Re: [patch net-next v2 1/3] net: devlink: allow to change namespaces

[Jiri Pirko <jiri@resnulli.us>]

Wed, Jul 31, 2019 at 09:58:10PM CEST, dsahern@gmail.com wrote:
>On 7/31/19 1:46 PM, David Ahern wrote:
>> On 7/31/19 1:45 PM, Jiri Pirko wrote:
>>>> check. e.g., what happens if a resource controller has been configured
>>>> for the devlink instance and it is moved to a namespace whose existing
>>>> config exceeds those limits?
>>>
>>> It's moved with all the values. The whole instance is moved.
>>>
>> 
>> The values are moved, but the FIB in a namespace could already contain
>> more routes than the devlink instance allows.
>> 
>
>From a quick test your recent refactoring to netdevsim broke the
>resource controller. It was, and is intended to be, per network namespace.

unifying devlink instances with network namespace in netdevsim was
really odd. Netdevsim is also a device, like any other. With other
devices, you do not do this so I don't see why to do this with netdevsim.

Now you create netdevsim instance in sysfs, there is proper bus probe
mechanism done, there is a devlink instance created for this device,
there are netdevices and devlink ports created. Same as for the real
hardware.

Honestly, creating a devlink instance per-network namespace
automagically, no relation to netdevsim devices, that is simply wrong.
There should be always 1:1 relationshin between a device and devlink
instance.