On Fri, Jun 30, 2023 at 02:06:59PM +0530, Ani Sinha wrote: > > > > On 30-Jun-2023, at 2:02 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > > > > On Fri, Jun 30, 2023 at 01:11:33PM +0530, Ani Sinha wrote: > >>> > >>> Thus the check for unoccupied function 0 needs to use pci_is_vf() instead > >>> of checking ARI capability, and that can happen in > >>> do_pci_register_device(). > >>> > >>>> Also where do you propose we move the check? > >>> > >>> In pci_qdev_realize(), somewhere after pc->realize() and before option > >>> ROM loading. > >> > >> Hmm, I tried this. The issue here is something like this would be now > >> allowed since the PF has ARI capability: > >> > >> -device pcie-root-port,id=p -device igb,bus=p,addr=0x2.0x0 > >> > >> The above should not be allowed and when used, we do not see the igb > >> ethernet device from the guest OS. > > > > I think it's allowed because it expects you to hotplug function 0 later, > > This is about the igb device being plugged into the non-zero slot of the > pci-root-port. The guest OS ignores it.
yes but if you later add a device with ARI and with next field pointing slot 2 guest will suddently find both. > > no? > > > > I am quite worried about all this work going into blocking > > what we think is disallowed configurations. We should have > > maybe blocked them originally, but now that we didn't > > there's a non zero chance of regressions, > > Sigh, There's value in patches 1-4 I think - the last patch helped you find these. so there's value in this work. > no medals here for being brave :-) Try removing support for a 3.5mm jack next. Oh wait ... > > and the benefit > > is not guaranteed. > > > > -- > > MST > >
