Subject: Re: [net-next v4 10/12] ASoC: SOF: Introduce descriptors for SOF client

From: Pierre-Louis Bossart <[email-masked]>
Date: Sat, 23 May 2020 14:41:51 -0500

On 5/23/20 1:23 AM, Greg KH wrote:
> On Fri, May 22, 2020 at 09:29:57AM -0500, Pierre-Louis Bossart wrote:
>> This is not an hypothetical case, we've had this recurring problem when a
>> PCI device creates an audio card represented as a platform device. When the
>> card registration fails, typically due to configuration issues, the PCI
>> probe still completes.
> 
> Then fix that problem there.  The audio card should not be being created
> as a platform device, as that is not what it is.  And even if it was,
> the probe should not complete, it should clean up after itself and error
> out.

Did you mean 'the PCI probe should not complete and error out'?

If yes, that's yet another problem... During the PCI probe, we start a 
workqueue and return success to avoid blocking everything. And only 
'later' do we actually create the card. So that's two levels of probe 
that cannot report a failure. I didn't come up with this design, IIRC 
this is due to audio-DRM dependencies and it's been used for 10+ years.

> 
> That's not a driver core issue, sounds like a subsystem error handling
> issue that needs to be resolved.
> 
> thanks,
> 
> greg k-h
>