diff --git a/block/blk-wbt.c b/block/blk-wbt.c
index c9358f1..84507d3 100644
--- a/block/blk-wbt.c
+++ b/block/blk-wbt.c
@@ -540,6 +540,9 @@ static enum wbt_flags bio_to_wbt_flags(struct rq_wb *rwb, struct bio *bio)
 {
 	enum wbt_flags flags = 0;
 
+	if (!rwb_enabled(rwb))
+		return 0;
+
 	if (bio_op(bio) == REQ_OP_READ) {
 		flags = WBT_READ;
 	} else if (wbt_should_throttle(rwb, bio)) {