-	    (!q->elevator && nr > q->tag_set->queue_depth)) {
+	    (!q->elevator && nr > set->queue_depth)) {
 		ret = -EINVAL;
 		goto unlock;
 	}
 
+	memflags = blk_mq_freeze_queue(q);
+	mutex_lock(&q->elevator_lock);
+
 	err = blk_mq_update_nr_requests(disk->queue, nr);
 	if (err)
 		ret = err;
 
-unlock:
 	mutex_unlock(&q->elevator_lock);
 	blk_mq_unfreeze_queue(q, memflags);
+
+unlock:
+	up_write(&set->update_nr_hwq_lock);
 	return ret;
 }
 
-- 
2.51.0[PATCH 6.17 127/563] blk-mq: convert to serialize updating nr_requests with update_nr_hwq_lockGreg Kroah-Hartman <gregkh@linuxfoundation.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined undefined–eƒ˜z