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=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MSGID_FROM_MTA_HEADER,SPF_HELO_NONE,SPF_PASS 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 4390BC4708F for ; Tue, 1 Jun 2021 17:25:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2231A613AE for ; Tue, 1 Jun 2021 17:25:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234009AbhFAR0o (ORCPT ); Tue, 1 Jun 2021 13:26:44 -0400 Received: from mail-bn8nam11on2078.outbound.protection.outlook.com ([40.107.236.78]:54808 "EHLO NAM11-BN8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231918AbhFAR0o (ORCPT ); Tue, 1 Jun 2021 13:26:44 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=V4P0X0tLdgT/+mpSJK6niXwlerCletI7zk7sVvweZXnk1RgqXtVwAY+zG4p5yjy/1T6sZLm3yRz/KGpnVvUAnzCiLj7R5hRwZ+yH+vU66Q3Logn2ccjxVX84U2pZgy2DeA0QVU+ZbbdlA9yc7xuobMl1xbSwqyFHF8KYG6o6Y2YSYEc+7Zn/o3kvqslUwggYmYnsx6eEwAbyKHkb5HezxdXzYlK8ehhCkVbOguOJe42rjIisurwh+MsRjSwovsxvPDjyjxnqYZ25cIkfbW4dujaNIqx5VPeAROryLRGsdkGRiIA4UpIDIz2nq0wabsUkw2475V+pw8FNDkl25ywShA== 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=l9Lgx7rdgZqul76FlIkn6rynKdbLSTMHJhIxTaIP5rU=; b=R6Tx+NYVmP0DpzWl0xdFvnopBrxQ9fh0hHXou7oNqMTJarIPbWMd9x9APdFTU+2Ldf7WrhXE7jC8PjOCDp+zPAlhM7553c3HwmVly/goaFR7HH7Fsd3cDWfSr2+9k1jmhf+7janj/CWSF5qD20eyG8fyui3nPlqL6VM3MWC9q2vI88QybnqrQ++CzTF3SGNp7DDqGVVSkk13sTGB6jSSGd+q1OO97vHi40269GR0t/kxwvMCfqQrRM0PNizkuslEZufwtkwGe4OlRG+zl1Jt540cV04viSCKb7aJ+/CY8yjxpkhOeZBZgLgswzPhFijI2252DAqxwiqtL/6yk51/fg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=l9Lgx7rdgZqul76FlIkn6rynKdbLSTMHJhIxTaIP5rU=; b=CghzaCf+Gx7BP/5FRQPfe47z9nxRlO4wbLjaPuUA4jkwYG00q0uTqQZ5oT2rLN6Jlz3ajZY6XHcPsdYiKTNk6aztJD1LPsgYRV/5HIuU9YzmagqyAfgQUd19coK+HQP0+/qMlLRNF5pepO/EwHAYJ3+a/Fc/BmfPyU3ysqt5NI3/gwujSv+cCIzz6w1KuF2eQ3Pwms8a/2pNWxKtGkCDb0Wk7sGxoDpGfLvIUjQ97t0goYPuqKWSMZH53V9LgRms2DtddsFE2oZRALh08kgj3FEaHVwr6/Y3xLlsroNOK/KZx846jx9bmpQa4AQlitKwEGZ05/xpOu3wUEhk9ZAjmA== Authentication-Results: linux.intel.com; dkim=none (message not signed) header.d=none;linux.intel.com; dmarc=none action=none header.from=nvidia.com; Received: from BL0PR12MB5506.namprd12.prod.outlook.com (2603:10b6:208:1cb::22) by BL1PR12MB5125.namprd12.prod.outlook.com (2603:10b6:208:309::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4173.20; Tue, 1 Jun 2021 17:25:01 +0000 Received: from BL0PR12MB5506.namprd12.prod.outlook.com ([fe80::3d51:a3b9:8611:684e]) by BL0PR12MB5506.namprd12.prod.outlook.com ([fe80::3d51:a3b9:8611:684e%7]) with mapi id 15.20.4173.030; Tue, 1 Jun 2021 17:25:01 +0000 Date: Tue, 1 Jun 2021 14:24:59 -0300 From: Jason Gunthorpe To: Lu Baolu Cc: Liu Yi L , Jean-Philippe Brucker , "Tian, Kevin" , "Jiang, Dave" , "Raj, Ashok" , "kvm@vger.kernel.org" , Jonathan Corbet , David Woodhouse , Jason Wang , LKML , Kirti Wankhede , "Alex Williamson (alex.williamson@redhat.com)" , "iommu@lists.linux-foundation.org" , Robin Murphy , David Gibson Subject: Re: [RFC] /dev/ioasid uAPI proposal Message-ID: <20210601172459.GJ1002214@nvidia.com> References: <20210528233649.GB3816344@nvidia.com> <20210531193157.5494e6c6@yiliu-dev> <20210531180911.GX1002214@nvidia.com> <6ca65628-1c0e-4ae3-6357-1493f993349e@linux.intel.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <6ca65628-1c0e-4ae3-6357-1493f993349e@linux.intel.com> X-Originating-IP: [47.55.113.94] X-ClientProxiedBy: MN2PR16CA0009.namprd16.prod.outlook.com (2603:10b6:208:134::22) To BL0PR12MB5506.namprd12.prod.outlook.com (2603:10b6:208:1cb::22) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from mlx.ziepe.ca (47.55.113.94) by MN2PR16CA0009.namprd16.prod.outlook.com (2603:10b6:208:134::22) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4173.20 via Frontend Transport; Tue, 1 Jun 2021 17:25:01 +0000 Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1lo88R-00HXVB-T4; Tue, 01 Jun 2021 14:24:59 -0300 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 01330da6-9441-4853-837b-08d925222fc3 X-MS-TrafficTypeDiagnostic: BL1PR12MB5125: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:7219; 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:BL0PR12MB5506.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(39860400002)(376002)(366004)(136003)(346002)(396003)(8936002)(66476007)(66946007)(86362001)(4744005)(8676002)(36756003)(7416002)(2616005)(5660300002)(9746002)(26005)(6916009)(83380400001)(1076003)(2906002)(426003)(53546011)(4326008)(54906003)(478600001)(66556008)(9786002)(33656002)(38100700002)(186003)(316002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?XaexVpdrElJId4XqzjDiqpWaoshDx8HcxjB+TKSAUn0GrTSjfMdYSV53nVWB?= =?us-ascii?Q?gFUE+Zt74TxeWsqyT5JpThKt0UfAa+Hzvs1SD8e5Lt6UEhcHvSXnPvCN03kH?= =?us-ascii?Q?7UEclIDuUSBQZPJcbZGRHSJphFnBtqeJ9kmyxyRXCEAXf0ccb9BSV3prvvwa?= =?us-ascii?Q?OliY8810aCA2aQKJIkUQym6yltMy8qUFlAeLiuVwRb1PqCw03euRfs78HYGK?= =?us-ascii?Q?z78XZyE5dEd9rRHwmZV4GfzydRPjejVyo4fav6+4yqD3KBvIpXYq956hePkj?= =?us-ascii?Q?e4UYP3V4lgZ3OQS62BFevXhMaStiUFWBhdKjEqmFyBco2qo4c+MlRmoeikji?= =?us-ascii?Q?8h9SOPIBlygg+N9OlIX0+FAy4pEDKl0VSEtWbLpVA5P65LgFHgTm62hcBHmh?= =?us-ascii?Q?16ByXRpLEfVwhduJ3wcNoSBVUdCdS0GZvvWE1iPSy9M7SjWTq5TWQ3P4Bzwp?= =?us-ascii?Q?vQgUIZ7F539pgyMM4R9LDdQGquXrHT0jy+Jk4kb6/BwzqI/2mTFO8evYJfgf?= =?us-ascii?Q?8zXlMYD9JWcgEoCVrChxBOV4fp+WLZZ49BBemZqRMTy1om6uYRqFG3JtHuLZ?= =?us-ascii?Q?snFBOqMpR9KQpt8RIM0AJixZ1aGGNnwFFt8QcKkatsSHdczowqxP4wQQXfrm?= =?us-ascii?Q?om8qOFyFPpWBAO5YHcA6ippYLXc0s40V7IeCvLUzPHc16DPH2lEA8h/oIbiS?= =?us-ascii?Q?2rRg5mYQ2KkiUAYEq0qwzyJpn5BZofqjDNrIiI78jwvs5u6MrWogRyehSLrH?= =?us-ascii?Q?iaa9AyYTQpPj+Z1HIckgLYgP4RX2a15aqiEGoH1TWTvmhVE0Aj2YKPQmlOhh?= =?us-ascii?Q?SqMqFw3M1QgblsQy5udwMuMsJR3/KHYQbLX6dKxquL09VKNC4p1QGrcIRbk9?= =?us-ascii?Q?vgIdHtXYpErVz2mk0LT9mcOV1n8DmIe+XMN7Z8G5siopJbQdUMsXt5YjJVWJ?= =?us-ascii?Q?PXtNOrpAnNp/3ip9ilttpOrlAFxGc2Ir2L+nU1oRPXTwvFCyReUuCCRDVIt/?= =?us-ascii?Q?WV89gDQIXhlJeRHxyIzrS4DmTliMeHQMOq09LsUVU5GnZ1lzy9fZ2UqcbtUf?= =?us-ascii?Q?lcFqHmHJ7Bgau6zaF/q5TKtTjaD05zXf4pz4YV60niI5vrIROKp4l2XmbMEe?= =?us-ascii?Q?b+HpXXyoG7yGqpGKvOTUEJepwqXvJ10rwpU/bSKSyYy++2++vfZZulKC2pEW?= =?us-ascii?Q?sp44Svw5+cZLjDTLaJnqvbtDhYF+WEH9Fm+++d8a3RNmu7aq896dG8Q1Y0bb?= =?us-ascii?Q?5UEzn1brWtTPdKdo/DPZSJBcXYf1Z7RAFwLOa1XM2t1596Ign/xm3VA7Vdk0?= =?us-ascii?Q?yfvbSSU5LlkOOtoRu7m3gIrj?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 01330da6-9441-4853-837b-08d925222fc3 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Jun 2021 17:25:01.1965 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: XujNGRw2qQWv5IQWZ9TaMBFPsy5qDP8hmMWP3SnSVckM7qKjRz1c6JPBaF/tyiSb X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5125 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Jun 01, 2021 at 11:08:53AM +0800, Lu Baolu wrote: > On 6/1/21 2:09 AM, Jason Gunthorpe wrote: > > > > device bind should fail if the device somehow isn't compatible with > > > > the scheme the user is tring to use. > > > yeah, I guess you mean to fail the device attach when the IOASID is a > > > nesting IOASID but the device is behind an iommu without nesting support. > > > right? > > Right.. > > Just want to confirm... > > Does this mean that we only support hardware nesting and don't want to > have soft nesting (shadowed page table in kernel) in IOASID? No, the uAPI presents a contract, if the kernel can fulfill the contract then it should be supported. If you want SW nesting then the kernel has to have the SW support for it or fail. At least for the purposes of document I wouldn't devle too much deeper into that question. Jason