On Tue, Oct 10, 2023 at 12:59:37PM -0300, Jason Gunthorpe wrote: > On Tue, Oct 10, 2023 at 11:14:56AM -0400, Michael S. Tsirkin wrote: > > > I suggest 3 but call it on the VF. commands will switch to PF > > internally as needed. For example, intel might be interested in exposing > > admin commands through a memory BAR of VF itself. > > FWIW, we have been pushing back on such things in VFIO, so it will > have to be very carefully security justified. > > Probably since that is not standard it should just live in under some > intel-only vfio driver behavior, not in virtio land. > > It is also costly to switch between pf/vf, it should not be done > pointlessly on the fast path. > > Jason Currently, the switch seems to be just a cast of private data. I am suggesting keeping that cast inside virtio. Why is that expensive?