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Tsirkin" , Nicolin Chen , Niklas Schnelle , Shameerali Kolothum Thodi , "Liu, Yi L" , Keqian Zhu Subject: Re: [PATCH v3 14/15] iommufd: vfio container FD ioctl compatibility Message-ID: References: <0-v3-402a7d6459de+24b-iommufd_jgg@nvidia.com> <14-v3-402a7d6459de+24b-iommufd_jgg@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BLAPR03CA0144.namprd03.prod.outlook.com (2603:10b6:208:32e::29) To LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5869:EE_|IA0PR12MB7774:EE_ X-MS-Office365-Filtering-Correlation-Id: c9d22f7c-3c70-47a9-18ee-08dac11d837e X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 4ZvvuL4QVWy48BokVThp1P0OBqV5yiyMIw1RLuGQHbzCmleCWb+S9v/YvdNixRZo/gcCfYlHHk5kVxlqKEF6foCdYESUf4eqs2ApCvnHtgCkRc0zJF6QTCiPNnzaVSe7ifY7SXsKBnR+aC7ZuOT34pGcecsY3BpZo5NZw7vfC2ZOa3I1lVPUg/GlTf66fpwNt6WeJoHdZXUb0Td8dTHZVUd+UlvOL9PCqZ37d0VS62fkaM/ft6FHh14l8KdvQOwy3HMa2q1DTO6E9NYrkb5mPa0xfXmCyW5SqE/tD0VBU+qmLgFEbIvGoSlT4y+gz+DsN23940YA4rj2J3SRNe26KwvPi9CTcp6kgacgSLubImOIu6odUgHHRthy9EAeyjzGR5+i9H7lrZJFWVyYMM1J9yG8lk4tFJ6PB4StymGP4pG+sCMmSlhi5khymIfGmwyljwUu/wBAbyl89aa3FReSU87lZ+sq3wOjXNrXlP70mAsg0LBFpKW5hCf2ARK251594EZiH8i72RObpHblzpopVrFgr3j2vouphah9Ve+m9CG29UVPqKsPFAQoHUMdpsVdM2c8o40ZWEXROsTmtFTXzww1sF5KcEBN6BqaHaBLu1fq/+BHVrIrPOHN9WbQu5Rb8JepH6ix8ssHPo9GU5a2ceoDjYU9MozuLmaazo8vL5WVOdgq2zApmwaxsHVs5clcLarxEaNClvfi5qJwJezARw== X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV2PR12MB5869.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(4636009)(396003)(366004)(136003)(39860400002)(376002)(346002)(451199015)(36756003)(86362001)(66556008)(2906002)(4744005)(5660300002)(7406005)(7416002)(26005)(6512007)(186003)(38100700002)(2616005)(6506007)(8676002)(4326008)(41300700001)(66946007)(316002)(66476007)(8936002)(6486002)(6916009)(54906003)(478600001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?MLVJUChSSpscljNR7Es0GWc95wuv7GrY/hqURGSVVHuH0S8aZC/GkhJQg+Xm?= =?us-ascii?Q?hjbqB5b8tDjOf779I6IHR8dKgeViy2n/WHFk6lvTAVoCBYe/DPiXaNGNKApa?= =?us-ascii?Q?9HE8tD3OgpPazKXwT8B+zcZW64N1k26Pjv6cdnXSUYx2QKanwdlpG44Cvmi6?= =?us-ascii?Q?ZH+mxL3sxRiz5OwRHKI8XOYX3bhIpdZWqrI8e0fSDs5zIwOPSmjuwhDXwIJy?= =?us-ascii?Q?FF8oJOxpxtjgBoN0Rc1JNh4/hIsPfGFQ/9Qvg5ZjzVmIlYajVWq5DlE4kfiD?= =?us-ascii?Q?7R176LPKsZUp/YsfxcYewJ1cxu4IQbBgmy0p6uOU0BZkFEAm5fv1SNuTmydD?= =?us-ascii?Q?Rr5YQ2kvDDrOq9+FEjhmn2RfZJaKJdz5ns4TGTuCfrNeBdFf7c97gnVsPSKP?= =?us-ascii?Q?Cgk9XLP6DMy5nOCjMxdkXsCoA0l63nH/+2dCPFc64f4AHxnuK5vHRGswKGPA?= =?us-ascii?Q?iR7RIcvNyoJJ9g3ClewrPyleh1t7hcK6nWLGkz9J3jnBiS8aM/uWOm7spfml?= =?us-ascii?Q?xc7LcKq+Esw1THxBJLnWRmPUMbsY18+htBDio8mvDqW0GvtHiJIEK2B56FBr?= =?us-ascii?Q?iUDXeIjaWd6Od7gwqTefWhcGmpZ+8DTnqRuxYgtZ6ciVbFDCdvayzuu3Tm9w?= =?us-ascii?Q?Y9jmp5TueJwYS+QwJA/9lcIr92Sz0FY3xfm0D6BHI5ncQ+jL5L2m/w/+AsBp?= =?us-ascii?Q?1dIbZueL3bCz9wDpSqvMNhdZkQlsWOVW3NwoGUAyvGf+SH8z5XWfry/DgQsr?= =?us-ascii?Q?HEI26wjsd0fDULeQGFe4f5ub+jNaXokxIN4fiT6nAMwsbpoPKIZrWTyd2eff?= =?us-ascii?Q?O/tcza/E47YCRPBYEfdg1cRSb3w+GLQdexBlmL0swjukUZ5AgF6Y3QA3/OzT?= =?us-ascii?Q?cOYGbrCaPsZQDmacQV95mxiHN60KBFSkvjM0Qll9mc4sE2gTtr3fgOdKW4QG?= =?us-ascii?Q?lNY/E6jomNwv2DJ+lF7oyfPrjoumtFfNeB25BwhD5MNxDtmKgc8ge1zMiRxK?= =?us-ascii?Q?TdZzKCDItIQRoKSiUeJju3JCudDeGqjWh1HrzuVeSrOIMcrWKW1Zh31d+WIV?= =?us-ascii?Q?3p0lpiKRdTiIBj4YW9WLNkGexpwFAFkjNh72NhBYFMQPVhEHlWDMSR/MZWlF?= =?us-ascii?Q?ziqoT+u9DSIeUMGyB6A3q13PQ7FkAUB4JX318KiiMAKKrG+YFLnr/ihy6Z23?= =?us-ascii?Q?cTRTgXZY4hNshdjFoeVcdPy0aFzZhW3F07HQCQduyeOpE7tgfBMLywOE7Wjr?= =?us-ascii?Q?HTTOFwkdi5MbGJH61KFhbvuKFQFvisDPHGZGJUMVqSmtXyCMlo2Tio7DN0fL?= =?us-ascii?Q?/UCRI3YeOAh1NHC8HSaeSGe9PMLFg0PGIEx6CX5opx3IRyjv0caIPcAaNmDi?= =?us-ascii?Q?18msxovDUSZGjEOkIr+Ems09tTxjF3v9+f5Y2Ycot/erXXafcPcyXrG84C0d?= =?us-ascii?Q?QlMDX+/4B2J7M3jtjt/q4i0QEo9TPl6DchEAAcy41IBEfl9bouzlhunhICZQ?= =?us-ascii?Q?X/gI7LPkWMWEVX68D3HXiPUor4XHTgJ07uUwkBxAcZH+mAlGKcbx8EUPiy1A?= =?us-ascii?Q?aJTCxK1R+SfmaWtdHOM=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: c9d22f7c-3c70-47a9-18ee-08dac11d837e X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Nov 2022 00:09:33.2200 (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: yIIZ0ign50Is9PpXNIjtX8S2Fz739ASBA1qFKeKMxiLI6tY1uBgyjTGOA/U/DVUA X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PR12MB7774 On Mon, Nov 07, 2022 at 11:53:24PM +0000, Tian, Kevin wrote: > > Other than that, userspace can change the IOAS it wants freely, there > > is no harm to the kernel and it may even be useful. > > it allows devices SET_CONTAINER to an same iommufd attached to different > IOAS's if IOAS_SET comes in the middle. Is it desired? Sure, if userspace does crazy things then userspace gets to keep all the pieces - it doesn't harm the kernel. The IOAS is bound during get_device, and that is one of the key conceptual things we changed with iommufd. Jason