From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9F9A3C433DB for ; Thu, 14 Jan 2021 10:14:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C56D239FD for ; Thu, 14 Jan 2021 10:14:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728357AbhANKOM (ORCPT ); Thu, 14 Jan 2021 05:14:12 -0500 Received: from 8.mo51.mail-out.ovh.net ([46.105.45.231]:46432 "EHLO 8.mo51.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725989AbhANKOM (ORCPT ); Thu, 14 Jan 2021 05:14:12 -0500 X-Greylist: delayed 359 seconds by postgrey-1.27 at vger.kernel.org; Thu, 14 Jan 2021 05:14:10 EST Received: from mxplan5.mail.ovh.net (unknown [10.108.1.114]) by mo51.mail-out.ovh.net (Postfix) with ESMTPS id AD25625A6C9; Thu, 14 Jan 2021 11:07:28 +0100 (CET) Received: from kaod.org (37.59.142.103) by DAG8EX1.mxp5.local (172.16.2.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2044.4; Thu, 14 Jan 2021 11:07:27 +0100 Authentication-Results: garm.ovh; auth=pass (GARM-103G005a3ce3b89-2be7-4dd6-a28b-2751e61105ee, 0A7C53367AF3A9CD096E542ECC3C8B2C2D100868) smtp.auth=groug@kaod.org X-OVh-ClientIp: 82.253.208.248 Date: Thu, 14 Jan 2021 11:07:26 +0100 From: Greg Kurz To: David Gibson CC: , , , , , , "Richard Henderson" , Marcelo Tosatti , David Hildenbrand , , Marcel Apfelbaum , Paolo Bonzini , , , , , , Eduardo Habkost , , , , , Subject: Re: [PATCH v7 09/13] confidential guest support: Update documentation Message-ID: <20210114110726.189ee7fa@bahia.lan> In-Reply-To: <20210113235811.1909610-10-david@gibson.dropbear.id.au> References: <20210113235811.1909610-1-david@gibson.dropbear.id.au> <20210113235811.1909610-10-david@gibson.dropbear.id.au> X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.32; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [37.59.142.103] X-ClientProxiedBy: DAG4EX1.mxp5.local (172.16.2.31) To DAG8EX1.mxp5.local (172.16.2.71) X-Ovh-Tracer-GUID: 482ab6a6-6e0e-4269-8191-07b76130d318 X-Ovh-Tracer-Id: 1720375058512583068 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrgedukedrtdehgddtlecutefuodetggdotefrodftvfcurfhrohhfihhlvgemucfqggfjpdevjffgvefmvefgnecuuegrihhlohhuthemucehtddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjughrpeffhffvuffkjghfofggtgfgihesthejredtredtvdenucfhrhhomhepifhrvghgucfmuhhriicuoehgrhhouhhgsehkrghougdrohhrgheqnecuggftrfgrthhtvghrnhepfedutdeijeejveehkeeileetgfelteekteehtedtieefffevhffflefftdefleejnecukfhppedtrddtrddtrddtpdefjedrheelrddugedvrddutdefnecuvehluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmohguvgepshhmthhpqdhouhhtpdhhvghlohepmhigphhlrghnhedrmhgrihhlrdhovhhhrdhnvghtpdhinhgvtheptddrtddrtddrtddpmhgrihhlfhhrohhmpehgrhhouhhgsehkrghougdrohhrghdprhgtphhtthhopegrnhguihdrkhhlvggvnhesihhnthgvlhdrtghomh Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Thu, 14 Jan 2021 10:58:07 +1100 David Gibson wrote: > Now that we've implemented a generic machine option for configuring various > confidential guest support mechanisms: > 1. Update docs/amd-memory-encryption.txt to reference this rather than > the earlier SEV specific option > 2. Add a docs/confidential-guest-support.txt to cover the generalities of > the confidential guest support scheme > > Signed-off-by: David Gibson > --- LGTM Reviewed-by: Greg Kurz > docs/amd-memory-encryption.txt | 2 +- > docs/confidential-guest-support.txt | 43 +++++++++++++++++++++++++++++ > 2 files changed, 44 insertions(+), 1 deletion(-) > create mode 100644 docs/confidential-guest-support.txt > > diff --git a/docs/amd-memory-encryption.txt b/docs/amd-memory-encryption.txt > index 80b8eb00e9..145896aec7 100644 > --- a/docs/amd-memory-encryption.txt > +++ b/docs/amd-memory-encryption.txt > @@ -73,7 +73,7 @@ complete flow chart. > To launch a SEV guest > > # ${QEMU} \ > - -machine ...,memory-encryption=sev0 \ > + -machine ...,confidential-guest-support=sev0 \ > -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1 > > Debugging > diff --git a/docs/confidential-guest-support.txt b/docs/confidential-guest-support.txt > new file mode 100644 > index 0000000000..2790425b38 > --- /dev/null > +++ b/docs/confidential-guest-support.txt > @@ -0,0 +1,43 @@ > +Confidential Guest Support > +========================== > + > +Traditionally, hypervisors such as qemu have complete access to a > +guest's memory and other state, meaning that a compromised hypervisor > +can compromise any of its guests. A number of platforms have added > +mechanisms in hardware and/or firmware which give guests at least some > +protection from a compromised hypervisor. This is obviously > +especially desirable for public cloud environments. > + > +These mechanisms have different names and different modes of > +operation, but are often referred to as Secure Guests or Confidential > +Guests. We use the term "Confidential Guest Support" to distinguish > +this from other aspects of guest security (such as security against > +attacks from other guests, or from network sources). > + > +Running a Confidential Guest > +---------------------------- > + > +To run a confidential guest you need to add two command line parameters: > + > +1. Use "-object" to create a "confidential guest support" object. The > + type and parameters will vary with the specific mechanism to be > + used > +2. Set the "confidential-guest-support" machine parameter to the ID of > + the object from (1). > + > +Example (for AMD SEV):: > + > + qemu-system-x86_64 \ > + \ > + -machine ...,confidential-guest-support=sev0 \ > + -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=1 > + > +Supported mechanisms > +-------------------- > + > +Currently supported confidential guest mechanisms are: > + > +AMD Secure Encrypted Virtualization (SEV) > + docs/amd-memory-encryption.txt > + > +Other mechanisms may be supported in future.