mm/hwpoison: fix fail isolate hugetlbfs page w/ refcount held

Hugetlbfs pages will get a refcount in get_any_page() or
madvise_hwpoison() if soft offlining through madvise.  The refcount which
is held by the soft offline path should be released if we fail to isolate
hugetlbfs pages.

Fix it by reducing the refcount for both isolation success and failure.

Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: <stable@vger.kernel.org>	[3.9+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Wanpeng Li 2015-08-14 15:34:59 -07:00 committed by Linus Torvalds
parent 4f32be677b
commit 036138080a

View File

@ -1569,13 +1569,12 @@ static int soft_offline_huge_page(struct page *page, int flags)
unlock_page(hpage);
ret = isolate_huge_page(hpage, &pagelist);
if (ret) {
/*
* get_any_page() and isolate_huge_page() takes a refcount each,
* so need to drop one here.
*/
put_page(hpage);
} else {
/*
* get_any_page() and isolate_huge_page() takes a refcount each,
* so need to drop one here.
*/
put_page(hpage);
if (!ret) {
pr_info("soft offline: %#lx hugepage failed to isolate\n", pfn);
return -EBUSY;
}