From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759016Ab3K1O6G (ORCPT ); Thu, 28 Nov 2013 09:58:06 -0500 Received: from merlin.infradead.org ([205.233.59.134]:51752 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758240Ab3K1O6C (ORCPT ); Thu, 28 Nov 2013 09:58:02 -0500 Date: Thu, 28 Nov 2013 15:57:55 +0100 From: Peter Zijlstra To: Tejun Heo Cc: Oleg Nesterov , zhang.yi20@zte.com.cn, lkml , Tetsuo Handa , Ingo Molnar Subject: Re: [PATCH]: exec: avoid propagating PF_NO_SETAFFINITY into userspace child Message-ID: <20131128145755.GY10022@twins.programming.kicks-ass.net> References: <20131127183117.GB13098@mtj.dyndns.org> <20131128091358.GH10022@twins.programming.kicks-ass.net> <20131128114542.GA3826@redhat.com> <20131128121748.GN10022@twins.programming.kicks-ass.net> <20131128133152.GA821@redhat.com> <20131128133947.GR10022@twins.programming.kicks-ass.net> <20131128141329.GB3925@htj.dyndns.org> <20131128143145.GT10022@twins.programming.kicks-ass.net> <20131128144359.GL3694@twins.programming.kicks-ass.net> <20131128145325.GG3925@htj.dyndns.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131128145325.GG3925@htj.dyndns.org> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Nov 28, 2013 at 09:53:25AM -0500, Tejun Heo wrote: > On Thu, Nov 28, 2013 at 03:43:59PM +0100, Peter Zijlstra wrote: > > On Thu, Nov 28, 2013 at 03:31:45PM +0100, Peter Zijlstra wrote: > > > Sure, we absolutely must set it for per-cpu workqueues (and their > > > workers) otherwise we cannot guarantee correctness. Same for per-node if > > > we have that. > > > > On that, the per-node thing is debatable. There's no correctness issues > > with per-node stuff as we have with per-cpu storage. > > > > And if there's no correctness implications we should not force things. > > That's true iff you confine the "correctness" to not crashing. That's > an extremely narrow definition tho and most will argue against that. Do you have a better definition that doesn't get in the way of people wanting to do actual work? So far I just see you breaking existing setups because you don't want to support things that work perfectly well.