Messages in this thread | | | From | "Rustad, Mark D" <> | Subject | Re: [virtio-dev] [pci PATCH v7 2/5] virtio_pci: Add support for unmanaged SR-IOV on virtio_pci devices | Date | Tue, 3 Apr 2018 19:18:23 +0000 |
| |
On Apr 3, 2018, at 11:27 AM, Michael S. Tsirkin <mst@redhat.com> wrote:
>> I'm not sure why you would need a feature bit. The capability is >> controlled via PCI configuration space. If it is present the device >> has the capability. If it is not then it does not. >> >> Basically if the PCI configuration space is not present then the sysfs >> entries will not be spawned and nothing will attempt to use this >> function. >> >> - ALex > > It's about compability with older guests which ignore the > capability. > > The feature is thus helpful so host knows whether guest supports VFs.
This is not about a guest creating its own VFs. This is about a host PF that happens to have a virtio interface to be able to create virtio VFs that can be assigned to guests. Nothing changes at all from a guest perspective. Or maybe I am not understanding what you mean by "whether guest supports VFs".
-- Mark Rustad, Networking Division, Intel Corporation [unhandled content-type:application/pgp-signature] | |