From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id 16B366B00D7 for ; Wed, 26 Aug 2009 05:36:28 -0400 (EDT) Received: from m2.gw.fujitsu.co.jp ([10.0.50.72]) by fgwmail6.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id n7Q9aRlb006656 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Wed, 26 Aug 2009 18:36:27 +0900 Received: from smail (m2 [127.0.0.1]) by outgoing.m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 2789445DE55 for ; Wed, 26 Aug 2009 18:36:27 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (s2.gw.fujitsu.co.jp [10.0.50.92]) by m2.gw.fujitsu.co.jp (Postfix) with ESMTP id 0962845DE4F for ; Wed, 26 Aug 2009 18:36:27 +0900 (JST) Received: from s2.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id E763AE38002 for ; Wed, 26 Aug 2009 18:36:26 +0900 (JST) Received: from m106.s.css.fujitsu.com (m106.s.css.fujitsu.com [10.249.87.106]) by s2.gw.fujitsu.co.jp (Postfix) with ESMTP id A16BD1DB803A for ; Wed, 26 Aug 2009 18:36:26 +0900 (JST) From: KOSAKI Motohiro Subject: [mmotm][PATCH 3/4] oom: oom_kill doesn't kill vfork parent(or child) In-Reply-To: <20090826182634.3968.A69D9226@jp.fujitsu.com> References: <20090826182634.3968.A69D9226@jp.fujitsu.com> Message-Id: <20090826183529.3971.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Wed, 26 Aug 2009 18:36:25 +0900 (JST) Sender: owner-linux-mm@kvack.org To: LKML Cc: kosaki.motohiro@jp.fujitsu.com, linux-mm , Andrew Morton , Paul Menage , David Rientjes , KAMEZAWA Hiroyuki , Oleg Nesterov List-ID: Current oom_kill doesn't only kill the victim process, but also kill all thas shread the same mm. it mean vfork parent will be killed. This is definitely incorrect. another process have another oom_adj. we shouldn't ignore their oom_adj (it might have OOM_DISABLE). following caller hit the minefield. --------------------------------------- switch (constraint) { case CONSTRAINT_MEMORY_POLICY: oom_kill_process(current, gfp_mask, order, 0, NULL, "No available memory (MPOL_BIND)"); break; Note: force_sig(SIGKILL) send SIGKILL to all thread in the process. We don't need to care multi thread in here. Cc: Paul Menage Cc: David Rientjes Cc: KAMEZAWA Hiroyuki Cc: Andrew Morton , Signed-off-by: KOSAKI Motohiro --- mm/oom_kill.c | 17 +---------------- 1 files changed, 1 insertions(+), 16 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 26725bc..f8fa81e 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -373,11 +373,6 @@ static void __oom_kill_task(struct task_struct *p, int verbose) static int oom_kill_task(struct task_struct *p) { - struct mm_struct *mm; - struct task_struct *g, *q; - - mm = p->mm; - /* WARNING: mm may not be dereferenced since we did not obtain its * value from get_task_mm(p). This is OK since all we need to do is * compare mm to q->mm below. @@ -386,21 +381,11 @@ static int oom_kill_task(struct task_struct *p) * change to NULL at any time since we do not hold task_lock(p). * However, this is of no concern to us. */ - if (!mm || p->signal->oom_adj == OOM_DISABLE) + if (!p->mm || p->signal->oom_adj == OOM_DISABLE) return 1; __oom_kill_task(p, 1); - /* - * kill all processes that share the ->mm (i.e. all threads), - * but are in a different thread group. Don't let them have access - * to memory reserves though, otherwise we might deplete all memory. - */ - do_each_thread(g, q) { - if (q->mm == mm && !same_thread_group(q, p)) - force_sig(SIGKILL, q); - } while_each_thread(g, q); - return 0; } -- 1.6.2.5 -- 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