On Wed, Jan 11, 2012 at 09:28:27AM -0600, Anthony Liguori wrote: > On 01/11/2012 09:21 AM, Michael S. Tsirkin wrote: > >On Wed, Jan 11, 2012 at 09:15:49AM -0600, Anthony Liguori wrote: > >>>This is similar to what we have now. But it's still buggy: e.g. if guest > >>>updates MAC byte by byte, we have no way to know when it's done doing > >>>so. > >> > >>This is no different than a normal network card. You have to use a > >>secondary register to trigger an update. > >> > >>Regards, > >> > >>Anthony Liguori > > > >Possible but doesn't let us layer nicely to allow unchanged drivers > >that work with all transports (new pci, old pci, non pci). > > If we declare config space LE, then we have to touch all drivers. > There's no way around it because the virtio API is byte-based, not > word based.
Fine but don't we want to be compatible with old hypervisors? > This is why I'm suggesting making the virtio API (and then the > virtio-pci ABI) word based. It gives us the flexibility to make > endianness a property of the transport and not a property of the > devices. > > Regards, > > Anthony Liguori Some fields are 64 bit, this is still tricky to do atomically. What's the objection to using a config VQ? _______________________________________________ Virtualization mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/virtualization
