Nouveau - Sep 2025 - [RFC v2 03/14] vfio/nvidia-vgpu: introduce vGPU type uploading

On Thu, Sep 04, 2025 at 11:41:03AM +0200, Danilo Krummrich wrote:
> > Another note: I don't see any use of the auxiliary bus in vGPU,
any clients
> > should attach via the auxiliary bus API, it provides proper matching
where
> > there's more than on compatible GPU in the system. nova-core
already registers
> > an auxiliary device for each bound PCI device.
The driver here attaches to the SRIOV VF pci_device, it should obtain the
nova-core handle of the PF device through pci_iov_get_pf_drvdata().

This is the expected design of VFIO drivers because the driver core
does not support a single driver binding to two devices (aux and VF)
today.

Jason

On Thu Sep 4, 2025 at 2:15 PM CEST, Jason Gunthorpe
wrote:
> On Thu, Sep 04, 2025 at 11:41:03AM +0200, Danilo Krummrich wrote:
>
>> > Another note: I don't see any use of the auxiliary bus in
vGPU, any clients
>> > should attach via the auxiliary bus API, it provides proper
matching where
>> > there's more than on compatible GPU in the system. nova-core
already registers
>> > an auxiliary device for each bound PCI device.
>
> The driver here attaches to the SRIOV VF pci_device, it should obtain the
> nova-core handle of the PF device through pci_iov_get_pf_drvdata().
>
> This is the expected design of VFIO drivers because the driver core
> does not support a single driver binding to two devices (aux and VF)
> today.
Yeah, that's for the VF PCI devices, but I thought vGPU will also have some
kind
of "control instance" for each physical device through which it can
control the
creation of VFs?