Commit 86051ca5 authored by KAMEZAWA Hiroyuki's avatar KAMEZAWA Hiroyuki Committed by Linus Torvalds
Browse files

mm: fix usemap initialization 



usemap must be initialized only when pfn is within zone.  If not, it corrupts
memory.

And this patch also reduces the number of calls to set_pageblock_migratetype()
from
	(pfn & (pageblock_nr_pages -1)
to
	!(pfn & (pageblock_nr_pages-1)
it should be called once per pageblock.

Signed-off-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: default avatarMel Gorman <mel@csn.ul.ie>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Shi Weihua <shiwh@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: <stable@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a01e035e

mm/page_alloc.c

+12 −2
Original line number Diff line number Diff line
@@ -2524,7 +2524,9 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, 
	struct page *page;

	unsigned long end_pfn = start_pfn + size;

	unsigned long pfn;

	struct zone *z;



	z = &NODE_DATA(nid)->node_zones[zone];

	for (pfn = start_pfn; pfn < end_pfn; pfn++) {

		/*

		 * There can be holes in boot-time mem_map[]s
@@ -2542,7 +2544,6 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, 
		init_page_count(page);

		reset_page_mapcount(page);

		SetPageReserved(page);



		/*

		 * Mark the block movable so that blocks are reserved for

		 * movable at startup. This will force kernel allocations
@@ -2551,8 +2552,15 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, 
		 * kernel allocations are made. Later some blocks near

		 * the start are marked MIGRATE_RESERVE by

		 * setup_zone_migrate_reserve()

		 */

		if ((pfn & (pageblock_nr_pages-1)))

		 *

		 * bitmap is created for zone's valid pfn range. but memmap

		 * can be created for invalid pages (for alignment)

		 * check here not to call set_pageblock_migratetype() against

		 * pfn out of zone.

		 */

		if ((z->zone_start_pfn <= pfn)

		    && (pfn < z->zone_start_pfn + z->spanned_pages)

		    && !(pfn & (pageblock_nr_pages - 1)))

			set_pageblock_migratetype(page, MIGRATE_MOVABLE);



		INIT_LIST_HEAD(&page->lru);
@@ -4464,6 +4472,8 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags, 
	pfn = page_to_pfn(page);

	bitmap = get_pageblock_bitmap(zone, pfn);

	bitidx = pfn_to_bitidx(zone, pfn);

	VM_BUG_ON(pfn < zone->zone_start_pfn);

	VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages);



	for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)

		if (flags & value)

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