lkml.org 
[lkml]   [2015]   [Mar]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[GIT PULL] perf fix
Linus,

Please pull the latest perf-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus

# HEAD: d525211f9d1be8b523ec7633f080f2116f5ea536 perf: Fix irq_work 'tail' recursion

A perf kernel side fix for a fuzzer triggered lockup.

Thanks,

Ingo

------------------>
Peter Zijlstra (1):
perf: Fix irq_work 'tail' recursion


kernel/events/core.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 453ef61311d4..2fabc0627165 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4574,6 +4574,13 @@ static void perf_pending_event(struct irq_work *entry)
{
struct perf_event *event = container_of(entry,
struct perf_event, pending);
+ int rctx;
+
+ rctx = perf_swevent_get_recursion_context();
+ /*
+ * If we 'fail' here, that's OK, it means recursion is already disabled
+ * and we won't recurse 'further'.
+ */

if (event->pending_disable) {
event->pending_disable = 0;
@@ -4584,6 +4591,9 @@ static void perf_pending_event(struct irq_work *entry)
event->pending_wakeup = 0;
perf_event_wakeup(event);
}
+
+ if (rctx >= 0)
+ perf_swevent_put_recursion_context(rctx);
}

/*

\
 
 \ /
  Last update: 2015-03-28 11:41    [W:0.041 / U:0.120 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site