From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Durrant <Paul.Durrant@citrix.com>
Subject: Re: [PATCH 6/8] x86/emul: Support speculative MSR reads
Date: Mon, 5 Dec 2016 13:03:46 +0000
Message-ID: <10246a0e8c5440b59c4e394a436d928a@AMSPEX02CL03.citrite.net>
References: <1480932571-23547-1-git-send-email-andrew.cooper3@citrix.com>
 <1480932571-23547-7-git-send-email-andrew.cooper3@citrix.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Return-path: <xen-devel-bounces@lists.xen.org>
In-Reply-To: <1480932571-23547-7-git-send-email-andrew.cooper3@citrix.com>
Content-Language: en-US
List-Unsubscribe: <https://lists.xen.org/cgi-bin/mailman/options/xen-devel>,
 <mailto:xen-devel-request@lists.xen.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xen.org>
List-Help: <mailto:xen-devel-request@lists.xen.org?subject=help>
List-Subscribe: <https://lists.xen.org/cgi-bin/mailman/listinfo/xen-devel>,
 <mailto:xen-devel-request@lists.xen.org?subject=subscribe>
Errors-To: xen-devel-bounces@lists.xen.org
Sender: "Xen-devel" <xen-devel-bounces@lists.xen.org>
To: Xen-devel <xen-devel@lists.xen.org>
Cc: Andrew Cooper <Andrew.Cooper3@citrix.com>, Jan Beulich <JBeulich@suse.com>
List-Id: xen-devel@lists.xenproject.org
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