Re: 6.9.0-rc2+ kernel hangs on boot (bisected, maybe LED related)

[Ben Greear <greearb@candelatech.com>]

On 5/2/24 00:19, Lee Jones wrote:
> On Tue, 23 Apr 2024, Linux regression tracking (Thorsten Leemhuis) wrote:
> 
>> On 23.04.24 11:06, Johannes Berg wrote:
>>> On Tue, 2024-04-23 at 11:00 +0200, Linux regression tracking (Thorsten
>>> Leemhuis) wrote:
>>>> On 16.04.24 08:17, Johannes Berg wrote:
>>>>> On Mon, 2024-04-15 at 13:37 -0700, Ben Greear wrote:
>>>>>>
>>>>>> Johannes, you had another suggestion: changing iwlwifi's request_module() to request_module_nowait() in
>>>>>> iwl_req_fw_callback()
>>>>>>
>>>>>> Is that still best thing to try in your opinion?
>>>>>
>>>>> I guess so, I don't have any better ideas so far anyway ...
>>>>
>>>> [adding the iwlwifi maintainer; thread starts here:
>>>> https://lore.kernel.org/lkml/30f757e3-73c5-5473-c1f8-328bab98fd7d@candelatech.com/
>>>>
>>>> ]
>>>>
>>>> Johannes, Miri, what's the status wrt to this regression? From here
>>>> things look somewhat stalled -- but maybe there was progress and I just
>>>> missed it.
>>>
>>> What do you want? It got bisected to an LED merge, but you ping _us_?
>>> Way to go ...
>>
>> Sorry, to me it sounded a bit like you had an idea for a fix and were
>> going to give it a try -- similar to how the maintainers for a r8169
>> driver and the igc driver provided fixes for bugs recent LED changes
>> exposed.
>>
>> But sure, you are right, in the end some LED change seems to have cause
>> this, so the duty to fix it lies in that field. Therefore:
>>
>> Lee, what's the status here to get this fixed before the final?
> 
> No idea.  Did you send a fix?

I sent what is probably just a work-around.  I also spent time bisecting and testing.
The problem appears to have come in with the LED related merge.  I think it is fair
to ask the LED folks to at least take a look at the lockdep debugging I posted.  It is
not fair to expect anyone that manages to find or track a bug to also fix it.

If someone has a different suggested fix than the hack I posted, I will be happy to
test.  On my system with lots of radios, it is 100% reproducible.
Maybe email me directly as I don't keep close watch on LKML.

Thanks,
Ben


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com