Re: [Qemu-devel] Re: Live migration protocol, device features, ABIs and other beasts

[Paolo Bonzini]

On 11/23/2009 02:51 PM, Eduardo Habkost wrote:
> Right, but I wouldn't be surprised if a user complains that "I know that
> my guest don't use that VM feature, so I want to be able to migrate to
> an older version anyway".

That's a bit more tricky.  What if the older version doesn't support 
sound (just making up an example) and you know that you're not using a 
client that plays sound, but still the sound card is part of the 
machine?  I think there is no doubt that the migration (or save/restore) 
should be aborted in that case.

I would not generalize very much, the problem that Dor posed is very 
specific and probably quite rare.  However, it's real.

Paolo