From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: Reducing or removing direct map from xen (was Re:
 Ongoing/future speculative mitigation work)
Date: Wed, 20 Feb 2019 13:09:56 +0000
Message-ID: <20190220130956.tkhsmdojzdf4nc7x@zion.uk.xensource.com>
References: <e3219697-0759-39fc-2486-715cdec1ca9e@citrix.com>
 <20190124114455.eyke5dvkqsxhklav@zion.uk.xensource.com>
 <20190220122901.6kvc7ibyjo4uyzke@zion.uk.xensource.com>
 <20190220130052.b22syaca6cswc3pk@Air-de-Roger>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Return-path: <xen-devel-bounces@lists.xenproject.org>
Received: from us1-rack-dfw2.inumbo.com ([104.130.134.6])
 by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from
 <SRS0=RPnU=Q3=citrix.com=prvs=947cb6223=wei.liu2@srs-us1.protection.inumbo.net>)
 id 1gwRda-0008Hn-4M
 for xen-devel@lists.xenproject.org; Wed, 20 Feb 2019 13:10:10 +0000
Content-Disposition: inline
In-Reply-To: <20190220130052.b22syaca6cswc3pk@Air-de-Roger>
List-Unsubscribe: <https://lists.xenproject.org/mailman/options/xen-devel>,
 <mailto:xen-devel-request@lists.xenproject.org?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xenproject.org>
List-Help: <mailto:xen-devel-request@lists.xenproject.org?subject=help>
List-Subscribe: <https://lists.xenproject.org/mailman/listinfo/xen-devel>,
 <mailto:xen-devel-request@lists.xenproject.org?subject=subscribe>
Errors-To: xen-devel-bounces@lists.xenproject.org
Sender: "Xen-devel" <xen-devel-bounces@lists.xenproject.org>
To: Roger Pau =?iso-8859-1?Q?Monn=E9?= <roger.pau@citrix.com>
Cc: Martin Pohlack <mpohlack@amazon.de>, Julien Grall <julien.grall@arm.com>, Jan Beulich <JBeulich@suse.com>, Joao Martins <joao.m.martins@oracle.com>, Stefano Stabellini <sstabellini@kernel.org>, Daniel Kiper <daniel.kiper@oracle.com>, Marek Marczykowski <marmarek@invisiblethingslab.com>, Anthony Liguori <aliguori@amazon.com>, Xen-devel <xen-devel@lists.xenproject.org>, "Dannowski, Uwe" <uwed@amazon.de>, Lars Kurth <lars.kurth@citrix.com>, Konrad Wilk <konrad.wilk@oracle.com>, Ross Philipson <ross.philipson@oracle.com>, Dario Faggioli <dfaggioli@suse.com>, Matt Wilson <msw@amazon.com>, Boris Ostrovsky <boris.ostrovsky@oracle.com>, Juergen Gross <JGross@suse.com>, Sergey Dyasli <sergey.dyasli@citrix.com>, Wei Liu <wei.liu2@citrix.com>, George Dunlap <george.dunlap@eu.citrix.com>, Andrew Cooper <andrew.cooper3@citrix.com>, Mihai =?utf-8?B?RG9uyJt1?= <mdontu@bitdefender.com>
List-Id: xen-devel@lists.xenproject.org
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