[GIT pull] perf/urgent for v5.15-rc2

From: Thomas Gleixner
Date: Sun Sep 19 2021 - 14:28:17 EST


Linus,

please pull the latest perf/urgent branch from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-2021-09-19

up to: b89a05b21f46: events: Reuse value read using READ_ONCE instead of re-reading it


A single fix for the perf core where a value read with READ_ONCE() was
checked and then reread which makes all the checks invalid. Reuse the
already read value instead.

Thanks,

tglx

------------------>
Baptiste Lepers (1):
events: Reuse value read using READ_ONCE instead of re-reading it


kernel/events/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 744e8726c5b2..0c000cb01eeb 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10193,7 +10193,7 @@ static void perf_event_addr_filters_apply(struct perf_event *event)
return;

if (ifh->nr_file_filters) {
- mm = get_task_mm(event->ctx->task);
+ mm = get_task_mm(task);
if (!mm)
goto restart;