From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755793Ab2GaFGg (ORCPT ); Tue, 31 Jul 2012 01:06:36 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48523 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755316Ab2GaEuE (ORCPT ); Tue, 31 Jul 2012 00:50:04 -0400 Message-Id: <20120731044313.816574497@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Tue, 31 Jul 2012 05:43:26 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Konstantin Khlebnikov , Mel Gorman , David Rientjes Subject: [ 16/73] mm/hugetlb: fix warning in alloc_huge_page/dequeue_huge_page_vma In-Reply-To: <20120731044310.013763753@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:21c:bfff:fe03:f805 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Konstantin Khlebnikov commit b1c12cbcd0a02527c180a862e8971e249d3b347d upstream. Stable note: Not tracked in Bugzilla. [get|put]_mems_allowed() is extremely expensive and severely impacted page allocator performance. This is part of a series of patches that reduce page allocator overhead. Fix a gcc warning (and bug?) introduced in cc9a6c877 ("cpuset: mm: reduce large amounts of memory barrier related damage v3") Local variable "page" can be uninitialized if the nodemask from vma policy does not intersects with nodemask from cpuset. Even if it doesn't happens it is better to initialize this variable explicitly than to introduce a kernel oops in a weird corner case. mm/hugetlb.c: In function `alloc_huge_page': mm/hugetlb.c:1135:5: warning: `page' may be used uninitialized in this function Signed-off-by: Konstantin Khlebnikov Acked-by: Mel Gorman Acked-by: David Rientjes Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Mel Gorman Signed-off-by: Ben Hutchings --- mm/hugetlb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index cd65cb1..5a16423 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -532,7 +532,7 @@ static struct page *dequeue_huge_page_vma(struct hstate *h, struct vm_area_struct *vma, unsigned long address, int avoid_reserve) { - struct page *page; + struct page *page = NULL; struct mempolicy *mpol; nodemask_t *nodemask; struct zonelist *zonelist;