-stable review patch. If anyone has any objections, please let us know.
---------------------
From: Andy Whitcroft <[email protected]>
When we free a page via free_huge_page and we detect that we are in surplus
the page will be returned to the buddy. After this we no longer own the page.
However at the end free_huge_page we clear out our mapping pointer from
page private. Even where the page is not a surplus we free the page to
the hugepage pool, drop the pool locks and then clear page private. In
either case the page may have been reallocated. BAD.
Make sure we clear out page private before we free the page.
Signed-off-by: Andy Whitcroft <[email protected]>
Acked-by: Adam Litke <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Chris Wright <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
mm/hugetlb.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -119,6 +119,7 @@ static void free_huge_page(struct page *
struct address_space *mapping;
mapping = (struct address_space *) page_private(page);
+ set_page_private(page, 0);
BUG_ON(page_count(page));
INIT_LIST_HEAD(&page->lru);
@@ -133,7 +134,6 @@ static void free_huge_page(struct page *
spin_unlock(&hugetlb_lock);
if (mapping)
hugetlb_put_quota(mapping, 1);
- set_page_private(page, 0);
}
/*
--