[alsa-devel] [PATCH] ASoC: SOF: intel: Fix probe error without i915 graphics

[Kai Vehmanen]

Hey,

On Mon, 17 Feb 2020, Takashi Iwai wrote:

> On Mon, 17 Feb 2020 14:17:54 +0100, Kai Vehmanen wrote:
> >  snd_hdac_i915_exit() calls
> >    -> snd_hdac_acomp_exit(), which again calls
> >    -> component.c:component_master_del(dev, &hdac_component_master_ops);
> >    -> component.c:take_down_master()
> >    -> devres.c:devres_release_group(master->dev, NULL);
> > 
> > ...  now that is somewhat suprising. Basicly that goes on to release all 
> > devres resources for the hdac_bus device (not just those related to 
> > acomp!).
> 
> Does it really?  I thought it applies only to the group, and id=NULL
> indicating that it's a local group that was created with id=NULL (by
> address match).

at least in my tests, acomp_exit() ended up releasing a bunch of devres 
allocations made with devm_kzalloc() that had no relation to acomp. I 
noted that in devres.c:find_group(), docs say:

/* Find devres group with ID @id.  If @id is NULL, look for the latest. */
static struct devres_group * find_group(struct device *dev, void *id)

... I don't see how it would be limiting a local group.

Br, Kai