Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754309Ab0GNBrr (ORCPT ); Tue, 13 Jul 2010 21:47:47 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:51925 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751137Ab0GNBrp (ORCPT ); Tue, 13 Jul 2010 21:47:45 -0400 To: Andrew Morton Cc: Pavel Emelyanov , Oleg Nesterov , linux-kernel@vger.kernel.org, Linux Containers , Sukadev Bhattiprolu Subject: Re: [PATCH] pidns: Fix wait for zombies to be reaped in zap_pid_ns_processes References: <20100625212758.GA30474@redhat.com> <20100625220713.GA31123@us.ibm.com> <20100709121425.GB18586@hawkmoon.kerlabs.com> <20100709141324.GC18586@hawkmoon.kerlabs.com> <20100711141406.GD18586@hawkmoon.kerlabs.com> <20100713214234.GA21042@hawkmoon.kerlabs.com> From: ebiederm@xmission.com (Eric W. Biederman) Date: Tue, 13 Jul 2010 18:47:38 -0700 In-Reply-To: <20100713214234.GA21042@hawkmoon.kerlabs.com> (Louis Rilling's message of "Tue\, 13 Jul 2010 23\:42\:35 +0200") Message-ID: User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in02.mta.xmission.com;;;ip=67.188.4.80;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 67.188.4.80 X-SA-Exim-Mail-From: ebiederm@xmission.com X-SA-Exim-Scanned: No (on in02.mta.xmission.com); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1284 Lines: 31 Louis Rilling writes: > This patch looks like it is working (only a small RCU issue shown below). I > couldn't try it yet though. It certainly worked in my testing. > I must admit that I am using a similar back-off solution in Kerrighed (not to > solve the issue of proc_flush_task(), but for one of the reasons that you stated > above: we want to be sure that all tasks of the namespace have been reaped), but > I considered it too ugly to propose it for Linux ;) Well sometimes you have to go with what works. Thanks for spotting those issue with my patch. I guess it needs one more pass before I can call it done. > That said, this is probably the least intrusive solution we have seen yet. Thanks for the review. The bug where processes can escape a pid namespace is really the reason I did it this way. I also have the patches needed to cleanly fix the pid namespace ref counting. (Hopefully I can get them posted soon). So if there was just the ref counting bug I would drop this patch. Eric -- 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/