Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964912AbWART3F (ORCPT ); Wed, 18 Jan 2006 14:29:05 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964916AbWART3F (ORCPT ); Wed, 18 Jan 2006 14:29:05 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:42213 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S964912AbWART3E (ORCPT ); Wed, 18 Jan 2006 14:29:04 -0500 Subject: Re: RFC [patch 00/34] PID Virtualization Overview From: Arjan van de Ven To: Dave Hansen Cc: Alan Cox , Suleiman Souhlal , Serge Hallyn , linux-kernel@vger.kernel.org, Hubertus Franke , Cedric Le Goater In-Reply-To: <1137610912.24321.50.camel@localhost.localdomain> References: <20060117143258.150807000@sergelap> <43CD18FF.4070006@FreeBSD.org> <1137517698.8091.29.camel@localhost.localdomain> <43CD32F0.9010506@FreeBSD.org> <1137521557.5526.18.camel@localhost.localdomain> <1137522550.14135.76.camel@localhost.localdomain> <1137610912.24321.50.camel@localhost.localdomain> Content-Type: text/plain Date: Wed, 18 Jan 2006 20:28:56 +0100 Message-Id: <1137612537.3005.116.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.2.3 (2.2.3-2.fc4) Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1336 Lines: 28 On Wed, 2006-01-18 at 11:01 -0800, Dave Hansen wrote: > On Tue, 2006-01-17 at 18:29 +0000, Alan Cox wrote: > > On Maw, 2006-01-17 at 10:12 -0800, Dave Hansen wrote: > > > You do assign new pids, at least as far as the kernel is concerned. > > > However, any processes that continue to run would get confused if their > > > pid changed. You have to make sure that the tasks have a _consistent_ > > > view of which process is which pid. > > > > Don't reassign the pid at all. Keep task->container and do the job > > explicitly. Most task searches for a pid are abstracted already and most > > users of ->pid who try and use it for comparing two tasks for equality > > or for keeping a task reference are already terminally racey and want > > fixing anyway. > > Other than searches, there appear to be quite a number of drivers an > subsystems that like to print out pids. I can't find any cases yet > where these are integral to functionality, but I wonder what approach we > should take. those should obviously print out the REAL pid, not the application pid ... so no changes needed. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/