Re: [PATCH 2/4] soc: qcom: icc-bwmon: Allow for interrupts to be shared across instances

[Sibi Sankar <quic_sibis@quicinc.com>]

On 6/14/24 13:54, Krzysztof Kozlowski wrote:
> On 13/06/2024 19:02, Sibi Sankar wrote:
>>
>>
>> On 6/4/24 12:16, Krzysztof Kozlowski wrote:
>>> On 04/06/2024 03:11, Sibi Sankar wrote:
>>>> The multiple BWMONv4 instances available on the X1E80100 SoC use the
>>>> same interrupt number. Mark them are shared to allow for re-use across
>>>> instances.
>>
>> Hey Krzysztof,
>>
>> Thanks for taking time to review the series :)
>>
>>>
>>> Would be nice if you also mention you checked that it is safe to have
>>> both devm and shared interrupts (so you investigated possibility of race
>>> on exit path).
>>
>> I didn't see any problems with devm being used with SHARED when I posted
>> it out. After your review comments I went back again to vett the exit
>> path for races and ran into an pre-existing splat [1] but the bwmon
>> instances work as expected on module removal/re-insertion.
> 
> Using devm and shared interrupts is in general sign of possible race
> issues and should be avoided. Just "not seeing problems" is not an
> argument for me, to be honest.

Didn't I go further and say I got it tested though? Also can you
elaborate on what race do you think the bwmon will hit rather than
being too generic about it?

-Sibi

> 
> Best regards,
> Krzysztof
>