614b56ab55aa2c51f8</id>
<content type='text'>
Implement hardware breakpoint address mask for AMD Family 16h and
above processors. CPUID feature bit indicates hardware support for
DRn_ADDR_MASK MSRs. These masks further qualify DRn/DR7 hardware
breakpoint addresses to allow matching of larger addresses ranges.

Valuable advice and pseudo code from Oleg Nesterov &lt;oleg@redhat.com&gt;

Signed-off-by: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Signed-off-by: Suravee Suthikulpanit &lt;suravee.suthikulpanit@amd.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Reviewed-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@ghostprotocols.net&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: xiakaixu &lt;xiakaixu@huawei.com&gt;
Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Implement hardware breakpoint address mask for AMD Family 16h and
above processors. CPUID feature bit indicates hardware support for
DRn_ADDR_MASK MSRs. These masks further qualify DRn/DR7 hardware
breakpoint addresses to allow matching of larger addresses ranges.

Valuable advice and pseudo code from Oleg Nesterov &lt;oleg@redhat.com&gt;

Signed-off-by: Jacob Shin &lt;jacob.w.shin@gmail.com&gt;
Signed-off-by: Suravee Suthikulpanit &lt;suravee.suthikulpanit@amd.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Reviewed-by: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Arnaldo Carvalho de Melo &lt;acme@ghostprotocols.net&gt;
Cc: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: xiakaixu &lt;xiakaixu@huawei.com&gt;
Signed-off-by: Frederic Weisbecker &lt;fweisbec@gmail.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
