Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755183Ab3G2FcZ (ORCPT ); Mon, 29 Jul 2013 01:32:25 -0400 Received: from LGEMRELSE7Q.lge.com ([156.147.1.151]:44032 "EHLO LGEMRELSE7Q.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755108Ab3G2FcV (ORCPT ); Mon, 29 Jul 2013 01:32:21 -0400 X-AuditID: 9c930197-b7bfbae000000e88-09-51f5fe63f6fa From: Joonsoo Kim To: Andrew Morton Cc: Rik van Riel , Mel Gorman , Michal Hocko , "Aneesh Kumar K.V" , KAMEZAWA Hiroyuki , Hugh Dickins , Davidlohr Bueso , David Gibson , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Joonsoo Kim , Wanpeng Li , Naoya Horiguchi , Hillf Danton , Joonsoo Kim Subject: [PATCH 01/18] mm, hugetlb: protect reserved pages when softofflining requests the pages Date: Mon, 29 Jul 2013 14:31:52 +0900 Message-Id: <1375075929-6119-2-git-send-email-iamjoonsoo.kim@lge.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1375075929-6119-1-git-send-email-iamjoonsoo.kim@lge.com> References: <1375075929-6119-1-git-send-email-iamjoonsoo.kim@lge.com> X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1042 Lines: 32 alloc_huge_page_node() use dequeue_huge_page_node() without any validation check, so it can steal reserved page unconditionally. To fix it, check the number of free_huge_page in alloc_huge_page_node(). Signed-off-by: Joonsoo Kim diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 6782b41..d971233 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -935,10 +935,11 @@ static struct page *alloc_buddy_huge_page(struct hstate *h, int nid) */ struct page *alloc_huge_page_node(struct hstate *h, int nid) { - struct page *page; + struct page *page = NULL; spin_lock(&hugetlb_lock); - page = dequeue_huge_page_node(h, nid); + if (h->free_huge_pages - h->resv_huge_pages > 0) + page = dequeue_huge_page_node(h, nid); spin_unlock(&hugetlb_lock); if (!page) -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/