From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756826Ab2KWBji (ORCPT ); Thu, 22 Nov 2012 20:39:38 -0500 Received: from terminus.zytor.com ([198.137.202.10]:49904 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756648Ab2KWBjh (ORCPT ); Thu, 22 Nov 2012 20:39:37 -0500 User-Agent: K-9 Mail for Android In-Reply-To: <50AEBF86.50501@citrix.com> References: <1353423893-23125-1-git-send-email-daniel.kiper@oracle.com> <1353423893-23125-2-git-send-email-daniel.kiper@oracle.com> <87lidwtego.fsf@xmission.com> <20121121105221.GA2925@host-192-168-1-59.local.net-space.pl> <87txshx28b.fsf@xmission.com> <50AE6542.3020302@zytor.com> <50AEBF86.50501@citrix.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH v2 01/11] kexec: introduce kexec_ops struct From: "H. Peter Anvin" Date: Thu, 22 Nov 2012 17:38:33 -0800 To: Andrew Cooper CC: "Eric W. Biederman" , Daniel Kiper , "jbeulich@suse.com" , "konrad.wilk@oracle.com" , "mingo@redhat.com" , "tglx@linutronix.de" , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "xen-devel@lists.xensource.com" Message-ID: <18e831d4-910d-4f58-8911-1398b96e3a47@email.android.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I still don't really get why it can't be isolated from dom0, which would make more sense to me, even for a Xen crash. Andrew Cooper wrote: >On 22/11/2012 17:47, H. Peter Anvin wrote: >> The other thing that should be considered here is how utterly >> preposterous the notion of doing in-guest crash dumping is in a >system >> that contains a hypervisor. The reason for kdump is that on bare >metal >> there are no other options, but in a hypervisor system the right >thing >> should be for the hypervisor to do the dump (possibly spawning a >clean >> I/O domain if the I/O domain is necessary to access the media.) >> >> There is absolutely no reason to have a crashkernel sitting around in > >> each guest, consuming memory, and possibly get corrupt. >> >> -hpa >> > >(Your reply to my email which I can see on the xen devel archive >appears >to have gotten lost somewhere inside the citrix email system, so >apologies for replying out of order) > >The kdump kernel loaded by dom0 is for when Xen crashes, not for when >dom0 crashes (although a dom0 crash does admittedly lead to a Xen >crash) > >There is no possible way it could be a separate domain; Xen completely >ceases to function as soon as jumps to the entry point of the kdump >image. > >~Andrew -- Sent from my mobile phone. Please excuse brevity and lack of formatting.