[Qemu-devel] Re: [PATCH] rtl8139: IO memory is not part of vmstate

[Michael S. Tsirkin]

On Mon, Dec 13, 2010 at 11:00:44AM -0700, Alex Williamson wrote:
> On Mon, 2010-12-13 at 19:50 +0200, Michael S. Tsirkin wrote:
> > On Mon, Dec 13, 2010 at 10:43:22AM -0700, Alex Williamson wrote:
> > > So, unfortunately, I stand by my original patch.
> > 
> > What about the one that put -1 in saved index for a hotplugged device?
> 
> There are still examples that don't work even without hotplug (example 2
> and example 3 after the reboot).  That hack limits the damage, but still
> leaves a latent bug for reboot and doesn't address the non-hotplug
> scenarios.  So, I don't think it's worthwhile to pursue, and we
> shouldn't pretend we can use it to avoid bumping the version_id.
> Thanks,
> 
> Alex

I guess when we bump it we tell users: migration is completely
borken to the old version, don't even try it.

Is there a way for libvirt to discover such incompatibilities
and avoid the migration?

-- 
MST