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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?TqxMH6n+Uz6DHoQTOoxfQk6bDDxkLV1G6uvtN+OG0FJfYxM1YHiZCVtsOwU4?= =?us-ascii?Q?XmSfcstbWPjOpMx6yImgAcRS/iwirWEsGhLUenb5s42JlVcp75dJ/JMOaX/M?= =?us-ascii?Q?QXLjuNpYtfI8W6HANghEndf2BOZavYbYcCIUcKxXdTrHLoJ6raSpeeE/yNgj?= =?us-ascii?Q?F7qTscnNp2MpoGvY+PYZ9JAml98dwjj29Vygn3frqHkPnQCug+e+qQqr46cS?= =?us-ascii?Q?JQGEAy27vhTfvrFbrgofxhQY0mgvPnY+MdSGw/grBtkRib8AlSCo49LvwZHt?= =?us-ascii?Q?xvKv7SU1crSAnOQLC5he9JAP9Kkq+i0kF/Kw8a1GjbuE8d+oJjWuPQoP9lFF?= =?us-ascii?Q?2mepulUnjK8PTAqQbn3ccVjRe+y2tMd4abax+18ta7jP0BPeN7IytjYf4M+p?= =?us-ascii?Q?FXLs67agaaV+D0hTpDABx/VSOyZeIXUAKkkhoXL6YE5nhhLhm/X0YB9ICwCx?= =?us-ascii?Q?yE5+49N/Bf7QwZX4I4UxvXGxKqSVh2Jkls6Pp7JOI5C9uZqhFcXDH2iMdZas?= =?us-ascii?Q?aTL2gfqR2bO6GH4HqFpN4FdsHBINlZ4cGM1IFjXgp+K6AmlIHsGw896MllRJ?= =?us-ascii?Q?0V0giDcSV1m1/YexGHPUeDXnl0U27kIbclKr7CmF/ZcPIzMR6r8ndneaY1//?= =?us-ascii?Q?Fmk6D35oir0iEHMwOgkSCgYpKoMNYmPNxOdxbWxO1R8Xxk1pQxByJvVuIZdl?= =?us-ascii?Q?4oba7IsQ2F6wVVjOk0mhGq4+ArI0TMj33pZrOklYSnMoyUMldZ8bzoCS6ffr?= =?us-ascii?Q?HVDIydxoyUPPrAI1Zvnd+kmfaDz/gjNt0k9dh3lPIGZy5OqKAca1DdGJTvlb?= =?us-ascii?Q?zMN8o1cxjYf4P1RPp01SWxyJr2kcRjpwjXco1bVexEcME9uc9/LWrVQJTbLC?= =?us-ascii?Q?p0dFF00LQ42jeB3lJISs2GWTSHFz4cu+uSjuPaV4PymstRrVpexb5A+6A8aE?= =?us-ascii?Q?NF7pKvnl4V9yRnRJZ0tL5b7eLE68vnaAAfGvcGnMnmkpfqVPhcCLXLDssZ8M?= =?us-ascii?Q?NFqnPmJ7EJCIoYsHwLSQkCCBWbOyB0DfI5D3Fz4N9OhJlrlKo4IZgWiExMMm?= =?us-ascii?Q?Q/s7lVyVq3NGYWkWWzNGPvoCkzDCUUHSHm2IE2gosXfXJwUsfV7yyNhPRKne?= =?us-ascii?Q?UXo8Sj6bF1t3+xDbc7C8wlYllCNGHBIigRtfqbmdjRnnxiuVp+qiGfc8M2sr?= =?us-ascii?Q?M7qSOrMn45ioDlSnYm+X4cH8ATq+vqvd6FRNEloOjfMnByYuDMx5ua2+rqAa?= =?us-ascii?Q?Nz0jtcpsR0+wu5AygrDADIzClrl7Z3QMNMquWxdvbWrqm8e3O5Gk+vraH+L9?= =?us-ascii?Q?YKygxlb13conmEvAXrXvY31J?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 22787174-f942-44c2-a9dd-08d99254e6c1 X-MS-Exchange-CrossTenant-AuthSource: BL0PR12MB5506.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Oct 2021 16:32:39.8514 (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: AO5IyDUDMAt2GkyZCNVlv7xvSOPKhRmbrkrX3ioCknIA4n661umvtjne0vUerUbH X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL1PR12MB5189 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 18, 2021 at 02:57:12PM +1100, David Gibson wrote: > The first user might read this. Subsequent users are likely to just > copy paste examples from earlier things without fully understanding > them. In general documenting restrictions somewhere is never as > effective as making those restrictions part of the interface signature > itself. I'd think this argument would hold more water if you could point to someplace in existing userspace that cares about the VFIO grouping. >From what I see the applications do what the admin tells them to do - and if the admin says to use a certain VFIO device then that is excatly what they do. I don't know of any applications that ask the admin to tell them group information. What I see is aligning what the kernel provides to the APIs the applications have already built. Jason