From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751899Ab0C2LsQ (ORCPT ); Mon, 29 Mar 2010 07:48:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:28931 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750925Ab0C2LsP (ORCPT ); Mon, 29 Mar 2010 07:48:15 -0400 Date: Mon, 29 Mar 2010 13:46:30 +0200 From: Oleg Nesterov To: anfei Cc: Andrew Morton , rientjes@google.com, kosaki.motohiro@jp.fujitsu.com, nishimura@mxp.nes.nec.co.jp, kamezawa.hiroyu@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] oom killer: break from infinite loop Message-ID: <20100329114630.GA19277@redhat.com> References: <1269447905-5939-1-git-send-email-anfei.zhou@gmail.com> <20100326150805.f5853d1c.akpm@linux-foundation.org> <20100326223356.GA20833@redhat.com> <20100328145528.GA14622@desktop> <20100328162821.GA16765@redhat.com> <20100329113113.GA11838@desktop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100329113113.GA11838@desktop> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/29, anfei wrote: > > On Sun, Mar 28, 2010 at 06:28:21PM +0200, Oleg Nesterov wrote: > > On 03/28, anfei wrote: > > > > > > Assume thread A and B are in the same group. If A runs into the oom, > > > and selects B as the victim, B won't exit because at least in exit_mm(), > > > it can not get the mm->mmap_sem semaphore which A has already got. > > > > I see. But still I can't understand. To me, the problem is not that > > B can't exit, the problem is that A doesn't know it should exit. All > > If B can exit, its memory will be freed, Which memory? I thought, we are talking about the memory used by ->mm ? Oleg.