diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 3be79dc..b3c7864 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -16,7 +16,7 @@
 #include <linux/mutex.h>
 #include <linux/bootmem.h>
 #include <linux/sysfs.h>
-
+#include <asm/io.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>