linux-toradex.git/arch, branch v2.6.36.2 Linux kernel for Apalis and Colibri modules nmi: fix clock comparator revalidation 2010-12-09T21:33:35+00:00 Heiko Carstens heiko.carstens@de.ibm.com 2010-11-25T08:52:45+00:00 3975673309f769b52c961b3c31df0d78b05fa9a3 commit e8129c642155616d9e2160a75f103e127c8c3708 upstream. On each machine check all registers are revalidated. The save area for the clock comparator however only contains the upper most seven bytes of the former contents, if valid. Therefore the machine check handler uses a store clock instruction to get the current time and writes that to the clock comparator register which in turn will generate an immediate timer interrupt. However within the lowcore the expected time of the next timer interrupt is stored. If the interrupt happens before that time the handler won't be called. In turn the clock comparator won't be reprogrammed and therefore the interrupt condition stays pending which causes an interrupt loop until the expected time is reached. On NOHZ machines this can result in unresponsive machines since the time of the next expected interrupted can be a couple of days in the future. To fix this just revalidate the clock comparator register with the expected value. In addition the special handling for udelay must be changed as well. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit e8129c642155616d9e2160a75f103e127c8c3708 upstream.

On each machine check all registers are revalidated. The save area for
the clock comparator however only contains the upper most seven bytes
of the former contents, if valid.
Therefore the machine check handler uses a store clock instruction to
get the current time and writes that to the clock comparator register
which in turn will generate an immediate timer interrupt.
However within the lowcore the expected time of the next timer
interrupt is stored. If the interrupt happens before that time the
handler won't be called. In turn the clock comparator won't be
reprogrammed and therefore the interrupt condition stays pending which
causes an interrupt loop until the expected time is reached.

On NOHZ machines this can result in unresponsive machines since the
time of the next expected interrupted can be a couple of days in the
future.

To fix this just revalidate the clock comparator register with the
expected value.
In addition the special handling for udelay must be changed as well.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
OMAP3: DMA: Errata i541: sDMA FIFO draining does not finish 2010-12-09T21:33:29+00:00 Peter Ujfalusi peter.ujfalusi@nokia.com 2010-10-11T21:18:56+00:00 3908f08f0c5a6f67ee7c7cf2e816d01a5cf2d259 commit 0e4905c0199d683497833be60a428c784d7575b8 upstream. Implement the suggested workaround for OMAP3 regarding to sDMA draining issue, when the channel is disabled on the fly. This errata affects the following configuration: sDMA transfer is source synchronized Buffering is enabled SmartStandby is selected. The issue can be easily reproduced by creating overrun situation while recording audio. Either introduce load to the CPU: nice -19 arecord -D hw:0 -M -B 10000 -F 5000 -f dat > /dev/null & \ dd if=/dev/urandom of=/dev/null or suspending the arecord, and resuming it: arecord -D hw:0 -M -B 10000 -F 5000 -f dat > /dev/null CTRL+Z; fg; CTRL+Z; fg; ... In case of overrun audio stops DMA, and restarts it (without reseting the sDMA channel). When we hit this errata in stop case (sDMA drain did not complete), at the coming start the sDMA will not going to be operational (it is still draining). This leads to DMA stall condition. On OMAP3 we can recover with sDMA channel reset, it has been observed that by introducing unrelated sDMA activity might also help (reading from MMC for example). The same errata exists for OMAP2, where the suggestion is to disable the buffering to avoid this type of error. On OMAP3 the suggestion is to set sDMA to NoStandby before disabling the channel, and wait for the drain to finish, than configure sDMA to SmartStandby again. Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com> Acked-by: Jarkko Nikula <jhnikula@gmail.com> Acked-by : Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by : Manjunath Kondaiah G <manjugk@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 0e4905c0199d683497833be60a428c784d7575b8 upstream.

Implement the suggested workaround for OMAP3 regarding to sDMA draining
issue, when the channel is disabled on the fly.
This errata affects the following configuration:
sDMA transfer is source synchronized
Buffering is enabled
SmartStandby is selected.

The issue can be easily reproduced by creating overrun situation while
recording audio.
Either introduce load to the CPU:
nice -19 arecord -D hw:0 -M -B 10000 -F 5000 -f dat > /dev/null & \
dd if=/dev/urandom of=/dev/null

or suspending the arecord, and resuming it:
arecord -D hw:0 -M -B 10000 -F 5000 -f dat > /dev/null
CTRL+Z; fg; CTRL+Z; fg; ...

In case of overrun audio stops DMA, and restarts it (without reseting
the sDMA channel). When we hit this errata in stop case (sDMA drain did
not complete), at the coming start the sDMA will not going to be
operational (it is still draining).
This leads to DMA stall condition.
On OMAP3 we can recover with sDMA channel reset, it has been observed
that by introducing unrelated sDMA activity might also help (reading
from MMC for example).

The same errata exists for OMAP2, where the suggestion is to disable the
buffering to avoid this type of error.
On OMAP3 the suggestion is to set sDMA to NoStandby before disabling
the channel, and wait for the drain to finish, than configure sDMA to
SmartStandby again.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Jarkko Nikula <jhnikula@gmail.com>
Acked-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by : Manjunath Kondaiah G <manjugk@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
omap: dma: Fix buffering disable bit setting for omap24xx 2010-12-09T21:33:28+00:00 Jarkko Nikula jhnikula@gmail.com 2010-10-11T21:18:45+00:00 52ec3425c2f4e78db7c1ea864d64da4f6125779c commit 3e57f1626b5febe5cc99aa6870377deef3ae03cc upstream. An errata workaround for omap24xx is not setting the buffering disable bit 25 what is the purpose but channel enable bit 7 instead. Background for this fix is the DMA stalling issue with ASoC omap-mcbsp driver. Peter Ujfalusi <peter.ujfalusi@nokia.com> has found an issue in recording that the DMA stall could happen if there were a buffer overrun detected by ALSA and the DMA was stopped and restarted due that. This problem is known to occur on both OMAP2420 and OMAP3. It can recover on OMAP3 after dma free, dma request and reconfiguration cycle. However, on OMAP2420 it seems that only way to recover is a reset. Problem was not visible before the commit c12abc0. That commit changed that the McBSP transmitter/receiver is released from reset only when needed. That is, only enabled McBSP transmitter without transmission was able to prevent this DMA stall problem in receiving side and underlying problem did not show up until now. McBSP transmitter itself seems to no be reason since DMA stall does not recover by enabling the transmission after stall. Debugging showed that there were a DMA write active during DMA stop time and it never completed even when restarting the DMA. Experimenting showed that the DMA buffering disable bit could be used to avoid stalling when using source synchronized transfers. However that could have performance hit and OMAP3 TRM states that buffering disable is not allowed for destination synchronized transfers so subsequent patch will implement a method to complete DMA writes when stopping. This patch is based on assumtion that complete lock-up on OMAP2420 is different but related problem. I don't have access to OMAP2420 errata but I believe this old workaround here is put for a reason but unfortunately a wrong bit was typed and problem showed up only now. Signed-off-by: Jarkko Nikula <jhnikula@gmail.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com> Acked-by: Manjunath Kondaiah G <manjugk@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 3e57f1626b5febe5cc99aa6870377deef3ae03cc upstream.

An errata workaround for omap24xx is not setting the buffering disable bit
25 what is the purpose but channel enable bit 7 instead.

Background for this fix is the DMA stalling issue with ASoC omap-mcbsp
driver. Peter Ujfalusi <peter.ujfalusi@nokia.com> has found an issue in
recording that the DMA stall could happen if there were a buffer overrun
detected by ALSA and the DMA was stopped and restarted due that. This
problem is known to occur on both OMAP2420 and OMAP3. It can recover on
OMAP3 after dma free, dma request and reconfiguration cycle. However, on
OMAP2420 it seems that only way to recover is a reset.

Problem was not visible before the commit c12abc0. That commit changed that
the McBSP transmitter/receiver is released from reset only when needed. That
is, only enabled McBSP transmitter without transmission was able to prevent
this DMA stall problem in receiving side and underlying problem did not show
up until now. McBSP transmitter itself seems to no be reason since DMA
stall does not recover by enabling the transmission after stall.

Debugging showed that there were a DMA write active during DMA stop time and
it never completed even when restarting the DMA. Experimenting showed that
the DMA buffering disable bit could be used to avoid stalling when using
source synchronized transfers. However that could have performance hit and
OMAP3 TRM states that buffering disable is not allowed for destination
synchronized transfers so subsequent patch will implement a method to
complete DMA writes when stopping.

This patch is based on assumtion that complete lock-up on OMAP2420 is
different but related problem. I don't have access to OMAP2420 errata but
I believe this old workaround here is put for a reason but unfortunately
a wrong bit was typed and problem showed up only now.

Signed-off-by: Jarkko Nikula <jhnikula@gmail.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Manjunath Kondaiah G <manjugk@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
nohz/s390: fix arch_needs_cpu() return value on offline cpus 2010-12-09T21:33:27+00:00 Heiko Carstens heiko.carstens@de.ibm.com 2010-12-01T09:08:01+00:00 29f0ddcd392c16a47b7b8b335dc58c3642157460 commit 398812159e328478ae49b4bd01f0d71efea96c39 upstream. This fixes the same problem as described in the patch "nohz: fix printk_needs_cpu() return value on offline cpus" for the arch_needs_cpu() primitive: arch_needs_cpu() may return 1 if called on offline cpus. When a cpu gets offlined it schedules the idle process which, before killing its own cpu, will call tick_nohz_stop_sched_tick(). That function in turn will call arch_needs_cpu() in order to check if the local tick can be disabled. On offline cpus this function should naturally return 0 since regardless if the tick gets disabled or not the cpu will be dead short after. That is besides the fact that __cpu_disable() should already have made sure that no interrupts on the offlined cpu will be delivered anyway. In this case it prevents tick_nohz_stop_sched_tick() to call select_nohz_load_balancer(). No idea if that really is a problem. However what made me debug this is that on 2.6.32 the function get_nohz_load_balancer() is used within __mod_timer() to select a cpu on which a timer gets enqueued. If arch_needs_cpu() returns 1 then the nohz_load_balancer cpu doesn't get updated when a cpu gets offlined. It may contain the cpu number of an offline cpu. In turn timers get enqueued on an offline cpu and not very surprisingly they never expire and cause system hangs. This has been observed 2.6.32 kernels. On current kernels __mod_timer() uses get_nohz_timer_target() which doesn't have that problem. However there might be other problems because of the too early exit tick_nohz_stop_sched_tick() in case a cpu goes offline. This specific bug was indrocuded with 3c5d92a0 "nohz: Introduce arch_needs_cpu". In this case a cpu hotplug notifier is used to fix the issue in order to keep the normal/fast path small. All we need to do is to clear the condition that makes arch_needs_cpu() return 1 since it is just a performance improvement which is supposed to keep the local tick running for a short period if a cpu goes idle. Nothing special needs to be done except for clearing the condition. Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 398812159e328478ae49b4bd01f0d71efea96c39 upstream.

This fixes the same problem as described in the patch "nohz: fix
printk_needs_cpu() return value on offline cpus" for the arch_needs_cpu()
primitive:

arch_needs_cpu() may return 1 if called on offline cpus. When a cpu gets
offlined it schedules the idle process which, before killing its own cpu,
will call tick_nohz_stop_sched_tick().
That function in turn will call arch_needs_cpu() in order to check if the
local tick can be disabled. On offline cpus this function should naturally
return 0 since regardless if the tick gets disabled or not the cpu will be
dead short after. That is besides the fact that __cpu_disable() should already
have made sure that no interrupts on the offlined cpu will be delivered anyway.

In this case it prevents tick_nohz_stop_sched_tick() to call
select_nohz_load_balancer(). No idea if that really is a problem. However what
made me debug this is that on 2.6.32 the function get_nohz_load_balancer() is
used within __mod_timer() to select a cpu on which a timer gets enqueued.
If arch_needs_cpu() returns 1 then the nohz_load_balancer cpu doesn't get
updated when a cpu gets offlined. It may contain the cpu number of an offline
cpu. In turn timers get enqueued on an offline cpu and not very surprisingly
they never expire and cause system hangs.

This has been observed 2.6.32 kernels. On current kernels __mod_timer() uses
get_nohz_timer_target() which doesn't have that problem. However there might
be other problems because of the too early exit tick_nohz_stop_sched_tick()
in case a cpu goes offline.

This specific bug was indrocuded with 3c5d92a0 "nohz: Introduce
arch_needs_cpu".

In this case a cpu hotplug notifier is used to fix the issue in order to keep
the normal/fast path small. All we need to do is to clear the condition that
makes arch_needs_cpu() return 1 since it is just a performance improvement
which is supposed to keep the local tick running for a short period if a cpu
goes idle. Nothing special needs to be done except for clearing the condition.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ARM: cns3xxx: Fix build with CONFIG_PCI=y 2010-12-09T21:33:25+00:00 Anton Vorontsov cbouatmailru@gmail.com 2010-11-29T15:46:22+00:00 501bfbaead86ff24340ebddd5da338ec0562c969 commit 44266416f786514ec43a0d15ad951c34566b99c9 upstream. commit 6338a6aa7c082f11d55712251e14178c68bf5869 ("ARM: 6269/1: Add 'code' parameter for hook_fault_code()") breaks CNS3xxx build: CC arch/arm/mach-cns3xxx/pcie.o pcie.c: In function 'cns3xxx_pcie_init': pcie.c:373: warning: passing argument 4 of 'hook_fault_code' makes integer from pointer without a cast pcie.c:373: error: too few arguments to function 'hook_fault_code' This commit fixes the small issue. Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 44266416f786514ec43a0d15ad951c34566b99c9 upstream.

commit 6338a6aa7c082f11d55712251e14178c68bf5869 ("ARM: 6269/1: Add 'code'
parameter for hook_fault_code()") breaks CNS3xxx build:

  CC      arch/arm/mach-cns3xxx/pcie.o
pcie.c: In function 'cns3xxx_pcie_init':
pcie.c:373: warning: passing argument 4 of 'hook_fault_code' makes integer from pointer without a cast
pcie.c:373: error: too few arguments to function 'hook_fault_code'

This commit fixes the small issue.

Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ARM: 6482/2: Fix find_next_zero_bit and related assembly 2010-12-09T21:33:21+00:00 James Jones jajones@nvidia.com 2010-11-23T23:21:37+00:00 5dc21210d51aaf6db74c91c31b4e4f4f57a7691d commit 0e91ec0c06d2cd15071a6021c94840a50e6671aa upstream. The find_next_bit, find_first_bit, find_next_zero_bit and find_first_zero_bit functions were not properly clamping to the maxbit argument at the bit level. They were instead only checking maxbit at the byte level. To fix this, add a compare and a conditional move instruction to the end of the common bit-within-the- byte code used by all the functions and be sure not to clobber the maxbit argument before it is used. Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Tested-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: James Jones <jajones@nvidia.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 0e91ec0c06d2cd15071a6021c94840a50e6671aa upstream.

The find_next_bit, find_first_bit, find_next_zero_bit
and find_first_zero_bit functions were not properly
clamping to the maxbit argument at the bit level. They
were instead only checking maxbit at the byte level.
To fix this, add a compare and a conditional move
instruction to the end of the common bit-within-the-
byte code used by all the functions and be sure not to
clobber the maxbit argument before it is used.

Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: James Jones <jajones@nvidia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ARM: 6489/1: thumb2: fix incorrect optimisation in usracc 2010-12-09T21:33:20+00:00 Will Deacon will.deacon@arm.com 2010-11-19T12:18:31+00:00 5874ddc22780add4b0dd70db76989cc1ab4f3714 commit 1142b71d85894dcff1466dd6c871ea3c89e0352c upstream. Commit 8b592783 added a Thumb-2 variant of usracc which, when it is called with \rept=2, calls usraccoff once with an offset of 0 and secondly with a hard-coded offset of 4 in order to avoid incrementing the pointer again. If \inc != 4 then we will store the data to the wrong offset from \ptr. Luckily, the only caller that passes \rept=2 to this function is __clear_user so we haven't been actively corrupting user data. This patch fixes usracc to pass \inc instead of #4 to usraccoff when it is called a second time. Reported-by: Tony Thompson <tony.thompson@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 1142b71d85894dcff1466dd6c871ea3c89e0352c upstream.

Commit 8b592783 added a Thumb-2 variant of usracc which, when it is
called with \rept=2, calls usraccoff once with an offset of 0 and
secondly with a hard-coded offset of 4 in order to avoid incrementing
the pointer again. If \inc != 4 then we will store the data to the wrong
offset from \ptr. Luckily, the only caller that passes \rept=2 to this
function is __clear_user so we haven't been actively corrupting user data.

This patch fixes usracc to pass \inc instead of #4 to usraccoff
when it is called a second time.

Reported-by: Tony Thompson <tony.thompson@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
ARM: 6464/2: fix spinlock recursion in adjust_pte() 2010-12-09T21:33:20+00:00 Mika Westerberg mika.westerberg@iki.fi 2010-10-28T10:45:22+00:00 7c9dc749d0a5625ef1b76fbfa94c4845f998b44f commit 4e54d93d3c9846ba1c2644ad06463dafa690d1b7 upstream. When running following code in a machine which has VIVT caches and USE_SPLIT_PTLOCKS is not defined: fd = open("/etc/passwd", O_RDONLY); addr = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0); addr2 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0); v = *((int *)addr); we will hang in spinlock recursion in the page fault handler: BUG: spinlock recursion on CPU#0, mmap_test/717 lock: c5e295d8, .magic: dead4ead, .owner: mmap_test/717, .owner_cpu: 0 [<c0026604>] (unwind_backtrace+0x0/0xec) [<c014ee48>] (do_raw_spin_lock+0x40/0x140) [<c0027f68>] (update_mmu_cache+0x208/0x250) [<c0079db4>] (__do_fault+0x320/0x3ec) [<c007af7c>] (handle_mm_fault+0x2f0/0x6d8) [<c0027834>] (do_page_fault+0xdc/0x1cc) [<c00202d0>] (do_DataAbort+0x34/0x94) This comes from the fact that when USE_SPLIT_PTLOCKS is not defined, the only lock protecting the page tables is mm->page_table_lock which is already locked before update_mmu_cache() is called. Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 4e54d93d3c9846ba1c2644ad06463dafa690d1b7 upstream.

When running following code in a machine which has VIVT caches and
USE_SPLIT_PTLOCKS is not defined:

  fd = open("/etc/passwd", O_RDONLY);
  addr = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0);
  addr2 = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fd, 0);

  v = *((int *)addr);

we will hang in spinlock recursion in the page fault handler:

  BUG: spinlock recursion on CPU#0, mmap_test/717
  lock: c5e295d8, .magic: dead4ead, .owner: mmap_test/717,
                  .owner_cpu: 0
  [<c0026604>] (unwind_backtrace+0x0/0xec)
  [<c014ee48>] (do_raw_spin_lock+0x40/0x140)
  [<c0027f68>] (update_mmu_cache+0x208/0x250)
  [<c0079db4>] (__do_fault+0x320/0x3ec)
  [<c007af7c>] (handle_mm_fault+0x2f0/0x6d8)
  [<c0027834>] (do_page_fault+0xdc/0x1cc)
  [<c00202d0>] (do_DataAbort+0x34/0x94)

This comes from the fact that when USE_SPLIT_PTLOCKS is not defined,
the only lock protecting the page tables is mm->page_table_lock
which is already locked before update_mmu_cache() is called.

Signed-off-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
x86: Ignore trap bits on single step exceptions 2010-12-09T21:33:18+00:00 Frederic Weisbecker fweisbec@gmail.com 2010-11-11T20:18:43+00:00 c39b87a7108e27f558af2de04d9d70dbbe64155b commit 6c0aca288e726405b01dacb12cac556454d34b2a upstream. When a single step exception fires, the trap bits, used to signal hardware breakpoints, are in a random state. These trap bits might be set if another exception will follow, like a breakpoint in the next instruction, or a watchpoint in the previous one. Or there can be any junk there. So if we handle these trap bits during the single step exception, we are going to handle an exception twice, or we are going to handle junk. Just ignore them in this case. This fixes https://bugzilla.kernel.org/show_bug.cgi?id=21332 Reported-by: Michael Stefaniuc <mstefani@redhat.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Rafael J. Wysocki <rjw@sisk.pl> Cc: Maciej Rutecki <maciej.rutecki@gmail.com> Cc: Alexandre Julliard <julliard@winehq.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 6c0aca288e726405b01dacb12cac556454d34b2a upstream.

When a single step exception fires, the trap bits, used to
signal hardware breakpoints, are in a random state.

These trap bits might be set if another exception will follow,
like a breakpoint in the next instruction, or a watchpoint in the
previous one. Or there can be any junk there.

So if we handle these trap bits during the single step exception,
we are going to handle an exception twice, or we are going to
handle junk.

Just ignore them in this case.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=21332

Reported-by: Michael Stefaniuc <mstefani@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Maciej Rutecki <maciej.rutecki@gmail.com>
Cc: Alexandre Julliard <julliard@winehq.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
uml: disable winch irq before freeing handler data 2010-12-09T21:33:16+00:00 Will Newton will.newton@gmail.com 2010-11-24T20:56:55+00:00 4d88db53a9977e16cfa9b7315893401ff6eac7ee commit 69e83dad5207f8f03c9699e57e1febb114383cb8 upstream. Disable the winch irq early to make sure we don't take an interrupt part way through the freeing of the handler data, resulting in a crash on shutdown: winch_interrupt : read failed, errno = 9 fd 13 is losing SIGWINCH support ------------[ cut here ]------------ WARNING: at lib/list_debug.c:48 list_del+0xc6/0x100() list_del corruption, next is LIST_POISON1 (00100100) 082578c8: [<081fd77f>] dump_stack+0x22/0x24 082578e0: [<0807a18a>] warn_slowpath_common+0x5a/0x80 08257908: [<0807a23e>] warn_slowpath_fmt+0x2e/0x30 08257920: [<08172196>] list_del+0xc6/0x100 08257940: [<08060244>] free_winch+0x14/0x80 08257958: [<080606fb>] winch_interrupt+0xdb/0xe0 08257978: [<080a65b5>] handle_IRQ_event+0x35/0xe0 08257998: [<080a8717>] handle_edge_irq+0xb7/0x170 082579bc: [<08059bc4>] do_IRQ+0x34/0x50 082579d4: [<08059e1b>] sigio_handler+0x5b/0x80 082579ec: [<0806a374>] sig_handler_common+0x44/0xb0 08257a68: [<0806a538>] sig_handler+0x38/0x50 08257a78: [<0806a77c>] handle_signal+0x5c/0xa0 08257a9c: [<0806be28>] hard_handler+0x18/0x20 08257aac: [<00c14400>] 0xc14400 Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> 
commit 69e83dad5207f8f03c9699e57e1febb114383cb8 upstream.

Disable the winch irq early to make sure we don't take an interrupt part
way through the freeing of the handler data, resulting in a crash on
shutdown:

  winch_interrupt : read failed, errno = 9
  fd 13 is losing SIGWINCH support
  ------------[ cut here ]------------
  WARNING: at lib/list_debug.c:48 list_del+0xc6/0x100()
  list_del corruption, next is LIST_POISON1 (00100100)
  082578c8:  [<081fd77f>] dump_stack+0x22/0x24
  082578e0:  [<0807a18a>] warn_slowpath_common+0x5a/0x80
  08257908:  [<0807a23e>] warn_slowpath_fmt+0x2e/0x30
  08257920:  [<08172196>] list_del+0xc6/0x100
  08257940:  [<08060244>] free_winch+0x14/0x80
  08257958:  [<080606fb>] winch_interrupt+0xdb/0xe0
  08257978:  [<080a65b5>] handle_IRQ_event+0x35/0xe0
  08257998:  [<080a8717>] handle_edge_irq+0xb7/0x170
  082579bc:  [<08059bc4>] do_IRQ+0x34/0x50
  082579d4:  [<08059e1b>] sigio_handler+0x5b/0x80
  082579ec:  [<0806a374>] sig_handler_common+0x44/0xb0
  08257a68:  [<0806a538>] sig_handler+0x38/0x50
  08257a78:  [<0806a77c>] handle_signal+0x5c/0xa0
  08257a9c:  [<0806be28>] hard_handler+0x18/0x20
  08257aac:  [<00c14400>] 0xc14400

Signed-off-by: Will Newton <will.newton@gmail.com>
Acked-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>