linux-toradex.git, branch v2.6.33.8

Linux 2.6.33.8

2011-03-21T19:49:43+00:00

isdn: avoid calling tty_ldisc_flush() in atomic context

2011-03-21T19:45:53+00:00

commit bc10f96757bd6ab3721510df8defa8f21c32f974 upstream.

Remove the call to tty_ldisc_flush() from the RESULT_NO_CARRIER
branch of isdn_tty_modem_result(), as already proposed in commit
00409bb045887ec5e7b9e351bc080c38ab6bfd33.
This avoids a "sleeping function called from invalid context" BUG
when the hardware driver calls the statcallb() callback with
command==ISDN_STAT_DHUP in atomic context, which in turn calls
isdn_tty_modem_result(RESULT_NO_CARRIER, ~), and from there,
tty_ldisc_flush() which may sleep.

Signed-off-by: Tilman Schmidt 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

x86: Flush TLB if PGD entry is changed in i386 PAE mode

2011-03-21T19:45:53+00:00

commit 4981d01eada5354d81c8929d5b2836829ba3df7b upstream.

According to intel CPU manual, every time PGD entry is changed in i386 PAE
mode, we need do a full TLB flush. Current code follows this and there is
comment for this too in the code.

But current code misses the multi-threaded case. A changed page table
might be used by several CPUs, every such CPU should flush TLB. Usually
this isn't a problem, because we prepopulate all PGD entries at process
fork. But when the process does munmap and follows new mmap, this issue
will be triggered.

When it happens, some CPUs keep doing page faults:

  http://marc.info/?l=linux-kernel&m=129915020508238&w=2

Reported-by: Yasunori Goto
Tested-by: Yasunori Goto
Reviewed-by: Rik van Riel 
Signed-off-by: Shaohua Li
Cc: Mallick Asit K 
Cc: Linus Torvalds 
Cc: Andrew Morton 
Cc: linux-mm 
LKML-Reference: <1300246649.2337.95.camel@sli10-conroe>
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

call_function_many: add missing ordering

2011-03-21T19:45:53+00:00

commit 45a5791920ae643eafc02e2eedef1a58e341b736 upstream.

Paul McKenney's review pointed out two problems with the barriers in the
2.6.38 update to the smp call function many code.

First, a barrier that would force the func and info members of data to
be visible before their consumption in the interrupt handler was
missing.  This can be solved by adding a smp_wmb between setting the
func and info members and setting setting the cpumask; this will pair
with the existing and required smp_rmb ordering the cpumask read before
the read of refs.  This placement avoids the need a second smp_rmb in
the interrupt handler which would be executed on each of the N cpus
executing the call request.  (I was thinking this barrier was present
but was not).

Second, the previous write to refs (establishing the zero that we the
interrupt handler was testing from all cpus) was performed by a third
party cpu.  This would invoke transitivity which, as a recient or
concurrent addition to memory-barriers.txt now explicitly states, would
require a full smp_mb().

However, we know the cpumask will only be set by one cpu (the data
owner) and any preivous iteration of the mask would have cleared by the
reading cpu.  By redundantly writing refs to 0 on the owning cpu before
the smp_wmb, the write to refs will follow the same path as the writes
that set the cpumask, which in turn allows us to keep the barrier in the
interrupt handler a smp_rmb instead of promoting it to a smp_mb (which
will be be executed by N cpus for each of the possible M elements on the
list).

I moved and expanded the comment about our (ab)use of the rcu list
primitives for the concurrent walk earlier into this function.  I
considered moving the first two paragraphs to the queue list head and
lock, but felt it would have been too disconected from the code.

Cc: Paul McKinney 
Signed-off-by: Milton Miller 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

call_function_many: fix list delete vs add race

2011-03-21T19:45:52+00:00

commit e6cd1e07a185d5f9b0aa75e020df02d3c1c44940 upstream.

Peter pointed out there was nothing preventing the list_del_rcu in
smp_call_function_interrupt from running before the list_add_rcu in
smp_call_function_many.

Fix this by not setting refs until we have gotten the lock for the list.
Take advantage of the wmb in list_add_rcu to save an explicit additional
one.

I tried to force this race with a udelay before the lock & list_add and
by mixing all 64 online cpus with just 3 random cpus in the mask, but
was unsuccessful.  Still, inspection shows a valid race, and the fix is
a extension of the existing protection window in the current code.

Reported-by: Peter Zijlstra 
Signed-off-by: Milton Miller 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ext3: Always set dx_node's fake_dirent explicitly.

2011-03-21T19:45:52+00:00

commit d7433142b63d727b5a217c37b1a1468b116a9771 upstream.

(crossport of 1f7bebb9e911d870fa8f997ddff838e82b5715ea
by Andreas Schlick )

When ext3_dx_add_entry() has to split an index node, it has to ensure that
name_len of dx_node's fake_dirent is also zero, because otherwise e2fsck
won't recognise it as an intermediate htree node and consider the htree to
be corrupted.

Signed-off-by: Eric Sandeen 
Signed-off-by: Jan Kara 
Signed-off-by: Greg Kroah-Hartman

perf, powerpc: Handle events that raise an exception without overflowing

2011-03-21T19:45:51+00:00

commit 0837e3242c73566fc1c0196b4ec61779c25ffc93 upstream.

Events on POWER7 can roll back if a speculative event doesn't
eventually complete. Unfortunately in some rare cases they will
raise a performance monitor exception. We need to catch this to
ensure we reset the PMC. In all cases the PMC will be 256 or less
cycles from overflow.

Signed-off-by: Anton Blanchard 
Signed-off-by: Peter Zijlstra 
LKML-Reference: <20110309143842.6c22845e@kryten>
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

SUNRPC: Ensure we always run the tk_callback before tk_action

2011-03-21T19:45:51+00:00

commit e020c6800c9621a77223bf2c1ff68180e41e8ebf upstream.

This fixes a race in which the task->tk_callback() puts the rpc_task
to sleep, setting a new callback. Under certain circumstances, the current
code may end up executing the task->tk_action before it gets round to the
callback.

Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

scsi_dh_alua: fix deadlock in stpg_endio

2011-03-21T19:45:51+00:00

commit ed0f36bc5719b25659b637f80ceea85494b84502 upstream.

The use of blk_execute_rq_nowait() implies __blk_put_request() is needed
in stpg_endio() rather than blk_put_request() -- blk_finish_request() is
called with queue lock already held.

Signed-off-by: Joseph Gruher 
Signed-off-by: Ilgu Hong 
Signed-off-by: Mike Snitzer 
Signed-off-by: James Bottomley 
Signed-off-by: Greg Kroah-Hartman

ALSA: ctxfi - Clear input settings before initialization

2011-03-21T19:45:50+00:00

commit efed5f26664f93991c929d5bb343e65f900d72bc upstream.

Clear input settings before initialization.

Signed-off-by: Przemyslaw Bruski 
Signed-off-by: Takashi Iwai 
Signed-off-by: Greg Kroah-Hartman