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Date: Thu, 31 Oct 2024 10:44:35 +0100
From: Frederic Weisbecker <frederic@kernel.org>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel test robot <oliver.sang@intel.com>,
	Anna-Maria Behnsen <anna-maria@linutronix.de>,
	oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org
Subject: Re: timers: Add missing READ_ONCE() in __run_timer_base()
Message-ID: <ZyNRg/fAJKY2h9ql@lothringen>
References: <202410301205.ef8e9743-lkp@intel.com>
 <87a5emyqk0.ffs@tglx>
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In-Reply-To: <87a5emyqk0.ffs@tglx>

On Wed, Oct 30, 2024 at 08:53:51AM +0100, Thomas Gleixner wrote:
> __run_timer_base() checks base::next_expiry without holding
> base::lock. That can race with a remote CPU updating next_expiry under the
> lock. This is an intentional and harmless data race, but lacks a
> READ_ONCE(), so KCSAN complains about this.
> 
> Add the missing READ_ONCE(). All other places are covered already.
> 
> Fixes: 79f8b28e85f8 ("timers: Annotate possible non critical data race of next_expiry")
> Reported-by: kernel test robot <oliver.sang@intel.com>
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> Closes: https://lore.kernel.org/oe-lkp/202410301205.ef8e9743-lkp@intel.com

Reviewed-by: Frederic Weisbecker <frederic@kernel.org>