linux-stable.git/arch, branch v4.12.2 Linux kernel stable tree x86/mm/pat: Don't report PAT on CPUs that don't support it 2017-07-15T11:09:05+00:00 Mikulas Patocka mpatocka@redhat.com 2017-07-04T23:04:23+00:00 2607611714b9ed2da7ba0d0fa3a038578dc20462 commit 99c13b8c8896d7bcb92753bf0c63a8de4326e78d upstream. The pat_enabled() logic is broken on CPUs which do not support PAT and where the initialization code fails to call pat_init(). Due to that the enabled flag stays true and pat_enabled() returns true wrongfully. As a consequence the mappings, e.g. for Xorg, are set up with the wrong caching mode and the required MTRR setups are omitted. To cure this the following changes are required: 1) Make pat_enabled() return true only if PAT initialization was invoked and successful. 2) Invoke init_cache_modes() unconditionally in setup_arch() and remove the extra callsites in pat_disable() and the pat disabled code path in pat_init(). Also rename __pat_enabled to pat_disabled to reflect the real purpose of this variable. Fixes: 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled") Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Bernhard Held <berny156@gmx.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Brian Gerst <brgerst@gmail.com> Cc: "Luis R. Rodriguez" <mcgrof@suse.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1707041749300.3456@file01.intranet.prod.int.rdu2.redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 99c13b8c8896d7bcb92753bf0c63a8de4326e78d upstream.

The pat_enabled() logic is broken on CPUs which do not support PAT and
where the initialization code fails to call pat_init(). Due to that the
enabled flag stays true and pat_enabled() returns true wrongfully.

As a consequence the mappings, e.g. for Xorg, are set up with the wrong
caching mode and the required MTRR setups are omitted.

To cure this the following changes are required:

  1) Make pat_enabled() return true only if PAT initialization was
     invoked and successful.

  2) Invoke init_cache_modes() unconditionally in setup_arch() and
     remove the extra callsites in pat_disable() and the pat disabled
     code path in pat_init().

Also rename __pat_enabled to pat_disabled to reflect the real purpose of
this variable.

Fixes: 9cd25aac1f44 ("x86/mm/pat: Emulate PAT when it is disabled")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bernhard Held <berny156@gmx.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: "Luis R. Rodriguez" <mcgrof@suse.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1707041749300.3456@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/uaccess: Optimize copy_user_enhanced_fast_string() for short strings 2017-07-12T14:55:25+00:00 Paolo Abeni pabeni@redhat.com 2017-06-29T13:55:58+00:00 1272418996e133555b963b3fb0173ca4e0ab7e47 commit 236222d39347e0e486010f10c1493e83dbbdfba8 upstream. According to the Intel datasheet, the REP MOVSB instruction exposes a pretty heavy setup cost (50 ticks), which hurts short string copy operations. This change tries to avoid this cost by calling the explicit loop available in the unrolled code for strings shorter than 64 bytes. The 64 bytes cutoff value is arbitrary from the code logic point of view - it has been selected based on measurements, as the largest value that still ensures a measurable gain. Micro benchmarks of the __copy_from_user() function with lengths in the [0-63] range show this performance gain (shorter the string, larger the gain): - in the [55%-4%] range on Intel Xeon(R) CPU E5-2690 v4 - in the [72%-9%] range on Intel Core i7-4810MQ Other tested CPUs - namely Intel Atom S1260 and AMD Opteron 8216 - show no difference, because they do not expose the ERMS feature bit. Signed-off-by: Paolo Abeni <pabeni@redhat.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hannes Frederic Sowa <hannes@stressinduktion.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/4533a1d101fd460f80e21329a34928fad521c1d4.1498744345.git.pabeni@redhat.com [ Clarified the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Mel Gorman <mgorman@techsingularity.net> 
commit 236222d39347e0e486010f10c1493e83dbbdfba8 upstream.

According to the Intel datasheet, the REP MOVSB instruction
exposes a pretty heavy setup cost (50 ticks), which hurts
short string copy operations.

This change tries to avoid this cost by calling the explicit
loop available in the unrolled code for strings shorter
than 64 bytes.

The 64 bytes cutoff value is arbitrary from the code logic
point of view - it has been selected based on measurements,
as the largest value that still ensures a measurable gain.

Micro benchmarks of the __copy_from_user() function with
lengths in the [0-63] range show this performance gain
(shorter the string, larger the gain):

 - in the [55%-4%] range on Intel Xeon(R) CPU E5-2690 v4
 - in the [72%-9%] range on Intel Core i7-4810MQ

Other tested CPUs - namely Intel Atom S1260 and AMD Opteron
8216 - show no difference, because they do not expose the
ERMS feature bit.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/4533a1d101fd460f80e21329a34928fad521c1d4.1498744345.git.pabeni@redhat.com
[ Clarified the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
powerpc/powernv: Fix CPU_HOTPLUG=n idle.c compile error 2017-07-12T14:55:24+00:00 Nicholas Piggin npiggin@gmail.com 2017-05-11T15:15:20+00:00 e1ebb00c1b02ecb3b213383c7d0494068e1126b6 commit 67d20418088680d22037119d914982cd982b5c5a upstream. Fixes: a7cd88da97 ("powerpc/powernv: Move CPU-Offline idle state invocation from smp.c to idle.c") Cc: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 67d20418088680d22037119d914982cd982b5c5a upstream.

Fixes: a7cd88da97 ("powerpc/powernv: Move CPU-Offline idle state invocation from smp.c to idle.c")
Cc: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-07-02T18:53:44+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-02T18:53:44+00:00 79c496816963aa0561868b43c2c950dfeb282639 Pull MIPS fixes from Ralf Baechle: "Here's a final round of fixes for 4.12: - Fix misordered instructions in assembly code making kenel startup via UHB unreliable. - Fix special case of MADDF and MADDF emulation. - Fix alignment issue in address calculation in pm-cps on 64 bit. - Fix IRQ tracing & lockdep when rescheduling - Systems with MAARs require post-DMA cache flushes. The reordering fix and the MADDF/MSUBF fix have sat in linux-next for a number of days. The others haven't propagated from my pull tree to linux-next yet but all have survived manual testing and Imagination's automated test system and there are no pending bug reports" * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: MIPS: Avoid accidental raw backtrace MIPS: Perform post-DMA cache flushes on systems with MAARs MIPS: Fix IRQ tracing & lockdep when rescheduling MIPS: pm-cps: Drop manual cache-line alignment of ready_count MIPS: math-emu: Handle zero accumulator case in MADDF and MSUBF separately MIPS: head: Reorder instructions missing a delay slot 
Pull MIPS fixes from Ralf Baechle:
 "Here's a final round of fixes for 4.12:

   - Fix misordered instructions in assembly code making kenel startup
     via UHB unreliable.

   - Fix special case of MADDF and MADDF emulation.

   - Fix alignment issue in address calculation in pm-cps on 64 bit.

   - Fix IRQ tracing & lockdep when rescheduling

   - Systems with MAARs require post-DMA cache flushes.

  The reordering fix and the MADDF/MSUBF fix have sat in linux-next for
  a number of days. The others haven't propagated from my pull tree to
  linux-next yet but all have survived manual testing and Imagination's
  automated test system and there are no pending bug reports"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Avoid accidental raw backtrace
  MIPS: Perform post-DMA cache flushes on systems with MAARs
  MIPS: Fix IRQ tracing & lockdep when rescheduling
  MIPS: pm-cps: Drop manual cache-line alignment of ready_count
  MIPS: math-emu: Handle zero accumulator case in MADDF and MSUBF separately
  MIPS: head: Reorder instructions missing a delay slot
Merge branch 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm 2017-07-02T17:09:40+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-02T17:09:40+00:00 3a61a54cd72c93afa3b7246e3ed06f26ed37fde7 Pull ARM fix from Russell King: "One final fix for 4.12 - Doug found a boot failure case triggered by requesting a non-even MB vmalloc size" * 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8685/1: ensure memblock-limit is pmd-aligned 
Pull ARM fix from Russell King:
 "One final fix for 4.12 - Doug found a boot failure case triggered by
  requesting a non-even MB vmalloc size"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8685/1: ensure memblock-limit is pmd-aligned
Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-07-01T16:10:17+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-07-01T16:10:17+00:00 e18aca0236a2dac4a134ace4685e97ad09d3605b Pull x86 fixes from Thomas Gleixner: "Fixlets for x86: - Prevent kexec crash when KASLR is enabled, which was caused by an address calculation bug - Restore the freeing of PUDs on memory hot remove - Correct a negated pointer check in the intel uncore performance monitoring driver - Plug a memory leak in an error exit path in the RDT code" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/intel_rdt: Fix memory leak on mount failure x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization perf/x86/intel/uncore: Fix wrong box pointer check x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD 
Pull x86 fixes from Thomas Gleixner:
 "Fixlets for x86:

   - Prevent kexec crash when KASLR is enabled, which was caused by an
     address calculation bug

   - Restore the freeing of PUDs on memory hot remove

   - Correct a negated pointer check in the intel uncore performance
     monitoring driver

   - Plug a memory leak in an error exit path in the RDT code"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/intel_rdt: Fix memory leak on mount failure
  x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug
  x86/boot/KASLR: Add checking for the offset of kernel virtual address randomization
  perf/x86/intel/uncore: Fix wrong box pointer check
  x86/mm/hotplug: Fix BUG_ON() after hot-remove by not freeing PUD
x86/intel_rdt: Fix memory leak on mount failure 2017-06-30T19:20:00+00:00 Vikas Shivappa vikas.shivappa@linux.intel.com 2017-06-26T18:55:49+00:00 79298acc4ba097e9ab78644e3e38902d73547c92 If mount fails, the kn_info directory is not freed causing memory leak. Add the missing error handling path. Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system") Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: ravi.v.shankar@intel.com Cc: tony.luck@intel.com Cc: fenghua.yu@intel.com Cc: peterz@infradead.org Cc: vikas.shivappa@intel.com Cc: andi.kleen@intel.com Cc: stable@vger.kernel.org Link: http://lkml.kernel.org/r/1498503368-20173-3-git-send-email-vikas.shivappa@linux.intel.com 
If mount fails, the kn_info directory is not freed causing memory leak.

Add the missing error handling path.

Fixes: 4e978d06dedb ("x86/intel_rdt: Add "info" files to resctrl file system")
Signed-off-by: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ravi.v.shankar@intel.com
Cc: tony.luck@intel.com
Cc: fenghua.yu@intel.com
Cc: peterz@infradead.org
Cc: vikas.shivappa@intel.com
Cc: andi.kleen@intel.com
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/1498503368-20173-3-git-send-email-vikas.shivappa@linux.intel.com
Merge tag 'powerpc-4.12-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux 2017-06-30T17:55:34+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-06-30T17:55:34+00:00 b4df2e3537bef7d867338063da56b557c50f68f2 Pull powerpc fixes from Michael Ellerman: "Hopefully the last two powerpc fixes for 4.12. The CXL one is larger than I'd usually send at rc7, but it fixes new code this cycle, so better to have it working for the release. It was actually sent a few weeks back but got blocked in testing behind another fix that was causing issues. We are still tracking one crash in v4.12-rc7, but only one person has reproduced it and the commit identified by bisect doesn't touch any of the relevant code, so I think it's 50/50 whether that commit is actually the problem or it's some code layout / toolchain issue. Two fixes for code we merged this cycle: - cxl: Fixes for Coherent Accelerator Interface Architecture 2.0 - Avoid miscompilation w/GCC 4.6.3 on 32-bit - don't inline copy_to/from_user() Thanks to Al Viro, Larry Finger, Christophe Lombard" * tag 'powerpc-4.12-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc/32: Avoid miscompilation w/GCC 4.6.3 - don't inline copy_to/from_user() cxl: Fixes for Coherent Accelerator Interface Architecture 2.0 
Pull powerpc fixes from Michael Ellerman:
 "Hopefully the last two powerpc fixes for 4.12.

  The CXL one is larger than I'd usually send at rc7, but it fixes new
  code this cycle, so better to have it working for the release. It was
  actually sent a few weeks back but got blocked in testing behind
  another fix that was causing issues.

  We are still tracking one crash in v4.12-rc7, but only one person has
  reproduced it and the commit identified by bisect doesn't touch any of
  the relevant code, so I think it's 50/50 whether that commit is
  actually the problem or it's some code layout / toolchain issue.

  Two fixes for code we merged this cycle:

   - cxl: Fixes for Coherent Accelerator Interface Architecture 2.0

   - Avoid miscompilation w/GCC 4.6.3 on 32-bit - don't inline
     copy_to/from_user()

  Thanks to Al Viro, Larry Finger, Christophe Lombard"

* tag 'powerpc-4.12-8' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/32: Avoid miscompilation w/GCC 4.6.3 - don't inline copy_to/from_user()
  cxl: Fixes for Coherent Accelerator Interface Architecture 2.0
Merge tag 'iommu-fixes-v4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu 2017-06-30T17:37:48+00:00 Linus Torvalds torvalds@linux-foundation.org 2017-06-30T17:37:48+00:00 27ab862a3afdd7a0285b69a7475f8af7bd2434c4 Pull IOMMU fixes from Joerg Roedel: "Two fixes: - A fix for AMD IOMMU interrupt remapping code when IRQs are forwarded directly to KVM guests - Fixed check in the recently merged code to allow tboot with Intel VT-d disabled" * tag 'iommu-fixes-v4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: iommu/amd: Fix interrupt remapping when disable guest_mode iommu/vt-d: Correctly disable Intel IOMMU force on 
Pull IOMMU fixes from Joerg Roedel:
 "Two fixes:

   - A fix for AMD IOMMU interrupt remapping code when IRQs are
     forwarded directly to KVM guests

   - Fixed check in the recently merged code to allow tboot with
     Intel VT-d disabled"

* tag 'iommu-fixes-v4.12-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu:
  iommu/amd: Fix interrupt remapping when disable guest_mode
  iommu/vt-d: Correctly disable Intel IOMMU force on
x86/boot/KASLR: Fix kexec crash due to 'virt_addr' calculation bug 2017-06-30T06:53:14+00:00 Baoquan He bhe@redhat.com 2017-06-27T12:39:06+00:00 8eabf42ae5237e6b699aeac687b5b629e3537c8d Kernel text KASLR is separated into physical address and virtual address randomization. And for virtual address randomization, we only randomiza to get an offset between 16M and KERNEL_IMAGE_SIZE. So the initial value of 'virt_addr' should be LOAD_PHYSICAL_ADDR, but not the original kernel loading address 'output'. The bug will cause kernel boot failure if kernel is loaded at a different position than the address, 16M, which is decided at compiled time. Kexec/kdump is such practical case. To fix it, just assign LOAD_PHYSICAL_ADDR to virt_addr as initial value. Tested-by: Dave Young <dyoung@redhat.com> Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 8391c73 ("x86/KASLR: Randomize virtual address separately") Link: http://lkml.kernel.org/r/1498567146-11990-3-git-send-email-bhe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> 
Kernel text KASLR is separated into physical address and virtual
address randomization. And for virtual address randomization, we
only randomiza to get an offset between 16M and KERNEL_IMAGE_SIZE.
So the initial value of 'virt_addr' should be LOAD_PHYSICAL_ADDR,
but not the original kernel loading address 'output'.

The bug will cause kernel boot failure if kernel is loaded at a different
position than the address, 16M, which is decided at compiled time.
Kexec/kdump is such practical case.

To fix it, just assign LOAD_PHYSICAL_ADDR to virt_addr as initial
value.

Tested-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8391c73 ("x86/KASLR: Randomize virtual address separately")
Link: http://lkml.kernel.org/r/1498567146-11990-3-git-send-email-bhe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>