From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [Xen-devel] [PATCH 3/8] x86/xen/p2m: Replace ACCESS_ONCE with
 READ_ONCE
Date: Thu, 15 Jan 2015 10:43:40 +0000
Message-ID: <54B799DC.1050008@citrix.com>
References: <1421312314-72330-1-git-send-email-borntraeger@de.ibm.com> <1421312314-72330-4-git-send-email-borntraeger@de.ibm.com>
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Cc: <linux-arch@vger.kernel.org>, <kvm@vger.kernel.org>,
	<x86@kernel.org>, <kvm-ppc@vger.kernel.org>, <linux-mm@kvack.org>,
	<xen-devel@lists.xenproject.org>, <linuxppc-dev@lists.ozlabs.org>
To: Christian Borntraeger <borntraeger@de.ibm.com>,
	<linux-kernel@vger.kernel.org>
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On 15/01/15 08:58, Christian Borntraeger wrote:
> ACCESS_ONCE does not work reliably on non-scalar types. For
> example gcc 4.6 and 4.7 might remove the volatile tag for such
> accesses during the SRA (scalar replacement of aggregates) step
> (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145)
> 
> Change the p2m code to replace ACCESS_ONCE with READ_ONCE.

Acked-by: David Vrabel <david.vrabel@citrix.com>

Let me know if you want me to merge this via the Xen tree.

David