On Wed, Jul 11, 2018 at 11:53:44AM +0200, Cornelia Huck wrote: > On Tue, 10 Jul 2018 17:07:37 -0700 > Siwei Liu <losewe...@gmail.com> wrote: > > > On Mon, Jul 9, 2018 at 6:54 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > > > On Mon, Jul 09, 2018 at 06:11:53PM -0700, si-wei liu wrote: > > >> The plan is to enable group ID based matching in the first place rather > > >> than > > >> match by MAC, the latter of which is fragile and problematic. > > > > > > It isn't all that fragile - hyperv used same for a while, so if someone > > > posts working patches with QEMU support but before this grouping stuff, > > > I'll happily apply them. > > > > I wouldn't box the solution to very limited scenario just because of > > matching by MAC, the benefit of having generic group ID in the first > > place is that we save the effort of maintaining legacy MAC based > > pairing that just adds complexity anyway. Currently the VF's MAC > > address cannot be changed by either PF or by the guest user is a > > severe limitation due to this. The other use case is that PT device > > than VF would generally have different MAC than the standby virtio. We > > shouldn't limit itself to VF specific scenario from the very > > beginning. > > So, this brings me to a different concern: the semantics of > VIRTIO_NET_F_STANDBY. > > * The currently sole user seems to be the virtio-net Linux driver. > * The commit messages, code comments and Documentation/ all talk about > matching by MAC. > * I could not find any proposed update to the virtio spec. (If there > had been an older proposal with a different feature name, it is not > discoverable.) > > VIRTIO_NET_F_STANDBY is a host <-> guest interface. As there's no > official spec, you can only go by the Linux implementation, and by that > its semantics seem to be 'match by MAC', not 'match by other criteria'. > > How is this supposed to work in the long run?
We definitely need a spec patch for VIRTIO_NET_F_STANDBY documenting existing semantics. Sridhar, do you plan to take a look? -- MST --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscr...@lists.oasis-open.org For additional commands, e-mail: virtio-dev-h...@lists.oasis-open.org
