Messages in this thread Patch in this message | | | From | wency@cn ... | Subject | [RFC v8 PATCH 13/20] memory-hotplug: check page type in get_page_bootmem | Date | Tue, 28 Aug 2012 18:00:20 +0800 |
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From: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
There is a possibility that get_page_bootmem() is called to the same page many times. So when get_page_bootmem is called to the same page, the function only increments page->_count.
CC: David Rientjes <rientjes@google.com> CC: Jiang Liu <liuj97@gmail.com> CC: Len Brown <len.brown@intel.com> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Paul Mackerras <paulus@samba.org> CC: Christoph Lameter <cl@linux.com> Cc: Minchan Kim <minchan.kim@gmail.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> CC: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> --- mm/memory_hotplug.c | 15 +++++++++++---- 1 files changed, 11 insertions(+), 4 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 5f9f8c7..d85af6d 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -95,10 +95,17 @@ static void release_memory_resource(struct resource *res) static void get_page_bootmem(unsigned long info, struct page *page, unsigned long type) { - page->lru.next = (struct list_head *) type; - SetPagePrivate(page); - set_page_private(page, info); - atomic_inc(&page->_count); + unsigned long page_type; + + page_type = (unsigned long) page->lru.next; + if (page_type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || + page_type > MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE){ + page->lru.next = (struct list_head *) type; + SetPagePrivate(page); + set_page_private(page, info); + atomic_inc(&page->_count); + } else + atomic_inc(&page->_count); } /* reference to __meminit __free_pages_bootmem is valid -- 1.7.1
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