Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758396Ab3FMJ06 (ORCPT ); Thu, 13 Jun 2013 05:26:58 -0400 Received: from relay.parallels.com ([195.214.232.42]:45846 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756151Ab3FMJ04 (ORCPT ); Thu, 13 Jun 2013 05:26:56 -0400 Date: Thu, 13 Jun 2013 13:24:42 +0400 From: Andrew Vagin To: Oleg Nesterov CC: Andrey Vagin , "Eric W. Biederman" , , Andrew Morton , Al Viro , David Howells Subject: Re: [PATCH 1/1] move exit_task_namespaces() outside of exit_notify() Message-ID: <20130613092442.GA32730@paralelels.com> References: <1365794853-23912-1-git-send-email-avagin@openvz.org> <20130413142246.GA864@redhat.com> <20130413155457.GA6533@redhat.com> <20130413155521.GB6533@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="koi8-r" Content-Disposition: inline In-Reply-To: <20130413155521.GB6533@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Originating-IP: [10.30.16.48] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1916 Lines: 53 On Sat, Apr 13, 2013 at 05:55:21PM +0200, Oleg Nesterov wrote: > exit_notify() does exit_task_namespaces() after > forget_original_parent(). This was needed to ensure that ->nsproxy > can't be cleared prematurely, an exiting child we are going to > reparent can do do_notify_parent() and use the parent's (ours) pid_ns. > > However, after 32084504 "pidns: use task_active_pid_ns in > do_notify_parent" ->nsproxy != NULL is no longer needed, we rely > on task_active_pid_ns(). > > Move exit_task_namespaces() from exit_notify() to do_exit(), after > exit_fs() and before exit_task_work(). > > This solves the problem reported by Andrey, free_ipc_ns()->shm_destroy() > does fput() which needs task_work_add(). And this allows us do simplify > exit_notify(), we can avoid unlock/lock(tasklist) and we can change > ->exit_state instead of PF_EXITING in forget_original_parent(). > It looks good for me. kmemleak doesn't report any leaks. CRIU test cases, which use namespaces, work without any errors. Thanks. Acked-by: Andrey Vagin > Reported-by: Andrey Vagin > Signed-off-by: Oleg Nesterov > > --- x/kernel/exit.c > +++ x/kernel/exit.c > @@ -649,7 +649,6 @@ static void exit_notify(struct task_stru > * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) > */ > forget_original_parent(tsk); > - exit_task_namespaces(tsk); > > write_lock_irq(&tasklist_lock); > if (group_dead) > @@ -795,6 +794,7 @@ void do_exit(long code) > exit_shm(tsk); > exit_files(tsk); > exit_fs(tsk); > + exit_task_namespaces(tsk); > exit_task_work(tsk); > check_stack_usage(); > exit_thread(); > -- 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/