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Date: Thu, 9 Jun 2016 19:50:54 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: Boqun Feng <boqun.feng@gmail.com>, linuxppc-dev@lists.ozlabs.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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        Paul Mackerras <paulus@samba.org>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
        Will Deacon <will.deacon@arm.com>
Subject: Re: [PATCH v3] powerpc: spinlock: Fix spin_unlock_wait()
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On Thu, Jun 09, 2016 at 10:23:28PM +1000, Michael Ellerman wrote:
> Unfortunately the patch isn't 100%.

So what I'll do; since my patch is trying to ensure all implementations
of spin_unlock_wait() provide ACQUIRE semantics, and this patch does
indeed do so, is skip touching PPC entirely and hope this patch lands
before 4.8.