<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch, branch v4.18</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>lib/ubsan: remove null-pointer checks</title>
<updated>2018-08-11T03:19:58+00:00</updated>
<author>
<name>Andrey Ryabinin</name>
<email>aryabinin@virtuozzo.com</email>
</author>
<published>2018-08-11T00:23:03+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3ca17b1f3628f916f79e0ab62f1bf0e45ec9ba92'/>
<id>3ca17b1f3628f916f79e0ab62f1bf0e45ec9ba92</id>
<content type='text'>
With gcc-8 fsanitize=null become very noisy.  GCC started to complain
about things like &amp;a-&gt;b, where 'a' is NULL pointer.  There is no NULL
dereference, we just calculate address to struct member.  It's
technically undefined behavior so UBSAN is correct to report it.  But as
long as there is no real NULL-dereference, I think, we should be fine.

-fno-delete-null-pointer-checks compiler flag should protect us from any
consequences.  So let's just no use -fsanitize=null as it's not useful
for us.  If there is a real NULL-deref we will see crash.  Even if
userspace mapped something at NULL (root can do this), with things like
SMAP should catch the issue.

Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&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>
With gcc-8 fsanitize=null become very noisy.  GCC started to complain
about things like &amp;a-&gt;b, where 'a' is NULL pointer.  There is no NULL
dereference, we just calculate address to struct member.  It's
technically undefined behavior so UBSAN is correct to report it.  But as
long as there is no real NULL-dereference, I think, we should be fine.

-fno-delete-null-pointer-checks compiler flag should protect us from any
consequences.  So let's just no use -fsanitize=null as it's not useful
for us.  If there is a real NULL-deref we will see crash.  Even if
userspace mapped something at NULL (root can do this), with things like
SMAP should catch the issue.

Link: http://lkml.kernel.org/r/20180802153209.813-1-aryabinin@virtuozzo.com
Signed-off-by: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6</title>
<updated>2018-08-09T17:00:15+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-09T17:00:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=112cbae26d18e75098d95cc234cfa5059de8d479'/>
<id>112cbae26d18e75098d95cc234cfa5059de8d479</id>
<content type='text'>
Pull crypto fix from Herbert Xu:
 "This fixes a performance regression in arm64 NEON crypto as well as a
  crash in x86 aegis/morus on unsupported CPUs"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: x86/aegis,morus - Fix and simplify CPUID checks
  crypto: arm64 - revert NEON yield for fast AEAD implementations
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull crypto fix from Herbert Xu:
 "This fixes a performance regression in arm64 NEON crypto as well as a
  crash in x86 aegis/morus on unsupported CPUs"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: x86/aegis,morus - Fix and simplify CPUID checks
  crypto: arm64 - revert NEON yield for fast AEAD implementations
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: Define mb() and add memory barriers to assembler unlock sequences</title>
<updated>2018-08-08T20:13:32+00:00</updated>
<author>
<name>John David Anglin</name>
<email>dave.anglin@bell.net</email>
</author>
<published>2018-08-05T17:30:31+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fedb8da96355f5f64353625bf96dc69423ad1826'/>
<id>fedb8da96355f5f64353625bf96dc69423ad1826</id>
<content type='text'>
For years I thought all parisc machines executed loads and stores in
order. However, Jeff Law recently indicated on gcc-patches that this is
not correct. There are various degrees of out-of-order execution all the
way back to the PA7xxx processor series (hit-under-miss). The PA8xxx
series has full out-of-order execution for both integer operations, and
loads and stores.

This is described in the following article:
http://web.archive.org/web/20040214092531/http://www.cpus.hp.com/technical_references/advperf.shtml

For this reason, we need to define mb() and to insert a memory barrier
before the store unlocking spinlocks. This ensures that all memory
accesses are complete prior to unlocking. The ldcw instruction performs
the same function on entry.

Signed-off-by: John David Anglin &lt;dave.anglin@bell.net&gt;
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
For years I thought all parisc machines executed loads and stores in
order. However, Jeff Law recently indicated on gcc-patches that this is
not correct. There are various degrees of out-of-order execution all the
way back to the PA7xxx processor series (hit-under-miss). The PA8xxx
series has full out-of-order execution for both integer operations, and
loads and stores.

This is described in the following article:
http://web.archive.org/web/20040214092531/http://www.cpus.hp.com/technical_references/advperf.shtml

For this reason, we need to define mb() and to insert a memory barrier
before the store unlocking spinlocks. This ensures that all memory
accesses are complete prior to unlocking. The ldcw instruction performs
the same function on entry.

Signed-off-by: John David Anglin &lt;dave.anglin@bell.net&gt;
Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>parisc: Enable CONFIG_MLONGCALLS by default</title>
<updated>2018-08-08T20:13:22+00:00</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2018-07-28T09:47:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=66509a276c8c1d19ee3f661a41b418d101c57d29'/>
<id>66509a276c8c1d19ee3f661a41b418d101c57d29</id>
<content type='text'>
Enable the -mlong-calls compiler option by default, because otherwise in most
cases linking the vmlinux binary fails due to truncations of R_PARISC_PCREL22F
relocations. This fixes building the 64-bit defconfig.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Enable the -mlong-calls compiler option by default, because otherwise in most
cases linking the vmlinux binary fails due to truncations of R_PARISC_PCREL22F
relocations. This fixes building the 64-bit defconfig.

Cc: stable@vger.kernel.org # 4.0+
Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: x86/aegis,morus - Fix and simplify CPUID checks</title>
<updated>2018-08-07T09:51:15+00:00</updated>
<author>
<name>Ondrej Mosnacek</name>
<email>omosnace@redhat.com</email>
</author>
<published>2018-08-03T11:37:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=877ccce7cbe8409256616f5e6bdedb08ce2e82db'/>
<id>877ccce7cbe8409256616f5e6bdedb08ce2e82db</id>
<content type='text'>
It turns out I had misunderstood how the x86_match_cpu() function works.
It evaluates a logical OR of the matching conditions, not logical AND.
This caused the CPU feature checks for AEGIS to pass even if only SSE2
(but not AES-NI) was supported (or vice versa), leading to potential
crashes if something tried to use the registered algs.

This patch switches the checks to a simpler method that is used e.g. in
the Camellia x86 code.

The patch also removes the MODULE_DEVICE_TABLE declarations which
actually seem to cause the modules to be auto-loaded at boot, which is
not desired. The crypto API on-demand module loading is sufficient.

Fixes: 1d373d4e8e15 ("crypto: x86 - Add optimized AEGIS implementations")
Fixes: 6ecc9d9ff91f ("crypto: x86 - Add optimized MORUS implementations")
Signed-off-by: Ondrej Mosnacek &lt;omosnace@redhat.com&gt;
Tested-by: Milan Broz &lt;gmazyland@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It turns out I had misunderstood how the x86_match_cpu() function works.
It evaluates a logical OR of the matching conditions, not logical AND.
This caused the CPU feature checks for AEGIS to pass even if only SSE2
(but not AES-NI) was supported (or vice versa), leading to potential
crashes if something tried to use the registered algs.

This patch switches the checks to a simpler method that is used e.g. in
the Camellia x86 code.

The patch also removes the MODULE_DEVICE_TABLE declarations which
actually seem to cause the modules to be auto-loaded at boot, which is
not desired. The crypto API on-demand module loading is sufficient.

Fixes: 1d373d4e8e15 ("crypto: x86 - Add optimized AEGIS implementations")
Fixes: 6ecc9d9ff91f ("crypto: x86 - Add optimized MORUS implementations")
Signed-off-by: Ondrej Mosnacek &lt;omosnace@redhat.com&gt;
Tested-by: Milan Broz &lt;gmazyland@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: arm64 - revert NEON yield for fast AEAD implementations</title>
<updated>2018-08-07T09:26:23+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2018-07-29T14:52:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f10dc56c64bb662822475304508c1ce99f194e70'/>
<id>f10dc56c64bb662822475304508c1ce99f194e70</id>
<content type='text'>
As it turns out, checking the TIF_NEED_RESCHED flag after each
iteration results in a significant performance regression (~10%)
when running fast algorithms (i.e., ones that use special instructions
and operate in the &lt; 4 cycles per byte range) on in-order cores with
comparatively slow memory accesses such as the Cortex-A53.

Given the speed of these ciphers, and the fact that the page based
nature of the AEAD scatterwalk API guarantees that the core NEON
transform is never invoked with more than a single page's worth of
input, we can estimate the worst case duration of any resulting
scheduling blackout: on a 1 GHz Cortex-A53 running with 64k pages,
processing a page's worth of input at 4 cycles per byte results in
a delay of ~250 us, which is a reasonable upper bound.

So let's remove the yield checks from the fused AES-CCM and AES-GCM
routines entirely.

This reverts commit 7b67ae4d5ce8e2f912377f5fbccb95811a92097f and
partially reverts commit 7c50136a8aba8784f07fb66a950cc61a7f3d2ee3.

Fixes: 7c50136a8aba ("crypto: arm64/aes-ghash - yield NEON after every ...")
Fixes: 7b67ae4d5ce8 ("crypto: arm64/aes-ccm - yield NEON after every ...")
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As it turns out, checking the TIF_NEED_RESCHED flag after each
iteration results in a significant performance regression (~10%)
when running fast algorithms (i.e., ones that use special instructions
and operate in the &lt; 4 cycles per byte range) on in-order cores with
comparatively slow memory accesses such as the Cortex-A53.

Given the speed of these ciphers, and the fact that the page based
nature of the AEAD scatterwalk API guarantees that the core NEON
transform is never invoked with more than a single page's worth of
input, we can estimate the worst case duration of any resulting
scheduling blackout: on a 1 GHz Cortex-A53 running with 64k pages,
processing a page's worth of input at 4 cycles per byte results in
a delay of ~250 us, which is a reasonable upper bound.

So let's remove the yield checks from the fused AES-CCM and AES-GCM
routines entirely.

This reverts commit 7b67ae4d5ce8e2f912377f5fbccb95811a92097f and
partially reverts commit 7c50136a8aba8784f07fb66a950cc61a7f3d2ee3.

Fixes: 7c50136a8aba ("crypto: arm64/aes-ghash - yield NEON after every ...")
Fixes: 7b67ae4d5ce8 ("crypto: arm64/aes-ccm - yield NEON after every ...")
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-08-05T16:39:30+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-05T16:39:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a8c199208cd68cc2d71684d84e37e3b56a2ae640'/>
<id>a8c199208cd68cc2d71684d84e37e3b56a2ae640</id>
<content type='text'>
Pull x86 fix from Thomas Gleixner:
 "A single fix, which addresses boot failures on machines which do not
  report EBDA correctly, which can place the trampoline into reserved
  memory regions. Validating against E820 prevents that"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/compressed/64: Validate trampoline placement against E820
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 fix from Thomas Gleixner:
 "A single fix, which addresses boot failures on machines which do not
  report EBDA correctly, which can place the trampoline into reserved
  memory regions. Validating against E820 prevents that"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/compressed/64: Validate trampoline placement against E820
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2018-08-05T16:13:07+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-05T16:13:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0cdf6d4607df37804955530e153cee2d363c426e'/>
<id>0cdf6d4607df37804955530e153cee2d363c426e</id>
<content type='text'>
Pull perf fixes from Thomas Gleixner:
 "A set of fixes for perf:

  Kernel side:

   - Fix the hardcoded index of extra PCI devices on Broadwell which
     caused a resource conflict and triggered warnings on CPU hotplug.

  Tooling:

   - Update the tools copy of several files, including perf_event.h,
     powerpc's asm/unistd.h (new io_pgetevents syscall), bpf.h and x86's
     memcpy_64.s (used in 'perf bench mem'), silencing the respective
     warnings during the perf tools build.

   - Fix the build on the alpine:edge distro"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Fix hardcoded index of Broadwell extra PCI devices
  perf tools: Fix the build on the alpine:edge distro
  tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy'
  tools headers uapi: Refresh linux/bpf.h copy
  tools headers powerpc: Update asm/unistd.h copy to pick new
  tools headers uapi: Update tools's copy of linux/perf_event.h
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf fixes from Thomas Gleixner:
 "A set of fixes for perf:

  Kernel side:

   - Fix the hardcoded index of extra PCI devices on Broadwell which
     caused a resource conflict and triggered warnings on CPU hotplug.

  Tooling:

   - Update the tools copy of several files, including perf_event.h,
     powerpc's asm/unistd.h (new io_pgetevents syscall), bpf.h and x86's
     memcpy_64.s (used in 'perf bench mem'), silencing the respective
     warnings during the perf tools build.

   - Fix the build on the alpine:edge distro"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel/uncore: Fix hardcoded index of Broadwell extra PCI devices
  perf tools: Fix the build on the alpine:edge distro
  tools arch: Update arch/x86/lib/memcpy_64.S copy used in 'perf bench mem memcpy'
  tools headers uapi: Refresh linux/bpf.h copy
  tools headers powerpc: Update asm/unistd.h copy to pick new
  tools headers uapi: Update tools's copy of linux/perf_event.h
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2018-08-03T20:43:59+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-03T20:43:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0b5b1f9a78b5e1bb3c3972fcd27dc013367550f8'/>
<id>0b5b1f9a78b5e1bb3c3972fcd27dc013367550f8</id>
<content type='text'>
Pull KVM fixes from Paolo Bonzini:
 "Two vmx bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: x86: vmx: fix vpid leak
  KVM: vmx: use local variable for current_vmptr when emulating VMPTRST
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull KVM fixes from Paolo Bonzini:
 "Two vmx bugfixes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  kvm: x86: vmx: fix vpid leak
  KVM: vmx: use local variable for current_vmptr when emulating VMPTRST
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'powerpc-4.18-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux</title>
<updated>2018-08-03T17:38:21+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-03T17:38:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2ed7533cb7d657410ac29adf08d608b634e58eb0'/>
<id>2ed7533cb7d657410ac29adf08d608b634e58eb0</id>
<content type='text'>
Pull powerpc fixes from Michael Ellerman:
 "One fix for a regression in a recent TLB flush optimisation, which
  caused us to incorrectly not send TLB invalidations to coprocessors.

  Thanks to Frederic Barrat, Nicholas Piggin, Vaibhav Jain"

* tag 'powerpc-4.18-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/radix: Fix missing global invalidations when removing copro
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull powerpc fixes from Michael Ellerman:
 "One fix for a regression in a recent TLB flush optimisation, which
  caused us to incorrectly not send TLB invalidations to coprocessors.

  Thanks to Frederic Barrat, Nicholas Piggin, Vaibhav Jain"

* tag 'powerpc-4.18-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/radix: Fix missing global invalidations when removing copro
</pre>
</div>
</content>
</entry>
</feed>
