linux-kernel - Re: [PATCH v4 05/25] reboot: Warn if restart handler has duplicated priority

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Message-ID: <ad6c7d73-e7d3-4901-fd63-ef87eecd39a2@gmail.com>
Date:   Fri, 10 Dec 2021 22:44:41 +0300
From:   Dmitry Osipenko <digetx@...il.com>
To:     "Rafael J. Wysocki" <rafael@...nel.org>
Cc:     Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Thierry Reding <thierry.reding@...il.com>,
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Subject: Re: [PATCH v4 05/25] reboot: Warn if restart handler has duplicated
 priority

10.12.2021 22:42, Dmitry Osipenko пишет:
...
>>> There is no strong requirement for priorities to be unique, the reboot.c
>>> code will work properly.
>>
>> In which case adding the WARN() is not appropriate IMV.
>>
>> Also I've looked at the existing code and at least in some cases the
>> order in which the notifiers run doesn't matter.  I'm not sure what
>> the purpose of this patch is TBH.
> 
> The purpose is to let developer know that driver needs to be corrected.
> 
>>> The potential problem is on the user's side and the warning is intended
>>> to aid the user.
>>
>> Unless somebody has the panic_on_warn mentioned previously set and
>> really the user need not understand what the WARN() is about.  IOW,
>> WARN() helps developers, not users.
>>
>>> We can make it a strong requirement, but only after converting and
>>> testing all kernel drivers.
>>
>> Right.
>>
>>> I'll consider to add patches for that.
>>
>> But can you avoid adding more patches to this series?
> 
> I won't add more patches since such patches can be added only after
> completion of transition to the new API of the whole kernel.
> 

Thank you for the review.