<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux.git/arch/arm64, branch v4.18</title>
<subtitle>Linux kernel source tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/'/>
<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.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>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.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 tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux</title>
<updated>2018-08-02T17:21:49+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-02T17:21:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8cda548ffba8ee67793e54d885068dd69ed6b905'/>
<id>8cda548ffba8ee67793e54d885068dd69ed6b905</id>
<content type='text'>
Pull arm64 regression fix from Will Deacon:
 "Ard found a nasty arm64 regression in 4.18 where the AES ghash/gcm
  code doesn't notify the kernel about its use of the vector registers,
  therefore potentially corrupting live user state.

  The fix is straightforward and Herbert agreed for it to go via arm64"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  crypto/arm64: aes-ce-gcm - add missing kernel_neon_begin/end pair
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull arm64 regression fix from Will Deacon:
 "Ard found a nasty arm64 regression in 4.18 where the AES ghash/gcm
  code doesn't notify the kernel about its use of the vector registers,
  therefore potentially corrupting live user state.

  The fix is straightforward and Herbert agreed for it to go via arm64"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  crypto/arm64: aes-ce-gcm - add missing kernel_neon_begin/end pair
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: do not initialize TLB stack vma's with vma_init()</title>
<updated>2018-08-01T20:43:38+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-08-01T20:43:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085'/>
<id>8b11ec1b5ffb54f71cb5a5e5c8c4d36e5d113085</id>
<content type='text'>
Commit 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and
data segments") tried to initialize various left-over ad-hoc vma's
"properly", but actually made things worse for the temporary vma's used
for TLB flushing.

vma_init() doesn't actually initialize all of the vma, just a few
fields, so doing something like

   -       struct vm_area_struct vma = { .vm_mm = tlb-&gt;mm, };
   +       struct vm_area_struct vma;
   +
   +       vma_init(&amp;vma, tlb-&gt;mm);

was actually very bad: instead of having a nicely initialized vma with
every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
with only a couple of fields initialized.  And they weren't even fields
that the code in question mostly cared about.

The flush_tlb_range() function takes a "struct vma" rather than a
"struct mm_struct", because a few architectures actually care about what
kind of range it is - being able to only do an ITLB flush if it's a
range that doesn't have data accesses enabled, for example.  And all the
normal users already have the vma for doing the range invalidation.

But a few people want to call flush_tlb_range() with a range they just
made up, so they also end up using a made-up vma.  x86 just has a
special "flush_tlb_mm_range()" function for this, but other
architectures (arm and ia64) do the "use fake vma" thing instead, and
thus got caught up in the vma_init() changes.

At the same time, the TLB flushing code really doesn't care about most
other fields in the vma, so vma_init() is just unnecessary and
pointless.

This fixes things by having an explicit "this is just an initializer for
the TLB flush" initializer macro, which is used by the arm/arm64/ia64
people who mis-use this interface with just a dummy vma.

Fixes: 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and data segments")
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Kirill Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Hugh Dickins &lt;hughd@google.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>
Commit 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and
data segments") tried to initialize various left-over ad-hoc vma's
"properly", but actually made things worse for the temporary vma's used
for TLB flushing.

vma_init() doesn't actually initialize all of the vma, just a few
fields, so doing something like

   -       struct vm_area_struct vma = { .vm_mm = tlb-&gt;mm, };
   +       struct vm_area_struct vma;
   +
   +       vma_init(&amp;vma, tlb-&gt;mm);

was actually very bad: instead of having a nicely initialized vma with
every field but "vm_mm" zeroed, you'd have an entirely uninitialized vma
with only a couple of fields initialized.  And they weren't even fields
that the code in question mostly cared about.

The flush_tlb_range() function takes a "struct vma" rather than a
"struct mm_struct", because a few architectures actually care about what
kind of range it is - being able to only do an ITLB flush if it's a
range that doesn't have data accesses enabled, for example.  And all the
normal users already have the vma for doing the range invalidation.

But a few people want to call flush_tlb_range() with a range they just
made up, so they also end up using a made-up vma.  x86 just has a
special "flush_tlb_mm_range()" function for this, but other
architectures (arm and ia64) do the "use fake vma" thing instead, and
thus got caught up in the vma_init() changes.

At the same time, the TLB flushing code really doesn't care about most
other fields in the vma, so vma_init() is just unnecessary and
pointless.

This fixes things by having an explicit "this is just an initializer for
the TLB flush" initializer macro, which is used by the arm/arm64/ia64
people who mis-use this interface with just a dummy vma.

Fixes: 2c4541e24c55 ("mm: use vma_init() to initialize VMAs on stack and data segments")
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: Kirill Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Cc: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: John Stultz &lt;john.stultz@linaro.org&gt;
Cc: Hugh Dickins &lt;hughd@google.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto/arm64: aes-ce-gcm - add missing kernel_neon_begin/end pair</title>
<updated>2018-07-31T12:20:30+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2018-07-27T12:59:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=c7513c2a2714204d3588ecaa170ae628fd0d217e'/>
<id>c7513c2a2714204d3588ecaa170ae628fd0d217e</id>
<content type='text'>
Calling pmull_gcm_encrypt_block() requires kernel_neon_begin() and
kernel_neon_end() to be used since the routine touches the NEON
register file. Add the missing calls.

Also, since NEON register contents are not preserved outside of
a kernel mode NEON region, pass the key schedule array again.

Fixes: 7c50136a8aba ("crypto: arm64/aes-ghash - yield NEON after every ...")
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Calling pmull_gcm_encrypt_block() requires kernel_neon_begin() and
kernel_neon_end() to be used since the routine touches the NEON
register file. Add the missing calls.

Also, since NEON register contents are not preserved outside of
a kernel mode NEON region, pass the key schedule array again.

Fixes: 7c50136a8aba ("crypto: arm64/aes-ghash - yield NEON after every ...")
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'akpm' (patches from Andrew)</title>
<updated>2018-07-27T17:30:47+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2018-07-27T17:30:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=864af0d40cdc82b705e3ca79cf2a57be900954b1'/>
<id>864af0d40cdc82b705e3ca79cf2a57be900954b1</id>
<content type='text'>
Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;:
  kvm, mm: account shadow page tables to kmemcg
  zswap: re-check zswap_is_full() after do zswap_shrink()
  include/linux/eventfd.h: include linux/errno.h
  mm: fix vma_is_anonymous() false-positives
  mm: use vma_init() to initialize VMAs on stack and data segments
  mm: introduce vma_init()
  mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL
  ipc/sem.c: prevent queue.status tearing in semop
  mm: disallow mappings that conflict for devm_memremap_pages()
  kasan: only select SLUB_DEBUG with SYSFS=y
  delayacct: fix crash in delayacct_blkio_end() after delayacct init failure
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton &lt;akpm@linux-foundation.org&gt;:
  kvm, mm: account shadow page tables to kmemcg
  zswap: re-check zswap_is_full() after do zswap_shrink()
  include/linux/eventfd.h: include linux/errno.h
  mm: fix vma_is_anonymous() false-positives
  mm: use vma_init() to initialize VMAs on stack and data segments
  mm: introduce vma_init()
  mm: fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL
  ipc/sem.c: prevent queue.status tearing in semop
  mm: disallow mappings that conflict for devm_memremap_pages()
  kasan: only select SLUB_DEBUG with SYSFS=y
  delayacct: fix crash in delayacct_blkio_end() after delayacct init failure
</pre>
</div>
</content>
</entry>
<entry>
<title>mm: use vma_init() to initialize VMAs on stack and data segments</title>
<updated>2018-07-27T02:38:03+00:00</updated>
<author>
<name>Kirill A. Shutemov</name>
<email>kirill.shutemov@linux.intel.com</email>
</author>
<published>2018-07-26T23:37:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2c4541e24c55e2847bede93e33d749280edd429a'/>
<id>2c4541e24c55e2847bede93e33d749280edd429a</id>
<content type='text'>
Make sure to initialize all VMAs properly, not only those which come
from vm_area_cachep.

Link: http://lkml.kernel.org/r/20180724121139.62570-3-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: &lt;stable@vger.kernel.org&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>
Make sure to initialize all VMAs properly, not only those which come
from vm_area_cachep.

Link: http://lkml.kernel.org/r/20180724121139.62570-3-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Reviewed-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Dmitry Vyukov &lt;dvyukov@google.com&gt;
Cc: Oleg Nesterov &lt;oleg@redhat.com&gt;
Cc: Andrea Arcangeli &lt;aarcange@redhat.com&gt;
Cc: &lt;stable@vger.kernel.org&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>arm64: fix vmemmap BUILD_BUG_ON() triggering on !vmemmap setups</title>
<updated>2018-07-25T12:32:30+00:00</updated>
<author>
<name>Johannes Weiner</name>
<email>hannes@cmpxchg.org</email>
</author>
<published>2018-07-23T14:18:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=7b0eb6b41a08fa1fa0d04b1c53becd62b5fbfaee'/>
<id>7b0eb6b41a08fa1fa0d04b1c53becd62b5fbfaee</id>
<content type='text'>
Arnd reports the following arm64 randconfig build error with the PSI
patches that add another page flag:

  /git/arm-soc/arch/arm64/mm/init.c: In function 'mem_init':
  /git/arm-soc/include/linux/compiler.h:357:38: error: call to
  '__compiletime_assert_618' declared with attribute error: BUILD_BUG_ON
  failed: sizeof(struct page) &gt; (1 &lt;&lt; STRUCT_PAGE_MAX_SHIFT)

The additional page flag causes other information stored in
page-&gt;flags to get bumped into their own struct page member:

  #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT &lt;=
  BITS_PER_LONG - NR_PAGEFLAGS
  #define LAST_CPUPID_WIDTH LAST_CPUPID_SHIFT
  #else
  #define LAST_CPUPID_WIDTH 0
  #endif

  #if defined(CONFIG_NUMA_BALANCING) &amp;&amp; LAST_CPUPID_WIDTH == 0
  #define LAST_CPUPID_NOT_IN_PAGE_FLAGS
  #endif

which in turn causes the struct page size to exceed the size set in
STRUCT_PAGE_MAX_SHIFT. This value is an an estimate used to size the
VMEMMAP page array according to address space and struct page size.

However, the check is performed - and triggers here - on a !VMEMMAP
config, which consumes an additional 22 page bits for the sparse
section id. When VMEMMAP is enabled, those bits are returned, cpupid
doesn't need its own member, and the page passes the VMEMMAP check.

Restrict that check to the situation it was meant to check: that we
are sizing the VMEMMAP page array correctly.

Says Arnd:

    Further experiments show that the build error already existed before,
    but was only triggered with larger values of CONFIG_NR_CPU and/or
    CONFIG_NODES_SHIFT that might be used in actual configurations but
    not in randconfig builds.

    With longer CPU and node masks, I could recreate the problem with
    kernels as old as linux-4.7 when arm64 NUMA support got added.

Reported-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Tested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: stable@vger.kernel.org
Fixes: 1a2db300348b ("arm64, numa: Add NUMA support for arm64 platforms.")
Fixes: 3e1907d5bf5a ("arm64: mm: move vmemmap region right below the linear region")
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Arnd reports the following arm64 randconfig build error with the PSI
patches that add another page flag:

  /git/arm-soc/arch/arm64/mm/init.c: In function 'mem_init':
  /git/arm-soc/include/linux/compiler.h:357:38: error: call to
  '__compiletime_assert_618' declared with attribute error: BUILD_BUG_ON
  failed: sizeof(struct page) &gt; (1 &lt;&lt; STRUCT_PAGE_MAX_SHIFT)

The additional page flag causes other information stored in
page-&gt;flags to get bumped into their own struct page member:

  #if SECTIONS_WIDTH+ZONES_WIDTH+NODES_SHIFT+LAST_CPUPID_SHIFT &lt;=
  BITS_PER_LONG - NR_PAGEFLAGS
  #define LAST_CPUPID_WIDTH LAST_CPUPID_SHIFT
  #else
  #define LAST_CPUPID_WIDTH 0
  #endif

  #if defined(CONFIG_NUMA_BALANCING) &amp;&amp; LAST_CPUPID_WIDTH == 0
  #define LAST_CPUPID_NOT_IN_PAGE_FLAGS
  #endif

which in turn causes the struct page size to exceed the size set in
STRUCT_PAGE_MAX_SHIFT. This value is an an estimate used to size the
VMEMMAP page array according to address space and struct page size.

However, the check is performed - and triggers here - on a !VMEMMAP
config, which consumes an additional 22 page bits for the sparse
section id. When VMEMMAP is enabled, those bits are returned, cpupid
doesn't need its own member, and the page passes the VMEMMAP check.

Restrict that check to the situation it was meant to check: that we
are sizing the VMEMMAP page array correctly.

Says Arnd:

    Further experiments show that the build error already existed before,
    but was only triggered with larger values of CONFIG_NR_CPU and/or
    CONFIG_NODES_SHIFT that might be used in actual configurations but
    not in randconfig builds.

    With longer CPU and node masks, I could recreate the problem with
    kernels as old as linux-4.7 when arm64 NUMA support got added.

Reported-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Tested-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: stable@vger.kernel.org
Fixes: 1a2db300348b ("arm64, numa: Add NUMA support for arm64 platforms.")
Fixes: 3e1907d5bf5a ("arm64: mm: move vmemmap region right below the linear region")
Signed-off-by: Johannes Weiner &lt;hannes@cmpxchg.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Check for errata before evaluating cpu features</title>
<updated>2018-07-25T12:30:04+00:00</updated>
<author>
<name>Dirk Mueller</name>
<email>dmueller@suse.com</email>
</author>
<published>2018-07-25T11:10:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=dc0e36581eb2da1aa3c63ceeff0f10ef1e899b2a'/>
<id>dc0e36581eb2da1aa3c63ceeff0f10ef1e899b2a</id>
<content type='text'>
Since commit d3aec8a28be3b8 ("arm64: capabilities: Restrict KPTI
detection to boot-time CPUs") we rely on errata flags being already
populated during feature enumeration. The order of errata and
features was flipped as part of commit ed478b3f9e4a ("arm64:
capabilities: Group handling of features and errata workarounds").

Return to the orginal order of errata and feature evaluation to
ensure errata flags are present during feature evaluation.

Fixes: ed478b3f9e4a ("arm64: capabilities: Group handling of
    features and errata workarounds")
CC: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
CC: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Signed-off-by: Dirk Mueller &lt;dmueller@suse.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Since commit d3aec8a28be3b8 ("arm64: capabilities: Restrict KPTI
detection to boot-time CPUs") we rely on errata flags being already
populated during feature enumeration. The order of errata and
features was flipped as part of commit ed478b3f9e4a ("arm64:
capabilities: Group handling of features and errata workarounds").

Return to the orginal order of errata and feature evaluation to
ensure errata flags are present during feature evaluation.

Fixes: ed478b3f9e4a ("arm64: capabilities: Group handling of
    features and errata workarounds")
CC: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
CC: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Signed-off-by: Dirk Mueller &lt;dmueller@suse.com&gt;
Reviewed-by: Suzuki K Poulose &lt;suzuki.poulose@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: neon: Fix function may_use_simd() return error status</title>
<updated>2018-07-11T16:02:02+00:00</updated>
<author>
<name>Yandong Zhao</name>
<email>yandong77520@gmail.com</email>
</author>
<published>2018-07-11T11:06:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux.git/commit/?id=2fd8eb4ad87104c54800ef3cea498c92eb15c78a'/>
<id>2fd8eb4ad87104c54800ef3cea498c92eb15c78a</id>
<content type='text'>
It does not matter if the caller of may_use_simd() migrates to
another cpu after the call, but it is still important that the
kernel_neon_busy percpu instance that is read matches the cpu the
task is running on at the time of the read.

This means that raw_cpu_read() is not sufficient.  kernel_neon_busy
may appear true if the caller migrates during the execution of
raw_cpu_read() and the next task to be scheduled in on the initial
cpu calls kernel_neon_begin().

This patch replaces raw_cpu_read() with this_cpu_read() to protect
against this race.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: cb84d11e1625 ("arm64: neon: Remove support for nested or hardirq kernel-mode NEON")
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Yandong Zhao &lt;yandong77520@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
It does not matter if the caller of may_use_simd() migrates to
another cpu after the call, but it is still important that the
kernel_neon_busy percpu instance that is read matches the cpu the
task is running on at the time of the read.

This means that raw_cpu_read() is not sufficient.  kernel_neon_busy
may appear true if the caller migrates during the execution of
raw_cpu_read() and the next task to be scheduled in on the initial
cpu calls kernel_neon_begin().

This patch replaces raw_cpu_read() with this_cpu_read() to protect
against this race.

Cc: &lt;stable@vger.kernel.org&gt;
Fixes: cb84d11e1625 ("arm64: neon: Remove support for nested or hardirq kernel-mode NEON")
Acked-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Reviewed-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Reviewed-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Yandong Zhao &lt;yandong77520@gmail.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
