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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: NS0w9vgqrwAUttU6ahyYlHcyRg8/5ixm3Cp/QFx5gwFnFur+F653vM4CEvkjfn9WYFcHFKcZXFan4rhiPyz2LcBJxE9l/33aYWRmfVxg8KzmqPCJ1h4N0Dx2dB8kyomluVKj5Ug4/sYjY+9L4idJztoPcnMl60sFX6WW0mQ6BLYCb5Wp7OkGuUg043OX91eYXTIAGzrdtyBvk7SeGhmVitxTplrW2HVxm/hAcC4sFspANwwS7rR5sePVjvh3FPbh/lqmHpSzJq06+fa09WI5fwJNMxCe04rF9F5Udf4cAD0Um/1j4aaKwBgmPoq2WjNOW9tClS7GbfBXY5anEP5I4lbNzRpUiOraMl/AGDAhpEbOJz30Z7b3pNRCSbsTfX+lJempx9jw7k5f05x+JNnxRKQmiN8FAFOf3cAQUy9+ITQp4U9xDAB3vWJngIXsnjLc X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Nov 2026 22:36:41.0633 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: f75d57d6-ff89-4f8d-b2be-08df41d6966f X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[216.228.117.160];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BN7PEPF000000A4.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB6303 X-OriginatorOrg: Nvidia.com On Thu, Nov 12, 2026 at 03:10:39PM +0000, Pranjal Shrivastava wrote: > @@ -556,7 +556,8 @@ static inline int __iommu_copy_struct_from_user_array( > * @data_type: The data type of the @kdst. Must match with @user_array->type > * > * Copy the entire user array. kdst must have room for kdst_entry_size * > - * user_array->entry_num bytes. Return 0 for success, otherwise -error. > + * user_array->entry_num bytes. An empty array copies nothing, though its > + * @data_type is still validated. Return 0 for success, otherwise -error. > */ > static inline int > iommu_copy_struct_from_full_user_array(void *kdst, size_t kdst_entry_size, > @@ -569,7 +570,7 @@ iommu_copy_struct_from_full_user_array(void *kdst, size_t kdst_entry_size, > if (user_array->type != data_type) > return -EINVAL; > if (!user_array->entry_num) > - return -EINVAL; > + return 0; TBH, this doesn't seem very necessary.. Though I don't have a problem so long as Jason is okay with it.. Yet, this alone would make things inconsistent: * The other caller in iommufd selftest isn't updated. * __iommu_copy_struct_from_user_array still rejects !entry_num, and its callers (intel and selftest) aren't updated either. Also, please don't omit "linux-kernel@vger.kernel.org" when sending a patch, as linux-iommu doesn't trigger Sashiko scan. Nicolin