From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id C62636006F7 for ; Thu, 1 Jul 2010 09:38:56 -0400 (EDT) Received: by pxi17 with SMTP id 17so934117pxi.14 for ; Thu, 01 Jul 2010 06:38:54 -0700 (PDT) Date: Thu, 1 Jul 2010 22:38:46 +0900 From: Minchan Kim Subject: Re: [PATCH 02/11] oom: oom_kill_process() doesn't select kthread child Message-ID: <20100701133846.GA16383@barrios-desktop> References: <20100630182715.AA4B.A69D9226@jp.fujitsu.com> <20100630135503.GA15644@barrios-desktop> <20100701085011.DA13.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100701085011.DA13.A69D9226@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: LKML , linux-mm , Andrew Morton , David Rientjes , KAMEZAWA Hiroyuki List-ID: On Thu, Jul 01, 2010 at 09:07:02AM +0900, KOSAKI Motohiro wrote: > > On Wed, Jun 30, 2010 at 06:27:52PM +0900, KOSAKI Motohiro wrote: > > > Now, select_bad_process() have PF_KTHREAD check, but oom_kill_process > > > doesn't. It mean oom_kill_process() may choose wrong task, especially, > > > when the child are using use_mm(). > > > > Is it possible child is kthread even though parent isn't kthread? > > Usually unhappen. but crappy driver can do any strange thing freely. > As I said, oom code should have conservative assumption as far as possible. Okay. You change the check with oom_unkillable_task at last. The oom_unkillable_task is generic function so that the kthread check in oom_kill_process is tivial, I think. Reviewed-by: Minchan Kim > > > -- Kind regards, Minchan Kim -- 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