blk_unregister_queue() must protect against any modifications of q->queue_flags (not just those performed in blk-sysfs.c). Therefore q->queue_lock needs to be used rather than q->sysfs_lock. Fixes: e9a823fb34a8b ("block: fix warning when I/O elevator is changed as request_queue is being removed") Cc: stable@xxxxxxxxxxxxxxx # 4.14+ Reported-by: Bart Van Assche <Bart.VanAssche@xxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> --- block/blk-sysfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 870484eaed1f..52f57539f1c7 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -929,9 +929,9 @@ void blk_unregister_queue(struct gendisk *disk) if (WARN_ON(!q)) return; - mutex_lock(&q->sysfs_lock); + spin_lock_irq(q->queue_lock); queue_flag_clear_unlocked(QUEUE_FLAG_REGISTERED, q); - mutex_unlock(&q->sysfs_lock); + spin_unlock_irq(q->queue_lock); wbt_exit(q); -- 2.15.0