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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?nqKU4jD0hfDZGkh/Ox2r2i1942+79kTMw2flyx76XPorfVsTMTbbMM+igR3E?= =?us-ascii?Q?u0hDAs+ASsWKcS8ifyWeEWYhfeiIgzlupvNvi1iRjqmoi9KoIg20MJafdgVD?= =?us-ascii?Q?oIbx0IO9HCDfaVwsRRl2aPn5l6CpMblyX3hjuG/52CV1tgEiChqTDa87UF75?= =?us-ascii?Q?kho3qB57YPnrOUp110GeOZjXB+kd0RAXtKH3S6f1Z2LQOwZyS8/7et8yFBJW?= =?us-ascii?Q?/h9Q2RbtuAPaJPGgT02xLwd0ng4YDJnX994/G3dH4V6arxzMl+FIo6UDpyF/?= =?us-ascii?Q?Wmx0KlTDN00kl37G7asGWltoKXPo9BK+3qnYepWIyHpYsg80mCyRUgc29lYi?= =?us-ascii?Q?9dch615JwZw9TgQNqjccLf8ER85Ve2vaSo2+uhqyWJTw1OwgPghTDQJatJJm?= =?us-ascii?Q?jkOfgu8Y2AF42OUD6YEEqc5EzsVxORM/mGIgP/HeJD28qR8c4ZqeWVm/6lYE?= =?us-ascii?Q?OwevKZ9NEtBrZjpa7TjZtg+f5baEMIxtmJIa+7uw9Y+PKx/cYXs750gXGZv7?= =?us-ascii?Q?zletdu8AyU4fijuGsrNG2cmkm4lXdF4Zv0Evg73a8M3PucAeQ1UixFPt1C+s?= =?us-ascii?Q?JWlTO/tUV8efuXWIf9E5Q6YGOur6No2thpBCWMmnfPruHHVP0UREmgNqL4jd?= =?us-ascii?Q?38gonWSYBX7WXAMlplVPNyrgoRYf9Dkq+4hpPbcsQz/tARQcyNGcaFxNjwp7?= =?us-ascii?Q?Esz9Wte/oNZDMqeLqloyrEKm8Au+I7NovsLGg9mEnccDVe3ol8gKg1ltN/rs?= =?us-ascii?Q?P8Cte0rcmGnKZ8IhuO4onHiiElUo1askLcf+k9rVHfHCpB9d3FOS5bfV8K/8?= =?us-ascii?Q?kuht1I9fL+dLMVC6WuYaH74R8fNNuI4tzUj8yozLOdrwVjMbA0n8kQBuhbKj?= =?us-ascii?Q?xHTF8m1KxJpArohDO4TVRL3miKMV6BC0I73Y61Lag+jLpGTXwEm9WST/CvCc?= =?us-ascii?Q?WCf6nIz81pWveofZrS66jJI/K3r6Wjg45YX9EufpP2zFIspYY0+qVvZQwp39?= =?us-ascii?Q?DZJh25BPBPvGDtjD2xQ/X/+XQnacdVxQclwqoRYI6dZ+exjBso+ffoHi45zr?= =?us-ascii?Q?vdLQB4KJrCCKDietYChq+06JyOzcv4CjjAIym9NEN9Ics5/RN8on+/XMA7il?= =?us-ascii?Q?ffDBkLI/Rt2Mn/bSN9LmP00qwTKkyAiDYAvYtLVd+VEpMg0yDwA9a93VWfWl?= =?us-ascii?Q?oIqflIqhj+ANFH3hAaQeSMxK9YWxfuLz0hLul5JCKzad4gERlPOAzki0R6pU?= =?us-ascii?Q?WkYaaT6lBCcty0+C1epBa93+D64K7SdEm5ins5Soutrh4Pxi+c128N8XEQgQ?= =?us-ascii?Q?4+mNzg+/Had0C6Qqn1Mcv1fnMq9IyzplTvDXETxt/116+9XMACuHr+QYmlYw?= =?us-ascii?Q?yS1y6UHO2/Q40rJzZENyD9MNH5z9PA6qhrPrmuaaz130wbEVBsLv34ook8jo?= =?us-ascii?Q?ZPAJEz7rd3S86Z9PRWTNG2hWkKNOLKxK?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4d907588-7964-4a13-91b6-08da07a9aa72 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB4192.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Mar 2022 00:04:11.7628 (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: bmZmPOIHW8yQbtW+jsLGD6VyE9ZY38CI3RErsxyc8Rj4HolJb/+hSKraq/tkZmhu X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL0PR12MB4866 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 16, 2022 at 10:23:26PM +0000, Luck, Tony wrote: > Kernel users (ring0) can supply any PASID when they use > the ENQCMDS instruction. Is that what you mean when you > say "real applications"? I'm not talking about ENQCMD at all I'm saying I don't see much utility to have two PASIDs assigned to the same device that perform the same IOVA translation. So I would expect the list of attachments in an iommu_domain to have exactly one device in it and multiple PASIDs to the same device from the same iommu_domain is a oddball corner case we don't need to optimize for, beyond being able to allow it to happen. Jason