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Date: Wed, 9 Sep 2026 12:20:09 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Thomas Gleixner <tglx@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
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	Alexander Viro <viro@zeniv.linux.org.uk>,
	"Eric W. Biederman" <ebiederm@xmission.com>, stable@vger.kernel.org
Subject: Re: [patch V2 1/8] signal: Prevent exec() race
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In-Reply-To: <20260909095518.GL776954@noisy.programming.kicks-ass.net>

On Wed, Sep 09, 2026 at 11:55:19AM +0200, Peter Zijlstra wrote:
> D-E is a UNLOCK+LOCK hand-over, which is not quite the same as
> RELEASE+ACQUIRE. Specifically, we have:
> 
>   RELEASE+ACQUIRE: RCpc,  only the CPUs involved agree on the ordering
>   UNLOCK+LOCK:     RCtso, the hand-over is store-ordering
> 

For those that case: UNLOCK+LOCK is RCsc on all architectures except
Power.