Re: New kernel warning after updating from LTS 5.15.110 to 5.15.112 (and 5.15.113)

From: Chris Packham
Date: Tue Jun 06 2023 - 23:23:19 EST


Hi Lino,

On 7/06/23 13:43, Lino Sanfilippo wrote:
> Hi Bagas, hi Chris
>
> On 06.06.23 04:00, Bagas Sanjaya wrote:
>
>> On Tue, Jun 06, 2023 at 01:41:01AM +0000, Chris Packham wrote:
>>> Bisecting between v5.15.110 and v5.15.112 points to
>>>
>>> 51162b05a44cb5d98fb0ae2519a860910a47fd4b is the first bad commit
>> Thanks for the bisection.
>>
>> Lino, it looks like this regression is caused by (backported) commit of yours.
>> Would you like to take a look on it?
>>
> Before commit 51162b05a44c interrupt activation has failed since the concerning register was accessed
> without holding the required locality.
>
> Now with the commit applied the activation is successful and the interrupt handler is called as soon
> as an interrupt fires. However the handler runs in interrupt context while the register accesses
> are done via SPI which involves the SPI bus_lock_mutex. Calling the (sleepable) SPI functions in
> interrupt context results in the observed warning.
>
> To fix this additionally upstream commit 0c7e66e5fd69 ("tpm, tpm_tis: Request threaded interrupt handler") is
> required, since it ensures that the handler runs in process context.
>
> Note that even with this commit interrupts will eventually be disabled since the test for interrupts
> still fails (for the test to succeed at least upstream commit e644b2f498d2 "tpm, tpm_tis: Enable interrupt test"
> would be required).
>
> Chris, could you test again with commit 0c7e66e5fd69 additionally applied and confirm that the warning is gone?

Yes with 0c7e66e5fd69 cherry-picked on top the warning goes away. Adding
e644b2f498d2 doesn't seem to change anything (still reports that
interrupts aren't working) but that's the same as the latest mainline on
this hardware.