From patchwork Wed Jan 13 23:58:07 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 1426077 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=201602 header.b=WHrQo0Cp; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4DGPgG57dRz9sWP for ; Thu, 14 Jan 2021 11:04:10 +1100 (AEDT) Received: from localhost ([::1]:37068 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kzq7U-0003Sr-Kr for incoming@patchwork.ozlabs.org; Wed, 13 Jan 2021 19:04:08 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:36516) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kzq28-0007J8-2m; Wed, 13 Jan 2021 18:58:36 -0500 Received: from ozlabs.org ([2401:3900:2:1::2]:42003) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kzq25-0006fH-Ts; Wed, 13 Jan 2021 18:58:35 -0500 Received: by ozlabs.org (Postfix, from userid 1007) id 4DGPXR0hDnz9sX1; Thu, 14 Jan 2021 10:58:15 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1610582295; bh=XAe7Xx+YpNUPHcyhxW/cHKgMuEbgQoNbc1c/1ol/ah8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WHrQo0CpGmuAyajbdwUMx7qgn9Kr7iTclU8Uk3Goi3mgJfMWU9Nzex3+mn0SUfPIy xecXjdlhCJ1+mTEjl5fbqWu0n2T0lKHXdsVYiVX+tGC9y732Yulz2rRkTGA0sx0BfA V3fI8nw9ocNIb/PNhEsP0m0vgGwV8LbBBaXzbDoM= From: David Gibson To: brijesh.singh@amd.com, pair@us.ibm.com, dgilbert@redhat.com, pasic@linux.ibm.com, qemu-devel@nongnu.org Subject: [PATCH v7 09/13] confidential guest support: Update documentation Date: Thu, 14 Jan 2021 10:58:07 +1100 Message-Id: <20210113235811.1909610-10-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210113235811.1909610-1-david@gibson.dropbear.id.au> References: <20210113235811.1909610-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Received-SPF: pass client-ip=2401:3900:2:1::2; envelope-from=dgibson@ozlabs.org; helo=ozlabs.org X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.248, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: qemu-ppc@nongnu.org, thuth@redhat.com, Marcelo Tosatti , berrange@redhat.com, jun.nakajima@intel.com, kvm@vger.kernel.org, David Hildenbrand , cohuck@redhat.com, Richard Henderson , Greg Kurz , mdroth@linux.vnet.ibm.com, borntraeger@de.ibm.com, qemu-s390x@nongnu.org, frankja@linux.ibm.com, mst@redhat.com, pragyansri.pathi@intel.com, andi.kleen@intel.com, Paolo Bonzini , David Gibson , Eduardo Habkost Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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 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.