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

[Paolo Bonzini]

On 12/14/2010 04:41 PM, Alex Williamson wrote:
> >  Maybe in this particular case the advantage is minimal.
> >  But it seems easier to stick to a rule of no more version
> >  bumps than argue about each case.
>
> Do we have such a rule?  If we have a subsection who's needed function
> is return 1, I think that's a good indication that it's not appropriate
> for a subsection and the end result is equivalent to bumping the main
> driver vmstate version.  It's convoluted to try to hide a one-way
> upgrade in a subsection.  Thanks,

Indeed, subsections are for data that is rarely needed so that there's 
some chance (sometimes ~100%) of migration working seemlessly.  In this 
case it's either no-bump-and-live-with-the-consequences, or changing the 
version id.

Paolo