mm/hugetlb.c: correct missing private flag clearing
authorJoonsoo Kim <iamjoonsoo.kim@lge.com>
Wed, 16 Oct 2013 20:46:48 +0000 (13:46 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 17 Oct 2013 04:35:52 +0000 (21:35 -0700)
We should clear the page's private flag when returing the page to the
hugepage pool.  Otherwise, marked hugepage can be allocated to the user
who tries to allocate the non-reserved hugepage.  If this user fail to
map this hugepage, he would try to return the page to the hugepage pool.
Since this page has a private flag, resv_huge_pages would mistakenly
increase.  This patch fixes this situation.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Davidlohr Bueso <davidlohr.bueso@hp.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hillf Danton <dhillf@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hugetlb.c

index b49579c7f2a550462c334f97907f2fc131a65e00..691f2264a6ce23cfd10dbb570f5342fee2d25bc5 100644 (file)
@@ -653,6 +653,7 @@ static void free_huge_page(struct page *page)
        BUG_ON(page_count(page));
        BUG_ON(page_mapcount(page));
        restore_reserve = PagePrivate(page);
+       ClearPagePrivate(page);
 
        spin_lock(&hugetlb_lock);
        hugetlb_cgroup_uncharge_page(hstate_index(h),