diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index f2e574dbc300..2a56124dbc28 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -176,6 +176,9 @@ int bdi_register(struct backing_dev_info *bdi, struct device *parent,
 	int ret = 0;
 	struct device *dev;
 
+	if (WARN_ON(bdi->dev))
+		goto exit;
+
 	va_start(args, fmt);
 	dev = device_create_vargs(bdi_class, parent, MKDEV(0, 0), bdi, fmt, args);
 	va_end(args);