Subject: Re: [RFC v2, net-next, PATCH 4/4] net/cpsw_switchdev: add switchdev mode of operation on cpsw driver

From: Ilias Apalodimas <[email-masked]>
Date: Wed, 20 Jun 2018 21:03:42 +0300

Hi Florian,

On Wed, Jun 20, 2018 at 10:58:26AM -0700, Florian Fainelli wrote:
> On 06/20/2018 10:51 AM, Ilias Apalodimas wrote:
> > Hello Ivan,
> > On Wed, Jun 20, 2018 at 02:56:48PM +0200, Ivan Vecera wrote:
> >> On 18.6.2018 22:19, Ilias Apalodimas wrote:
> >>> Jiri proposed using devlink, which makes sense, but i am not sure it's
> >>> applicable on this patchset. This will change the driver completely and will
> >>> totally break backwards compatibility.
> >>
> >> Another good reason for a new driver.
> >>
> >> I.
> > This is actually conflicting at least to my understanding. Jiri proposed using 
> > devlink was used as an alternative method to enable a new mode instead of 
> > adding it on a .config option. A new driver wouldn't have a need for that right?
> 
> Correct, with a new driver would likely behave correctly upon being
> probed such that you could have your switch ports act as normal network
> devices from which you could run IP-config and do NFS boot.
The current driver also does NFS properly and the 2 ethernet ports act as normal
network interfaces. The NFS section in the cover letter
is to cover the cases were users running on NFS need to change the running
switch configuration(starting from adding the 2 interfaces on a bridge). 
Since iproute2 is located on the NFS filesystem the moment
network connectivity is lost, you loose the ability to perform further
configuration and in certian configuration scenarios render the device
unusable.
> -- 
> Florian

Thanks
Ilias