Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758235AbXKCEDU (ORCPT ); Sat, 3 Nov 2007 00:03:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751919AbXKCEDN (ORCPT ); Sat, 3 Nov 2007 00:03:13 -0400 Received: from rwcrmhc12.comcast.net ([204.127.192.82]:45617 "EHLO rwcrmhc12.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751209AbXKCEDM (ORCPT ); Sat, 3 Nov 2007 00:03:12 -0400 Subject: Re: [patch] PID namespace design bug, workaround From: Nicholas Miell To: Linus Torvalds Cc: Dave Hansen , Andrew Morton , Pavel Emelyanov , Ulrich Drepper , Ingo Molnar , linux-kernel@vger.kernel.org, "Dinakar Guniguntala [imap]" , Sripathi Kodi In-Reply-To: References: <20071101144307.GA29566@elte.hu> <4729E7E4.8070208@openvz.org> <4729E936.4040400@redhat.com> <4729EB3C.9050102@openvz.org> <472A6D91.1020300@redhat.com> <472AD7D6.80900@openvz.org> <20071102010419.23f3db5c.akpm@linux-foundation.org> <1194024622.6271.108.camel@localhost> Content-Type: text/plain Date: Fri, 02 Nov 2007 21:02:59 -0700 Message-Id: <1194062579.3736.4.camel@entropy> Mime-Version: 1.0 X-Mailer: Evolution 2.10.3 (2.10.3-2.fc7.0.njm.1) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1045 Lines: 28 On Fri, 2007-11-02 at 10:39 -0700, Linus Torvalds wrote: > > On Fri, 2 Nov 2007, Dave Hansen wrote: > > > > There are certainly more of these, but here is one In the futex > > userspace address, we install the current pid's vnr into a userspace > > address. > > Now, realistically, why not just say "you can't use these things across > namespaces"? Does anybody really care? After all, somebody who screws this > up only screws himself, not anybody else. > > Linus Accessing the same robust futex from different PID namespaces on the same machine via a shared file mapping is logically equivalent to accessing the same robust futex from different machines via a shared filesystem and there's no reason to expect either operation to work correctly. -- Nicholas Miell - 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/