<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/arch/mips, branch v3.4.110</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>MIPS: Fix enabling of DEBUG_STACKOVERFLOW</title>
<updated>2015-09-18T01:20:45+00:00</updated>
<author>
<name>James Hogan</name>
<email>james.hogan@imgtec.com</email>
</author>
<published>2015-06-04T12:25:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a5c75be0e779d38c970b4a2129c238a5bab0dad4'/>
<id>a5c75be0e779d38c970b4a2129c238a5bab0dad4</id>
<content type='text'>
commit 5f35b9cd553fd64415b563497d05a563c988dbd6 upstream.

Commit 334c86c494b9 ("MIPS: IRQ: Add stackoverflow detection") added
kernel stack overflow detection, however it only enabled it conditional
upon the preprocessor definition DEBUG_STACKOVERFLOW, which is never
actually defined. The Kconfig option is called DEBUG_STACKOVERFLOW,
which manifests to the preprocessor as CONFIG_DEBUG_STACKOVERFLOW, so
switch it to using that definition instead.

Fixes: 334c86c494b9 ("MIPS: IRQ: Add stackoverflow detection")
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Adam Jiang &lt;jiang.adam@gmail.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/10531/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5f35b9cd553fd64415b563497d05a563c988dbd6 upstream.

Commit 334c86c494b9 ("MIPS: IRQ: Add stackoverflow detection") added
kernel stack overflow detection, however it only enabled it conditional
upon the preprocessor definition DEBUG_STACKOVERFLOW, which is never
actually defined. The Kconfig option is called DEBUG_STACKOVERFLOW,
which manifests to the preprocessor as CONFIG_DEBUG_STACKOVERFLOW, so
switch it to using that definition instead.

Fixes: 334c86c494b9 ("MIPS: IRQ: Add stackoverflow detection")
Signed-off-by: James Hogan &lt;james.hogan@imgtec.com&gt;
Cc: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: Adam Jiang &lt;jiang.adam@gmail.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: http://patchwork.linux-mips.org/patch/10531/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: Hibernate: flush TLB entries earlier</title>
<updated>2015-09-18T01:20:28+00:00</updated>
<author>
<name>Huacai Chen</name>
<email>chenhc@lemote.com</email>
</author>
<published>2015-03-29T02:54:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b645f1d3617f056019c9f0bcf65e9aebdabc7e56'/>
<id>b645f1d3617f056019c9f0bcf65e9aebdabc7e56</id>
<content type='text'>
commit a843d00d038b11267279e3b5388222320f9ddc1d upstream.

We found that TLB mismatch not only happens after kernel resume, but
also happens during snapshot restore. So move it to the beginning of
swsusp_arch_suspend().

Signed-off-by: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/9621/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a843d00d038b11267279e3b5388222320f9ddc1d upstream.

We found that TLB mismatch not only happens after kernel resume, but
also happens during snapshot restore. So move it to the beginning of
swsusp_arch_suspend().

Signed-off-by: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/9621/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: Fix kernel lockup or crash after CPU offline/online</title>
<updated>2015-04-14T09:33:59+00:00</updated>
<author>
<name>Hemmo Nieminen</name>
<email>hemmo.nieminen@iki.fi</email>
</author>
<published>2015-01-15T21:01:59+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=db6c390a258149666ccee4a0bea5f8c7acb033bc'/>
<id>db6c390a258149666ccee4a0bea5f8c7acb033bc</id>
<content type='text'>
commit c7754e75100ed5e3068ac5085747f2bfc386c8d6 upstream.

As printk() invocation can cause e.g. a TLB miss, printk() cannot be
called before the exception handlers have been properly initialized.
This can happen e.g. when netconsole has been loaded as a kernel module
and the TLB table has been cleared when a CPU was offline.

Call cpu_report() in start_secondary() only after the exception handlers
have been initialized to fix this.

Without the patch the kernel will randomly either lockup or crash
after a CPU is onlined and the console driver is a module.

Signed-off-by: Hemmo Nieminen &lt;hemmo.nieminen@iki.fi&gt;
Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Cc: David Daney &lt;david.daney@cavium.com&gt;
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8953/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit c7754e75100ed5e3068ac5085747f2bfc386c8d6 upstream.

As printk() invocation can cause e.g. a TLB miss, printk() cannot be
called before the exception handlers have been properly initialized.
This can happen e.g. when netconsole has been loaded as a kernel module
and the TLB table has been cleared when a CPU was offline.

Call cpu_report() in start_secondary() only after the exception handlers
have been initialized to fix this.

Without the patch the kernel will randomly either lockup or crash
after a CPU is onlined and the console driver is a module.

Signed-off-by: Hemmo Nieminen &lt;hemmo.nieminen@iki.fi&gt;
Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Cc: David Daney &lt;david.daney@cavium.com&gt;
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8953/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: IRQ: Fix disable_irq on CPU IRQs</title>
<updated>2015-04-14T09:33:58+00:00</updated>
<author>
<name>Felix Fietkau</name>
<email>nbd@openwrt.org</email>
</author>
<published>2015-01-15T18:05:28+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d99e455e8d53d1c85ab05ac8beea4898fd78e65f'/>
<id>d99e455e8d53d1c85ab05ac8beea4898fd78e65f</id>
<content type='text'>
commit a3e6c1eff54878506b2dddcc202df9cc8180facb upstream.

If the irq_chip does not define .irq_disable, any call to disable_irq
will defer disabling the IRQ until it fires while marked as disabled.
This assumes that the handler function checks for this condition, which
handle_percpu_irq does not. In this case, calling disable_irq leads to
an IRQ storm, if the interrupt fires while disabled.

This optimization is only useful when disabling the IRQ is slow, which
is not true for the MIPS CPU IRQ.

Disable this optimization by implementing .irq_disable and .irq_enable

Signed-off-by: Felix Fietkau &lt;nbd@openwrt.org&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8949/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a3e6c1eff54878506b2dddcc202df9cc8180facb upstream.

If the irq_chip does not define .irq_disable, any call to disable_irq
will defer disabling the IRQ until it fires while marked as disabled.
This assumes that the handler function checks for this condition, which
handle_percpu_irq does not. In this case, calling disable_irq leads to
an IRQ storm, if the interrupt fires while disabled.

This optimization is only useful when disabling the IRQ is slow, which
is not true for the MIPS CPU IRQ.

Disable this optimization by implementing .irq_disable and .irq_enable

Signed-off-by: Felix Fietkau &lt;nbd@openwrt.org&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8949/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>vm: add VM_FAULT_SIGSEGV handling support</title>
<updated>2015-04-14T09:33:57+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2015-01-29T18:51:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a10ca0dbc2bcf3383fa42dcfeca055f7b5fe1106'/>
<id>a10ca0dbc2bcf3383fa42dcfeca055f7b5fe1106</id>
<content type='text'>
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Tested-by: Jan Engelhardt &lt;jengelh@inai.de&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt; # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[bwh: Backported to 3.2:
 - Adjust filenames, context
 - Drop arc, metag, nios2 and lustre changes
 - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
 - For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context in arch/power/mm/fault.c
 - apply the original change in upstream commit for s390]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 33692f27597fcab536d7cbbcc8f52905133e4aa7 upstream.

The core VM already knows about VM_FAULT_SIGBUS, but cannot return a
"you should SIGSEGV" error, because the SIGSEGV case was generally
handled by the caller - usually the architecture fault handler.

That results in lots of duplication - all the architecture fault
handlers end up doing very similar "look up vma, check permissions, do
retries etc" - but it generally works.  However, there are cases where
the VM actually wants to SIGSEGV, and applications _expect_ SIGSEGV.

In particular, when accessing the stack guard page, libsigsegv expects a
SIGSEGV.  And it usually got one, because the stack growth is handled by
that duplicated architecture fault handler.

However, when the generic VM layer started propagating the error return
from the stack expansion in commit fee7e49d4514 ("mm: propagate error
from stack expansion even for guard page"), that now exposed the
existing VM_FAULT_SIGBUS result to user space.  And user space really
expected SIGSEGV, not SIGBUS.

To fix that case, we need to add a VM_FAULT_SIGSEGV, and teach all those
duplicate architecture fault handlers about it.  They all already have
the code to handle SIGSEGV, so it's about just tying that new return
value to the existing code, but it's all a bit annoying.

This is the mindless minimal patch to do this.  A more extensive patch
would be to try to gather up the mostly shared fault handling logic into
one generic helper routine, and long-term we really should do that
cleanup.

Just from this patch, you can generally see that most architectures just
copied (directly or indirectly) the old x86 way of doing things, but in
the meantime that original x86 model has been improved to hold the VM
semaphore for shorter times etc and to handle VM_FAULT_RETRY and other
"newer" things, so it would be a good idea to bring all those
improvements to the generic case and teach other architectures about
them too.

Reported-and-tested-by: Takashi Iwai &lt;tiwai@suse.de&gt;
Tested-by: Jan Engelhardt &lt;jengelh@inai.de&gt;
Acked-by: Heiko Carstens &lt;heiko.carstens@de.ibm.com&gt; # "s390 still compiles and boots"
Cc: linux-arch@vger.kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
[bwh: Backported to 3.2:
 - Adjust filenames, context
 - Drop arc, metag, nios2 and lustre changes
 - For sh, patch both 32-bit and 64-bit implementations to use goto bad_area
 - For s390, pass int_code and trans_exc_code as arguments to do_no_context()
   and do_sigsegv()]
Signed-off-by: Ben Hutchings &lt;ben@decadent.org.uk&gt;
[lizf: Backported to 3.4:
 - adjust context in arch/power/mm/fault.c
 - apply the original change in upstream commit for s390]
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: Loongson: Make platform serial setup always built-in.</title>
<updated>2015-04-14T09:33:38+00:00</updated>
<author>
<name>Aaro Koskinen</name>
<email>aaro.koskinen@iki.fi</email>
</author>
<published>2014-11-19T23:05:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=984541bd0ff35f6b93fab8146ebf2c92dc835108'/>
<id>984541bd0ff35f6b93fab8146ebf2c92dc835108</id>
<content type='text'>
commit 26927f76499849e095714452b8a4e09350f6a3b9 upstream.

If SERIAL_8250 is compiled as a module, the platform specific setup
for Loongson will be a module too, and it will not work very well.
At least on Loongson 3 it will trigger a build failure,
since loongson_sysconf is not exported to modules.

Fix by making the platform specific serial code always built-in.

Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Reported-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: linux-mips@linux-mips.org
Cc: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Markos Chandras &lt;Markos.Chandras@imgtec.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/8533/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 26927f76499849e095714452b8a4e09350f6a3b9 upstream.

If SERIAL_8250 is compiled as a module, the platform specific setup
for Loongson will be a module too, and it will not work very well.
At least on Loongson 3 it will trigger a build failure,
since loongson_sysconf is not exported to modules.

Fix by making the platform specific serial code always built-in.

Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@iki.fi&gt;
Reported-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Cc: linux-mips@linux-mips.org
Cc: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Markos Chandras &lt;Markos.Chandras@imgtec.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/8533/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: oprofile: Fix backtrace on 64-bit kernel</title>
<updated>2015-02-02T09:05:22+00:00</updated>
<author>
<name>Aaro Koskinen</name>
<email>aaro.koskinen@nsn.com</email>
</author>
<published>2014-10-17T15:10:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a1e400a0b7da9e889a1dde76c9b761c13f3de0ab'/>
<id>a1e400a0b7da9e889a1dde76c9b761c13f3de0ab</id>
<content type='text'>
commit bbaf113a481b6ce32444c125807ad3618643ce57 upstream.

Fix incorrect cast that always results in wrong address for the new
frame on 64-bit kernels.

Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@nsn.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8110/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit bbaf113a481b6ce32444c125807ad3618643ce57 upstream.

Fix incorrect cast that always results in wrong address for the new
frame on 64-bit kernels.

Signed-off-by: Aaro Koskinen &lt;aaro.koskinen@nsn.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8110/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: tlbex: Properly fix HUGE TLB Refill exception handler</title>
<updated>2015-02-02T09:04:56+00:00</updated>
<author>
<name>David Daney</name>
<email>david.daney@cavium.com</email>
</author>
<published>2014-10-20T22:34:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e930516632e7bde53d1abc5154e9245c4b0bdb09'/>
<id>e930516632e7bde53d1abc5154e9245c4b0bdb09</id>
<content type='text'>
commit 9e0f162a36914937a937358fcb45e0609ef2bfc4 upstream.

In commit 8393c524a25609 (MIPS: tlbex: Fix a missing statement for
HUGETLB), the TLB Refill handler was fixed so that non-OCTEON targets
would work properly with huge pages.  The change was incorrect in that
it broke the OCTEON case.

The problem is shown here:

    xxx0:	df7a0000 	ld	k0,0(k1)
    .
    .
    .
    xxxc0:	df610000 	ld	at,0(k1)
    xxxc4:	335a0ff0 	andi	k0,k0,0xff0
    xxxc8:	e825ffcd 	bbit1	at,0x5,0x0
    xxxcc:	003ad82d 	daddu	k1,at,k0
    .
    .
    .

In the non-octeon case there is a destructive test for the huge PTE
bit, and then at 0, $k0 is reloaded (that is what the 8393c524a25609
patch added).

In the octeon case, we modify k1 in the branch delay slot, but we
never need k0 again, so the new load is not needed, but since k1 is
modified, if we do the load, we load from a garbage location and then
get a nested TLB Refill, which is seen in userspace as either SIGBUS
or SIGSEGV (depending on the garbage).

The real fix is to only do this reloading if it is needed, and never
where it is harmful.

Signed-off-by: David Daney &lt;david.daney@cavium.com&gt;
Cc: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8151/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 9e0f162a36914937a937358fcb45e0609ef2bfc4 upstream.

In commit 8393c524a25609 (MIPS: tlbex: Fix a missing statement for
HUGETLB), the TLB Refill handler was fixed so that non-OCTEON targets
would work properly with huge pages.  The change was incorrect in that
it broke the OCTEON case.

The problem is shown here:

    xxx0:	df7a0000 	ld	k0,0(k1)
    .
    .
    .
    xxxc0:	df610000 	ld	at,0(k1)
    xxxc4:	335a0ff0 	andi	k0,k0,0xff0
    xxxc8:	e825ffcd 	bbit1	at,0x5,0x0
    xxxcc:	003ad82d 	daddu	k1,at,k0
    .
    .
    .

In the non-octeon case there is a destructive test for the huge PTE
bit, and then at 0, $k0 is reloaded (that is what the 8393c524a25609
patch added).

In the octeon case, we modify k1 in the branch delay slot, but we
never need k0 again, so the new load is not needed, but since k1 is
modified, if we do the load, we load from a garbage location and then
get a nested TLB Refill, which is seen in userspace as either SIGBUS
or SIGSEGV (depending on the garbage).

The real fix is to only do this reloading if it is needed, and never
where it is harmful.

Signed-off-by: David Daney &lt;david.daney@cavium.com&gt;
Cc: Huacai Chen &lt;chenhc@lemote.com&gt;
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8151/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: tlbex: Fix a missing statement for HUGETLB</title>
<updated>2015-02-02T09:04:56+00:00</updated>
<author>
<name>Huacai Chen</name>
<email>chenhc@lemote.com</email>
</author>
<published>2014-07-29T06:54:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b58f0431a070f39b0e140255a26e87b3ad4557a0'/>
<id>b58f0431a070f39b0e140255a26e87b3ad4557a0</id>
<content type='text'>
commit 8393c524a25609a30129e4a8975cf3b91f6c16a5 upstream.

In commit 2c8c53e28f1 (MIPS: Optimize TLB handlers for Octeon CPUs)
build_r4000_tlb_refill_handler() is modified. But it doesn't compatible
with the original code in HUGETLB case. Because there is a copy &amp; paste
error and one line of code is missing. It is very easy to produce a bug
with LTP's hugemmap05 test.

Signed-off-by: Huacai Chen &lt;chenhc@lemote.com&gt;
Signed-off-by: Binbin Zhou &lt;zhoubb@lemote.com&gt;
Cc: John Crispin &lt;john@phrozen.org&gt;
Cc: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/7496/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8393c524a25609a30129e4a8975cf3b91f6c16a5 upstream.

In commit 2c8c53e28f1 (MIPS: Optimize TLB handlers for Octeon CPUs)
build_r4000_tlb_refill_handler() is modified. But it doesn't compatible
with the original code in HUGETLB case. Because there is a copy &amp; paste
error and one line of code is missing. It is very easy to produce a bug
with LTP's hugemmap05 test.

Signed-off-by: Huacai Chen &lt;chenhc@lemote.com&gt;
Signed-off-by: Binbin Zhou &lt;zhoubb@lemote.com&gt;
Cc: John Crispin &lt;john@phrozen.org&gt;
Cc: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang &lt;zhangfx@lemote.com&gt;
Cc: Zhangjin Wu &lt;wuzhangjin@gmail.com&gt;
Patchwork: https://patchwork.linux-mips.org/patch/7496/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: mcount: Adjust stack pointer for static trace in MIPS32</title>
<updated>2014-12-01T10:02:38+00:00</updated>
<author>
<name>Markos Chandras</name>
<email>markos.chandras@imgtec.com</email>
</author>
<published>2014-09-16T14:55:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=504c4611c9da8b2cade4a45a31376293a4d53ed1'/>
<id>504c4611c9da8b2cade4a45a31376293a4d53ed1</id>
<content type='text'>
commit 8a574cfa2652545eb95595d38ac2a0bb501af0ae upstream.

Every mcount() call in the MIPS 32-bit kernel is done as follows:

[...]
move at, ra
jal _mcount
addiu sp, sp, -8
[...]

but upon returning from the mcount() function, the stack pointer
is not adjusted properly. This is explained in details in 58b69401c797
(MIPS: Function tracer: Fix broken function tracing).

Commit ad8c396936e3 ("MIPS: Unbreak function tracer for 64-bit kernel.)
fixed the stack manipulation for 64-bit but it didn't fix it completely
for MIPS32.

Signed-off-by: Markos Chandras &lt;markos.chandras@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7792/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 8a574cfa2652545eb95595d38ac2a0bb501af0ae upstream.

Every mcount() call in the MIPS 32-bit kernel is done as follows:

[...]
move at, ra
jal _mcount
addiu sp, sp, -8
[...]

but upon returning from the mcount() function, the stack pointer
is not adjusted properly. This is explained in details in 58b69401c797
(MIPS: Function tracer: Fix broken function tracing).

Commit ad8c396936e3 ("MIPS: Unbreak function tracer for 64-bit kernel.)
fixed the stack manipulation for 64-bit but it didn't fix it completely
for MIPS32.

Signed-off-by: Markos Chandras &lt;markos.chandras@imgtec.com&gt;
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7792/
Signed-off-by: Ralf Baechle &lt;ralf@linux-mips.org&gt;
Signed-off-by: Zefan Li &lt;lizefan@huawei.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
