From: Yasunori Goto <y-goto@jp.fujitsu.com>

The BUG_ON() check at move_freepages() is wrong.  Its end_page is
start_page + MAX_ORDER_NR_PAGES.  So, it can be next zone.  BUG_ON() should
check "end_page - 1".

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/page_alloc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN mm/page_alloc.c~move-free-pages-between-lists-on-steal-fix-2 mm/page_alloc.c
--- a/mm/page_alloc.c~move-free-pages-between-lists-on-steal-fix-2
+++ a/mm/page_alloc.c
@@ -673,7 +673,7 @@ int move_freepages(struct zone *zone,
 	unsigned long order;
 	int blocks_moved = 0;
 
-	BUG_ON(page_zone(start_page) != page_zone(end_page));
+	BUG_ON(page_zone(start_page) != page_zone(end_page - 1));
 
 	for (page = start_page; page < end_page;) {
 		if (!PageBuddy(page)) {
_