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Date:   Thu, 5 Apr 2018 16:56:50 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     Daniel Jordan <daniel.m.jordan@oracle.com>, parri.andrea@gmail.com,
        will.deacon@arm.com, boqun.feng@gmail.com, npiggin@gmail.com,
        dhowells@redhat.com, j.alglave@ucl.ac.uk, luc.maranget@inria.fr,
        paulmck@linux.vnet.ibm.com, akiyks@gmail.com,
        linux-kernel@vger.kernel.org,
        Steven Sistare <steven.sistare@oracle.com>,
        Pasha Tatashin <pasha.tatashin@oracle.com>
Subject: Re: Control dependency between prior load in while condition and
 later store?
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On Thu, Apr 05, 2018 at 10:35:22AM -0400, Alan Stern wrote:
> In this example, READ_ONCE() is in fact a volatile access, so we're 
> okay.

But our documentation clearly states a control-dep can only be from a
READ_ONCE() (or something stronger), right? So we should be good
irrespectively.