From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Mon, 22 Apr 2013 15:33:39 +0000 (-0700)
Subject: 3.0-stable patches
X-Git-Tag: v3.8.9~20
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=2bdcf33b3e504391fe5085d6b6ad353bdcb506f5;p=thirdparty%2Fkernel%2Fstable-queue.git

3.0-stable patches

added patches:
	sched-convert-bug_on-s-in-try_to_wake_up_local-to-warn_on_once-s.patch
---

diff --git a/queue-3.0/sched-convert-bug_on-s-in-try_to_wake_up_local-to-warn_on_once-s.patch b/queue-3.0/sched-convert-bug_on-s-in-try_to_wake_up_local-to-warn_on_once-s.patch
new file mode 100644
index 00000000000..aad0d8e6b9c
--- /dev/null
+++ b/queue-3.0/sched-convert-bug_on-s-in-try_to_wake_up_local-to-warn_on_once-s.patch
@@ -0,0 +1,45 @@
+From 383efcd00053ec40023010ce5034bd702e7ab373 Mon Sep 17 00:00:00 2001
+From: Tejun Heo <tj@kernel.org>
+Date: Mon, 18 Mar 2013 12:22:34 -0700
+Subject: sched: Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s
+
+From: Tejun Heo <tj@kernel.org>
+
+commit 383efcd00053ec40023010ce5034bd702e7ab373 upstream.
+
+try_to_wake_up_local() should only be invoked to wake up another
+task in the same runqueue and BUG_ON()s are used to enforce the
+rule. Missing try_to_wake_up_local() can stall workqueue
+execution but such stalls are likely to be finite either by
+another work item being queued or the one blocked getting
+unblocked.  There's no reason to trigger BUG while holding rq
+lock crashing the whole system.
+
+Convert BUG_ON()s in try_to_wake_up_local() to WARN_ON_ONCE()s.
+
+Signed-off-by: Tejun Heo <tj@kernel.org>
+Acked-by: Steven Rostedt <rostedt@goodmis.org>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Link: http://lkml.kernel.org/r/20130318192234.GD3042@htj.dyndns.org
+Signed-off-by: Ingo Molnar <mingo@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ kernel/sched.c |    6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/kernel/sched.c
++++ b/kernel/sched.c
+@@ -2743,8 +2743,10 @@ static void try_to_wake_up_local(struct
+ {
+ 	struct rq *rq = task_rq(p);
+ 
+-	BUG_ON(rq != this_rq());
+-	BUG_ON(p == current);
++	if (WARN_ON_ONCE(rq != this_rq()) ||
++	    WARN_ON_ONCE(p == current))
++		return;
++
+ 	lockdep_assert_held(&rq->lock);
+ 
+ 	if (!raw_spin_trylock(&p->pi_lock)) {
diff --git a/queue-3.0/series b/queue-3.0/series
index 4ca2e007d1f..31ef644a443 100644
--- a/queue-3.0/series
+++ b/queue-3.0/series
@@ -11,3 +11,4 @@ kvm-allow-cross-page-reads-and-writes-from-cached-translations.patch
 arm-7696-1-fix-kexec-by-setting-outer_cache.inv_all-for-feroceon.patch
 ath9k_htc-accept-1.x-firmware-newer-than-1.3.patch
 
+sched-convert-bug_on-s-in-try_to_wake_up_local-to-warn_on_once-s.patch