From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752119AbXB1LBE (ORCPT ); Wed, 28 Feb 2007 06:01:04 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752125AbXB1LBE (ORCPT ); Wed, 28 Feb 2007 06:01:04 -0500 Received: from mail.screens.ru ([213.234.233.54]:37217 "EHLO mail.screens.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752119AbXB1LBD (ORCPT ); Wed, 28 Feb 2007 06:01:03 -0500 Date: Wed, 28 Feb 2007 14:00:48 +0300 From: Oleg Nesterov To: "Rafael J. Wysocki" Cc: vatsa@in.ibm.com, Aneesh Kumar , LKML , Andrew Morton , Pavel Machek , "Paul E. McKenney" , Gautham R Shenoy Subject: Re: [RFC][PATCH 1/3] Freezer: Fix vfork problem Message-ID: <20070228110048.GA263@tv-sign.ru> References: <200702261139.59130.rjw@sisk.pl> <20070227215314.GA427@tv-sign.ru> <20070228012301.GH29179@in.ibm.com> <200702281157.28381.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200702281157.28381.rjw@sisk.pl> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 02/28, Rafael J. Wysocki wrote: > > On Wednesday, 28 February 2007 02:23, Srivatsa Vaddagiri wrote: > > On Wed, Feb 28, 2007 at 12:53:14AM +0300, Oleg Nesterov wrote: > > > I think it is good. Srivatsa? > > > > Maybe additional comments on why we don't skip vfork kernel tasks may be good. > > Which is because we don't want the kernel threads to be frozen in unexpected > places, so we allow them to block freeze_processes() instead or to set > PF_NOFREEZE? ... and because in fact it won't block freeze_processes(), ____call_usermodehelper (the child) does a minimum before exec/exit, and it can't be frozen until it wakes up the parent. Oleg.