diff --git a/block/blk-mq.c b/block/blk-mq.c
index b70488e4db94..95993c4efa49 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -476,6 +476,8 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q,
 	if (!blk_mq_hw_queue_mapped(data.hctx))
 		goto out_queue_exit;
 	cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask);
+	if (cpu >= nr_cpu_ids)
+		goto out_queue_exit;
 	data.ctx = __blk_mq_get_ctx(q, cpu);
 
 	if (!q->elevator)