<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/arch/arm, branch v3.4.76</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>ARM: OMAP2+: hwmod: Fix SOFTRESET logic</title>
<updated>2013-12-20T15:34:21+00:00</updated>
<author>
<name>Roger Quadros</name>
<email>rogerq@ti.com</email>
</author>
<published>2013-12-09T01:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2c64388e8bde7f654167ac2dca485e9545dd6915'/>
<id>2c64388e8bde7f654167ac2dca485e9545dd6915</id>
<content type='text'>
commit 313a76ee11cda6700548afe68499ef174a240688 upstream.

In _ocp_softreset(), after _set_softreset() + write_sysconfig(),
the hwmod's sysc_cache will always contain SOFTRESET bit set
so all further writes to sysconfig using this cache will initiate
a repeated SOFTRESET e.g. enable_sysc(). This is true for OMAP3 like
platforms that have RESET_DONE status in the SYSSTATUS register and
so the the SOFTRESET bit in SYSCONFIG is not automatically cleared.
It is not a problem for OMAP4 like platforms that indicate RESET
completion by clearing the SOFTRESET bit in the SYSCONFIG register.

This repeated SOFTRESET is undesired and was the root cause of
USB host issues on OMAP3 platforms when hwmod was allowed to do the
SOFTRESET for the USB Host module.

To fix this we clear the SOFTRESET bit and update the sysconfig
register + sysc_cache using write_sysconfig().

Signed-off-by: Roger Quadros &lt;rogerq@ti.com&gt;
Tested-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt; # Panda, BeagleXM
[paul@pwsan.com: renamed _clr_softreset() to _clear_softreset()]
Signed-off-by: Paul Walmsley &lt;paul@pwsan.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 313a76ee11cda6700548afe68499ef174a240688 upstream.

In _ocp_softreset(), after _set_softreset() + write_sysconfig(),
the hwmod's sysc_cache will always contain SOFTRESET bit set
so all further writes to sysconfig using this cache will initiate
a repeated SOFTRESET e.g. enable_sysc(). This is true for OMAP3 like
platforms that have RESET_DONE status in the SYSSTATUS register and
so the the SOFTRESET bit in SYSCONFIG is not automatically cleared.
It is not a problem for OMAP4 like platforms that indicate RESET
completion by clearing the SOFTRESET bit in the SYSCONFIG register.

This repeated SOFTRESET is undesired and was the root cause of
USB host issues on OMAP3 platforms when hwmod was allowed to do the
SOFTRESET for the USB Host module.

To fix this we clear the SOFTRESET bit and update the sysconfig
register + sysc_cache using write_sysconfig().

Signed-off-by: Roger Quadros &lt;rogerq@ti.com&gt;
Tested-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt; # Panda, BeagleXM
[paul@pwsan.com: renamed _clr_softreset() to _clear_softreset()]
Signed-off-by: Paul Walmsley &lt;paul@pwsan.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7913/1: fix framepointer check in unwind_frame</title>
<updated>2013-12-20T15:34:19+00:00</updated>
<author>
<name>Konstantin Khlebnikov</name>
<email>k.khlebnikov@samsung.com</email>
</author>
<published>2013-12-05T13:23:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=47131c7c78b82c3b67020ee99834841ec6f096b5'/>
<id>47131c7c78b82c3b67020ee99834841ec6f096b5</id>
<content type='text'>
commit 3abb6671a9c04479c4bd026798a05f857393b7e2 upstream.

This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -&gt; fp + 4 == 3.

Signed-off-by: Konstantin Khlebnikov &lt;k.khlebnikov@samsung.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&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 3abb6671a9c04479c4bd026798a05f857393b7e2 upstream.

This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -&gt; fp + 4 == 3.

Signed-off-by: Konstantin Khlebnikov &lt;k.khlebnikov@samsung.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7912/1: check stack pointer in get_wchan</title>
<updated>2013-12-20T15:34:19+00:00</updated>
<author>
<name>Konstantin Khlebnikov</name>
<email>k.khlebnikov@samsung.com</email>
</author>
<published>2013-12-05T13:21:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=fa2ea62aebfc642b13e0bd02c693c35cc910605c'/>
<id>fa2ea62aebfc642b13e0bd02c693c35cc910605c</id>
<content type='text'>
commit 1b15ec7a7427d4188ba91b9bbac696250a059d22 upstream.

get_wchan() is lockless. Task may wakeup at any time and change its own stack,
thus each next stack frame may be overwritten and filled with random stuff.

/proc/$pid/stack interface had been disabled for non-current tasks, see [1]
But 'wchan' still allows to trigger stack frame unwinding on volatile stack.

This patch fixes oops in unwind_frame() by adding stack pointer validation on
each step (as x86 code do), unwind_frame() already checks frame pointer.

Also I've found another report of this oops on stackoverflow (irony).

Link: http://www.spinics.net/lists/arm-kernel/msg110589.html [1]
Link: http://stackoverflow.com/questions/18479894/unwind-frame-cause-a-kernel-paging-error

Signed-off-by: Konstantin Khlebnikov &lt;k.khlebnikov@samsung.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&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 1b15ec7a7427d4188ba91b9bbac696250a059d22 upstream.

get_wchan() is lockless. Task may wakeup at any time and change its own stack,
thus each next stack frame may be overwritten and filled with random stuff.

/proc/$pid/stack interface had been disabled for non-current tasks, see [1]
But 'wchan' still allows to trigger stack frame unwinding on volatile stack.

This patch fixes oops in unwind_frame() by adding stack pointer validation on
each step (as x86 code do), unwind_frame() already checks frame pointer.

Also I've found another report of this oops on stackoverflow (irony).

Link: http://www.spinics.net/lists/arm-kernel/msg110589.html [1]
Link: http://stackoverflow.com/questions/18479894/unwind-frame-cause-a-kernel-paging-error

Signed-off-by: Konstantin Khlebnikov &lt;k.khlebnikov@samsung.com&gt;
Acked-by: Will Deacon &lt;will.deacon@arm.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: OMAP3: hwmod data: Don't prevent RESET of USB Host module</title>
<updated>2013-12-20T15:34:19+00:00</updated>
<author>
<name>Roger Quadros</name>
<email>rogerq@ti.com</email>
</author>
<published>2013-12-09T01:39:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=c68cc16363bf6d92d8c7e017becec8bfb76f040b'/>
<id>c68cc16363bf6d92d8c7e017becec8bfb76f040b</id>
<content type='text'>
commit 7f4d3641e2548d1ac5dee837ff434df668a2810c upstream.

Unlike what the comment states, errata i660 does not state that we
can't RESET the USB host module. Instead it states that RESET is the
only way to recover from a deadlock situation.

RESET ensures that the module is in a known good state irrespective
of what bootloader does with the module, so it must be done at boot.

Signed-off-by: Roger Quadros &lt;rogerq@ti.com&gt;
Tested-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt; # Panda, BeagleXM
Fixes: de231388cb80 ("ARM: OMAP: USB: EHCI and OHCI hwmod structures for OMAP3")
Signed-off-by: Paul Walmsley &lt;paul@pwsan.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 7f4d3641e2548d1ac5dee837ff434df668a2810c upstream.

Unlike what the comment states, errata i660 does not state that we
can't RESET the USB host module. Instead it states that RESET is the
only way to recover from a deadlock situation.

RESET ensures that the module is in a known good state irrespective
of what bootloader does with the module, so it must be done at boot.

Signed-off-by: Roger Quadros &lt;rogerq@ti.com&gt;
Tested-by: Tomi Valkeinen &lt;tomi.valkeinen@ti.com&gt; # Panda, BeagleXM
Fixes: de231388cb80 ("ARM: OMAP: USB: EHCI and OHCI hwmod structures for OMAP3")
Signed-off-by: Paul Walmsley &lt;paul@pwsan.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: pxa: tosa: fix keys mapping</title>
<updated>2013-12-20T15:34:19+00:00</updated>
<author>
<name>Dmitry Eremin-Solenikov</name>
<email>dbaryshkov@gmail.com</email>
</author>
<published>2013-11-16T12:47:50+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=921f3429bb9c9e3f20592c740ee356de9702e2ba'/>
<id>921f3429bb9c9e3f20592c740ee356de9702e2ba</id>
<content type='text'>
commit 506cac15ac86f204b83e3cfccde73eeb4e7c5f34 upstream.

When converting from tosa-keyboard driver to matrix keyboard, tosa keys
received extra 1 column shift. Replace that with correct values to make
keyboard work again.

Fixes: f69a6548c9d5 ('[ARM] pxa/tosa: make use of the matrix keypad driver')
Signed-off-by: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Signed-off-by: Haojian Zhuang &lt;haojian.zhuang@gmail.com&gt;
Signed-off-by: Olof Johansson &lt;olof@lixom.net&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 506cac15ac86f204b83e3cfccde73eeb4e7c5f34 upstream.

When converting from tosa-keyboard driver to matrix keyboard, tosa keys
received extra 1 column shift. Replace that with correct values to make
keyboard work again.

Fixes: f69a6548c9d5 ('[ARM] pxa/tosa: make use of the matrix keypad driver')
Signed-off-by: Dmitry Eremin-Solenikov &lt;dbaryshkov@gmail.com&gt;
Signed-off-by: Haojian Zhuang &lt;haojian.zhuang@gmail.com&gt;
Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: integrator_cp: Set LCD{0,1} enable lines when turning on CLCD</title>
<updated>2013-12-04T18:50:13+00:00</updated>
<author>
<name>Jonathan Austin</name>
<email>jonathan.austin@arm.com</email>
</author>
<published>2013-08-29T17:41:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b823b82878ad6c8d938bb99fb3ed3f6c75b0f323'/>
<id>b823b82878ad6c8d938bb99fb3ed3f6c75b0f323</id>
<content type='text'>
commit 30aeadd44deea3f3b0df45b9a70ee0fd5f8d6dc2 upstream.

This turns on the internal integrator LCD display(s). It seems that the code
to do this got lost in refactoring of the CLCD driver.

Signed-off-by: Jonathan Austin &lt;jonathan.austin@arm.com&gt;
Acked-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Olof Johansson &lt;olof@lixom.net&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 30aeadd44deea3f3b0df45b9a70ee0fd5f8d6dc2 upstream.

This turns on the internal integrator LCD display(s). It seems that the code
to do this got lost in refactoring of the CLCD driver.

Signed-off-by: Jonathan Austin &lt;jonathan.austin@arm.com&gt;
Acked-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Olof Johansson &lt;olof@lixom.net&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: sa11x0/assabet: ensure CS2 is configured appropriately</title>
<updated>2013-12-04T18:50:13+00:00</updated>
<author>
<name>Russell King</name>
<email>rmk+kernel@arm.linux.org.uk</email>
</author>
<published>2013-10-15T23:09:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d88da9d09672eddc30d50dec14cd8ddc3fbc284c'/>
<id>d88da9d09672eddc30d50dec14cd8ddc3fbc284c</id>
<content type='text'>
commit f3964fe1c9d9a887d65faf594669852e4dec46e0 upstream.

The CS2 region contains the Assabet board configuration and status
registers, which are 32-bit.  Unfortunately, some boot loaders do not
configure this region correctly, leaving it setup as a 16-bit region.
Fix this.

Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&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 f3964fe1c9d9a887d65faf594669852e4dec46e0 upstream.

The CS2 region contains the Assabet board configuration and status
registers, which are 32-bit.  Unfortunately, some boot loaders do not
configure this region correctly, leaving it setup as a 16-bit region.
Fix this.

Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7670/1: fix the memset fix</title>
<updated>2013-11-20T18:43:19+00:00</updated>
<author>
<name>Nicolas Pitre</name>
<email>nicolas.pitre@linaro.org</email>
</author>
<published>2013-03-12T12:00:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d1814ea12da067fda7bac933e06ef205163617f6'/>
<id>d1814ea12da067fda7bac933e06ef205163617f6</id>
<content type='text'>
commit 418df63adac56841ef6b0f1fcf435bc64d4ed177 upstream.

Commit 455bd4c430b0 ("ARM: 7668/1: fix memset-related crashes caused by
recent GCC (4.7.2) optimizations") attempted to fix a compliance issue
with the memset return value.  However the memset itself became broken
by that patch for misaligned pointers.

This fixes the above by branching over the entry code from the
misaligned fixup code to avoid reloading the original pointer.

Also, because the function entry alignment is wrong in the Thumb mode
compilation, that fixup code is moved to the end.

While at it, the entry instructions are slightly reworked to help dual
issue pipelines.

Signed-off-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Tested-by: Alexander Holler &lt;holler@ahsoftware.de&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Eric Bénard &lt;eric@eukrea.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 418df63adac56841ef6b0f1fcf435bc64d4ed177 upstream.

Commit 455bd4c430b0 ("ARM: 7668/1: fix memset-related crashes caused by
recent GCC (4.7.2) optimizations") attempted to fix a compliance issue
with the memset return value.  However the memset itself became broken
by that patch for misaligned pointers.

This fixes the above by branching over the entry code from the
misaligned fixup code to avoid reloading the original pointer.

Also, because the function entry alignment is wrong in the Thumb mode
compilation, that fixup code is moved to the end.

While at it, the entry instructions are slightly reworked to help dual
issue pipelines.

Signed-off-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Tested-by: Alexander Holler &lt;holler@ahsoftware.de&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Eric Bénard &lt;eric@eukrea.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>ARM: 7668/1: fix memset-related crashes caused by recent GCC (4.7.2) optimizations</title>
<updated>2013-11-20T18:43:19+00:00</updated>
<author>
<name>Ivan Djelic</name>
<email>ivan.djelic@parrot.com</email>
</author>
<published>2013-03-06T19:09:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e6fffec6636ffa3062891bae69a3895bbb73b148'/>
<id>e6fffec6636ffa3062891bae69a3895bbb73b148</id>
<content type='text'>
commit 455bd4c430b0c0a361f38e8658a0d6cb469942b5 upstream.

Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on
assumptions about the implementation of memset and similar functions.
The current ARM optimized memset code does not return the value of
its first argument, as is usually expected from standard implementations.

For instance in the following function:

void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
{
	memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
	waiter-&gt;magic = waiter;
	INIT_LIST_HEAD(&amp;waiter-&gt;list);
}

compiled as:

800554d0 &lt;debug_mutex_lock_common&gt;:
800554d0:       e92d4008        push    {r3, lr}
800554d4:       e1a00001        mov     r0, r1
800554d8:       e3a02010        mov     r2, #16 ; 0x10
800554dc:       e3a01011        mov     r1, #17 ; 0x11
800554e0:       eb04426e        bl      80165ea0 &lt;memset&gt;
800554e4:       e1a03000        mov     r3, r0
800554e8:       e583000c        str     r0, [r3, #12]
800554ec:       e5830000        str     r0, [r3]
800554f0:       e5830004        str     r0, [r3, #4]
800554f4:       e8bd8008        pop     {r3, pc}

GCC assumes memset returns the value of pointer 'waiter' in register r0; causing
register/memory corruptions.

This patch fixes the return value of the assembly version of memset.
It adds a 'mov' instruction and merges an additional load+store into
existing load/store instructions.
For ease of review, here is a breakdown of the patch into 4 simple steps:

Step 1
======
Perform the following substitutions:
ip -&gt; r8, then
r0 -&gt; ip,
and insert 'mov ip, r0' as the first statement of the function.
At this point, we have a memset() implementation returning the proper result,
but corrupting r8 on some paths (the ones that were using ip).

Step 2
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 1:

save r8:
-       str     lr, [sp, #-4]!
+       stmfd   sp!, {r8, lr}

and restore r8 on both exit paths:
-       ldmeqfd sp!, {pc}               @ Now &lt;64 bytes to go.
+       ldmeqfd sp!, {r8, pc}           @ Now &lt;64 bytes to go.
(...)
        tst     r2, #16
        stmneia ip!, {r1, r3, r8, lr}
-       ldr     lr, [sp], #4
+       ldmfd   sp!, {r8, lr}

Step 3
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 0:

save r8:
-       stmfd   sp!, {r4-r7, lr}
+       stmfd   sp!, {r4-r8, lr}

and restore r8 on both exit paths:
        bgt     3b
-       ldmeqfd sp!, {r4-r7, pc}
+       ldmeqfd sp!, {r4-r8, pc}
(...)
        tst     r2, #16
        stmneia ip!, {r4-r7}
-       ldmfd   sp!, {r4-r7, lr}
+       ldmfd   sp!, {r4-r8, lr}

Step 4
======
Rewrite register list "r4-r7, r8" as "r4-r8".

Signed-off-by: Ivan Djelic &lt;ivan.djelic@parrot.com&gt;
Reviewed-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Dirk Behme &lt;dirk.behme@gmail.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Eric Bénard &lt;eric@eukrea.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 455bd4c430b0c0a361f38e8658a0d6cb469942b5 upstream.

Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on
assumptions about the implementation of memset and similar functions.
The current ARM optimized memset code does not return the value of
its first argument, as is usually expected from standard implementations.

For instance in the following function:

void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter)
{
	memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter));
	waiter-&gt;magic = waiter;
	INIT_LIST_HEAD(&amp;waiter-&gt;list);
}

compiled as:

800554d0 &lt;debug_mutex_lock_common&gt;:
800554d0:       e92d4008        push    {r3, lr}
800554d4:       e1a00001        mov     r0, r1
800554d8:       e3a02010        mov     r2, #16 ; 0x10
800554dc:       e3a01011        mov     r1, #17 ; 0x11
800554e0:       eb04426e        bl      80165ea0 &lt;memset&gt;
800554e4:       e1a03000        mov     r3, r0
800554e8:       e583000c        str     r0, [r3, #12]
800554ec:       e5830000        str     r0, [r3]
800554f0:       e5830004        str     r0, [r3, #4]
800554f4:       e8bd8008        pop     {r3, pc}

GCC assumes memset returns the value of pointer 'waiter' in register r0; causing
register/memory corruptions.

This patch fixes the return value of the assembly version of memset.
It adds a 'mov' instruction and merges an additional load+store into
existing load/store instructions.
For ease of review, here is a breakdown of the patch into 4 simple steps:

Step 1
======
Perform the following substitutions:
ip -&gt; r8, then
r0 -&gt; ip,
and insert 'mov ip, r0' as the first statement of the function.
At this point, we have a memset() implementation returning the proper result,
but corrupting r8 on some paths (the ones that were using ip).

Step 2
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 1:

save r8:
-       str     lr, [sp, #-4]!
+       stmfd   sp!, {r8, lr}

and restore r8 on both exit paths:
-       ldmeqfd sp!, {pc}               @ Now &lt;64 bytes to go.
+       ldmeqfd sp!, {r8, pc}           @ Now &lt;64 bytes to go.
(...)
        tst     r2, #16
        stmneia ip!, {r1, r3, r8, lr}
-       ldr     lr, [sp], #4
+       ldmfd   sp!, {r8, lr}

Step 3
======
Make sure r8 is saved and restored when (! CALGN(1)+0) == 0:

save r8:
-       stmfd   sp!, {r4-r7, lr}
+       stmfd   sp!, {r4-r8, lr}

and restore r8 on both exit paths:
        bgt     3b
-       ldmeqfd sp!, {r4-r7, pc}
+       ldmeqfd sp!, {r4-r8, pc}
(...)
        tst     r2, #16
        stmneia ip!, {r4-r7}
-       ldmfd   sp!, {r4-r7, lr}
+       ldmfd   sp!, {r4-r8, lr}

Step 4
======
Rewrite register list "r4-r7, r8" as "r4-r8".

Signed-off-by: Ivan Djelic &lt;ivan.djelic@parrot.com&gt;
Reviewed-by: Nicolas Pitre &lt;nico@linaro.org&gt;
Signed-off-by: Dirk Behme &lt;dirk.behme@gmail.com&gt;
Signed-off-by: Russell King &lt;rmk+kernel@arm.linux.org.uk&gt;
Cc: Eric Bénard &lt;eric@eukrea.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>mm, show_mem: suppress page counts in non-blockable contexts</title>
<updated>2013-10-13T22:42:49+00:00</updated>
<author>
<name>David Rientjes</name>
<email>rientjes@google.com</email>
</author>
<published>2013-04-29T22:06:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=022a41db8aa1bc0b4ff4c013f889292324a1c465'/>
<id>022a41db8aa1bc0b4ff4c013f889292324a1c465</id>
<content type='text'>
commit 4b59e6c4730978679b414a8da61514a2518da512 upstream.

On large systems with a lot of memory, walking all RAM to determine page
types may take a half second or even more.

In non-blockable contexts, the page allocator will emit a page allocation
failure warning unless __GFP_NOWARN is specified.  In such contexts, irqs
are typically disabled and such a lengthy delay may even result in NMI
watchdog timeouts.

To fix this, suppress the page walk in such contexts when printing the
page allocation failure warning.

Signed-off-by: David Rientjes &lt;rientjes@google.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Dave Hansen &lt;dave@linux.vnet.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Xishi Qiu &lt;qiuxishi@huawei.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 4b59e6c4730978679b414a8da61514a2518da512 upstream.

On large systems with a lot of memory, walking all RAM to determine page
types may take a half second or even more.

In non-blockable contexts, the page allocator will emit a page allocation
failure warning unless __GFP_NOWARN is specified.  In such contexts, irqs
are typically disabled and such a lengthy delay may even result in NMI
watchdog timeouts.

To fix this, suppress the page walk in such contexts when printing the
page allocation failure warning.

Signed-off-by: David Rientjes &lt;rientjes@google.com&gt;
Cc: Mel Gorman &lt;mgorman@suse.de&gt;
Acked-by: Michal Hocko &lt;mhocko@suse.cz&gt;
Cc: Dave Hansen &lt;dave@linux.vnet.ibm.com&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Xishi Qiu &lt;qiuxishi@huawei.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

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