2013-04-27 07:50:19

by Ingo Molnar

[permalink] [raw]
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: c79aa0d96548aee50570209eb2d45c8f4ac49230 events: Protect access via task_subsys_state_check()

This fix adds missing RCU read protection.

Thanks,

Ingo

------------------>
Paul E. McKenney (1):
events: Protect access via task_subsys_state_check()


kernel/events/core.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 4d3124b..9fcb094 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4596,6 +4596,7 @@ void perf_event_comm(struct task_struct *task)
struct perf_event_context *ctx;
int ctxn;

+ rcu_read_lock();
for_each_task_context_nr(ctxn) {
ctx = task->perf_event_ctxp[ctxn];
if (!ctx)
@@ -4603,6 +4604,7 @@ void perf_event_comm(struct task_struct *task)

perf_event_enable_on_exec(ctx);
}
+ rcu_read_unlock();

if (!atomic_read(&nr_comm_events))
return;