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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ft3tZbVeUv7DeG+U/Bld6XHW/+qG1Sfo3EguZpTubmZCC6zgFa2XEu510Bg+?= =?us-ascii?Q?J80/WO+3buclJKLWvTnHl50xZcrXM1yxYNS6LeU5ndafqHFqJF2a4qEbHqdF?= =?us-ascii?Q?zxfNxUPKXHl5bkIks1icXHm0ltMRlpBNNvpU3gDYIl9R5JV+Xxn6lcyoFUtS?= =?us-ascii?Q?lqqjsfji0KNXLS+YXtXOA5wXShHMhvPzvUn6ybmX/lli4+XYF/mBxNRFZTtG?= =?us-ascii?Q?pb/EEq5BRE3ADZtM9jIFcqHMt0yLC2M70hweH+V3TcqbpTY8DKJa0s5d4+l7?= =?us-ascii?Q?gV3DaSMUbtVGAl2sfy0iA5wb87XaaihjYH2id28+F+f1KnobeYwxF0fQ5fJJ?= =?us-ascii?Q?y5b3/P/DvScAlhzcSB//Ij6qu9jWL6eUNM+P7U7on53z0qZBWBLa+yxjn346?= =?us-ascii?Q?PY9yADEBmbil17WHiujXF7hcNNO9iSKvqRQS1+hcpzXg4736XgSY9Kz+NMhs?= =?us-ascii?Q?vYfCSxaOHfbfuPZrkKgTmYHOs5el30FVkrfEIsbMOW0obusEv9pKINbNxbRf?= =?us-ascii?Q?KiBgdlKFPuQIcDkFvS3EOJlxhsUPul6LDyavObXRBz3srqKZJK2hT6nPcL5S?= =?us-ascii?Q?SRFhla6zeHmZg8AZCKWd8FRpR0Rr0PX8sQWybQq0u0DPstHHLB+C8uWYmyIC?= =?us-ascii?Q?Sv92QjP/jSBUMwPDMc+q6bT6yDQiKJfYqJYNFYyNNun+RmfUtQ+KZ2o/+JLt?= =?us-ascii?Q?3T6CWUC8O+WlcG7AwoV4J72y1oP+CdkPrdX8KebzKCYDKs8pod7oa+LebCfl?= =?us-ascii?Q?xPr6F+YUtt1T+YI3elmjE/AZrbcHnw7Mz+Ni+OlPn280kj3m6Qvcu6Wy0gLu?= =?us-ascii?Q?0FUA1boM2IOEVdndwI8syydYtyg1Fw8FOcMxVGuLoPq/L4WCrTJw1jeAu+5a?= =?us-ascii?Q?hYjN75Z0h3XF8tamS88yLphxYiMqiKQXWS7cHXnAf3zCWRFkVGsdb8AFujFs?= =?us-ascii?Q?ZXXhY3e3QLDxRHp1JdqHKqXlOPICvrinmIZvH1d7aAFYpUk0G7gy5cBTh4e8?= =?us-ascii?Q?uHU9oQD26OttYhhERyzK+M642oX3ZSf4Sj1moZXrPaZocHplne6k7v4venkB?= =?us-ascii?Q?TtTcd9ksDnrf/uNs9f6Q9z/IGwnYlz6uV4L6t7ue+h5Y/CJoQKFfuoLxR5WW?= =?us-ascii?Q?I/0IFbC+K83rv+a63e6qXBGDN1PuP3rU07U5IChmYq8pGXHZxdlVx0YQZeEM?= =?us-ascii?Q?RKGdFbhpxCwDAgv/YdDjyGraZnmiZTN8SiwUOfxWiNPrx/0UsgDznQKuXtWR?= =?us-ascii?Q?rn2JzNhSRp0ugGH99vkHc9cxZqliPcrpzt5DvX/7FH8xszc6JideIJBoaQvN?= =?us-ascii?Q?jjhbL2+CefvcVTo/4e4dkQwEKomvM9hvTmnSOHoieH7kPpeiV6HOGQ6u5yj/?= =?us-ascii?Q?HHLKK1ok5TMlWCNCXuSstKHa7jSJm+hOP/1YpcxCa1VMUvPah+w6pY5dIhrK?= =?us-ascii?Q?asCELBqh56LfBYL8fPxCPX4fUo1T42ObK14+JCTvppyao9qw2oalAEM0bJt2?= =?us-ascii?Q?pj7yV0HljmYGVsSkJ+9e0Uu1uCkIArAYAIsBWupFpi6E/xoWkQZKxBXIxnWz?= =?us-ascii?Q?slhXdUKatuBa+BUXcGU=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: b0e18010-5793-46a0-3d23-08d9f6fae50b X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Feb 2022 18:32:49.6330 (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: 4NWNQNytKqbcqGBlHowJ7lbhp63ub/Oltj4y6XSzD7s1OsBavFPbeLUwoRVk6xQU X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR12MB1479 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Wed, Feb 23, 2022 at 06:20:36PM +0000, Robin Murphy wrote: > On 2022-02-23 18:02, Jason Gunthorpe via iommu wrote: > > On Wed, Feb 23, 2022 at 06:00:06PM +0000, Robin Murphy wrote: > > > > > ...and equivalently just set owner_cnt directly to 0 here. I don't see a > > > realistic use-case for any driver to claim the same group more than once, > > > and allowing it in the API just feels like opening up various potential > > > corners for things to get out of sync. > > > > I am Ok if we toss it out to get this merged, as there is no in-kernel > > user right now. > > > > Something will have to come back for iommufd, but we can look at what > > is best suited then. > > If iommufd plans to be too dumb to keep track of whether it already owns a > given group or not, I can't see it dealing with attaching that group to a > single domain no more than once, either ;) Indeed, this is why I'd like to use the device API :) Jason