This is a note to let you know that I've just added the patch titled
af_unix: Annotate data-race of gc_in_progress in wait_for_unix_gc().
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
af_unix-annotate-data-race-of-gc_in_progress-in-wait.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit b88e1dedcbdeef203c17b12d136f3a3d0ae6cf70
Author: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Date: Tue Jan 23 09:08:52 2024 -0800
af_unix: Annotate data-race of gc_in_progress in wait_for_unix_gc().
[ Upstream commit 31e03207119a535d0b0e3b3a7f91983aeb2cb14d ]
gc_in_progress is changed under spin_lock(&unix_gc_lock),
but wait_for_unix_gc() reads it locklessly.
Let's use READ_ONCE().
Fixes: 5f23b734963e ("net: Fix soft lockups/OOM issues w/ unix garbage collector")
Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240123170856.41348-2-kuniyu@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/unix/garbage.c b/net/unix/garbage.c
index dc27635403932..9121a4d5436d5 100644
--- a/net/unix/garbage.c
+++ b/net/unix/garbage.c
@@ -198,7 +198,7 @@ void wait_for_unix_gc(void)
if (READ_ONCE(unix_tot_inflight) > UNIX_INFLIGHT_TRIGGER_GC &&
!READ_ONCE(gc_in_progress))
unix_gc();
- wait_event(unix_gc_wait, gc_in_progress == false);
+ wait_event(unix_gc_wait, !READ_ONCE(gc_in_progress));
}
/* The external entry point: unix_gc() */
