From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934541Ab3BTJiK (ORCPT ); Wed, 20 Feb 2013 04:38:10 -0500 Received: from miso.sublimeip.com ([203.12.5.51]:20106 "EHLO miso.sublimeip.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932714Ab3BTJiE (ORCPT ); Wed, 20 Feb 2013 04:38:04 -0500 Subject: Re: prctl(PR_SET_MM) To: gorcunov@openvz.org (Cyrill Gorcunov) Date: Wed, 20 Feb 2013 20:38:01 +1100 (EST) Cc: rostedt@goodmis.org (Steven Rostedt), u3557@dialix.com.au, oleg@redhat.com (Oleg Nesterov), palves@redhat.com (Pedro Alves), dvlasenk@redhat.com (Denys Vlasenko), jan.kratochvil@redhat.com (Jan Kratochvil), xemul@parallels.com (Pavel Emelyanov), fweisbec@gmail.com (Frederic Weisbecker), mingo@redhat.com (Ingo Molnar), a.p.zijlstra@chello.nl (Peter Zijlstra), linux-kernel@vger.kernel.org Reply-To: u3557@dialix.com.au In-Reply-To: <20130220083958.GS20312@moon> X-Mailer: ELM [version 2.5 PL8] MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-Id: <20130220093801.2EE67592064@miso.sublimeip.com> From: u3557@miso.sublimeip.com (Amnon Shiloh) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Cyrill, Cyrill Gorcunov wrote: > On Tue, Feb 19, 2013 at 05:25:31PM +1100, Amnon Shiloh wrote: > > > > To reconstruct Linux process(es), one must be able to restore all their > > memory contents, states and registers to their original and consistent > > values. > > I personally don't mind if this come become y by default, because it will > work for us. I don't mind either, to say the least, to have CONFIG_CHECKPOINT_RESTORE have a "default y" in "init/Kconfig" - that would solve my problem and make me happy, as well as your group and others, but we are told here that Linus has a policy vetoing such changes and I don't believe either of us can make him change his mind. As such, we must look at other options, such as having the code in "kernel/sys.c" out in the open, not enclosed by any #ifdef's altogether - surely you would like that! > Still I guess if you need to reconstruct Linux process(es) > plain prctl extension is not enough, you still need a functionality which > is enclosed in config-checkpoint-restore (say /proc/pid/map_files, kcmp), > no? My process-migration package only reconstructs Linux processes partially: as it's a bit different than any classical checkpoint-restore, the critical code in "kernel/sys.c" is all I need at the moment (from within CONFIG_CHECKPOINT_RESTORE). I do appreciate that anyone attempting to perform complete, classical, checkpoint-restore operations, needs more than that. Best Regards, Amnon.