From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757471AbXLUI6Q (ORCPT ); Fri, 21 Dec 2007 03:58:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753823AbXLUI6B (ORCPT ); Fri, 21 Dec 2007 03:58:01 -0500 Received: from mga01.intel.com ([192.55.52.88]:40540 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753622AbXLUI6A (ORCPT ); Fri, 21 Dec 2007 03:58:00 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.24,193,1196668800"; d="scan'208";a="453009917" Subject: Re: [PATCH 0/3 -mm] kexec jump -v8 From: "Huang, Ying" To: nigel@nigel.suspend2.net Cc: Kexec Mailing List , linux-kernel@vger.kernel.org, "Rafael J. Wysocki" , "Eric W. Biederman" , Pavel Machek , Andrew Morton , linux-pm@lists.linux-foundation.org In-Reply-To: <476B7ACF.8020602@nigel.suspend2.net> References: <1198222399.1965.15.camel@caritas-dev.intel.com> <476B7ACF.8020602@nigel.suspend2.net> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Fri, 21 Dec 2007 16:53:27 +0800 Message-Id: <1198227207.25346.11.camel@caritas-dev.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.10.3 X-OriginalArrivalTime: 21 Dec 2007 08:53:24.0836 (UTC) FILETIME=[F249EA40:01C843AE] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2007-12-21 at 19:35 +1100, Nigel Cunningham wrote: > Hi. > > Huang, Ying wrote: > > This patchset provides an enhancement to kexec/kdump. It implements > > the following features: > > > > - Backup/restore memory used both by the original kernel and the > > kexeced kernel. > > Why the kexeced kernel as well? The memory range used by kexeced kernel is also the usable memory range in original kernel. Maybe should be: backup/restore memory used by both the original kernel and the kexeced kernel. My English is poor. > [...] > > > The features of this patchset can be used as follow: > > > > - Kernel/system debug through making system snapshot. You can make > > system snapshot, jump back, do some thing and make another system > > snapshot. > > Are you somehow recording all the filesystem changes after the first > snapshot? If not, this is pointless (you'll end up with filesystem > corruption). This snapshot is not used for restore/resume. It is just used for debugging. You can check the system state with these snapshots. So I think it is useful even without recording filesystem changes. > [...] > > > - Cooperative multi-kernel/system. With kexec jump, you can switch > > between several kernels/systems quickly without boot process except > > the first time. This appears like swap a whole kernel/system out/in. > > How is this useful to the end user? I am not sure how useful is this. Maybe I can run a Redhat and a Debian on my machine and switch between them. Best Regards, Huang Ying