From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756085AbYICRjf (ORCPT ); Wed, 3 Sep 2008 13:39:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756766AbYICRin (ORCPT ); Wed, 3 Sep 2008 13:38:43 -0400 Received: from mx2.suse.de ([195.135.220.15]:56390 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756758AbYICRim (ORCPT ); Wed, 3 Sep 2008 13:38:42 -0400 Date: Wed, 3 Sep 2008 10:25:57 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, jejb@kernel.org Cc: Justin Forbes , Zwane Mwaikambo , "Theodore Ts'o" , Randy Dunlap , Dave Jones , Chuck Wolber , Chris Wedgwood , Michael Krufky , Chuck Ebbert , Domenico Andreoli , Willy Tarreau , Rodrigo Rubira Branco , Jake Edge , Eugene Teo , torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Adam Litke , Mel Gorman , Dave Hansen , Nishanth Aravamudan , Andy Whitcroft Subject: [patch 19/42] mm: make setup_zone_migrate_reserve() aware of overlapping nodes Message-ID: <20080903172557.GT7731@suse.de> References: <20080903171927.534216229@mini.kroah.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="mm-make-setup_zone_migrate_reserve-aware-of-overlapping-nodes.patch" In-Reply-To: <20080903172447.GA7731@suse.de> User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.26-stable review patch. If anyone has any objections, please let us know. ------------------ From: Adam Litke commit 344c790e3821dac37eb742ddd0b611a300f78b9a upstream I have gotten to the root cause of the hugetlb badness I reported back on August 15th. My system has the following memory topology (note the overlapping node): Node 0 Memory: 0x8000000-0x44000000 Node 1 Memory: 0x0-0x8000000 0x44000000-0x80000000 setup_zone_migrate_reserve() scans the address range 0x0-0x8000000 looking for a pageblock to move onto the MIGRATE_RESERVE list. Finding no candidates, it happily continues the scan into 0x8000000-0x44000000. When a pageblock is found, the pages are moved to the MIGRATE_RESERVE list on the wrong zone. Oops. setup_zone_migrate_reserve() should skip pageblocks in overlapping nodes. Signed-off-by: Adam Litke Acked-by: Mel Gorman Cc: Dave Hansen Cc: Nishanth Aravamudan Cc: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/page_alloc.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -693,6 +693,9 @@ int move_freepages(struct zone *zone, #endif for (page = start_page; page <= end_page;) { + /* Make sure we are not inadvertently changing nodes */ + VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone)); + if (!pfn_valid_within(page_to_pfn(page))) { page++; continue; @@ -2475,6 +2478,10 @@ static void setup_zone_migrate_reserve(s continue; page = pfn_to_page(pfn); + /* Watch out for overlapping nodes */ + if (page_to_nid(page) != zone_to_nid(zone)) + continue; + /* Blocks with reserved pages will never free, skip them. */ if (PageReserved(page)) continue; --