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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?p2PM3O2b0vmhq1P+kTBWp8dlBtHkOIUUjZ7pPeTgykil2TWqVEuJs5JkB86x?= =?us-ascii?Q?Y8sFhXsM++oyVfxy2Xo2CD8Wqlf4o/F5Ph9r+d1ooFCsD45gSyEFMUs9ppb7?= =?us-ascii?Q?QJ5KgvoQo7FsCwX4snZDlhhfw5HcE5b0+CZHEPf1YJDcfQBYE8WxVUceFU5b?= =?us-ascii?Q?wy/pd7GkEFzNb4tcfy7Io0SuwdcZ5aBPV4ff6Y4ijRkD8OAsYI1BpS8Cdkq8?= =?us-ascii?Q?EifpOCOUJ5WSIaNLzYaWeq5qhLBpB+yOg4kpOjdFAwpAVBi+dXu0JYpDvXkl?= =?us-ascii?Q?+XHFBMSMrybht1e0DrR0Lr6PeycZ6bcHjv68GT1CmUS+NPfwD2NvsKsa84ZD?= =?us-ascii?Q?mklLrnw+yTOu503eezqHgQwlVbgjt9qVv4diw7GyY3FV/Em7IjiDGTwRAHF1?= =?us-ascii?Q?1u1IOSPkUcclsNAhvvE/MwX/fpN0UDYGMBQZ0Nvogk3rVbd7bxQlGR2YEa6K?= =?us-ascii?Q?E26BG3WDSQasAnChS68g3dqCev9gsE/D6JBWmtB5clbmwZ1heD3EejODGykt?= =?us-ascii?Q?DpieRnAo7X3j2J7b4u5FwSxqA1hP9qlIlXdUqbXQXAnv8sKRtmMdh58sX6/s?= =?us-ascii?Q?YFi1aSPFlqalssGxlpC+Dg/4v9qUTNPXGAhGUK+qOj0ktSf9g9V/ZQ8TA5gY?= =?us-ascii?Q?ASHpnDSAW+Cmxe1dAuUzZ6pq+bAN0FkMfaxWqRHnGY3G44KfAWA4baHlHnAq?= =?us-ascii?Q?xxQ1cOz1BvjJ+Z/16jwcoB39PlQTw1ac/JHgkraURcB1+QM8uwlW/DtjfFn7?= =?us-ascii?Q?1R9UD5ZWJmj14MIc9DWiM9DJYccrMuC86qjo/vGUkYCoZXyIYR8aqPW9HXHb?= =?us-ascii?Q?eU7ZWK+xFg9ayLyg6lPbM5W6eJhY5vl25s4JHDsB5lFJoBtp4LyZCTE66xrZ?= =?us-ascii?Q?4bYiPGt6o9hYN+I0jMoQMsCRgLWYZbzwa1YUnAKntxGlEyfNz3ieXAujuhi6?= =?us-ascii?Q?UmaIVxIwRLfVk9KrN60jb0I2UlgIXRyaRGmHR5/6o2phq4FehOr2EmksccBZ?= =?us-ascii?Q?w2dgu8e26PukIfHhaXY/5BBhhGErHyUiorPlUZ+TujLsO9MxSsG+9aMq9KXs?= =?us-ascii?Q?w01eoxHyBwN14+j4VhD/bjfc7yXKj2+0qVj20JUAHP1s3BJj3SLD0fiQobyD?= =?us-ascii?Q?+pMNAnvnGFb1t0iAsl3VU3H7H/cfRKet5jY6gdQXoVyGJxtJU+eEs2a3HXEI?= =?us-ascii?Q?r7EcV/+TycbJ5JlaWpd1TvRsdSUsKBXoJCxHgZAu2YtK7wE7UboSQTwMGrEM?= =?us-ascii?Q?XC9BPvGKAEWNVv5aUlsAfRvQ3DzWtp+t9rEI9gU1bNn/XCLjik6soORbxGHO?= =?us-ascii?Q?MOXDaguYjlF2Iur9l0s3YGMTCdhMS2BALArcSVJjsRzO1Qz014sIvQyUoFH5?= =?us-ascii?Q?fREyEYqYVpKoqqt4GG5/F68+z16JFuVaY61RI7x/AEeTyjkb8rqJ1EJBzXQ2?= =?us-ascii?Q?mafKaV7nc36Ar3UkJAvCZIe/U/TCln9YVFYb5uE+9XceFeos1g8AEZRmIGR+?= =?us-ascii?Q?Ueuq6i293UBRejszQVtC/w1fayTk3h2WFszPbjD37b8eIOAMDw8wQw+/RFix?= =?us-ascii?Q?JWQ4HWKETa5A+6ehq9/LIfEGLJSq54w6tpwR2PQp?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 869aa8e3-80d2-4a2f-3013-08db1f08c8be X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Mar 2023 12:37:59.2883 (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: CenDDLScrVULRs7ScwYsvsYJ/zjVTpRnH6X3QhhSuLQwScDlw2NMbmB0yVFtBtJk X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB4413 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Mar 07, 2023 at 06:38:59AM +0000, Tian, Kevin wrote: > > From: Liu, Yi L > > Sent: Friday, March 3, 2023 2:58 PM > > > > > What should we return here anyhow if an access was created? > > > > iommufd_access->obj.id. should be fine. Is it? > > Thinking more I'm not sure whether it's a good idea to fill the > dev_id field with an access object id and then later confuse > the user to get an -ENOENT error when trying to allocate a > hwpt with an access object id. > > How can user differentiate it from the real error case where > invalid iommufd object is used? > > It sounds clearer to return dev_id only when there is a true > device object being created by the bind_iommufd cmd. Then > the user can use it to decide whether to further attempt > dev_id related cmds. It means we can never return an access_id I don't think this is a problem, the first thing userspace should do is a get info to the dev_id which is needed to learn which iommu driver is running it, if that returns EOPNOTSUPP then it isn't a physical iommu device. Jason