linux-kernel - Re: [PATCH v3 12/12] PM: EM: Use scope-based cleanup helper

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Message-ID: <04ca5584-b10e-465d-bbda-627b7f743ce9@kernel.org>
Date: Wed, 3 Sep 2025 08:11:12 +0200
From: Krzysztof Kozlowski <krzk@...nel.org>
To: Zihuan Zhang <zhangzihuan@...inos.cn>
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Subject: Re: [PATCH v3 12/12] PM: EM: Use scope-based cleanup helper

On 03/09/2025 04:12, Zihuan Zhang wrote:
>> You are not improving the source code here. This is not how to use
>>  __free() and you clearly do not understand the source code.
> 
> Sorry for the problem, policy should be assigned after cpumask_test_cpu().
> 
> I actually realized earlier that __free() only frees at the end of the variable’s lifetime. 
> I had suggested using a braced macro in cpufreq.h to allow immediate release after use, 
> but I understand the maintainer’s advice to “keep it simple” and will follow that.
> 
>> What's more, you did not use standard tools which would tell you this is
>> buggy and wrong.
> 
> Could you please let me know which standard tools you recommend for detecting such issues? 
> 
> I’d like to use them to avoid similar mistakes in the future.
All standard tools used for kernel development, sparse, smatch, clang,
coccinelle, see my talk from OSSE25.

Best regards,
Krzysztof