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To: Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org
Cc: linux-tip-commits@vger.kernel.org, Mirsad Todorovac
 <mirsad.todorovac@alu.unizg.hr>, Sean Anderson <sean.anderson@seco.com>,
 x86@kernel.org
Subject: Re: [tip: timers/urgent] timekeeping: Use READ/WRITE_ONCE() for
 tick_do_timer_cpu
In-Reply-To: <ZhZKiKyXsgSeABvD@gmail.com>
References: <87cyqy7rt3.ffs@tglx>
 <171269748856.10875.3911619468870441338.tip-bot2@tip-bot2>
 <ZhZKiKyXsgSeABvD@gmail.com>
Date: Wed, 10 Apr 2024 16:54:34 +0200
Message-ID: <87y19l2rpx.ffs@tglx>
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On Wed, Apr 10 2024 at 10:15, Ingo Molnar wrote:
>> @@ -232,7 +233,7 @@ static void tick_setup_device(struct tick_device *td,
>>  						!tick_nohz_full_cpu(cpu)) {
>>  			tick_take_do_timer_from_boot();
>>  			tick_do_timer_boot_cpu = -1;
>> -			WARN_ON(tick_do_timer_cpu != cpu);
>> +			WARN_ON(READ_ON_ONCE(tick_do_timer_cpu) != cpu);
>
> So there's no such thing as READ_ON_ONCE() - I've amended the commit with 
> the fix below.

Can you hand me a brown paper bag please?