<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch, branch v3.12.15</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>arm64: mm: Add double logical invert to pte accessors</title>
<updated>2014-03-24T08:45:07+00:00</updated>
<author>
<name>Steve Capper</name>
<email>steve.capper@linaro.org</email>
</author>
<published>2014-02-25T11:38:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=3eb3391260f086f2c79252d94c7ac777dac51bd5'/>
<id>3eb3391260f086f2c79252d94c7ac777dac51bd5</id>
<content type='text'>
commit 84fe6826c28f69d8708bd575faed7f75e6b6f57f upstream.

Page table entries on ARM64 are 64 bits, and some pte functions such as
pte_dirty return a bitwise-and of a flag with the pte value. If the
flag to be tested resides in the upper 32 bits of the pte, then we run
into the danger of the result being dropped if downcast.

For example:
	gather_stats(page, md, pte_dirty(*pte), 1);
where pte_dirty(*pte) is downcast to an int.

This patch adds a double logical invert to all the pte_ accessors to
ensure predictable downcasting.

Signed-off-by: Steve Capper &lt;steve.capper@linaro.org&gt;
[steve.capper@linaro.org: rebased patch to leave pte_write alone to
allow for merge with 3.13 stable]
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 84fe6826c28f69d8708bd575faed7f75e6b6f57f upstream.

Page table entries on ARM64 are 64 bits, and some pte functions such as
pte_dirty return a bitwise-and of a flag with the pte value. If the
flag to be tested resides in the upper 32 bits of the pte, then we run
into the danger of the result being dropped if downcast.

For example:
	gather_stats(page, md, pte_dirty(*pte), 1);
where pte_dirty(*pte) is downcast to an int.

This patch adds a double logical invert to all the pte_ accessors to
ensure predictable downcasting.

Signed-off-by: Steve Capper &lt;steve.capper@linaro.org&gt;
[steve.capper@linaro.org: rebased patch to leave pte_write alone to
allow for merge with 3.13 stable]
Signed-off-by: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>MIPS: include linux/types.h</title>
<updated>2014-03-24T08:45:06+00:00</updated>
<author>
<name>Qais Yousef</name>
<email>qais.yousef@imgtec.com</email>
</author>
<published>2013-12-09T09:49:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=cf9fca41e523e859aadb6ae78a9502662f9fc7a1'/>
<id>cf9fca41e523e859aadb6ae78a9502662f9fc7a1</id>
<content type='text'>
commit 87c99203fea897fbdd84b681ad9fced2517dcf98 upstream.

The file uses u16 type but doesn't include its definition explicitly

I was getting this error when including this header in my driver:

  arch/mips/include/asm/mipsregs.h:644:33: error: unknown type name ‘u16’

Signed-off-by: Qais Yousef &lt;qais.yousef@imgtec.com&gt;
Reviewed-by: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Acked-by: David Daney &lt;david.daney@cavium.com&gt;
Signed-off-by: John Crispin &lt;blogic@openwrt.org&gt;
Patchwork: http://patchwork.linux-mips.org/patch/6212/
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 87c99203fea897fbdd84b681ad9fced2517dcf98 upstream.

The file uses u16 type but doesn't include its definition explicitly

I was getting this error when including this header in my driver:

  arch/mips/include/asm/mipsregs.h:644:33: error: unknown type name ‘u16’

Signed-off-by: Qais Yousef &lt;qais.yousef@imgtec.com&gt;
Reviewed-by: Steven J. Hill &lt;Steven.Hill@imgtec.com&gt;
Acked-by: David Daney &lt;david.daney@cavium.com&gt;
Signed-off-by: John Crispin &lt;blogic@openwrt.org&gt;
Patchwork: http://patchwork.linux-mips.org/patch/6212/
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86, fpu: Check tsk_used_math() in kernel_fpu_end() for eager FPU</title>
<updated>2014-03-24T08:45:05+00:00</updated>
<author>
<name>Suresh Siddha</name>
<email>sbsiddha@gmail.com</email>
</author>
<published>2014-02-03T06:56:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=41531218f30582610b5b2bdd16246526792b0cbe'/>
<id>41531218f30582610b5b2bdd16246526792b0cbe</id>
<content type='text'>
commit 731bd6a93a6e9172094a2322bd0ee964bb1f4d63 upstream.

For non-eager fpu mode, thread's fpu state is allocated during the first
fpu usage (in the context of device not available exception). This
(math_state_restore()) can be a blocking call and hence we enable
interrupts (which were originally disabled when the exception happened),
allocate memory and disable interrupts etc.

But the eager-fpu mode, call's the same math_state_restore() from
kernel_fpu_end(). The assumption being that tsk_used_math() is always
set for the eager-fpu mode and thus avoid the code path of enabling
interrupts, allocating fpu state using blocking call and disable
interrupts etc.

But the below issue was noticed by Maarten Baert, Nate Eldredge and
few others:

If a user process dumps core on an ecrypt fs while aesni-intel is loaded,
we get a BUG() in __find_get_block() complaining that it was called with
interrupts disabled; then all further accesses to our ecrypt fs hang
and we have to reboot.

The aesni-intel code (encrypting the core file that we are writing) needs
the FPU and quite properly wraps its code in kernel_fpu_{begin,end}(),
the latter of which calls math_state_restore(). So after kernel_fpu_end(),
interrupts may be disabled, which nobody seems to expect, and they stay
that way until we eventually get to __find_get_block() which barfs.

For eager fpu, most the time, tsk_used_math() is true. At few instances
during thread exit, signal return handling etc, tsk_used_math() might
be false.

In kernel_fpu_end(), for eager-fpu, call math_state_restore()
only if tsk_used_math() is set. Otherwise, don't bother. Kernel code
path which cleared tsk_used_math() knows what needs to be done
with the fpu state.

Reported-by: Maarten Baert &lt;maarten-baert@hotmail.com&gt;
Reported-by: Nate Eldredge &lt;nate@thatsmathematics.com&gt;
Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Suresh Siddha &lt;sbsiddha@gmail.com&gt;
Link: http://lkml.kernel.org/r/1391410583.3801.6.camel@europa
Cc: George Spelvin &lt;linux@horizon.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 731bd6a93a6e9172094a2322bd0ee964bb1f4d63 upstream.

For non-eager fpu mode, thread's fpu state is allocated during the first
fpu usage (in the context of device not available exception). This
(math_state_restore()) can be a blocking call and hence we enable
interrupts (which were originally disabled when the exception happened),
allocate memory and disable interrupts etc.

But the eager-fpu mode, call's the same math_state_restore() from
kernel_fpu_end(). The assumption being that tsk_used_math() is always
set for the eager-fpu mode and thus avoid the code path of enabling
interrupts, allocating fpu state using blocking call and disable
interrupts etc.

But the below issue was noticed by Maarten Baert, Nate Eldredge and
few others:

If a user process dumps core on an ecrypt fs while aesni-intel is loaded,
we get a BUG() in __find_get_block() complaining that it was called with
interrupts disabled; then all further accesses to our ecrypt fs hang
and we have to reboot.

The aesni-intel code (encrypting the core file that we are writing) needs
the FPU and quite properly wraps its code in kernel_fpu_{begin,end}(),
the latter of which calls math_state_restore(). So after kernel_fpu_end(),
interrupts may be disabled, which nobody seems to expect, and they stay
that way until we eventually get to __find_get_block() which barfs.

For eager fpu, most the time, tsk_used_math() is true. At few instances
during thread exit, signal return handling etc, tsk_used_math() might
be false.

In kernel_fpu_end(), for eager-fpu, call math_state_restore()
only if tsk_used_math() is set. Otherwise, don't bother. Kernel code
path which cleared tsk_used_math() knows what needs to be done
with the fpu state.

Reported-by: Maarten Baert &lt;maarten-baert@hotmail.com&gt;
Reported-by: Nate Eldredge &lt;nate@thatsmathematics.com&gt;
Suggested-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Suresh Siddha &lt;sbsiddha@gmail.com&gt;
Link: http://lkml.kernel.org/r/1391410583.3801.6.camel@europa
Cc: George Spelvin &lt;linux@horizon.com&gt;
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>KVM: SVM: fix cr8 intercept window</title>
<updated>2014-03-24T08:44:56+00:00</updated>
<author>
<name>Radim Krčmář</name>
<email>rkrcmar@redhat.com</email>
</author>
<published>2014-03-11T18:11:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8df3fd9ab9f107e78855bf52d48e1e99e5d931b3'/>
<id>8df3fd9ab9f107e78855bf52d48e1e99e5d931b3</id>
<content type='text'>
commit 596f3142d2b7be307a1652d59e7b93adab918437 upstream.

We always disable cr8 intercept in its handler, but only re-enable it
if handling KVM_REQ_EVENT, so there can be a window where we do not
intercept cr8 writes, which allows an interrupt to disrupt a higher
priority task.

Fix this by disabling intercepts in the same function that re-enables
them when needed. This fixes BSOD in Windows 2008.

Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Reviewed-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 596f3142d2b7be307a1652d59e7b93adab918437 upstream.

We always disable cr8 intercept in its handler, but only re-enable it
if handling KVM_REQ_EVENT, so there can be a window where we do not
intercept cr8 writes, which allows an interrupt to disrupt a higher
priority task.

Fix this by disabling intercepts in the same function that re-enables
them when needed. This fixes BSOD in Windows 2008.

Signed-off-by: Radim Krčmář &lt;rkrcmar@redhat.com&gt;
Reviewed-by: Marcelo Tosatti &lt;mtosatti@redhat.com&gt;
Signed-off-by: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>x86/amd/numa: Fix northbridge quirk to assign correct NUMA node</title>
<updated>2014-03-22T21:01:54+00:00</updated>
<author>
<name>Daniel J Blueman</name>
<email>daniel@numascale.com</email>
</author>
<published>2014-03-13T11:43:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e108610d6dcb947d4a8743f8f5bcfb008982826f'/>
<id>e108610d6dcb947d4a8743f8f5bcfb008982826f</id>
<content type='text'>
commit 847d7970defb45540735b3fb4e88471c27cacd85 upstream.

For systems with multiple servers and routed fabric, all
northbridges get assigned to the first server. Fix this by also
using the node reported from the PCI bus. For single-fabric
systems, the northbriges are on PCI bus 0 by definition, which
are on NUMA node 0 by definition, so this is invarient on most
systems.

Tested on fam10h and fam15h single and multi-fabric systems and
candidate for stable.

Signed-off-by: Daniel J Blueman &lt;daniel@numascale.com&gt;
Acked-by: Steffen Persvold &lt;sp@numascale.com&gt;
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394710981-3596-1-git-send-email-daniel@numascale.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 847d7970defb45540735b3fb4e88471c27cacd85 upstream.

For systems with multiple servers and routed fabric, all
northbridges get assigned to the first server. Fix this by also
using the node reported from the PCI bus. For single-fabric
systems, the northbriges are on PCI bus 0 by definition, which
are on NUMA node 0 by definition, so this is invarient on most
systems.

Tested on fam10h and fam15h single and multi-fabric systems and
candidate for stable.

Signed-off-by: Daniel J Blueman &lt;daniel@numascale.com&gt;
Acked-by: Steffen Persvold &lt;sp@numascale.com&gt;
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Link: http://lkml.kernel.org/r/1394710981-3596-1-git-send-email-daniel@numascale.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86: fix compile error due to X86_TRAP_NMI use in asm files</title>
<updated>2014-03-22T21:01:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2014-03-08T02:58:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=f4592be7d7d62c137999e058288618398fe2babc'/>
<id>f4592be7d7d62c137999e058288618398fe2babc</id>
<content type='text'>
commit b01d4e68933ec23e43b1046fa35d593cefcf37d1 upstream.

It's an enum, not a #define, you can't use it in asm files.

Introduced in commit 5fa10196bdb5 ("x86: Ignore NMIs that come in during
early boot"), and sadly I didn't compile-test things like I should have
before pushing out.

My weak excuse is that the x86 tree generally doesn't introduce stupid
things like this (and the ARM pull afterwards doesn't cause me to do a
compile-test either, since I don't cross-compile).

Cc: Don Zickus &lt;dzickus@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit b01d4e68933ec23e43b1046fa35d593cefcf37d1 upstream.

It's an enum, not a #define, you can't use it in asm files.

Introduced in commit 5fa10196bdb5 ("x86: Ignore NMIs that come in during
early boot"), and sadly I didn't compile-test things like I should have
before pushing out.

My weak excuse is that the x86 tree generally doesn't introduce stupid
things like this (and the ARM pull afterwards doesn't cause me to do a
compile-test either, since I don't cross-compile).

Cc: Don Zickus &lt;dzickus@redhat.com&gt;
Cc: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>x86: Ignore NMIs that come in during early boot</title>
<updated>2014-03-22T21:01:54+00:00</updated>
<author>
<name>H. Peter Anvin</name>
<email>hpa@linux.intel.com</email>
</author>
<published>2014-03-07T23:05:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8ee7e9f35c9327cedcefc28ce6ad4f30b20bc579'/>
<id>8ee7e9f35c9327cedcefc28ce6ad4f30b20bc579</id>
<content type='text'>
commit 5fa10196bdb5f190f595ebd048490ee52dddea0f upstream.

Don Zickus reports:

A customer generated an external NMI using their iLO to test kdump
worked.  Unfortunately, the machine hung.  Disabling the nmi_watchdog
made things work.

I speculated the external NMI fired, caused the machine to panic (as
expected) and the perf NMI from the watchdog came in and was latched.
My guess was this somehow caused the hang.

   ----

It appears that the latched NMI stays latched until the early page
table generation on 64 bits, which causes exceptions to happen which
end in IRET, which re-enable NMI.  Therefore, ignore NMIs that come in
during early execution, until we have proper exception handling.

Reported-and-tested-by: Don Zickus &lt;dzickus@redhat.com&gt;
Link: http://lkml.kernel.org/r/1394221143-29713-1-git-send-email-dzickus@redhat.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 5fa10196bdb5f190f595ebd048490ee52dddea0f upstream.

Don Zickus reports:

A customer generated an external NMI using their iLO to test kdump
worked.  Unfortunately, the machine hung.  Disabling the nmi_watchdog
made things work.

I speculated the external NMI fired, caused the machine to panic (as
expected) and the perf NMI from the watchdog came in and was latched.
My guess was this somehow caused the hang.

   ----

It appears that the latched NMI stays latched until the early page
table generation on 64 bits, which causes exceptions to happen which
end in IRET, which re-enable NMI.  Therefore, ignore NMIs that come in
during early execution, until we have proper exception handling.

Reported-and-tested-by: Don Zickus &lt;dzickus@redhat.com&gt;
Link: http://lkml.kernel.org/r/1394221143-29713-1-git-send-email-dzickus@redhat.com
Signed-off-by: H. Peter Anvin &lt;hpa@linux.intel.com&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7991/1: sa1100: fix compile problem on Collie</title>
<updated>2014-03-22T21:01:53+00:00</updated>
<author>
<name>Linus Walleij</name>
<email>linus.walleij@linaro.org</email>
</author>
<published>2014-02-25T21:41:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8afe392ee3e84c94ecb595e435dd54f864739bac'/>
<id>8afe392ee3e84c94ecb595e435dd54f864739bac</id>
<content type='text'>
commit 052450fdc55894a39fbae93d9bbe43947956f663 upstream.

Due to a problem in the MFD Kconfig it was not possible to
compile the UCB battery driver for the Collie SA1100 system,
in turn making it impossible to compile in the battery driver.
(See patch "mfd: include all drivers in subsystem menu".)

After fixing the MFD Kconfig (separate patch) a compile error
appears in the Collie battery driver due to the &lt;mach/collie.h&gt;
implicitly requiring &lt;mach/hardware.h&gt; through &lt;linux/gpio.h&gt;
via &lt;mach/gpio.h&gt; prior to commit
40ca061b "ARM: 7841/1: sa1100: remove complex GPIO interface".

Fix this up by including the required header into
&lt;mach/collie.h&gt;.

Cc: Andrea Adami &lt;andrea.adami@gmail.com&gt;
Cc: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Signed-off-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 052450fdc55894a39fbae93d9bbe43947956f663 upstream.

Due to a problem in the MFD Kconfig it was not possible to
compile the UCB battery driver for the Collie SA1100 system,
in turn making it impossible to compile in the battery driver.
(See patch "mfd: include all drivers in subsystem menu".)

After fixing the MFD Kconfig (separate patch) a compile error
appears in the Collie battery driver due to the &lt;mach/collie.h&gt;
implicitly requiring &lt;mach/hardware.h&gt; through &lt;linux/gpio.h&gt;
via &lt;mach/gpio.h&gt; prior to commit
40ca061b "ARM: 7841/1: sa1100: remove complex GPIO interface".

Fix this up by including the required header into
&lt;mach/collie.h&gt;.

Cc: Andrea Adami &lt;andrea.adami@gmail.com&gt;
Cc: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Signed-off-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc: Align p_dyn, p_rela and p_st symbols</title>
<updated>2014-03-22T21:01:53+00:00</updated>
<author>
<name>Anton Blanchard</name>
<email>anton@samba.org</email>
</author>
<published>2014-03-03T21:31:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=49799bba6fc2d0c3a32bf4c5c30b4d74ea689628'/>
<id>49799bba6fc2d0c3a32bf4c5c30b4d74ea689628</id>
<content type='text'>
commit a5b2cf5b1af424ee3dd9e3ce6d5cea18cb927e67 upstream.

The 64bit relocation code places a few symbols in the text segment.
These symbols are only 4 byte aligned where they need to be 8 byte
aligned. Add an explicit alignment.

Signed-off-by: Anton Blanchard &lt;anton@samba.org&gt;
Tested-by: Laurent Dufour &lt;ldufour@linux.vnet.ibm.com&gt;
Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit a5b2cf5b1af424ee3dd9e3ce6d5cea18cb927e67 upstream.

The 64bit relocation code places a few symbols in the text segment.
These symbols are only 4 byte aligned where they need to be 8 byte
aligned. Add an explicit alignment.

Signed-off-by: Anton Blanchard &lt;anton@samba.org&gt;
Tested-by: Laurent Dufour &lt;ldufour@linux.vnet.ibm.com&gt;
Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>powerpc/tm: Fix crash when forking inside a transaction</title>
<updated>2014-03-22T21:01:53+00:00</updated>
<author>
<name>Michael Neuling</name>
<email>mikey@neuling.org</email>
</author>
<published>2014-03-03T03:21:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2725f34b41f8e3f444688a814cc2763a1c2b138b'/>
<id>2725f34b41f8e3f444688a814cc2763a1c2b138b</id>
<content type='text'>
commit 621b5060e823301d0cba4cb52a7ee3491922d291 upstream.

When we fork/clone we currently don't copy any of the TM state to the new
thread.  This results in a TM bad thing (program check) when the new process is
switched in as the kernel does a tmrechkpt with TEXASR FS not set.  Also, since
R1 is from userspace, we trigger the bad kernel stack pointer detection.  So we
end up with something like this:

   Bad kernel stack pointer 0 at c0000000000404fc
   cpu 0x2: Vector: 700 (Program Check) at [c00000003ffefd40]
       pc: c0000000000404fc: restore_gprs+0xc0/0x148
       lr: 0000000000000000
       sp: 0
      msr: 9000000100201030
     current = 0xc000001dd1417c30
     paca    = 0xc00000000fe00800   softe: 0        irq_happened: 0x01
       pid   = 0, comm = swapper/2
   WARNING: exception is not recoverable, can't continue

The below fixes this by flushing the TM state before we copy the task_struct to
the clone.  To do this we go through the tmreclaim patch, which removes the
checkpointed registers from the CPU and transitions the CPU out of TM suspend
mode.  Hence we need to call tmrechkpt after to restore the checkpointed state
and the TM mode for the current task.

To make this fail from userspace is simply:
	tbegin
	li	r0, 2
	sc
	&lt;boom&gt;

Kudos to Adhemerval Zanella Neto for finding this.

Signed-off-by: Michael Neuling &lt;mikey@neuling.org&gt;
cc: Adhemerval Zanella Neto &lt;azanella@br.ibm.com&gt;
Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 621b5060e823301d0cba4cb52a7ee3491922d291 upstream.

When we fork/clone we currently don't copy any of the TM state to the new
thread.  This results in a TM bad thing (program check) when the new process is
switched in as the kernel does a tmrechkpt with TEXASR FS not set.  Also, since
R1 is from userspace, we trigger the bad kernel stack pointer detection.  So we
end up with something like this:

   Bad kernel stack pointer 0 at c0000000000404fc
   cpu 0x2: Vector: 700 (Program Check) at [c00000003ffefd40]
       pc: c0000000000404fc: restore_gprs+0xc0/0x148
       lr: 0000000000000000
       sp: 0
      msr: 9000000100201030
     current = 0xc000001dd1417c30
     paca    = 0xc00000000fe00800   softe: 0        irq_happened: 0x01
       pid   = 0, comm = swapper/2
   WARNING: exception is not recoverable, can't continue

The below fixes this by flushing the TM state before we copy the task_struct to
the clone.  To do this we go through the tmreclaim patch, which removes the
checkpointed registers from the CPU and transitions the CPU out of TM suspend
mode.  Hence we need to call tmrechkpt after to restore the checkpointed state
and the TM mode for the current task.

To make this fail from userspace is simply:
	tbegin
	li	r0, 2
	sc
	&lt;boom&gt;

Kudos to Adhemerval Zanella Neto for finding this.

Signed-off-by: Michael Neuling &lt;mikey@neuling.org&gt;
cc: Adhemerval Zanella Neto &lt;azanella@br.ibm.com&gt;
Signed-off-by: Benjamin Herrenschmidt &lt;benh@kernel.crashing.org&gt;
Signed-off-by: Jiri Slaby &lt;jslaby@suse.cz&gt;

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