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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?M54edRtbzveCbgQGAA/kRbvkB0VV48idd4Ik2LNWbDIkO7EYeJRoyS1CbBRY?= =?us-ascii?Q?u8gwziV0qj1ZmUQCJnpLeTRHiFTSMn0HOxZuNcuEorzzJwumyotraBnr94ut?= =?us-ascii?Q?Us2m+wqJ+i+6UdjU4nAMmpMX7BMO3VjtOsyYSEgH6q7+w+CxtXj1LzoehmKj?= =?us-ascii?Q?qxRMkdrxdOcmYLKdNeBHKO9+t0/YaomXVDlZGAmyeZHRRr7I9ouLcHRuZSTW?= =?us-ascii?Q?q2OVv9nfExibX9oEfcchIpb3aPRWgbJWnlJ4Jbs5dfbq7RxOAqQ3ruJGNHYi?= =?us-ascii?Q?U1rd51HtWV8z2+04XgcqpYytge3jORijG7zKU9bKxP7LYuJxQz5A8zIIyQAC?= =?us-ascii?Q?eLC8Yl2RkG64CJKUfadp59373p3SKzK75jbhIiaGfLCZvJ13Nc4QIpUWuCxS?= =?us-ascii?Q?mBR+BjA/gmZgGM6IX6aStvciUOGpo/sLV8hMsi36erMHIsws3WnHPgj+41zh?= =?us-ascii?Q?394/+kSZkigou6kwSyJtTITUKWQmt2WUmPPnyiH07fwKuHxGpRr70UC+6LG+?= =?us-ascii?Q?85GyH3tyD4yijjHt8jWeFiOL3BzPYsX//o2AczxMs8Z83qGXa8Yuz2S/sSJ6?= =?us-ascii?Q?XsUmOIDBZK/DNFxMSYT/suIMzpSIbKRdeND43zogNbvodft46iGj/HKZWxqq?= =?us-ascii?Q?+59JaFzbK4Gy3HI+00mwQPronQ5ExGkCluhw+Co+R1hJCBe4fkD8u4aFT+b6?= =?us-ascii?Q?8M4q3ZqsPvKm2C2UbmxqqS5uVdXoa+v3He2EYZSJ4KPNC8OsQhYWzxZHL1hy?= =?us-ascii?Q?pFL4CWTThRriJxrZZlJY+1l2gKRzlEOyDhF8+U+QHc7EP9sWEEyQUJIUcnUE?= =?us-ascii?Q?LV6v1+pjKGqS1AhyhY7p7VrVXzzMgCN4kxPFknvylpi5bW5ULNGbsLQIE5bP?= =?us-ascii?Q?6l9fgDjCk0CVvnwJXzQOkHqWjDye+u9P9e5Nd0mnq8Wb3PvaFa3IT2ACtiuM?= =?us-ascii?Q?YAa1BWZngC5RiikzjcsyuCoIe2OOWyKQ8mM/b3WDv+KXeBpNBy14OCQuR5jn?= =?us-ascii?Q?3eH0QO7I9u7TcNxRiEDpTDPHJubEdroP6WQW5Q39WRWYdykYWbYWswpe9z+n?= =?us-ascii?Q?CLEmMUzTxkVL7yV3L9ECVsn2MsVF8KQ7CrsXdbLuaTCqHX2KLgYhiqcxojzc?= =?us-ascii?Q?et98yfnwo0mEs0LiDyVm+Uzw8/qs7PAejH8FrPhb5mSHFeEH3oUX3zan/SyX?= =?us-ascii?Q?7ckkmzlu6L8Bl8ZvrCfUQkZ2EGCI3cwl5x/FTY5g2NS5zcaf976mcwA3eIc/?= =?us-ascii?Q?FZBdTryUhMt2YJiZMz/Str+y7sCJS2uYLxJU/G8qMfcooq694sNFaO7Ag9ev?= =?us-ascii?Q?1jpD8KNSqBYALLCNMLj9sQQgTlC7LSPuaqyOTjCF3QXS4zsxqGGi6sqdhGPq?= =?us-ascii?Q?62ghEWPqZ5GDeI6jWnna+yaPkYPdLQ+Ole0/Pa3EBfoS7MviSBbh+Xg2DhAg?= =?us-ascii?Q?6JMrI8tS0JLbVJMEvKSO5/P7+S1OagdaSXrMVdeiGKdKmEgCsAPWBYoGAcNP?= =?us-ascii?Q?2wtnUiqUH10scoo9PjC6JD30bRbg8WCT2fjxoyK1F3bOEfmNFxnjOi3Ry9Nt?= =?us-ascii?Q?ZBIB3NjNtZWByGulDEb0fGT2lbs8eundhqxY1jvm?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: a90a9593-d9ef-4cfd-004c-08dd6808aa7d X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Mar 2025 23:40:58.7145 (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: 2N9ZvX6BcFRdvrRBEAiuqfvmYSFEoPNR7pdRCMxf9p3CQ41C70wOBjmNmfqch07/ X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB6761 On Thu, Mar 20, 2025 at 01:02:54PM -0700, Nicolin Chen wrote: > On Thu, Mar 20, 2025 at 03:57:26PM -0300, Jason Gunthorpe wrote: > > On Thu, Mar 20, 2025 at 09:47:32AM -0700, Nicolin Chen wrote: > > > > > In that regard, honestly, I don't quite get this out_capabilities. > > > > Yeah, I think it is best thought of as place to put discoverability if > > people want discoverability. > > > > I have had a wait and see feeling in this area since I don't know what > > qemu or libvirt would actually use. > > Both ARM and Intel have max_pasid_log2 being reported somewhere > in their vendor data structures. So, unless user space really > wants that info immediately without involving the vendor IOMMU, > this max_pasid_log2 seems to be redundant. I don't expect that PASID support should require a userspace driver component, it should work generically. So generic userspace should have a generic way to get the pasid range. > Also, this patch polls two IOMMU caps out of pci_pasid_status() > that is a per device function. Is this okay? I think so, the hw_info is a per-device operation > Can it end up with two devices (one has PASID; the other doesn't) > behind the same IOMMU reporting two different sets of > out_capabilities, which were supposed to be the same since it the > same IOMMU HW? Yes it can report differences, but that is OK as the iommu is not required to be uniform across all devices? Did you mean something else? Jason