On Fri, Jun 30, 2023 at 02:52:52PM +0530, Ani Sinha wrote: > > > > On 30-Jun-2023, at 2:13 PM, Michael S. Tsirkin <m...@redhat.com> wrote: > > > > 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. > > Hmm, I tried this: > > -device pcie-root-port,id=p \ > -device igb,bus=p,addr=0x2.0x0 \ > -device igb,bus=p,addr=0x0.0x0 \ > > The guest only found the second igb device not the first. You can try too.
Because next parameter in pcie_ari_init does not match. > > > >>> 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 ... > > Indeed. Everyone uses bluetooth these days. I for one is happy that the jack > is gone (and they were bold enough to do it while Samsung and others still > carry the useless port ) :-) > > > > >>> and the benefit > >>> is not guaranteed. > >>> > >>> -- > >>> MST
