<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch, branch v3.10.86</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>efi: fix 32bit kernel boot failed problem using efi</title>
<updated>2015-08-10T19:20:31+00:00</updated>
<author>
<name>Fupan Li</name>
<email>fupan.li@windriver.com</email>
</author>
<published>2015-08-04T01:51:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8492fd437ef59a2a2ed2f312466c48f202458faf'/>
<id>8492fd437ef59a2a2ed2f312466c48f202458faf</id>
<content type='text'>
Commit 35d5134b7d5a
("x86/efi: Correct EFI boot stub use of code32_start")
imported a bug, which will cause 32bit kernel boot failed
using efi method. It should use the label's address instead
of the value stored in the label to caculate the address of
code32_start.

Signed-off-by: Fupan Li &lt;fupan.li@windriver.com&gt;
Reviewed-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit 35d5134b7d5a
("x86/efi: Correct EFI boot stub use of code32_start")
imported a bug, which will cause 32bit kernel boot failed
using efi method. It should use the label's address instead
of the value stored in the label to caculate the address of
code32_start.

Signed-off-by: Fupan Li &lt;fupan.li@windriver.com&gt;
Reviewed-by: Matt Fleming &lt;matt.fleming@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tile: use free_bootmem_late() for initrd</title>
<updated>2015-08-10T19:20:30+00:00</updated>
<author>
<name>Chris Metcalf</name>
<email>cmetcalf@ezchip.com</email>
</author>
<published>2015-07-23T18:11:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=9fbf45ec96502ed1f3d6498c142e7e18f0cec9b2'/>
<id>9fbf45ec96502ed1f3d6498c142e7e18f0cec9b2</id>
<content type='text'>
commit 3f81d2447b37ac697b3c600039f2c6b628c06e21 upstream.

We were previously using free_bootmem() and just getting lucky
that nothing too bad happened.

Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 3f81d2447b37ac697b3c600039f2c6b628c06e21 upstream.

We were previously using free_bootmem() and just getting lucky
that nothing too bad happened.

Signed-off-by: Chris Metcalf &lt;cmetcalf@ezchip.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: make sure instruction_pointer() returns unsigned value</title>
<updated>2015-08-10T19:20:30+00:00</updated>
<author>
<name>Alexey Brodkin</name>
<email>abrodkin@synopsys.com</email>
</author>
<published>2015-07-13T07:25:17+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=508a750fe6cc950bad1cca07f1637ce4815b5420'/>
<id>508a750fe6cc950bad1cca07f1637ce4815b5420</id>
<content type='text'>
commit f51e2f1911122879eefefa4c592dea8bf794b39c upstream.

Currently instruction_pointer() returns pt_regs-&gt;ret and so return value
is of type "long", which implicitly stands for "signed long".

While that's perfectly fine when dealing with 32-bit values if return
value of instruction_pointer() gets assigned to 64-bit variable sign
extension may happen.

And at least in one real use-case it happens already.
In perf_prepare_sample() return value of perf_instruction_pointer()
(which is an alias to instruction_pointer() in case of ARC) is assigned
to (struct perf_sample_data)-&gt;ip (which type is "u64").

And what we see if instuction pointer points to user-space application
that in case of ARC lays below 0x8000_0000 "ip" gets set properly with
leading 32 zeros. But if instruction pointer points to kernel address
space that starts from 0x8000_0000 then "ip" is set with 32 leadig
"f"-s. I.e. id instruction_pointer() returns 0x8100_0000, "ip" will be
assigned with 0xffff_ffff__8100_0000. Which is obviously wrong.

In particular that issuse broke output of perf, because perf was unable
to associate addresses like 0xffff_ffff__8100_0000 with anything from
/proc/kallsyms.

That's what we used to see:
 -----------&gt;8----------
  6.27%  ls       [unknown]                [k] 0xffffffff8046c5cc
  2.96%  ls       libuClibc-0.9.34-git.so  [.] memcpy
  2.25%  ls       libuClibc-0.9.34-git.so  [.] memset
  1.66%  ls       [unknown]                [k] 0xffffffff80666536
  1.54%  ls       libuClibc-0.9.34-git.so  [.] 0x000224d6
  1.18%  ls       libuClibc-0.9.34-git.so  [.] 0x00022472
 -----------&gt;8----------

With that change perf output looks much better now:
 -----------&gt;8----------
  8.21%  ls       [kernel.kallsyms]        [k] memset
  3.52%  ls       libuClibc-0.9.34-git.so  [.] memcpy
  2.11%  ls       libuClibc-0.9.34-git.so  [.] malloc
  1.88%  ls       libuClibc-0.9.34-git.so  [.] memset
  1.64%  ls       [kernel.kallsyms]        [k] _raw_spin_unlock_irqrestore
  1.41%  ls       [kernel.kallsyms]        [k] __d_lookup_rcu
 -----------&gt;8----------

Signed-off-by: Alexey Brodkin &lt;abrodkin@synopsys.com&gt;
Cc: arc-linux-dev@synopsys.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f51e2f1911122879eefefa4c592dea8bf794b39c upstream.

Currently instruction_pointer() returns pt_regs-&gt;ret and so return value
is of type "long", which implicitly stands for "signed long".

While that's perfectly fine when dealing with 32-bit values if return
value of instruction_pointer() gets assigned to 64-bit variable sign
extension may happen.

And at least in one real use-case it happens already.
In perf_prepare_sample() return value of perf_instruction_pointer()
(which is an alias to instruction_pointer() in case of ARC) is assigned
to (struct perf_sample_data)-&gt;ip (which type is "u64").

And what we see if instuction pointer points to user-space application
that in case of ARC lays below 0x8000_0000 "ip" gets set properly with
leading 32 zeros. But if instruction pointer points to kernel address
space that starts from 0x8000_0000 then "ip" is set with 32 leadig
"f"-s. I.e. id instruction_pointer() returns 0x8100_0000, "ip" will be
assigned with 0xffff_ffff__8100_0000. Which is obviously wrong.

In particular that issuse broke output of perf, because perf was unable
to associate addresses like 0xffff_ffff__8100_0000 with anything from
/proc/kallsyms.

That's what we used to see:
 -----------&gt;8----------
  6.27%  ls       [unknown]                [k] 0xffffffff8046c5cc
  2.96%  ls       libuClibc-0.9.34-git.so  [.] memcpy
  2.25%  ls       libuClibc-0.9.34-git.so  [.] memset
  1.66%  ls       [unknown]                [k] 0xffffffff80666536
  1.54%  ls       libuClibc-0.9.34-git.so  [.] 0x000224d6
  1.18%  ls       libuClibc-0.9.34-git.so  [.] 0x00022472
 -----------&gt;8----------

With that change perf output looks much better now:
 -----------&gt;8----------
  8.21%  ls       [kernel.kallsyms]        [k] memset
  3.52%  ls       libuClibc-0.9.34-git.so  [.] memcpy
  2.11%  ls       libuClibc-0.9.34-git.so  [.] malloc
  1.88%  ls       libuClibc-0.9.34-git.so  [.] memset
  1.64%  ls       [kernel.kallsyms]        [k] _raw_spin_unlock_irqrestore
  1.41%  ls       [kernel.kallsyms]        [k] __d_lookup_rcu
 -----------&gt;8----------

Signed-off-by: Alexey Brodkin &lt;abrodkin@synopsys.com&gt;
Cc: arc-linux-dev@synopsys.com
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>s390/sclp: clear upper register halves in _sclp_print_early</title>
<updated>2015-08-10T19:20:29+00:00</updated>
<author>
<name>Martin Schwidefsky</name>
<email>schwidefsky@de.ibm.com</email>
</author>
<published>2015-07-06T15:58:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3a893ef1923c6f93ca477ff583efe893ff98a109'/>
<id>3a893ef1923c6f93ca477ff583efe893ff98a109</id>
<content type='text'>
commit f9c87a6f46d508eae0d9ae640be98d50f237f827 upstream.

If the kernel is compiled with gcc 5.1 and the XZ compression option
the decompress_kernel function calls _sclp_print_early in 64-bit mode
while the content of the upper register half of %r6 is non-zero.
This causes a specification exception on the servc instruction in
_sclp_servc.

The _sclp_print_early function saves and restores the upper registers
halves but it fails to clear them for the 31-bit code of the mini sclp
driver.

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f9c87a6f46d508eae0d9ae640be98d50f237f827 upstream.

If the kernel is compiled with gcc 5.1 and the XZ compression option
the decompress_kernel function calls _sclp_print_early in 64-bit mode
while the content of the upper register half of %r6 is non-zero.
This causes a specification exception on the servc instruction in
_sclp_servc.

The _sclp_print_early function saves and restores the upper registers
halves but it fails to clear them for the 31-bit code of the mini sclp
driver.

Signed-off-by: Martin Schwidefsky &lt;schwidefsky@de.ibm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: KVM: Do not sign extend on unsigned MMIO load</title>
<updated>2015-08-03T16:29:47+00:00</updated>
<author>
<name>Nicholas Mc Guire</name>
<email>hofrat@osadl.org</email>
</author>
<published>2015-05-07T12:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=79af5d9f9b3d8180b75e0cc13fa331603342a6f1'/>
<id>79af5d9f9b3d8180b75e0cc13fa331603342a6f1</id>
<content type='text'>
commit ed9244e6c534612d2b5ae47feab2f55a0d4b4ced upstream.

Fix possible unintended sign extension in unsigned MMIO loads by casting
to uint16_t in the case of mmio_needed != 2.

Signed-off-by: Nicholas Mc Guire &lt;hofrat@osadl.org&gt;
Reviewed-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Tested-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9985/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit ed9244e6c534612d2b5ae47feab2f55a0d4b4ced upstream.

Fix possible unintended sign extension in unsigned MMIO loads by casting
to uint16_t in the case of mmio_needed != 2.

Signed-off-by: Nicholas Mc Guire &lt;hofrat@osadl.org&gt;
Reviewed-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Tested-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Gleb Natapov &lt;gleb@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9985/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: vdso: work-around broken ELF toolchains in Makefile</title>
<updated>2015-08-03T16:29:41+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2015-06-19T12:56:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=6ec153c599f17f93afb650b42922379735196602'/>
<id>6ec153c599f17f93afb650b42922379735196602</id>
<content type='text'>
commit 6f1a6ae87c0c60d7c462ef8fd071f291aa7a9abb upstream.

When building the kernel with a bare-metal (ELF) toolchain, the -shared
option may not be passed down to collect2, resulting in silent corruption
of the vDSO image (in particular, the DYNAMIC section is omitted).

The effect of this corruption is that the dynamic linker fails to find
the vDSO symbols and libc is instead used for the syscalls that we
intended to optimise (e.g. gettimeofday). Functionally, there is no
issue as the sigreturn trampoline is still intact and located by the
kernel.

This patch fixes the problem by explicitly passing -shared to the linker
when building the vDSO.

Reported-by: Szabolcs Nagy &lt;Szabolcs.Nagy@arm.com&gt;
Reported-by: James Greenlaigh &lt;james.greenhalgh@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6f1a6ae87c0c60d7c462ef8fd071f291aa7a9abb upstream.

When building the kernel with a bare-metal (ELF) toolchain, the -shared
option may not be passed down to collect2, resulting in silent corruption
of the vDSO image (in particular, the DYNAMIC section is omitted).

The effect of this corruption is that the dynamic linker fails to find
the vDSO symbols and libc is instead used for the syscalls that we
intended to optimise (e.g. gettimeofday). Functionally, there is no
issue as the sigreturn trampoline is still intact and located by the
kernel.

This patch fixes the problem by explicitly passing -shared to the linker
when building the vDSO.

Reported-by: Szabolcs Nagy &lt;Szabolcs.Nagy@arm.com&gt;
Reported-by: James Greenlaigh &lt;james.greenhalgh@arm.com&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: mm: Fix freeing of the wrong memmap entries with !SPARSEMEM_VMEMMAP</title>
<updated>2015-08-03T16:29:41+00:00</updated>
<author>
<name>Dave P Martin</name>
<email>Dave.Martin@arm.com</email>
</author>
<published>2015-06-16T16:38:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=39ae2d098ad5cb37ce664d758ee9c3fc449a4940'/>
<id>39ae2d098ad5cb37ce664d758ee9c3fc449a4940</id>
<content type='text'>
commit b9bcc919931611498e856eae9bf66337330d04cc upstream.

The memmap freeing code in free_unused_memmap() computes the end of
each memblock by adding the memblock size onto the base.  However,
if SPARSEMEM is enabled then the value (start) used for the base
may already have been rounded downwards to work out which memmap
entries to free after the previous memblock.

This may cause memmap entries that are in use to get freed.

In general, you're not likely to hit this problem unless there
are at least 2 memblocks and one of them is not aligned to a
sparsemem section boundary.  Note that carve-outs can increase
the number of memblocks by splitting the regions listed in the
device tree.

This problem doesn't occur with SPARSEMEM_VMEMMAP, because the
vmemmap code deals with freeing the unused regions of the memmap
instead of requiring the arch code to do it.

This patch gets the memblock base out of the memblock directly when
computing the block end address to ensure the correct value is used.

Signed-off-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b9bcc919931611498e856eae9bf66337330d04cc upstream.

The memmap freeing code in free_unused_memmap() computes the end of
each memblock by adding the memblock size onto the base.  However,
if SPARSEMEM is enabled then the value (start) used for the base
may already have been rounded downwards to work out which memmap
entries to free after the previous memblock.

This may cause memmap entries that are in use to get freed.

In general, you're not likely to hit this problem unless there
are at least 2 memblocks and one of them is not aligned to a
sparsemem section boundary.  Note that carve-outs can increase
the number of memblocks by splitting the regions listed in the
device tree.

This problem doesn't occur with SPARSEMEM_VMEMMAP, because the
vmemmap code deals with freeing the unused regions of the memmap
instead of requiring the arch code to do it.

This patch gets the memblock base out of the memblock directly when
computing the block end address to ensure the correct value is used.

Signed-off-by: Dave Martin &lt;Dave.Martin@arm.com&gt;
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>arm64: Do not attempt to use init_mm in reset_context()</title>
<updated>2015-08-03T16:29:41+00:00</updated>
<author>
<name>Catalin Marinas</name>
<email>catalin.marinas@arm.com</email>
</author>
<published>2015-06-12T10:24:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2b97cbc8c4e7d0f06b49695636306b65bed20cf2'/>
<id>2b97cbc8c4e7d0f06b49695636306b65bed20cf2</id>
<content type='text'>
commit 565630d503ef24e44c252bed55571b3a0d68455f upstream.

After secondary CPU boot or hotplug, the active_mm of the idle thread is
&amp;init_mm. The init_mm.pgd (swapper_pg_dir) is only meant for TTBR1_EL1
and must not be set in TTBR0_EL1. Since when active_mm == &amp;init_mm the
TTBR0_EL1 is already set to the reserved value, there is no need to
perform any context reset.

Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 565630d503ef24e44c252bed55571b3a0d68455f upstream.

After secondary CPU boot or hotplug, the active_mm of the idle thread is
&amp;init_mm. The init_mm.pgd (swapper_pg_dir) is only meant for TTBR1_EL1
and must not be set in TTBR0_EL1. Since when active_mm == &amp;init_mm the
TTBR0_EL1 is already set to the reserved value, there is no need to
perform any context reset.

Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARC: add compiler barrier to LLSC based cmpxchg</title>
<updated>2015-08-03T16:29:41+00:00</updated>
<author>
<name>Vineet Gupta</name>
<email>vgupta@synopsys.com</email>
</author>
<published>2014-11-13T10:24:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ea207ff62ff67ce30e1a5d19c162a2a17f4d62dc'/>
<id>ea207ff62ff67ce30e1a5d19c162a2a17f4d62dc</id>
<content type='text'>
commit d57f727264f1425a94689bafc7e99e502cb135b5 upstream.

When auditing cmpxchg call sites, Chuck noted that gcc was optimizing
away some of the desired LDs.

|	do {
|		new = old = *ipi_data_ptr;
|		new |= 1U &lt;&lt; msg;
|	} while (cmpxchg(ipi_data_ptr, old, new) != old);

was generating to below

| 8015cef8:	ld         r2,[r4,0]  &lt;-- First LD
| 8015cefc:	bset       r1,r2,r1
|
| 8015cf00:	llock      r3,[r4]  &lt;-- atomic op
| 8015cf04:	brne       r3,r2,8015cf10
| 8015cf08:	scond      r1,[r4]
| 8015cf0c:	bnz        8015cf00
|
| 8015cf10:	brne       r3,r2,8015cf00  &lt;-- Branch doesn't go to orig LD

Although this was fixed by adding a ACCESS_ONCE in this call site, it
seems safer (for now at least) to add compiler barrier to LLSC based
cmpxchg

Reported-by: Chuck Jordan &lt;cjordan@synopsys.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit d57f727264f1425a94689bafc7e99e502cb135b5 upstream.

When auditing cmpxchg call sites, Chuck noted that gcc was optimizing
away some of the desired LDs.

|	do {
|		new = old = *ipi_data_ptr;
|		new |= 1U &lt;&lt; msg;
|	} while (cmpxchg(ipi_data_ptr, old, new) != old);

was generating to below

| 8015cef8:	ld         r2,[r4,0]  &lt;-- First LD
| 8015cefc:	bset       r1,r2,r1
|
| 8015cf00:	llock      r3,[r4]  &lt;-- atomic op
| 8015cf04:	brne       r3,r2,8015cf10
| 8015cf08:	scond      r1,[r4]
| 8015cf0c:	bnz        8015cf00
|
| 8015cf10:	brne       r3,r2,8015cf00  &lt;-- Branch doesn't go to orig LD

Although this was fixed by adding a ACCESS_ONCE in this call site, it
seems safer (for now at least) to add compiler barrier to LLSC based
cmpxchg

Reported-by: Chuck Jordan &lt;cjordan@synopsys.com&gt;
Acked-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Vineet Gupta &lt;vgupta@synopsys.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: x86: make vapics_in_nmi_mode atomic</title>
<updated>2015-07-10T17:40:22+00:00</updated>
<author>
<name>Radim Krčmář</name>
<email>rkrcmar@redhat.com</email>
</author>
<published>2015-07-01T13:31:49+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=455aa7c4b828827944a2b24df33de9b64b8d18cb'/>
<id>455aa7c4b828827944a2b24df33de9b64b8d18cb</id>
<content type='text'>
commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream.

Writes were a bit racy, but hard to turn into a bug at the same time.
(Particularly because modern Linux doesn't use this feature anymore.)

Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
[Actually the next patch makes it much, much easier to trigger the race
 so I'm including this one for stable@ as well. - Paolo]
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 42720138b06301cc8a7ee8a495a6d021c4b6a9bc upstream.

Writes were a bit racy, but hard to turn into a bug at the same time.
(Particularly because modern Linux doesn't use this feature anymore.)

Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
[Actually the next patch makes it much, much easier to trigger the race
 so I'm including this one for stable@ as well. - Paolo]
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
</feed>
