From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id A7076900194 for ; Wed, 22 Jun 2011 21:13:16 -0400 (EDT) Received: from wpaz37.hot.corp.google.com (wpaz37.hot.corp.google.com [172.24.198.101]) by smtp-out.google.com with ESMTP id p5N1D9aR013275 for ; Wed, 22 Jun 2011 18:13:09 -0700 Received: from pwi4 (pwi4.prod.google.com [10.241.219.4]) by wpaz37.hot.corp.google.com with ESMTP id p5N1Bk0K031727 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Wed, 22 Jun 2011 18:13:07 -0700 Received: by pwi4 with SMTP id 4so999103pwi.29 for ; Wed, 22 Jun 2011 18:13:05 -0700 (PDT) Date: Wed, 22 Jun 2011 18:13:04 -0700 (PDT) From: David Rientjes Subject: [patch 2/2] mm, hotplug: protect zonelist building with zonelists_mutex In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Linus Torvalds Cc: KAMEZAWA Hiroyuki , KOSAKI Motohiro , Mel Gorman , linux-kernel@vger.kernel.org, linux-mm@kvack.org 959ecc48fc75 ("mm/memory_hotplug.c: fix building of node hotplug zonelist") does not protect the build_all_zonelists() call with zonelists_mutex as needed. This can lead to races in constructing zonelist ordering if a concurrent build is underway. Protecting this with lock_memory_hotplug() is insufficient since zonelists can be rebuild though sysfs as well. Signed-off-by: David Rientjes --- mm/memory_hotplug.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -498,7 +498,9 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start) * The node we allocated has no zone fallback lists. For avoiding * to access not-initialized zonelist, build here. */ + mutex_lock(&zonelists_mutex); build_all_zonelists(NULL); + mutex_unlock(&zonelists_mutex); return pgdat; } -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org