Re: [PATCHv3] virtio-spec: 64 bit features, used/avail event, fixes

   Hi,

E.g. with 32 bridges, and 32 devices behind each one,
the available 64K space gets us only 64 bytes per device.

15 bridges (with io window enabled) max, the smallest io window you can 
assign to a bridge is 4k, and you need some space for the devices on the 
root bus ...

cheers,
   Gerd