RE: [RFC net-next 0/8] Introducing subdev bus and devlink extension

[Parav Pandit]

> From: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
> Sent: Wednesday, June 9, 2021 2:46 PM
> 
[..]

> >> Is there any reason why VF use its own devlink instance?
> >
> > Primary use case for VFs is virtual environments where guest isn't
> > trusted, so tying the VF to the main devlink instance, over which
> > guest should have no control is counter productive.
> 
> The security is mainly about VF using in container case, right?
> Because VF using in VM, it is different host, it means a different devlink
> instance for VF, so there is no security issue for VF using in VM case?
> But it might not be the case for VF using in container?
Devlink instance has net namespace attached to it controlled using devlink reload command.
So a VF devlink instance can be assigned to a container/process running in a specific net namespace.

$ ip netns add n1
$ devlink dev reload pci/0000:06:00.4 netns n1
                                     ^^^^^^^^^^^^^
                                     PCI VF/PF/SF.

> Also, there is a "switch_id" concept from jiri's example, which seems to be
> not implemented yet?

switch_id is present for switch ports in [1] and documented in [2].

[1] /sys/class/net/representor_netdev/phys_switch_id.
[2] https://www.kernel.org/doc/Documentation/networking/switchdev.txt " Switch ID"