diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 0d7ab20c58dffc40d5c56c9427b7dd7f090c8bd3..0907d9eb864ee79750c5f04dd8206672a659c3b2 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1466,7 +1466,7 @@ static void __map_bio(struct dm_target_io *tio)
 		md = tio->io->md;
 		dec_pending(tio->io, r);
 		free_tio(md, tio);
-	} else if (r) {
+	} else if (r != DM_MAPIO_SUBMITTED) {
 		DMWARN("unimplemented target map return value: %d", r);
 		BUG();
 	}