Re: [PATCH 5/6] vdpa: introduce virtio pci driver

From: Jason Wang
Date: Tue Jun 09 2020 - 01:55:46 EST



On 2020/6/8 äå9:29, Michael S. Tsirkin wrote:
On Mon, Jun 08, 2020 at 06:07:36PM +0800, Jason Wang wrote:
On 2020/6/8 äå5:54, Michael S. Tsirkin wrote:
On Mon, Jun 08, 2020 at 05:46:52PM +0800, Jason Wang wrote:
On 2020/6/8 äå5:45, Michael S. Tsirkin wrote:
On Mon, Jun 08, 2020 at 05:43:58PM +0800, Jason Wang wrote:
Looking at
pci_match_one_device() it checks both subvendor and subdevice there.

Thanks
But IIUC there is no guarantee that driver with a specific subvendor
matches in presence of a generic one.
So either IFC or virtio pci can win, whichever binds first.
I'm not sure I get there. But I try manually bind IFCVF to qemu's
virtio-net-pci, and it fails.

Thanks
Right but the reverse can happen: virtio-net can bind to IFCVF first.
That's kind of expected. The PF is expected to be bound to virtio-pci to
create VF via sysfs.

Thanks



Once VFs are created, don't we want IFCVF to bind rather than
virtio-pci?

Yes, but for PF we need virtio-pci.

Thanks

(Ab)using the driver_data field for this is an option.
What do you think?


Maybe you can elaborate more on this idea?

Thanks