Re: [PATCH net-next v2 4/7] devlink: allow subports on devlink PCI ports

[Jakub Kicinski <jakub.kicinski@netronome.com>]

On Thu, 14 Mar 2019 22:35:36 +0000, Parav Pandit wrote:
> > > Then instances of flavour pci_vf are going to appear in the same
> > > devlink instance. Those are the switch ports:
> > > pci/0000:05:00.0/10002: type eth netdev enp5s0npf0pf0s0
> > >                         flavour pci_vf pf 0 vf 0
> > >                         switch_id 00154d130d2f peer pci/0000:05:10.1/0
> > > pci/0000:05:00.0/10003: type eth netdev enp5s0npf0pf0s0
> > >                         flavour pci_vf pf 0 vf 0 subport 1
> > >                         switch_id 00154d130d2f peer pci/0000:05:10.1/1
> > >
> > > With that, peers are going to appear too, and those are the actual
> > > VF/VF
> > > subport:
> > > pci/0000:05:10.1/0: type eth netdev ??? flavour pci_vf_host
> > >                     peer pci/0000:05:00.0/10002
> > > pci/0000:05:10.1/1: type eth netdev ??? flavour pci_vf_host
> > >                     peer pci/0000:05:00.0/10003
> > >
> > > Later you can push this VF along with all subports to VM. So in VM,
> > > you are going to see the VF like this:
> > > $ devlink dev
> > > pci/0000:00:08.0
> > > $ devlink port
> > > pci/0000:00:08.0/0: type eth netdev ??? flavour pci_vf_host
> > > pci/0000:00:08.0/1: type eth netdev ??? flavour pci_vf_host
> > >
> > > And back to your question of how are they connected in eswitch.
> > > That is totally up to the original user John who did the creation.
> > > He is in charge of the eswitch on baremetal, he would configure the
> > > forwarding however he likes.  
> > 
> > Ack, so I think you're saying VM has to communicate to the cloud
> > environment to have this provisioned using some service API, not a kernel
> > API.  That's what I wanted to confirm.
> > 
> > I don't see any benefit to having the "host ports" under devlink, as such I
> > think it's a matter of preference.   
>
> We need 'host ports' to configure parameters of this 
> host port which is not exposed by the rep-netdev.
> Such as mac address.

Please look at the quote of what Jiri wrote above - the host port gets
passed to the VM, you can't use it as a handle to set the MAC.

The way to set the MAC remains:

# devlink port set pci/0000:05:00.0/10002 peer mac_addr 00:11:22:33:44:55

(using the port ids from above)