John Hubbard
2025-Oct-01 23:51 UTC
[PATCH 0/2] rust: pci: expose is_virtfn() and reject VFs in nova-core
On 10/1/25 4:47 PM, Joel Fernandes wrote:>> On Oct 1, 2025, at 7:00?PM, John Hubbard <jhubbard at nvidia.com> wrote: >> ?On 10/1/25 3:52 PM, Danilo Krummrich wrote: >>>> On Thu Oct 2, 2025 at 12:38 AM CEST, John Hubbard wrote: >>>> On 10/1/25 6:52 AM, Zhi Wang wrote: >>>>> On 1.10.2025 13.32, Danilo Krummrich wrote: >>>>>> On Wed Oct 1, 2025 at 3:22 AM CEST, John Hubbard wrote: >>>>>>> On 9/30/25 5:29 PM, Alistair Popple wrote: >>>>>>>> On 2025-10-01 at 08:07 +1000, John Hubbard <jhubbard at nvidia.com> wrote... >>>> ... > Here is my opinion and correct me if I missed something: > > It feels premature to remove the option of nova-core binding to a VF, since other options to disable auto probing do exist as Jason pointed out. > > Taking a parallel with VFIO pass through for instance, the user already has to do some diligence like preventing drivers from binding and then making vfio-pci bind to the device IDs. This case is similar though slightly different, but VFIO setup requires some configuration anyway so will it really improve anything? > > I quietly suggest holding on till there is a real need or we are sure nova cannot bind to, or operate on a VF. ThisI'm confident that nova-core cannot properly handle a VF with *today's* code. There is no expectation at all for a VF to show up--yet. Which is why I think it's appropriate to skip it right now. thanks, -- John Hubbard
Danilo Krummrich
2025-Oct-01 23:55 UTC
[PATCH 0/2] rust: pci: expose is_virtfn() and reject VFs in nova-core
On Thu Oct 2, 2025 at 1:51 AM CEST, John Hubbard wrote:> On 10/1/25 4:47 PM, Joel Fernandes wrote: >>> On Oct 1, 2025, at 7:00?PM, John Hubbard <jhubbard at nvidia.com> wrote: >>> ?On 10/1/25 3:52 PM, Danilo Krummrich wrote: >>>>> On Thu Oct 2, 2025 at 12:38 AM CEST, John Hubbard wrote: >>>>> On 10/1/25 6:52 AM, Zhi Wang wrote: >>>>>> On 1.10.2025 13.32, Danilo Krummrich wrote: >>>>>>> On Wed Oct 1, 2025 at 3:22 AM CEST, John Hubbard wrote: >>>>>>>> On 9/30/25 5:29 PM, Alistair Popple wrote: >>>>>>>>> On 2025-10-01 at 08:07 +1000, John Hubbard <jhubbard at nvidia.com> wrote... >>>>> ... >> Here is my opinion and correct me if I missed something: >> >> It feels premature to remove the option of nova-core binding to a VF, since other options to disable auto probing do exist as Jason pointed out. >> >> Taking a parallel with VFIO pass through for instance, the user already has to do some diligence like preventing drivers from binding and then making vfio-pci bind to the device IDs. This case is similar though slightly different, but VFIO setup requires some configuration anyway so will it really improve anything? >> >> I quietly suggest holding on till there is a real need or we are sure nova cannot bind to, or operate on a VF. This > > I'm confident that nova-core cannot properly handle a VF with *today's* code. > There is no expectation at all for a VF to show up--yet. > > Which is why I think it's appropriate to skip it right now.I agree with John. If a driver does not support a certain device, it is not the user's responsibility to prevent probing. Currently nova-core does not support VFs, so it should never get probed for them in the first place.