From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754806Ab3ADOiu (ORCPT ); Fri, 4 Jan 2013 09:38:50 -0500 Received: from smtp.citrix.com ([66.165.176.89]:37062 "EHLO SMTP.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754738Ab3ADOis (ORCPT ); Fri, 4 Jan 2013 09:38:48 -0500 X-IronPort-AV: E=Sophos;i="4.84,409,1355097600"; d="scan'208";a="2701590" Message-ID: <50E6E974.5090805@citrix.com> Date: Fri, 4 Jan 2013 14:38:44 +0000 From: David Vrabel User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20120428 Iceowl/1.0b1 Icedove/3.0.11 MIME-Version: 1.0 To: Daniel Kiper CC: Andrew Cooper , "xen-devel@lists.xensource.com" , "konrad.wilk@oracle.com" , "maxim.uvarov@oracle.com" , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "mingo@redhat.com" , "Eric W. Biederman" , "jbeulich@suse.com" , "H. Peter Anvin" , "tglx@linutronix.de" , "vgoyal@redhat.com" Subject: Re: [Xen-devel] [PATCH v3 00/11] xen: Initial kexec/kdump implementation References: <1356574740-6806-1-git-send-email-daniel.kiper@oracle.com> <50DBC856.6030208@zytor.com> <791b4922-078f-4adc-b3f3-0651f2266147@email.android.com> <50DC58C4.3000307@citrix.com> <874nj7qsor.fsf@xmission.com> <50E41973.9050705@citrix.com> <20130104142257.GC3346@host-192-168-1-59.local.net-space.pl> In-Reply-To: <20130104142257.GC3346@host-192-168-1-59.local.net-space.pl> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.2.76] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/01/13 14:22, Daniel Kiper wrote: > On Wed, Jan 02, 2013 at 11:26:43AM +0000, Andrew Cooper wrote: >> On 27/12/12 18:02, Eric W. Biederman wrote: >>> Andrew Cooper writes: >>> >>>> On 27/12/2012 07:53, Eric W. Biederman wrote: >>>>> The syscall ABI still has the wrong semantics. >>>>> >>>>> Aka totally unmaintainable and umergeable. >>>>> >>>>> The concept of domU support is also strange. What does domU support even mean, when the dom0 support is loading a kernel to pick up Xen when Xen falls over. >>>> There are two requirements pulling at this patch series, but I agree >>>> that we need to clarify them. >>> It probably make sense to split them apart a little even. >>> >>> >> >> Thinking about this split, there might be a way to simply it even more. >> >> /sbin/kexec can load the "Xen" crash kernel itself by issuing >> hypercalls using /dev/xen/privcmd. This would remove the need for >> the dom0 kernel to distinguish between loading a crash kernel for >> itself and loading a kernel for Xen. >> >> Or is this just a silly idea complicating the matter? > > This is impossible with current Xen kexec/kdump interface. > It should be changed to do that. However, I suppose that > Xen community would not be interested in such changes. I don't see why the hypercall ABI cannot be extended with new sub-ops that do the right thing -- the existing ABI is a bit weird. I plan to start prototyping something shortly (hopefully next week) for the Xen kexec case. David