From 1b856086813be9371929b6cc62045f9fd470f5a0 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Tue, 16 Aug 2016 16:48:36 -0700 Subject: [PATCH] block: Fix race triggered by blk_set_queue_dying() blk_set_queue_dying() can be called while another thread is submitting I/O or changing queue flags, e.g. through dm_stop_queue(). Hence protect the QUEUE_FLAG_DYING flag change with locking. Signed-off-by: Bart Van Assche Cc: Christoph Hellwig Cc: Mike Snitzer Cc: stable Signed-off-by: Jens Axboe --- block/blk-core.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/blk-core.c b/block/blk-core.c index 999442e..36c7ac3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -515,7 +515,9 @@ EXPORT_SYMBOL_GPL(blk_queue_bypass_end); void blk_set_queue_dying(struct request_queue *q) { - queue_flag_set_unlocked(QUEUE_FLAG_DYING, q); + spin_lock_irq(q->queue_lock); + queue_flag_set(QUEUE_FLAG_DYING, q); + spin_unlock_irq(q->queue_lock); if (q->mq_ops) blk_mq_wake_waiters(q); -- 2.7.4