From: Davidlohr Bueso <dave@xxxxxxxxxxxx> This patch has been added to the 4.1 stable tree. If you have any objections, please let us know. =============== [ Upstream commit fe1bce9e2107ba3a8faffe572483b6974201a0e6 ] Otherwise an incoming waker on the dest hash bucket can miss the waiter adding itself to the plist during the lockless check optimization (small window but still the correct way of doing this); similarly to the decrement counterpart. Suggested-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Cc: bigeasy@xxxxxxxxxxxxx Cc: dvhart@xxxxxxxxxxxxx Cc: stable@xxxxxxxxxx Link: http://lkml.kernel.org/r/1461208164-29150-1-git-send-email-dave@xxxxxxxxxxxx Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- kernel/futex.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/futex.c b/kernel/futex.c index 46b168e..2214b70 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -1381,8 +1381,8 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1, if (likely(&hb1->chain != &hb2->chain)) { plist_del(&q->list, &hb1->chain); hb_waiters_dec(hb1); - plist_add(&q->list, &hb2->chain); hb_waiters_inc(hb2); + plist_add(&q->list, &hb2->chain); q->lock_ptr = &hb2->lock; } get_futex_key_refs(key2); -- 2.5.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html