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[209.132.180.67]) by mx.google.com with ESMTP id h2si296639pgc.330.2018.02.19.15.53.53; Mon, 19 Feb 2018 15:54:10 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=vt.edu Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932261AbeBSXxP (ORCPT + 99 others); Mon, 19 Feb 2018 18:53:15 -0500 Received: from outbound.smtp.vt.edu ([198.82.183.121]:56916 "EHLO omr1.cc.vt.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S932245AbeBSXxN (ORCPT ); Mon, 19 Feb 2018 18:53:13 -0500 Received: from mr3.cc.vt.edu (mr3.cc.ipv6.vt.edu [IPv6:2607:b400:92:8500:0:7f:b804:6b0a]) by omr1.cc.vt.edu (8.14.4/8.14.4) with ESMTP id w1JNrDeY022163 for ; Mon, 19 Feb 2018 18:53:13 -0500 Received: from mail-qk0-f198.google.com (mail-qk0-f198.google.com [209.85.220.198]) by mr3.cc.vt.edu (8.14.7/8.14.7) with ESMTP id w1JNr8Pn008752 for ; Mon, 19 Feb 2018 18:53:13 -0500 Received: by mail-qk0-f198.google.com with SMTP id y81so6475533qka.23 for ; Mon, 19 Feb 2018 15:53:13 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:in-reply-to:references :mime-version:content-transfer-encoding:date:message-id; bh=kjDgOGyIdHtVcG/rHIQqDBRPm0j9osFkUv/NAg5XnOk=; b=jVJVB/CS/FXBHOGVYlvcLBHzzOp3UpMlcZ8CLc/HhwWuD1Ap/ZEuxHZIUCVarr5ZEM xU93NL5RJ5H7I6jTBi6StcvVYrPlTfyQt6EGs6wsytAJwts6kuJ8DjUG6jBrvY429uqO mBDE6E6QmPPzl/Y14cKMuFwGVhEXxHf6DxpzTp2hP/DUGlYBeWnCRUnRkx9ynKSJNQyt l48hMgI18S3jXQvnx2aFlwLVF5GLWAx+r5+Y5n7HxGheceT0PNfYFoaY+TwiHyylxSN0 H+upQcinVYSbENdEG6/KfeHXYqIgiOU8o4e+LdSPw5In1VecTwQaj2e/6JqqvJ02tVq8 ldfQ== X-Gm-Message-State: APf1xPBi6FIuiE1E7QVPYXfqJ8PxJJs4IcLVycPR4dLT9w/PCHWr1NQQ xO7QHGvZSfbIcJPztGikhi0GvgD+6GRTSP6nVp3oJqP9VuLQpTIfrCLAmQ70FLOdS+ZaUVy9Ec9 qOU89l3D75zY8AJeWput2rmzHxOOySr/h1OM= X-Received: by 10.200.11.13 with SMTP id e13mr28050628qti.340.1519084388121; Mon, 19 Feb 2018 15:53:08 -0800 (PST) X-Received: by 10.200.11.13 with SMTP id e13mr28050615qti.340.1519084387847; Mon, 19 Feb 2018 15:53:07 -0800 (PST) Received: from turing-police.cc.vt.edu ([2601:5c0:c001:4342:dc2f:c781:134b:4d19]) by smtp.gmail.com with ESMTPSA id y27sm8217541qtc.85.2018.02.19.15.53.05 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 19 Feb 2018 15:53:06 -0800 (PST) From: valdis.kletnieks@vt.edu X-Google-Original-From: Valdis.Kletnieks@vt.edu X-Mailer: exmh version 2.8.0 04/21/2017 with nmh-1.7+dev To: "Van De Ven, Arjan" Cc: Jon Masters , David Woodhouse , Paolo Bonzini , "tglx@linutronix.de" , "x86@kernel.org" , "kvm@vger.kernel.org" , "torvalds@linux-foundation.org" , "linux-kernel@vger.kernel.org" , "Hansen, Dave" , Ingo Molnar Subject: Re: [PATCH 2/2] x86/speculation: Support "Enhanced IBRS" on future CPUs In-Reply-To: <0575AF4FD06DD142AD198903C74E1CC87A61923C@ORSMSX103.amr.corp.intel.com> References: <1518449255-2182-1-git-send-email-dwmw@amazon.co.uk> <1518449255-2182-2-git-send-email-dwmw@amazon.co.uk> <7e2e5ad1-49b6-1fdb-4a62-8ad6aefc30a0@redhat.com> <1518509708.12890.33.camel@infradead.org> <27c85759-e662-d281-f8a0-0a80ca8ee18f@redhat.com> <1518517262.12890.43.camel@infradead.org> <1518518198.12890.48.camel@infradead.org> <02bd3fdd-1b73-6cab-fb09-38ba933396bd@redhat.com> <1518775136.7876.13.camel@infradead.org> <75287047-77a0-e0ff-c2e8-61c81641251e@redhat.com> <1518776517.7876.21.camel@infradead.org> <1518783021.7876.34.camel@infradead.org> <4882860e-23c5-75b3-ac02-c700f615156e@jonmasters.org> <0575AF4FD06DD142AD198903C74E1CC87A61923C@ORSMSX103.amr.corp.intel.com> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1519084385_3347P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Mon, 19 Feb 2018 18:53:05 -0500 Message-ID: <10373.1519084385@turing-police.cc.vt.edu> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --==_Exmh_1519084385_3347P Content-Type: text/plain; charset=us-ascii On Mon, 19 Feb 2018 23:42:24 +0000, "Van De Ven, Arjan" said: > the guest is not the problem; guests obviously will already honor if Enhanced > IBRS is enumerated. The problem is mixed migration pools where the hypervisor > may need to decide to not pass this enumeration through to the guest. For bonus points: What should happen to a VM that is live migrated from one hypervisor to another, and the hypervisors have different IBRS support? --==_Exmh_1519084385_3347P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Comment: Exmh version 2.8.0 04/21/2017 iQEVAwUBWotjYY0DS38y7CIcAQKk7wf7BvI+Z/7zK+ZZpj4lSNIdrdUjyEg7mn0R Vew6NFaLpP/G4ZeJEd70wG/D29GtKWlNKWbgV7nhNusSHxZVddaOx3elXtWHXSW9 2zJveZ5FVzfan/FwGVITg8egtvnyazKBTmrBOEBQFyvgdbSgnLqbKu0kcKet8Yaf GBQVd1DvISfLWtEAA1kPj4EDMz5Nhsspr75o9zSH4lelp+OkYHASUvYHlSMpWEK5 SBachW8j1t/gsoIaZ+7aqNLt5Xe+C3fPcajQtf55l0IV/j6V1+ziCcGMTouNs3en 3sK8MmeWOCYVaf43T7YbWSH7lBnS5oaKVzZwtK+UYs8Kqe4yhc6z6w== =bDvg -----END PGP SIGNATURE----- --==_Exmh_1519084385_3347P--