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From: Thomas Gleixner <tglx@linutronix.de>
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To: Haofeng Li <920484857@qq.com>, John Stultz <jstultz@google.com>
Cc: linux-kernel@vger.kernel.org, Stephen Boyd <sboyd@kernel.org>, Haofeng
 Li <13266079573@163.com>, Haofeng Li <lihaofeng@kylinos.cn>
Subject: Re: [PATCH] timekeeping: Move debug sleep time accounting outside
 spinlock
In-Reply-To: <tencent_6FBD7FB2B5EDA57B1481766C52482D033008@qq.com>
References: <tencent_6FBD7FB2B5EDA57B1481766C52482D033008@qq.com>
Date: Tue, 09 Sep 2025 13:46:21 +0200
Message-ID: <871pofx302.ffs@tglx>
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On Tue, Sep 09 2025 at 18:23, Haofeng Li wrote:
> From: Haofeng Li <lihaofeng@kylinos.cn>
>
> The function tk_debug_account_sleep_time() was called inside a spinlock
> in __timekeeping_inject_sleeptime(), which could lead to potential
> deadlocks, particularly when CONFIG_DEBUG_PM_SLEEP is enabled.

How so exactly?

I don't see how that would deadlock, but I might miss something. So
please explain it properly instead of handwaving about it.

Thanks,

        tglx