From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758238Ab3JKPqg (ORCPT ); Fri, 11 Oct 2013 11:46:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37479 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753206Ab3JKPqf (ORCPT ); Fri, 11 Oct 2013 11:46:35 -0400 Date: Fri, 11 Oct 2013 11:44:50 -0400 From: Vivek Goyal To: Matthew Garrett Cc: Daniel Kiper , ebiederm@xmission.com, hbabu@us.ibm.com, hpa@linux.intel.com, keescook@chromium.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, david.vrabel@citrix.com, jbeulich@suse.com, keir@xen.org, xen-devel@lists.xen.org Subject: Re: kexec: Clearing registers just before jumping into purgatory Message-ID: <20131011154450.GB2772@redhat.com> References: <20131011092837.GZ3626@debian70-amd64.local.net-space.pl> <877gdkce6s.fsf@tw-ebiederman.twitter.com> <20131011110455.GA3626@debian70-amd64.local.net-space.pl> <20131011125206.GA2772@redhat.com> <20131011153727.GA30181@srcf.ucam.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20131011153727.GA30181@srcf.ucam.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 11, 2013 at 04:37:27PM +0100, Matthew Garrett wrote: > On Fri, Oct 11, 2013 at 08:52:06AM -0400, Vivek Goyal wrote: > > On Fri, Oct 11, 2013 at 01:04:55PM +0200, Daniel Kiper wrote: > > > > [..] > > > > In theory you can swap between to kernels with the preserve_context > > > > case. Technically I like the ability but I don't know that it has ever > > > > achieved much uptake. > > > > > > I think that this is nice idea too. However, I have not seen its usage in real. > > > Even once there was an idea to remove that stuff from Linux Kernel. > > > > I have not seen anybody using it. I don't even know if it works or not. > > It works. I'm using it. Hi Matthew, Just Curious. How is it useful. IOW, what's your use case of booting a new kernel and then jumping back. Thanks Vivek