Re: [Qemu-devel] [Question] dump memory when host pci device is used by guest

[Richard W.M. Jones]

On Fri, Oct 07, 2011 at 12:16:07PM +0200, Jan Kiszka wrote:
> On 2011-10-07 11:46, Wen Congyang wrote:
> > Currently, virsh dump uses monitor command migrate to dump guest's memory
> > to file, and we can use crash to analyze the file.
> > 
> > Unfortunately, virsh dump can not work if guest uses host pci device. The
> > reason is that the device's status is also needed to migrate to remote 
> > machine,
> > and the host pci device's status is not stored in qemu. So it is 
> > unmigratable.
> > 
> > I think we can  we can add a option to qmp command migrate(eg: skip) to 
> > allow
> > the user to skip the check, and this option should be used only when dumping
> > the guest's memory.
> 
> Why not simply attach gdb? That works independently of migration.

It's a lot more hairy and requires dev tools to be installed on the
production host.

The core file is technically simple, has no dependencies, can be moved
to another machine for analysis, and contains all the data (not just a
backtrace).

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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