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

From: Dmitry Osipenko <digetx@gmail.com>
To: "Rafael J. Wysocki" <rafael@kernel.org>,
	"Michał Mirosław" <mirq-linux@rere.qmqm.pl>
Cc: Thierry Reding <thierry.reding@gmail.com>,
	Jonathan Hunter <jonathanh@nvidia.com>,
	Russell King <linux@armlinux.org.uk>,
	Catalin Marinas <catalin.marinas@arm.com>,
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	Geert Uytterhoeven <geert@linux-m68k.org>,
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Subject: Re: [PATCH v4 05/25] reboot: Warn if restart handler has duplicated priority
Date: Fri, 10 Dec 2021 22:49:47 +0300	[thread overview]
Message-ID: <7875d10b-0d9b-ca29-668b-630ea3650fd0@gmail.com> (raw)
In-Reply-To: <ad6c7d73-e7d3-4901-fd63-ef87eecd39a2@gmail.com>

10.12.2021 22:44, Dmitry Osipenko пишет:
> 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.
> 

I meant you, Rafael, and Michał, just in case :)