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X-powerpc-patch-notification: thanks
X-powerpc-patch-commit: 6262db7c088bbfc26480d10144cde70bbf077be3
In-Reply-To: <20160610035128.21087-1-boqun.feng@gmail.com>
To: Boqun Feng <boqun.feng@gmail.com>, linux-kernel@vger.kernel.org,
        linuxppc-dev@lists.ozlabs.org
From: Michael Ellerman <mpe@ellerman.id.au>
Cc: Peter Zijlstra <peterz@infradead.org>, Boqun Feng <boqun.feng@gmail.com>,
        Will Deacon <will.deacon@arm.com>, Alexander Graf <agraf@suse.de>,
        Paul Mackerras <paulus@samba.org>,
        "Suresh E. Warrier" <warrier@linux.vnet.ibm.com>,
        "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: Re: [v4] powerpc: spinlock: Fix spin_unlock_wait()
Message-Id: <3rYTRV50CZz9t0w@ozlabs.org>
Date: Tue, 21 Jun 2016 10:40:54 +1000 (AEST)
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On Fri, 2016-10-06 at 03:51:28 UTC, Boqun Feng wrote:
> There is an ordering issue with spin_unlock_wait() on powerpc, because
> the spin_lock primitive is an ACQUIRE and an ACQUIRE is only ordering
> the load part of the operation with memory operations following it.
...
> 
> Suggested-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
> Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
> Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
> [mpe: Inline the "nop" ll/sc loop and set EH=0, munge change log]
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/6262db7c088bbfc26480d10144

cheers