3.3-stable review patch. If anyone has any objections, please let me know.
------------------ From: Chris Metcalf <[email protected]> commit 4998a6c0edce7fae9c0a5463f6ec3fa585258ee7 upstream. Commit 66aebce747eaf ("hugetlb: fix race condition in hugetlb_fault()") added code to avoid a race condition by elevating the page refcount in hugetlb_fault() while calling hugetlb_cow(). However, one code path in hugetlb_cow() includes an assertion that the page count is 1, whereas it may now also have the value 2 in this path. The consensus is that this BUG_ON has served its purpose, so rather than extending it to cover both cases, we just remove it. Signed-off-by: Chris Metcalf <[email protected]> Acked-by: Mel Gorman <[email protected]> Acked-by: Hillf Danton <[email protected]> Acked-by: Hugh Dickins <[email protected]> Cc: Michal Hocko <[email protected]> Cc: KAMEZAWA Hiroyuki <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- mm/hugetlb.c | 1 - 1 file changed, 1 deletion(-) --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2486,7 +2486,6 @@ retry_avoidcopy: if (outside_reserve) { BUG_ON(huge_pte_none(pte)); if (unmap_ref_private(mm, vma, old_page, address)) { - BUG_ON(page_count(old_page) != 1); BUG_ON(huge_pte_none(pte)); spin_lock(&mm->page_table_lock); ptep = huge_pte_offset(mm, address & huge_page_mask(h)); -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
