diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 35082ae3..4ebdcbd4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -6,7 +6,7 @@
 #include <linux/kobject.h>
 #include <linux/types.h>
 
-#define BIO_MAX_VECS	256
+#define BIO_MAX_VECS	256U
 
 typedef unsigned fmode_t;