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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?6c1wsOgURruGlRbAqABLjXudnhnx/VkbEKC23kC8yhA+bA65xSMMDNMQ1xZ4?= =?us-ascii?Q?TRSPW8NUAhzv/42/WUojSTo8alFYi2EHMTkIXrAabZcbX86ZMstM2tmm38vm?= =?us-ascii?Q?khMpgZhYy3fitHBmlUaoOPbO4MoAyutsN6GvMDPwnIVeoPMx6RhZDHyzxSKN?= =?us-ascii?Q?fgAb6QzX5cgzM7jeu5osQxrW7hrr2z1teY3mIvveCSxVC01KU+eJwEgr/14t?= =?us-ascii?Q?53iaxnjxDWPCEIfpzx8z2APIHToLU548157dahCDE+IcVq4i+VPQ81BhJZoK?= =?us-ascii?Q?qyCwz8zEIRHdVVzXguP2u8aZg+HnvGWoIrCf01s4b0ULnPsmVB6TSsySoEOM?= =?us-ascii?Q?8QmNctiiyO57MQNHcoESDTrstEFeRi7ksFVmc9ZZ3SCRVJwFcqEkT/R7tSGz?= =?us-ascii?Q?josfF61RzO7HSDH8IpIY2kIO8bUkuTOt9xpz3TGWwoEOUrbv7My3q9i0Wila?= =?us-ascii?Q?Vfqfw0ii0wuxxZgTMvWmmO4xGL/rP7cl7FCmdpg+woqVfbCtYnA4pGUaeFyx?= =?us-ascii?Q?ITxIxpIQmMZUopuqAvrpLEc0btNp7E0l1dHTJOizXGHQBqjAypy9O5NdowAP?= =?us-ascii?Q?/YUuaWYSaKp09EqMwRYTqzK62kNeQgq+esL1Su7qlghVbfL7FCuBuU+d6VCF?= =?us-ascii?Q?8nEp/BHZN/PTRA68Ul23vOvniwIhme/ZFG7s5dkYgChwKYr2pOU1492KYyLi?= =?us-ascii?Q?1LAvjvI2lUzloIWFYgILqAe7l2flTwwdeBjp+t6Q3s94itLaoE7Imfa3m5VS?= =?us-ascii?Q?wisdq3lWzRBQTCEqTCTIDdM6P0G3pOn12+UDgFERRsdTXGQugvr4+ax91mCp?= =?us-ascii?Q?U82Lhpb+NgF+8BDOsk4GqUrvfivgk1mrd7DV4ah3sbv+kkRIKuyhDG68R9ow?= =?us-ascii?Q?w3mJniAIHe/PTHfOLmV9ip4/Z/ZPmfvNKSvPfvcSKiffyuJknsTWnowZRwv8?= =?us-ascii?Q?udMxFqXq/+Jw+TdnGKDV+RM0zcSBxBiDRiAUqb7GxSc27JVfj57PtZ6AZSkv?= =?us-ascii?Q?/BN6um5C67nXGHk/7/d/hMB/a0drHzSjo1zRBC/U1GE97CQ8v7F+IYP1wyUp?= =?us-ascii?Q?KRUbjcbwdp3tY6tqAEtWx0wOECndj6UP9cSr/jl6qTeTgTuo9nE4q3rnrMYl?= =?us-ascii?Q?bfzOWufAze6F2Sr1ZJF60qe6UPdpC1Ka6wIiWxkF75TX+M2PCp3daARUSbj4?= =?us-ascii?Q?MCEIx9InaB4Ja8uO0yfOYj+lp+PYoyxoe9tejKMAhQgkynfphI8o4dczVT1/?= =?us-ascii?Q?WBtQmS4/c67dxvkNDXAOboUe+z6gHVRVsV3Zs88pyxh0a7HS2YEgPfBnrjEM?= =?us-ascii?Q?sn3cg9/Fmhjp0yUa/TxTc0Bs0I2bICrztJFHQ0AHqQ7ePQI2lVJA6TK4m5B6?= =?us-ascii?Q?Epfptxo75sBcpD4HAcL1CgKhInJIXOGI/GV4hFZJohoHAvRo4OwtRD9kWUKD?= =?us-ascii?Q?W5ZCnBcGvgoRI7gb2bv+49pI5u5+lZQHrhQx8CUkXi0ovDq+NlWUczlNF1Dk?= =?us-ascii?Q?BN3nuPzBKq4rUjCZNZTc60eHQ10HVT8XD37NPJOFB/pgqYaei0193SG/vDNr?= =?us-ascii?Q?A7QVAWcsy5Ebt1CM8LCg9DpGHjcaMhU+rWHYdkz4sD/68O21mW9yC1wym94K?= =?us-ascii?Q?CvZSYWMKwQf27Kd0q7ionMprJ6Z73+bOGPCX0jj/+YmHdPI8Qa+54Ye7G7KN?= =?us-ascii?Q?7imZOr4U88s3/ymiCVcaLUk3foA/wlmeY1lBaNo7XQkZQB+OhoxWNyTPoziV?= =?us-ascii?Q?RtSEO6KY1g=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 7ef5c6e9-effd-4dd3-3c14-08df07e95a16 X-MS-Exchange-CrossTenant-AuthSource: MN0PR12MB5977.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 01 Sep 2026 05:24:53.1098 (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: wN+r0fleMfzbQroQs/yRBSYx7o6VaCbASp1xPNWUr2QGMYYABso8Kv26dRdOfhGtH3axXaihOfsZGUsc8/uOFg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LVUPR12MB999160 On 2026-09-01 at 14:53 +1000, Dave Airlie wrote... > On Fri, 28 Aug 2026 at 13:36, Alistair Popple wrote: > > > > Add an extensible info ioctl and use it to report basic GPU information. > > One of the first things userspace needs to know about a GPU is its > > architecture and implementation, so add that as the first field in the > > GPU info result. > > > > The ioctl selects an information type by ID and writes the result through > > a sized userspace buffer. The kernel truncates results to the supplied > > size, allowing information structures to grow and new logical information > > groups to be added without introducing new ioctls. > > > > > > This is a higher level for the future, I think we have two paths for > getparam type ioctl. > > Either we expose a big struct full of values with a add to the end > mentality or we keep a long list of value pairs, and userspace passes > in a list of value keys, and we return a list of the values. There's already been a fair bit of back and forth on this on this series and this is where we ended up - a bunch of info ioctls returning big structs full of values. I did wonder if io_uring could be used by user-space to efficiently pass a list of value keys as that's trivial enough to add to drm[1] but perf wise didn't achieve much over just calling lots of ioctls, at least when I tested with a mock key/value type interface. [1] - https://lists.freedesktop.org/archives/dri-devel/2025-September/524469.html > I'm trying to think ahead towards native virtio context support, and I > think having the sequence, > > open > get_all_infos > create vm/channel > > might have the most optimal ioctl count but also let power management > avoid booting the GPU on every open if we never create a vm/channel. Power management is a good point - thus far all the info is cached in nova-core anyway so there shouldn't be much impact there regardless of what interface we choose. Thanks. - Alistair