Re: crash with Xen dom0 image from kdump
by Kazuo Moriwaka
Hello Dave,
# I append crash-utility list to Cc
From: Dave Anderson <anderson(a)redhat.com>
Subject: Re: crash with Xen dom0 image from kdump
Date: Thu, 01 Jun 2006 08:39:01 -0400
> Kazuo Moriwaka wrote:
>
> > Hello,
> >
> > From: Dave Anderson <anderson(a)redhat.com>
> > Subject: Re: crash with Xen dom0 image from kdump
> > Date: Wed, 31 May 2006 16:20:15 -0400
> >
> > >
> > > Hey guys,
> > >
> > > I've got the vmcore file from which Kazuo generated the
> > > "simulated" xendump dumpfile. I have a question regarding
> > > the makeup of the the vmcore file -- are the physical addresses
> > > referred to by each PT_LOAD segment based upon:
> > >
> > > 1. machine addresses, or
> > > 2. pseudo-physical addresses as perceived by the dom0 vmlinux kernel?
> > >
> > > Dave
> >
> > It's 1.
> > vmcore is made by kexec-ed linux kernel (not on xen, but on machine) kdump.
> > The kernel doesn't know about xen or domains except register info.
> > Register info is for dom0.
> >
>
> Ok, good...
>
> Next question -- how did you find dom0's phys_to_machine_mapping[]
> array from the vmcore in order to create the xendump?
I use xen executable binary with symbols to find 'dom0' global symbol
in xen.
In x86_32 arch, dom0->vcpu[0].arch->guest_table has pagetable address
for domain0 guest kernel.
After it, I found 'phys_to_machine_mapping'.
For other domains, 'domain_list' is point list of struct domain.
I'll attach my latest dom0cut script. 'dom0cut_x86_32.py' contains
names of symbols and structs to get dom0 image.
> > p.s.
> > Do you have any plan to support xen hypervisor itself with crash?
> > If there's, I want to help it.
> >
>
> I don't -- at least at this time. (My next primary task is to get crash
> working with x86 PAE kernels.)
>
> But it would be an interesting project
> to undertake. I'm not sure whether or how it would cleanly fit into
> the crash source code, or whether it should be an executable of
> its own. But by all means, if you want to undertake the task, be
> my guest!
I'm also not sure about them, yet. In anyway, at first, I'll help you to
support xen's vmcore format.
It is also a part of a way to support xen hypervisor.
regards,
--
Kazuo Moriwaka <moriwaka(a)valinux.co.jp>
18 years
- 4
- 7