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=-7.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 C770EC433DB for ; Thu, 25 Feb 2021 18:19:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E97C64F27 for ; Thu, 25 Feb 2021 18:19:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232008AbhBYSTS (ORCPT ); Thu, 25 Feb 2021 13:19:18 -0500 Received: from mail-dm6nam11on2078.outbound.protection.outlook.com ([40.107.223.78]:15520 "EHLO NAM11-DM6-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S230166AbhBYSTM (ORCPT ); Thu, 25 Feb 2021 13:19:12 -0500 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=DUVDd/GpBWkDiuG/ZoNE15FXe9DJwPLqnrBGv+r8IL6UAy2PJlSd0o+ZD8lqtyLuyVg5HwxtqFT1xgFEYlnti08g26YKh8toEyWH9SV/6t8AUJLvB0gbBgbAtVSaY98dsIZH0yzcUast+9FHevpbZLpAE/QINcVruWN6MGsUK8ucuRGaQ8vb7JAHrHl1Tzns387CZxYcE8G4Rxb7RPcQ1bGRNWSFwGhw2/mznTDJ/FwT5CmBnk8ZUPz3ws8SsUby1FYubYdZjWK9faCPhViSBZzVI6DJTZTrUR0mOUc48/KpkaRYRI4Et8IjRpvzvrYgRT31k4T9llGit4x+VimDXA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=9gGDzg95XZhyKhDNkAFCXWMKwWqVBfl28tDw3rcfV8M=; b=Tb0zBaGS7gmzNVJVGtVOiOD9eAyBcyk6Li9iL+xpt+iz47cgOf/RNoo/7LMwJJPageM+wAFIJuXxTS+hHDbQAuXyGKxK49UDJdfZIgFCUJzogbfZhTW3EywqwdVv3rLeMlPyk6e2fakM0Fhe+gJL77et63xwZe95QM55akMgvI1taJNcmiWAjRoyHDq/n/Ugn6tLnhaaSbo6hdoNYY568Mr9yltJFXihj0RzuVL8bb6NToQ5F5n7b8T9Hv9GWwcMabHMLIVJsAZPuYojbKip4ZVHiALpR8+fg4zFRr5JAMLI7NQclhSLfRVRZQTg4t63HFvm1hrGkg1wNMVLZC+iHA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=9gGDzg95XZhyKhDNkAFCXWMKwWqVBfl28tDw3rcfV8M=; b=kF5qPiUk9U38LZfGHU1Qh+kJNx5XpCUZzNE6d7BJyTA71C40WixImEPsnVaCtoUC1rPLEwS1scwRXtIEisH8S5gNPeF9sSdc+SZbGuvGTn79gSB/c9sAeTuMQtY8VwGBJwYwv785eoeVEi9fVTMH9+jldGZ3FQ1uIAbCYczuSek= Authentication-Results: HansenPartnership.com; dkim=none (message not signed) header.d=none;HansenPartnership.com; dmarc=none action=none header.from=amd.com; Received: from SN6PR12MB2767.namprd12.prod.outlook.com (2603:10b6:805:75::23) by SN6PR12MB2685.namprd12.prod.outlook.com (2603:10b6:805:67::33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3846.34; Thu, 25 Feb 2021 18:18:18 +0000 Received: from SN6PR12MB2767.namprd12.prod.outlook.com ([fe80::24bb:3e53:c95e:cb8e]) by SN6PR12MB2767.namprd12.prod.outlook.com ([fe80::24bb:3e53:c95e:cb8e%7]) with mapi id 15.20.3890.020; Thu, 25 Feb 2021 18:18:18 +0000 Date: Thu, 25 Feb 2021 18:18:12 +0000 From: Ashish Kalra To: James Bottomley Cc: natet@google.com, brijesh.singh@amd.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, pbonzini@redhat.com, rientjes@google.com, seanjc@google.com, srutherford@google.com, thomas.lendacky@amd.com, x86@kernel.org, Tobin Feldman-Fitzthum , DOV MURIK Subject: Re: [RFC] KVM: x86: Support KVM VMs sharing SEV context Message-ID: <20210225181812.GA5046@ashkalra_ubuntu_server> References: <20210224085915.28751-1-natet@google.com> <7cb132ce522728f7689618832a65e31e37788201.camel@HansenPartnership.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <7cb132ce522728f7689618832a65e31e37788201.camel@HansenPartnership.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Originating-IP: [165.204.77.1] X-ClientProxiedBy: SA9PR13CA0087.namprd13.prod.outlook.com (2603:10b6:806:23::32) To SN6PR12MB2767.namprd12.prod.outlook.com (2603:10b6:805:75::23) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from ashkalra_ubuntu_server (165.204.77.1) by SA9PR13CA0087.namprd13.prod.outlook.com (2603:10b6:806:23::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3890.12 via Frontend Transport; Thu, 25 Feb 2021 18:18:18 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: d4632d10-529e-4b34-78f7-08d8d9b9b9ef X-MS-TrafficTypeDiagnostic: SN6PR12MB2685: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8882; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SN6PR12MB2767.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(39860400002)(136003)(376002)(346002)(396003)(366004)(478600001)(33716001)(7416002)(66476007)(66556008)(54906003)(9686003)(33656002)(55016002)(6496006)(316002)(66946007)(44832011)(4744005)(6666004)(5660300002)(8676002)(16526019)(186003)(86362001)(2906002)(4326008)(52116002)(6916009)(956004)(1076003)(8936002)(26005);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?kZ7xk2Lmd/+JcR2b141okrYC3U9rq7lElAVjWUjAeuN0OiCLhlor/tWe8uHm?= =?us-ascii?Q?p96ztWstPxBoXRD5f9l7Vk0yxb23q8jPiHZh/h3hP2pyCjPD+eqB77IPZVDx?= =?us-ascii?Q?GldzJf80HQQU8VeVFI7EQiUQArTk3lGjGfV5AunyjIHSicYhYg1ESXoYEiI2?= =?us-ascii?Q?KDc8ufptn9CEynbZ6XF4WICf2fC5wQx3K4snRweN4Z1Hv+gRAxgEXB0zetlY?= =?us-ascii?Q?O6xmZIvw97ZmKlyDvoMO5LechRixE6TA6jq4x9PP0nmG1+8spCo8/l/2usVd?= =?us-ascii?Q?ttfktrTUnVOOKJ0ZObzU38WWcCv2vbtL59v941MUCn0AfESUgW7ttjknPZ23?= =?us-ascii?Q?FV4itzd1QRalTVp/eegJ1xmfEddsMVkCYEVw+0HAfqc5YT6reBgCep3bS0qs?= =?us-ascii?Q?lrii2OIaPiiz3xfCIq0c1DmCB0UJKVXMzIcusVHoIpuJRp3IeLqcJKsLU1ol?= =?us-ascii?Q?2xo0lOT6x/yKWFzga8aelFE+YKmykE2vMTS7untCxRsblSwFistJ7Mcgvf+X?= =?us-ascii?Q?Njh33MBwmbae3V/NSuWVD48CP83mtgIyV3KHZL4BfdHNe+ywpdztzhx1LLxo?= =?us-ascii?Q?3gnaW0dYqBygZNQFG/XxXLGh2PlxE4RPAT52eB37yWQC6XmRCXaqil8BzhV1?= =?us-ascii?Q?ZKaOl0HOXQ3ZbQdaIsTR0U5mZIha3vDrGEzt3WYKX4UJdNNHJBtlJ+t919jT?= =?us-ascii?Q?PW38f7iMnbimBQZwIm5u4yoArRkGJ+llsrEYOLO+pdIGAcEMGkKEPVOd7Nyc?= =?us-ascii?Q?4VSB6BSJ20ZKwbTHGRn6WMZva71ifUSbBKjgrpYXGDTnGTAoWd9HKuWtJx2p?= =?us-ascii?Q?JtoFpG/GRxDQYg0aSiQwrG7ABIn7U/RWNFFE/pvumHOEwZziUyY20iaObFbh?= =?us-ascii?Q?Z98td8/96naAR6+k0iJqK//aGCh8V5G0qQ/7z3ytOH35mkn9VCSrr1/3fOmn?= =?us-ascii?Q?qmBf2x5Pp5nppQ7nLrEP4rudZ03XmY7E7PEj2bn3ozvmmvLIdgW2XQZcpbK/?= =?us-ascii?Q?uUkU1o06yw7JIp/r5aPDjijILv8NpDPHCo+rAbET8YL4HnI870202peAIZB0?= =?us-ascii?Q?mNjHWZPAwmXff4tF4sLv7AQE0/h55tQAEJJLRaSNrxMneJ7AH7LcBKn4Me3/?= =?us-ascii?Q?FmAJ8nQJZMuTftomrjS4TGJe2oTt5fiM5jAWTKftidfSvGPNWNdZ7Fcyry6E?= =?us-ascii?Q?Z+0bgG8tbv2L+yctMR0fovofUvmMcVdh+lCpvsuAj/n9/IebGJ268ur5ulrz?= =?us-ascii?Q?5bf1G3Et3r7VgLT4VI5TVhSq0xqst3uj3B7JKk2Q590cB8EkHQhVpYsdYiWh?= =?us-ascii?Q?dP8u3zwWpGEZkAd1q1u3+oDW?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: d4632d10-529e-4b34-78f7-08d8d9b9b9ef X-MS-Exchange-CrossTenant-AuthSource: SN6PR12MB2767.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Feb 2021 18:18:18.5990 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: QrGWbUWgjy2xuPK8b4tODZnvM2df1J0ZlDuMDVvtq4FZVx/h4t3wZhoUychd+jKbc/vYbQAdh+alXvH/Ta9rOw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN6PR12MB2685 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >> > For additional context, we need a Migration Helper because SEV PSP >> > migration is far too slow for our live migration on its own. Using an >> > in-guest migrator lets us speed this up significantly. >> >> We have the same problem here at IBM, hence the RFC referred to above. >> I do believe that some of these alternative SEV live migration support or Migration helper (MH) solutions will still use SEV PSP migration for migrating the MH itself, therefore the SEV live migration patches (currently v10 posted upstream) still make sense and will be used. Thanks, Ashish