Michael S. Tsirkin
2023-Oct-11 06:43 UTC
[PATCH vfio 10/11] vfio/virtio: Expose admin commands over virtio device
On Tue, Oct 10, 2023 at 11:13:30PM -0700, Christoph Hellwig wrote:> 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. > > Btw, what is that intel thing everyone is talking about? And why > would the virtio core support vendor specific behavior like that?It's not a thing it's Zhu Lingshan :) intel is just one of the vendors that implemented vdpa support and so Zhu Lingshan from intel is working on vdpa and has also proposed virtio spec extensions for migration. intel's driver is called ifcvf. vdpa composes all this stuff that is added to vfio in userspace, so it's a different approach. -- MST
Christoph Hellwig
2023-Oct-11 06:59 UTC
[PATCH vfio 10/11] vfio/virtio: Expose admin commands over virtio device
On Wed, Oct 11, 2023 at 02:43:37AM -0400, Michael S. Tsirkin wrote:> > Btw, what is that intel thing everyone is talking about? And why > > would the virtio core support vendor specific behavior like that? > > It's not a thing it's Zhu Lingshan :) intel is just one of the vendors > that implemented vdpa support and so Zhu Lingshan from intel is working > on vdpa and has also proposed virtio spec extensions for migration. > intel's driver is called ifcvf. vdpa composes all this stuff that is > added to vfio in userspace, so it's a different approach.Well, so let's call it virtio live migration instead of intel. And please work all together in the virtio committee that you have one way of communication between controlling and controlled functions. If one extension does it one way and the other a different way that's just creating a giant mess.