diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1eb683f..7ee675a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1650,8 +1650,8 @@
 		unsigned long start_pfn)
 {
 	struct page *page;
-	int end_pfn = start_pfn + size;
-	int pfn;
+	unsigned long end_pfn = start_pfn + size;
+	unsigned long pfn;
 
 	for (pfn = start_pfn; pfn < end_pfn; pfn++, page++) {
 		if (!early_pfn_valid(pfn))