On (Tue) 15 Feb 2011 [17:13:13], Anthony Liguori wrote:
> On 02/15/2011 10:26 AM, Chris Wright wrote:
> >
> >revisit new -> old migration
> >- Amit offers virtio-serial patches and some legwork
>
> So, to me, migration correctness trumps compatibility. I don't
> think compatibility is useful if it means that a guest may fail
> during migration. We have subsections as a way to support the cases
> where it's safe to migrate to an old version only if a feature is
> not being used or a corner case is not currently happening. This is
> the best way to approach the problem.
>
> If a subsection won't work, that means you want to migrate when
> you're completely sure that migrating will break a guest. That
> doesn't seem reasonable at all to me.
>
> I think in the last discussion on Amit's patches, I had suggested
> that subsections could be used to allow migration when there wasn't
> any queued data. I think this is the best we can do while
> preserving correctness.
The only problem is that virtio hasn't been converted over to vmstate,
which is necessary for subsections.
Amit
