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Date: Mon, 5 May 2025 10:30:54 +0200
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: linux-kernel@vger.kernel.org
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH] clocksource/i8253: Acquire the lock disabled interrupts.
Message-ID: <20250505083054.l7eNRXnn@linutronix.de>
References: <20250404133116.p-XRWJXf@linutronix.de>
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In-Reply-To: <20250404133116.p-XRWJXf@linutronix.de>

On 2025-04-04 15:31:17 [+0200], To linux-kernel@vger.kernel.org wrote:
> On x86 during boot, clockevent_i8253_disable() can be invoked via
> x86_late_time_init -> hpet_time_init() -> pit_timer_init() which happens
> with enabled interrupts.
> If some of the old i8253 hardware is actually used then lockdep will
> notice that i8253_lock is used in hardirq context. This causes lockdep
> to complain because it observed the lock being acquired with enabled
> interrupts and in hardirq context.
> 
> Make clockevent_i8253_disable() acquire the lock with disabled
> interrupts.
> 
> Fixes: c8c4076723dac ("x86/timer: Skip PIT initialization on modern chipsets")
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

A gentle reminder.

Sebastian