> From: Jason Gunthorpe <jgg@xxxxxxxxxx> > Sent: Wednesday, September 22, 2021 8:57 PM > > On Wed, Sep 22, 2021 at 03:53:52AM +0000, Tian, Kevin wrote: > > > Actually this was one open we closed in previous design proposal, but > > looks you have a different thought now. > > > > vfio maintains one ioas per container. Devices in the container > > can be attached to different domains (e.g. due to snoop format). Every > > time when the ioas is updated, every attached domain is updated > > in accordance. > > > > You recommended one-ioas-one-domain model instead, i.e. any device > > with a format incompatible with the one currently used in ioas has to > > be attached to a new ioas, even if the two ioas's have the same mapping. > > This leads to compatibility check at attaching time. > > > > Now you want returning back to the vfio model? > > Oh, I thought we circled back again.. If we are all OK with one ioas > one domain then great. yes, at least I haven't seen a blocking issue with this assumption. Later when converting vfio type1 into a shim, it could create multiple ioas's if container would have a list of domains before the shim. > > > > If think sis taking in the iommfd_device then there isn't a logical > > > place to signal the PCIness > > > > can you elaborate? > > I mean just drop it and document it. > got you
