| Date | Wed, 03 Aug 2011 15:01:00 -0700 | From | Greg KH <> | Subject | [040/102] perf: Fix software event overflow |
| |
3.0-stable review patch. If anyone has any objections, please let us know.
------------------
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
The below patch is for -stable only, upstream has a much larger patch that contains the below hunk in commit a8b0ca17b80e92faab46ee7179ba9e99ccb61233
Vince found that under certain circumstances software event overflows go wrong and deadlock. Avoid trying to delete a timer from the timer callback.
Reported-by: Vince Weaver <vweaver1@eecs.utk.edu> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
--- kernel/events/core.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)
--- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5016,11 +5016,8 @@ static int __perf_event_overflow(struct if (events && atomic_dec_and_test(&event->event_limit)) { ret = 1; event->pending_kill = POLL_HUP; - if (nmi) { - event->pending_disable = 1; - irq_work_queue(&event->pending); - } else - perf_event_disable(event); + event->pending_disable = 1; + irq_work_queue(&event->pending); } if (event->overflow_handler)
|