From 56f2fb147659e05b1e87b99791bf44b988d38545 Mon Sep 17 00:00:00 2001 From: Naoya Horiguchi Date: Wed, 12 Dec 2012 13:52:33 -0800 Subject: [PATCH] mm/hugetlb.c: fix warning on freeing hwpoisoned hugepage Fix the warning from __list_del_entry() which is triggered when a process tries to do free_huge_page() for a hwpoisoned hugepage. free_huge_page() can be called for hwpoisoned hugepage from unpoison_memory(). This function gets refcount once and clears PageHWPoison, and then puts refcount twice to return the hugepage back to free pool. The second put_page() finally reaches free_huge_page(). Signed-off-by: Naoya Horiguchi Reviewed-by: Aneesh Kumar K.V Cc: Andi Kleen Cc: Tony Luck Cc: Wu Fengguang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/hugetlb.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index e53f39cd67db..22508ef943e6 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3172,7 +3172,13 @@ int dequeue_hwpoisoned_huge_page(struct page *hpage) spin_lock(&hugetlb_lock); if (is_hugepage_on_freelist(hpage)) { - list_del(&hpage->lru); + /* + * Hwpoisoned hugepage isn't linked to activelist or freelist, + * but dangling hpage->lru can trigger list-debug warnings + * (this happens when we call unpoison_memory() on it), + * so let it point to itself with list_del_init(). + */ + list_del_init(&hpage->lru); set_page_refcounted(hpage); h->free_huge_pages--; h->free_huge_pages_node[nid]--; -- 2.20.1