On 19.07.2018 16:46, Andrew Lunn wrote:
>>> AFAIR there was a patch a while ago from Mellanox guys that was possibly
>>> extending the link notification with an error cause, this sounds like
>>> something that could be useful to report to user space somehow to help
>>> troubleshoot link down events.
>>>
>> Do you by chance have a reference to this patch? There's heavy development
>> on the Mellanox drivers with a lot of patches.
>
> Hi Heiner, Florian
>
> A general mechanism has been added to allow error messages to be
> reported via netlink sockets. I think wifi was the first to actually
> make use of it, since i think Johannes Berg did the core work, but
> other parts of the stack have also started using it.
>
I think you mean the devlink interface. With regard to nl80211 I'm aware
that it's used for communication between Wifi core and userspace tools /
daemons like hostapd and wpa_supplicant.
The devlink use case reminds me of swconfig for switch port configuration
under OpenWRT.
For our use case I think this is overkill, and I wonder what the
userspace tool would be that consumes our link down error info.
Heiner
> Just picking a commit at random, maybe not the best of examples:
>
> Fixes: 768075ebc238 ("nl80211: add a few extended error strings to key
> parsing")
>
> Andrew
>
