Re: [PATCH 1/6] drivers: base: devres: Allow to release group on device release

[Lucas De Marchi]

On Thu, Feb 20, 2025 at 01:24:20PM +0100, Greg Kroah-Hartman wrote:
> On Wed, Feb 12, 2025 at 12:05:37PM -0800, Lucas De Marchi wrote:
> > When releasing a device, if the release action causes a group to be
> > released, a warning is emitted because it can't find the group. This
> > happens because devres_release_all() moves the entire list to a todo
> > list and also move the group markers. Considering r* normal resource
> > nodes and g1 a group resource node:
> >
> > 		    g1 -----------.
> > 		    v		  v
> > 	r1 -> r2 -> g1[0] -> r3-> g[1] -> r4
> >
> > After devres_release_all(), dev->devres_head becomes empty and the todo
> > list it iterates on becomes:
> >
> > 			       g1
> > 			       v
> > 	r1 -> r2 -> r3-> r4 -> g1[0]
> >
> > When a call to component_del() is made and takes down the aggregate
> > device, a warning like this happen:
> >
> > 	RIP: 0010:devres_release_group+0x362/0x530
> > 	...
> > 	Call Trace:
> > 	 <TASK>
> > 	 component_unbind+0x156/0x380
> > 	 component_unbind_all+0x1d0/0x270
> > 	 mei_component_master_unbind+0x28/0x80 [mei_hdcp]
> > 	 take_down_aggregate_device+0xc1/0x160
> > 	 component_del+0x1c6/0x3e0
> > 	 intel_hdcp_component_fini+0xf1/0x170 [xe]
> > 	 xe_display_fini+0x1e/0x40 [xe]
> >
> > Because the devres group corresponding to the hdcp component cannot be
> > found. Just ignore this corner case: if the dev->devres_head is empty
> > and the caller is trying to remove a group, it's likely in the process
> > of device cleanup so just ignore it instead of warning.
> >
> > Signed-off-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
> > ---
>
> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

Thanks. Is it ok to take these 3 through the drm tree or are you taking
it through yours?

Lucas De Marchi