From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161042AbXCNKPi (ORCPT ); Wed, 14 Mar 2007 06:15:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161052AbXCNKPi (ORCPT ); Wed, 14 Mar 2007 06:15:38 -0400 Received: from calculon.skynet.ie ([193.1.99.88]:34060 "EHLO calculon.skynet.ie" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161042AbXCNKPh (ORCPT ); Wed, 14 Mar 2007 06:15:37 -0400 Date: Wed, 14 Mar 2007 09:44:54 +0000 To: Bjorn Helgaas Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: 2.6.21-rc3-mm2 (oops in move_freepages) Message-ID: <20070314094454.GA1652@skynet.ie> References: <20070307201915.4d579113.akpm@linux-foundation.org> <200703132152.10136.bjorn.helgaas@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <200703132152.10136.bjorn.helgaas@hp.com> User-Agent: Mutt/1.5.9i From: mel@skynet.ie (Mel Gorman) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On (13/03/07 21:52), Bjorn Helgaas didst pronounce: > FYI, I'm seeing the following oops with 2.6.21-rc3-mm1 (and -mm2) > on the HP rx2600 and an Intel Tiger (both ia64 boxes). > > I haven't investigated this other than to determine that it > does not occur with 2.6.21-rc3 or 2.6.20-rc3-mm1, and the > instruction at move_freepages+0x10 is a load of the value > pointed to by the third argument (end_page). > Please try the following patch from Yasunori Goto. >>From y-goto@jp.fujitsu.com Thu Mar 8 08:00:15 2007 Date: Thu, 08 Mar 2007 16:39:43 +0900 From: Yasunori Goto To: Andrew Morton Cc: linux-kernel@vger.kernel.org, Mel Gorman Subject: [PATCH] fix BUG_ON check at move_freepages() (Re: 2.6.21-rc3-mm2) Hello. The BUG_ON() check at move_freepages() is wrong. Its end_page is start_page + MAX_ORDER_NR_PAGES. So, it can be next zone. BUG_ON() should check "end_page - 1". This is fix of 2.6.21-rc3-mm2 for it. Signed-off-by: Yasunori Goto --- mm/page_alloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: current_test/mm/page_alloc.c =================================================================== --- current_test.orig/mm/page_alloc.c 2007-03-08 15:44:10.000000000 +0900 +++ current_test/mm/page_alloc.c 2007-03-08 16:17:29.000000000 +0900 @@ -707,7 +707,7 @@ int move_freepages(struct zone *zone, unsigned long order; int blocks_moved = 0; - BUG_ON(page_zone(start_page) != page_zone(end_page)); + BUG_ON(page_zone(start_page) != page_zone(end_page - 1)); for (page = start_page; page < end_page;) { if (!PageBuddy(page)) {