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From: Thomas Gleixner <tglx@linutronix.de>
To: Byungchul Park <byungchul@sk.com>, linux-kernel@vger.kernel.org
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Subject: Re: [PATCH v11 14/26] locking/lockdep, cpu/hotplus: Use a weaker
 annotation in AP thread
In-Reply-To: <20240124115938.80132-15-byungchul@sk.com>
References: <20240124115938.80132-1-byungchul@sk.com>
 <20240124115938.80132-15-byungchul@sk.com>
Date: Fri, 26 Jan 2024 18:30:02 +0100
Message-ID: <87il3ggfz9.ffs@tglx>
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On Wed, Jan 24 2024 at 20:59, Byungchul Park wrote:

Why is lockdep in the subsystem prefix here? You are changing the CPU
hotplug (not hotplus) code, right?

> cb92173d1f0 ("locking/lockdep, cpu/hotplug: Annotate AP thread") was
> introduced to make lockdep_assert_cpus_held() work in AP thread.
>
> However, the annotation is too strong for that purpose. We don't have to
> use more than try lock annotation for that.

This lacks a proper explanation why this is too strong.

> Furthermore, now that Dept was introduced, false positive alarms was
> reported by that. Replaced it with try lock annotation.

I still have zero idea what this is about.

Thanks,

        tglx