mm, page_alloc: move_freepages should not examine struct page of reserved memory
[sfrench/cifs-2.6.git] / mm / page_alloc.c
index 272c6de1bf4ead31c22aca202940da00bc8eaf8b..9c9194959271cfc0d9214bf60bb09b96c5b1a96a 100644 (file)
@@ -2238,27 +2238,12 @@ static int move_freepages(struct zone *zone,
        unsigned int order;
        int pages_moved = 0;
 
        unsigned int order;
        int pages_moved = 0;
 
-#ifndef CONFIG_HOLES_IN_ZONE
-       /*
-        * page_zone is not safe to call in this context when
-        * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant
-        * anyway as we check zone boundaries in move_freepages_block().
-        * Remove at a later date when no bug reports exist related to
-        * grouping pages by mobility
-        */
-       VM_BUG_ON(pfn_valid(page_to_pfn(start_page)) &&
-                 pfn_valid(page_to_pfn(end_page)) &&
-                 page_zone(start_page) != page_zone(end_page));
-#endif
        for (page = start_page; page <= end_page;) {
                if (!pfn_valid_within(page_to_pfn(page))) {
                        page++;
                        continue;
                }
 
        for (page = start_page; page <= end_page;) {
                if (!pfn_valid_within(page_to_pfn(page))) {
                        page++;
                        continue;
                }
 
-               /* Make sure we are not inadvertently changing nodes */
-               VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
-
                if (!PageBuddy(page)) {
                        /*
                         * We assume that pages that could be isolated for
                if (!PageBuddy(page)) {
                        /*
                         * We assume that pages that could be isolated for
@@ -2273,6 +2258,10 @@ static int move_freepages(struct zone *zone,
                        continue;
                }
 
                        continue;
                }
 
+               /* Make sure we are not inadvertently changing nodes */
+               VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
+               VM_BUG_ON_PAGE(page_zone(page) != zone, page);
+
                order = page_order(page);
                move_to_free_area(page, &zone->free_area[order], migratetype);
                page += 1 << order;
                order = page_order(page);
                move_to_free_area(page, &zone->free_area[order], migratetype);
                page += 1 << order;