Re: [PATCH 3/4] drm/drm_ras: Add DRM RAS netlink error event notification

[Raag Jadav <raag.jadav@intel.com>]

On Wed, Apr 08, 2026 at 07:59:33PM +0530, Tauro, Riana wrote:
> On 3/25/2026 7:01 PM, Raag Jadav wrote:
> > On Wed, Mar 11, 2026 at 03:59:17PM +0530, Riana Tauro wrote:

...

> > > +Example: Listen to error events
> > > +
> > > +.. code-block:: bash
> > > +
> > > +    sudo ynl --family drm_ras --subscribe error-notify
> > > +    {'msg': {'error-id': 1, 'node-id': 1}, 'name': 'error-event'}
> > Can we also have error-name and node-name? I'd be pulling my hair off
> > if I need to remember all the ids.
> 
> Yeah makes sense. We can add the node_name, error_name.
> Adding device_name would also be more useful in the event.
> 
> @Rodrigo/@aravind thoughts?
> 
> > 
> > On that note, I think it'll be good to have them as part of request
> > attributes as an alternative to ids (also for existing commands) but
> > that can done as a follow up.
> > 
> We cannot use names as alternative because it won't work for multiple cards.
> example in xe: Suppose there are 2 cards and each has 2 nodes. We cannot
> query using node_name+error_name.
> Also most of the netlink implementations use id's as unique identifiers.
> 
> $ sudo ./cli.py --family drm_ras  --dump list-nodes
> [{'device-name': 'bdf_1', 'node-id': 0, 'node-name': 'correctable-errors',
> 'node-type': 'error-counter'},
>  {'device-name': 'bdf_1, 'node-id': 1, 'node-name': 'uncorrectable-errors',
> 'node-type': 'error-counter'},
>  {'device-name': 'bdf_2', 'node-id': 2, 'node-name': 'correctable-errors',
> 'node-type': 'error-counter'},
>  {'device-name': 'bdf_2', 'node-id': 3, 'node-name': 'uncorrectable-errors',
> 'node-type': 'error-counter'}]

This means they don't persist the user needs to figures out all the ids before
anything can happen. In device node world we have /dev/dri/by-path/<bdf> which
makes it much easier.

Also, I'm not much informed about the history and it's still unclear to me what
problem did netlink solve here that cannot be solved by anything else? But we're
too late for that discussion, and again, not my call.

> > Also, what if I have multiple devices with multiple nodes. Do they need
> > separate subscription?
> > 
> No, we subscribe only to the group not the nodes. In this case the group is
> 'error-notify'
> 
> $ sudo ./cli.py --family drm_ras --subscribe error-notify
> {'msg': {'error-id': 1, 'node-id': 1}, 'name': 'error-event'}
> {'msg': {'error-id': 1, 'node-id': 3}, 'name': 'error-event'}

Hm, perhaps I need to spend some time wrapping my head around the new concept.
Let's catch up sometime this week.

Raag