From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756143AbbLBKfy (ORCPT ); Wed, 2 Dec 2015 05:35:54 -0500 Received: from mail-wm0-f54.google.com ([74.125.82.54]:34020 "EHLO mail-wm0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755548AbbLBKfw (ORCPT ); Wed, 2 Dec 2015 05:35:52 -0500 Date: Wed, 2 Dec 2015 11:35:49 +0100 From: Michal Hocko To: chenjie6@huawei.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, David.Woodhouse@intel.com, zhihui.gao@huawei.com, lizefan@huawei.com, akpm@linux-foundation.org, stable@vger.kernel.org Subject: Re: [PATCH] oom kill init lead panic Message-ID: <20151202103549.GB25290@dhcp22.suse.cz> References: <1449037856-23990-1-git-send-email-chenjie6@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1449037856-23990-1-git-send-email-chenjie6@huawei.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed 02-12-15 14:30:56, chenjie6@huawei.com wrote: > From: chenjie > > when oom happened we can see: > Out of memory: Kill process 9134 (init) score 3 or sacrifice child > Killed process 9134 (init) total-vm:1868kB, anon-rss:84kB, file-rss:572kB > Kill process 1 (init) sharing same memory > ... > Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009 > > That's because: > the busybox init will vfork a process,oom_kill_process found > the init not the children,their mm is the same when vfork. It is quite unlikely that killing the task would help to free much memory so if this is really the only oom victim it is to be expected to panic sooner or later but this is in line with oom_unkillable_task() so it makes sense. > Cc: > Signed-off-by: Chen Jie Acked-by: Michal Hocko > > --- > mm/oom_kill.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/mm/oom_kill.c b/mm/oom_kill.c > index d13a339..a0ddebd 100644 > --- a/mm/oom_kill.c > +++ b/mm/oom_kill.c > @@ -608,6 +608,8 @@ void oom_kill_process(struct oom_control *oc, struct task_struct *p, > continue; > if (unlikely(p->flags & PF_KTHREAD)) > continue; > + if (!is_global_init(p)) > + continue; > if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) > continue; > > -- > 1.8.0 > > -- > 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 -- Michal Hocko SUSE Labs