From 1f64d69c7ad2e48e697493e45590679f7a69b7b2 Mon Sep 17 00:00:00 2001 From: Dean Nelson <dnelson@redhat.com> Date: Thu, 2 Dec 2010 14:31:12 -0800 Subject: [PATCH] mm/hugetlb.c: avoid double unlock_page() in hugetlb_fault() Have hugetlb_fault() call unlock_page(page) only if it had previously called lock_page(page). Setting CONFIG_DEBUG_VM=y and then running the libhugetlbfs test suite, resulted in the tripping of VM_BUG_ON(!PageLocked(page)) in unlock_page() having been called by hugetlb_fault() when page == pagecache_page. This patch remedied the problem. Signed-off-by: Dean Nelson <dnelson@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- mm/hugetlb.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index c4a3558589ab..85855240933d 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2738,7 +2738,8 @@ out_page_table_lock: unlock_page(pagecache_page); put_page(pagecache_page); } - unlock_page(page); + if (page != pagecache_page) + unlock_page(page); out_mutex: mutex_unlock(&hugetlb_instantiation_mutex); -- GitLab