Crash in acpi_ns_validate_handle triggered by soundwire on Linux 5.10

[Pierre-Louis Bossart]

On 1/27/21 1:18 PM, Marcin Ślusarz wrote:
> śr., 27 sty 2021 o 18:28 Pierre-Louis Bossart
> <pierre-louis.bossart at linux.intel.com> napisał(a):
>>> Weird, I can't reproduce this problem with my self-compiled kernel :/
>>> I don't even see soundwire modules loaded in. Manually loading them of course
>>> doesn't do much.
>>>
>>> Previously I could boot into the "faulty" kernel by using "recovery mode", but
>>> I can't do that anymore - it crashes too.
>>>
>>> Maybe there's some kind of race and this bug depends on some specific
>>> ordering of events?
>>
>> missing Kconfig?
>> You need CONFIG_SOUNDWIRE and CONFIG_SND_SOC_SOF_INTEL_SOUNDWIRE
>> selected to enter this sdw_intel_acpi_scan() routine.
> 
> It was a PEBKAC, but a slightly different one. I won't bore you with
> (embarrassing) details ;).
> 
> I reproduced the problem, tested both your and Rafael's patches
> and the kernel still crashes, with the same stack trace.
> (Yes, I'm sure I booted the right kernel :)
> 
> Why "recovery mode" stopped working (or worked previously) is still a mystery.

ok, well if you have a consistent failure that's better to some extent.

Maybe a bit of explanations of what this routine tries to do:
when SoundWire is enabled in a system, we need to have the following 
pattern in the DSDT