diff --git a/block/blk-mq.c b/block/blk-mq.c
index c0ec1938feee..92aae03103b7 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2782,6 +2782,9 @@ static inline struct request *blk_mq_get_cached_request(struct request_queue *q,
 
 static void bio_set_ioprio(struct bio *bio)
 {
+	/* Nobody set ioprio so far? Initialize it based on task's nice value */
+	if (IOPRIO_PRIO_CLASS(bio->bi_ioprio) == IOPRIO_CLASS_NONE)
+		bio->bi_ioprio = get_current_ioprio();
 	blkcg_set_ioprio(bio);
 }