Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756008Ab2KWLOK (ORCPT ); Fri, 23 Nov 2012 06:14:10 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:42717 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755407Ab2KWLOJ (ORCPT ); Fri, 23 Nov 2012 06:14:09 -0500 Date: Fri, 23 Nov 2012 12:13:08 +0100 From: Daniel Kiper To: Ian Campbell Cc: Jan Beulich , "xen-devel@lists.xensource.com" , "konrad.wilk@oracle.com" , Andrew Cooper , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , "mingo@redhat.com" , "Eric W. Biederman" , "H. Peter Anvin" , "tglx@linutronix.de" Subject: Re: [Xen-devel] [PATCH v2 01/11] kexec: introduce kexec_ops struct Message-ID: <20121123111308.GB3002@host-192-168-1-59.local.net-space.pl> References: <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> <18e831d4-910d-4f58-8911-1398b96e3a47@email.android.com> <50AED7B8.7040902@citrix.com> <50AF55B102000078000AABF3@nat28.tlf.novell.com> <20121123103726.GB2921@host-192-168-1-59.local.net-space.pl> <1353667868.13542.218.camel@zakaz.uk.xensource.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1353667868.13542.218.camel@zakaz.uk.xensource.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1189 Lines: 27 On Fri, Nov 23, 2012 at 10:51:08AM +0000, Ian Campbell wrote: > On Fri, 2012-11-23 at 10:37 +0000, Daniel Kiper wrote: > > On Fri, Nov 23, 2012 at 09:53:37AM +0000, Jan Beulich wrote: > > > >>> On 23.11.12 at 02:56, Andrew Cooper wrote: > > > > The crash region (as specified by crashkernel= on the Xen command line) > > > > is isolated from dom0. > > > >[...] > > > > > > But all of this _could_ be done completely independent of the > > > Dom0 kernel's kexec infrastructure (i.e. fully from user space, > > > invoking the necessary hypercalls through the privcmd driver). > > > > No, this is impossible. kexec/kdump image lives in dom0 kernel memory > > until execution. > > Are you sure? I could have sworn they lived in the hypervisor owned > memory set aside by the crashkernel= parameter as Andy suggested. I am sure. It is moved to final resting place when relocate_kernel() is called by hypervisor. Daniel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/