Re: [Qemu-devel] [Xen-devel] [PATCH 2/2] xenfb: Add comment documentation

[Ian Campbell]

On Fri, 2014-09-26 at 11:20 +0100, Owen Smith wrote:
> > > + * page-gref
> > > + *   Values: <uint32_t>
> > > + *   Only required if "page-ref" is NOT set.
> > > + *
> > > + *   A grant reference to the memory page to be mapped for the shared
> > ring
> > > + *   structures. Must be present if "page-ref" is not present.
> > 
> > Should there be some negotiation for which of page-ref or page-gref is
> > required/preferred by the backend?
> > 
> > The same applies to kbdif as well.
> > 
> 
> I've not added negotiation, as I wanted minimum changes when "page-ref" is 
> specified.
> With the kbdif device only, not investigated the vfb, a backend only 
> supporting "page-gref" 
> will break a lot of frontends (I saw breaks in Ubuntu, which advertises both 
> if I forced page-gref)

Is this patch/series documenting existing behaviour or the new behaviour
which you are currently implementing? Both patches have the same title
and essentially the same commit message (list of fields), so I can't
tell.