[Qemu-devel] Re: [patch 3/3] UHCI: Substate section for migration of remote wakeup feature

[Marcelo Tosatti]

On Wed, Dec 01, 2010 at 08:14:22PM +0100, Juan Quintela wrote:
> Gerd Hoffmann <address@hidden> wrote:
> > On 12/01/10 17:47, Marcelo Tosatti wrote:
> >> Use a subsection to migrate remote wakeup feature only when used by the 
> >> guest.
> >
> > Yea, right, this must be saved.  But certainly not by the UHCI
> > adapter, it belongs into the usb devices.  Some of them don't save
> > state at all today, which makes it a bit tricky to do this in a way
> > that migration to older versions keeps working at least as long as
> > remote wakeup isn't used ...
> >
> > Juan, any idea?
> 
> Second thought.
> 
> Only to add sections for all devices that don't have one.  But the
> problem is that we have optional subsections, not optional subsections
> (it is not a way to not send a section because no value there).
> 
> Later, Juan.

Which breaks migration for older versions. Which lowers the
applicability of s/r.

Yes, remote_wakeup does not belong to UHCI, but i dont see another
solution. Or break migration upstream and use the hack for vendors.