diff --git a/block/blk-mq.c b/block/blk-mq.c
index dec70ca0aafd..03a747105682 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2336,15 +2336,15 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 
 	blk_mq_init_cpu_queues(q, set->nr_hw_queues);
 
-	get_online_cpus();
 	mutex_lock(&all_q_mutex);
+	get_online_cpus();
 
 	list_add_tail(&q->all_q_node, &all_q_list);
 	blk_mq_add_queue_tag_set(set, q);
 	blk_mq_map_swqueue(q, cpu_online_mask);
 
-	mutex_unlock(&all_q_mutex);
 	put_online_cpus();
+	mutex_unlock(&all_q_mutex);
 
 	if (!(set->flags & BLK_MQ_F_NO_SCHED)) {
 		int ret;