Commit 25a6df95 authored May 30, 2006 by Yasunori Goto Committed by Linus Torvalds May 31, 2006

[PATCH] spanned_pages is not updated at a case of memory hot-add



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

If hot-added memory's address is smaller than old area, spanned_pages will
not be updated.  It must be fixed.

example) Old zone_start_pfn = 0x60000, and spanned_pages = 0x10000
         Added new memory's start_pfn = 0x50000, and end_pfn = 0x60000

  new spanned_pages will be still 0x10000 by old code.
  (It should be updated to 0x20000.) Because old_zone_end_pfn will be
  0x70000, and end_pfn smaller than it. So, spanned_pages will not be
  updated.

In current code, spanned_pages is updated only when end_pfn is updated.
But, it should be updated by subtraction between bigger end_pfn and new
zone_start_pfn.

Signed-off-by: Yasunori Goto <y-goto@jp.fujitsu.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 308af929

mm/memory_hotplug.c

+4 −4

Original line number	Diff line number	Diff line
		@@ -91,8 +91,8 @@ static void grow_zone_span(struct zone *zone,
		if (start_pfn < zone->zone_start_pfn)
		zone->zone_start_pfn = start_pfn;

		if (end_pfn > old_zone_end_pfn)
		zone->spanned_pages = end_pfn - zone->zone_start_pfn;
		zone->spanned_pages = max(old_zone_end_pfn, end_pfn) -
		zone->zone_start_pfn;

		zone_span_writeunlock(zone);
		}
		@@ -106,8 +106,8 @@ static void grow_pgdat_span(struct pglist_data *pgdat,
		if (start_pfn < pgdat->node_start_pfn)
		pgdat->node_start_pfn = start_pfn;

		if (end_pfn > old_pgdat_end_pfn)
		pgdat->node_spanned_pages = end_pfn - pgdat->node_start_pfn;
		pgdat->node_spanned_pages = max(old_pgdat_end_pfn, end_pfn) -
		pgdat->node_start_pfn;
		}

		int online_pages(unsigned long pfn, unsigned long nr_pages)

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