4.4-stable review patch. If anyone has any objections, please let me know.
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From: Ming Lei ming.lei@redhat.com
[ Upstream commit 34d9715ac1edd50285168dd8d80c972739a4f6a4 ]
Once blk_set_queue_dying() is done in blk_cleanup_queue(), we call blk_freeze_queue() and wait for q->q_usage_counter becoming zero. But if there are tasks blocked in get_request(), q->q_usage_counter can never become zero. So we have to wake up all these tasks in blk_set_queue_dying() first.
Fixes: 3ef28e83ab157997 ("block: generic request_queue reference counting") Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/blk-core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/block/blk-core.c +++ b/block/blk-core.c @@ -526,8 +526,8 @@ void blk_set_queue_dying(struct request_
blk_queue_for_each_rl(rl, q) { if (rl->rq_pool) { - wake_up(&rl->wait[BLK_RW_SYNC]); - wake_up(&rl->wait[BLK_RW_ASYNC]); + wake_up_all(&rl->wait[BLK_RW_SYNC]); + wake_up_all(&rl->wait[BLK_RW_ASYNC]); } } }