Subject: Re: [PATCH/RFC net-next 1/2] devlink: expose port function commands to assign VFs to multiple netdevs

From: Leon Romanovsky <[email-masked]>
Date: Wed, 8 Feb 2023 13:21:22 +0200

On Mon, Feb 06, 2023 at 06:42:27PM -0800, Jakub Kicinski wrote:
> On Mon,  6 Feb 2023 16:36:02 +0100 Simon Horman wrote:
> > +VF assignment setup
> > +---------------------------
> > +In some cases, NICs could have multiple physical ports per PF. Users can assign VFs to
> > +different ports.
> 
> Please make sure you run make htmldocs when changing docs,
> this will warn.
> 
> > +- Get count of VFs assigned to physical port::
> > +
> > +    $ devlink port show pci/0000:82:00.0/0
> > +    pci/0000:82:00.0/0: type eth netdev enp130s0np0 flavour physical port 0 splittable true lanes 4
> 
> Physical port has VFs? My knee jerk reaction is that allocating
> resources via devlink is fine but this seems to lean a bit into
> forwarding. How do other vendors do it? What's the mapping of VFs
> to ports?

I don't understand the meaning of VFs here. If we are talking about PCI
VFs, other vendors follow PCI spec "9.3.3.3.1 VF Enable" section, which
talks about having one bit to enable all VFs at once. All these VFs will
have separate netdevs.

> 
> What do you suggest should happen when user enables switchdev mode?
>