Re: [Qemu-devel] [PATCH] Migration compatibility for serial

[Michael S. Tsirkin]

On Wed, Jun 17, 2015 at 10:11:48AM +0200, Paolo Bonzini wrote:
> 
> 
> On 17/06/2015 09:52, Michael S. Tsirkin wrote:
> > > No, please.  Upstream QEMU doesn't want to get into judgement about when
> > > migration quality might be "good enough" that you can drop subsections.
> > >  It's one thing to perfect the .needed functions to make the appearance
> > > of subsections as unlikely as possible, but adding flags is not
> > > something we've done so far---and not something at least *I* want to do.
> > 
> > Not like this, sure.  But e.g. patches that force specific fields to
> > behave in a way consistent with QEMU 2.2, with appropriate
> > doducmentation would be ok I think.
> 
> That's not what 2.2 means in "pc-i440fx-2.2".  It means "same hardware
> as 2.2", not "bug-compatible with 2.2".
> 
> Refining the .needed functions (e.g. see commit bfa7362889) is just
> that: describing when a subsection is needed.  Forcing specific fields
> to behave in a way consistent with QEMU 2.2 is bug compatibility.
> 
> Paolo

We do bug-compatible if it's not a big pain, too.

-- 
MST