From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 7E1C76B00A1 for ; Mon, 19 Jan 2009 04:51:04 -0500 (EST) Received: from m1.gw.fujitsu.co.jp ([10.0.50.71]) by fgwmail7.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n0J9p26L002342 for (envelope-from kamezawa.hiroyu@jp.fujitsu.com); Mon, 19 Jan 2009 18:51:02 +0900 Received: from smail (m1 [127.0.0.1]) by outgoing.m1.gw.fujitsu.co.jp (Postfix) with ESMTP id C7BF845DD72 for ; Mon, 19 Jan 2009 18:51:01 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by m1.gw.fujitsu.co.jp (Postfix) with ESMTP id A823145DD6F for ; Mon, 19 Jan 2009 18:51:01 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 94D9B1DB803A for ; Mon, 19 Jan 2009 18:51:01 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 45E291DB803C for ; Mon, 19 Jan 2009 18:51:01 +0900 (JST) Date: Mon, 19 Jan 2009 18:49:57 +0900 From: KAMEZAWA Hiroyuki Subject: Re: [memcg BUG] NULL pointer dereference wheng rmdir Message-Id: <20090119184957.91cda7ad.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <49744BC8.2040500@cn.fujitsu.com> References: <49744499.2040101@cn.fujitsu.com> <20090119183341.9418c6de.kamezawa.hiroyu@jp.fujitsu.com> <49744BC8.2040500@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Li Zefan Cc: Balbir Singh , Daisuke Nishimura , "linux-mm@kvack.org" List-ID: On Mon, 19 Jan 2009 17:45:44 +0800 Li Zefan wrote: > KAMEZAWA Hiroyuki wrote: > > On Mon, 19 Jan 2009 17:15:05 +0800 > > Li Zefan wrote: > > > >> note: rmdir[11520] exited with preempt_count 1 > >> =========================================================================== > >> > >> > >> And I've confirmed it's because (zone == NULL) in mem_cgroup_force_empty_list(): > >> > >> > > Hmm, curious. it will be > > > > == > > for_each_node_state(nid, N_POSSIBLE) > > for (zid = 0; zid < MAX_NR_ZONES; zid++) > > zone = &NODE_DATA(nid)->node_zones[zid]; > > > > == > > > > And, from this message, > > > > Unable to handle kernel NULL pointer dereference (address 0000000000002680) > > > > NODE_DATA(nid) seems to be NULL. > > > > Hmm...could you try this ? Thank you for nice test, very helpful. > > The patch fixes the bug. :) > > Tested-by: Li Zefan > Thx, I'll forward to Andrew Morton. -Kame > > -Kame > > == > > From: KAMEZAWA Hiroyuki > > > > N_POSSIBLE doesn't means there is memory...and force_empty can > > visit invalud node which have no pgdat. > > > > To visit all valid nodes, N_HIGH_MEMRY should be used. > > > > Reporetd-by: Li Zefan > > Signed-off-by: KAMEZAWA Hiroyuki > > > > --- > > mm/memcontrol.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > Index: mmotm-2.6.29-Jan16/mm/memcontrol.c > > =================================================================== > > --- mmotm-2.6.29-Jan16.orig/mm/memcontrol.c > > +++ mmotm-2.6.29-Jan16/mm/memcontrol.c > > @@ -1724,7 +1724,7 @@ move_account: > > /* This is for making all *used* pages to be on LRU. */ > > lru_add_drain_all(); > > ret = 0; > > - for_each_node_state(node, N_POSSIBLE) { > > + for_each_node_state(node, N_HIGH_MEMORY) { > > for (zid = 0; !ret && zid < MAX_NR_ZONES; zid++) { > > enum lru_list l; > > for_each_lru(l) { > > > > > > > -- 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/ . Don't email: email@kvack.org