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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?UEOevReBZfLpSCh4SMX8emeF9IVIS8XvzSmWIPGqLP63s9r9lrfj+w9TxjOS?= =?us-ascii?Q?vHNjpCySeSUMUpvU72CxnLaJIgK9aWsWkgr+a4ZY7qSqTVMJOyfcGfXUKead?= =?us-ascii?Q?jdTChTBeH3oHYTSjsAJwAyehmp4wlIIB8J5Qyx01zpe7H5D8tiN/PG0F1b0b?= =?us-ascii?Q?eSb68RgTOrKd9/ADO6nOMcUjZh4BXyGpFsa2IIMWtV5rzYQjBOUjK6BJJvVL?= =?us-ascii?Q?46StGXePJ8GvKgaFxsSo427s+tZwqOGHsdlx2FYnNjl0HwQEwFKXxPaqBJd4?= =?us-ascii?Q?zzl26SaLHWlRrKTtiziNCuqVS4j2hsCZpc5fLz1emjtqnpwrKR7F/hjgOJo0?= =?us-ascii?Q?RinVqDVWaq0R09Z8P56gFiTvF1Ge6E0UMjQtnOwRAmNGBCE5HaKGogRQohD2?= =?us-ascii?Q?xwVflxCRGp+gFQs+XHDr37lPhSsHE1UUKxavJ3dh8a+N++3LJYCZACwejqk/?= =?us-ascii?Q?rm1C9IDsxpQ+ZnxwiJp66Aby+p3O8aDsRARdfEz8M/B7HDBBxXylakE4VOuV?= =?us-ascii?Q?1VUbPhl1zcgoxyXPMvL+csnJJiF8jsu5hzYIxRIKeHExK1IZjfEiPCh32x/h?= =?us-ascii?Q?SmFOmUr3MRObQcflKytfxEEq9tkIQo0bL1c+A+n2cKIEfnMBiK2qQYvfkgo5?= =?us-ascii?Q?djE9ngV6FSqvNPVe069pq5jOFH1fqHmxUvTypephHNb2bBaQoVSdwXdOCy/g?= =?us-ascii?Q?dbGOUMK9J2N3oRN+RKQDf5rG8Q95wiha+Wr1mNV+AuOQBvsft36Hk4L5BcSr?= =?us-ascii?Q?WeQM6eylwxrBXYllbql2SJXKuulCGlCZKDGlScMsB8Uj8hJlmv23vNx7WZgZ?= =?us-ascii?Q?NsEISYd+smL5pkSfxmpkbBXbQfcUVrMVCVkTyRiK35q6t664B2eppaLUYtfr?= =?us-ascii?Q?qoSHh/TVREWzjubNYmlsHufpsXs9yR0EqKUDjsIyrddAs7JzXhV0izrezRrJ?= =?us-ascii?Q?iM5iVrOmL5dczMY8Ax2m2sQEIkYwVsIz2ayShar/ZfHFJ26nNoLNdRfwP8vs?= =?us-ascii?Q?wcT4pjwuKvoRN3z/ijQNaAumSNH7GR9YzVxhXaoRt9wp9/7zHEA9NIX9KAoW?= =?us-ascii?Q?AD2iHwi72tt8yjDd1jB5DUWaG3VxmAcKtecQyDo4eCr/g6KeMI4F+leX3mss?= =?us-ascii?Q?5fhcHOduTDRJkJAqwsE9HFLVnnU0MbQXeQZqb0fsvzha10ZSkRpnTLlLGJdE?= =?us-ascii?Q?QHoPhGgb/pjXvehxVFEkWTfsFyg/kW6cxn60lX4oaRRWy+uZHhSF3EIZDDBa?= =?us-ascii?Q?bDD8gvMBzzaSq+POlJu1VdmL/saANGksLmxYLdTiN8bXNhYZNr6+PerKgLM/?= =?us-ascii?Q?1HG8wTccWhjBo1ZeXFgtxLKaC+hCTtGxAKXF0BWfbN6S315sY4vLO2CRNVRk?= =?us-ascii?Q?H2x0bSxytfqKNPhhjBUplf2BQc2ljEkl4Dh3RNcFidB7DGK06qgeTGz/wDvP?= =?us-ascii?Q?Kwhj8xtArnBSQNcTndwbxaH7eXl2aTHkJiJPOu1XH5cUnqSr+WlDfN8OE9TP?= =?us-ascii?Q?l/4vCcrhUFWHdDsxNG2X0atxtAjgFROhte6uCrIasVMJMrDYTashIyDQfWdr?= =?us-ascii?Q?vdGOA2vypo6ZNfPgj2yPAnN5L6ubBGq5IvGqigMU?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f644c443-dce9-47a2-4766-08ddaf62933b X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Jun 2025 18:53:27.0946 (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: /3EpBINhL50Zf/45X2odqituZ3ZIbaC5vaDsWp2F6KlMdzQErsWhLy2nPvz4ec83 X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN0PR12MB5762 On Thu, Jun 19, 2025 at 11:47:24AM +0000, Pranjal Shrivastava wrote: > I'm not sure if I get this right.. if the user (while porting a VMM or > something) mistakenly passes *type == IOMMU_HW_INFO_TYPE_INTEL_VTD here, > they'll get impl-specific info? It should call the impl hw_info which should fail? +static void *tegra241_cmdqv_hw_info(struct arm_smmu_device *smmu, u32 *length, + u32 *type) +{ + if (*type != IOMMU_HW_INFO_TYPE_TEGRA241_CMDQV) + return ERR_PTR(-EOPNOTSUPP); If impl ops is null/etc then it fails: + if (!impl_ops || !impl_ops->hw_info) + return ERR_PTR(-EOPNOTSUPP); Where does IOMMU_HW_INFO_TYPE_INTEL_VTD return something? > I agree in that case the impl-specific > driver needs to check the type, but shouldn't we simply return from here > itself if the type isn't arm-smmu-v3? Then how do you return IOMMU_HW_INFO_TYPE_TEGRA241_CMDQV? Jason