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 <kernel-path>". >> 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 at 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
