Re: [RFC net-next 0/5] Support for PHY test modes

[David Miller]

From: Florian Fainelli <f.fainelli@xxxxxxxxx>
Date: Tue, 1 May 2018 10:21:54 -0700

> On 04/30/2018 04:24 PM, Andrew Lunn wrote:
>>> Turning these tests on will typically result in the link partner
>>> dropping the link with us, and the interface will be non-functional as
>>> far as the data path is concerned (similar to an isolation mode). This
>>> might warrant properly reporting that to user-space through e.g: a
>>> private IFF_* value maybe?
>> 
>> Hi Florian
>> 
>> I think a IFF_* value would be a good idea. We want to give the user
>> some indicate why they don't have working networking. ip link show
>> showing PHY-TEST-MODE would help.
> 
> IF_OPER_TESTING as defined in RFC 2863 looks like the correct way to
> signal that. I did a quick test and setting operstate to
> IFF_OPER_TESTING seems to correctly get reflected by iproute2/ifconfig
> which no longer see RUNNING though the interface is still UP. If we
> couple that with a proper phy_stop(), this would IMHO be consistent from
> an user experience perspective.
> 
> David, would that look reasonable to you?

Yes, it does.