From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp02.citrix.com ([66.165.176.63]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1X5Zlp-0007Cr-AH for kexec@lists.infradead.org; Fri, 11 Jul 2014 12:17:46 +0000 Message-ID: <53BFD5D1.2080207@citrix.com> Date: Fri, 11 Jul 2014 13:17:21 +0100 From: David Vrabel MIME-Version: 1.0 Subject: Re: Can't load bzImage crashkernel on xen system with 32 bit kernel References: <53BBC94B.8060905@overnetdata.com> <20140710074713.GA23099@dhcp-17-89.nay.redhat.com> <53BE66C5.6090604@overnetdata.com> <20140711075835.GA21010@dhcp-17-89.nay.redhat.com> <53BFB093.10307@citrix.com> <53BFCA2C.6010403@overnetdata.com> In-Reply-To: <53BFCA2C.6010403@overnetdata.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Anthony Wright , WANG Chao Cc: Daniel Kiper , Simon Horman , kexec@lists.infradead.org On 11/07/14 12:27, Anthony Wright wrote: > On 11/07/2014 10:38, David Vrabel wrote: >> On 11/07/14 08:58, WANG Chao wrote: >>> On 07/10/14 at 11:11am, Anthony Wright wrote: >>>> Hi Chao, >>>> >>>> Thanks for looking at this. >>>> >>>> On 10/07/2014 08:47, WANG Chao wrote: >>>>> Hi, Anthony >>>>> >>>>> On 07/08/14 at 11:34am, Anthony Wright wrote: >>>>>> After successfully modifying kexec-tools to get it to load a crashkernel >>>>>> on a standard 32 bit linux 3.10.17 kernel, I tried to get it to load the >>>>>> same crashkernel on the same 32 bit linux kernel running under xen >>>>>> 4.4.0, but get the error "Cannot load ". >> Are you trying to do an in-guest kexec or are you trying to kexec from Xen? >> >> If it's the latter, it should just work with 32 and 64-bit images, Xen >> 4.4 and kexec-tools 2.0.5 or later. >> >> In-guest kexec doesn't work at all. >> >> David > I'm trying to do the kexec from within a 32 bit linux 3.10.17 Dom0 > running under a 64 bit xen 4.4.0. When you say 'guest', does that mean > DomU's or does that include Dom0 as well? If it includes Dom0 could you > point me at some documentation to explain how/if it's possible to set up > kexec/kdump for Dom0. > > I have a Dom0 kernel that's crashing infrequently. I can't reproduce it > easily and all the standard diagnostic techniques haven't been very > helpful. I'd hoped to generate a crashdump using kexec/kdump to help > diagnose the problem. I would suggest trying a Xen kexec and exec'ing your crashdump kernel (which will then be running on baremetal). You will need to reserve a region of memory for the crash kernel on the Xen command line (e.g., crashkernel=64M@32M) and use kexec-tools 2.0.5 or later. We don't actually collect memory dumps from this environment (only basic PCPU/VCPU state, Xen/dom0 backtraces, and console logs) so I'm not sure what the status of tools for this are. Daniel Kiper might know. David _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec