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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?aAf6TJ3J4R4p6depYDYe7tv/p8djOkZdRAzgcSKNfawZNxjDsSfgV92Jd+NB?= =?us-ascii?Q?gvXLxXsKZYePohO8m8SHhrQNjMPJ/VChHglXy986QtyA5CelVI6qb8NZ/qu0?= =?us-ascii?Q?28kDKa3SB85noIFaBssqxkKAxGeknXK1r0D5ZwUm0VPrf8bmeIXYX8UXskaf?= =?us-ascii?Q?9tpYhIK3WOYehioL8BB+rWN36Z8WJKNVsfeSTqoFMSujlNmfB+Uf98My1qNP?= =?us-ascii?Q?GokgcNcug92NVmFB7coY+qBCmqd2PLCkCyKRhvxyWu2UpiN2vlvhNrZLAENg?= =?us-ascii?Q?T0JXriD9stvQ9tZrA5xkoo4Ziaio+5Ccmuxt6PvJSLXqq+FqMqsBUaXz7bmL?= =?us-ascii?Q?p/oc4YHhmMNDdRN5hbHkQG4Qr1jEic/B0o4OLLzXFeEm2GFWW/B+uHkOfPfo?= =?us-ascii?Q?dglAkuPGYuQpdFp1B8ZIO07a+B74rbJsrZfmQxpjtLaqTAm+/VBaVSsvLcCr?= =?us-ascii?Q?qnhhU/oPefpiGJtH3t049bi3o7EPxPvE0MF4FX/jWdw1FinSYsTGJFgYuNYo?= =?us-ascii?Q?EdW/5xw19q+Yy06HVPoIDh28u1hx4VEqYZEuqmlA/uJQMRYuckp6BY89c7Bj?= =?us-ascii?Q?lxphX/soTDH1tSKB7a7Nz3kdhPQTzPK/Zp4lz5zzrKgeD4Aqc48bVgQ00Qw1?= =?us-ascii?Q?1WSSpMLqHGFctjtD61G8/J4zq+oaSiFLOgHKDXHwL0OP9TKyMDOpJTa4DEsO?= =?us-ascii?Q?b6QZKTcy6Bg6PkGPpcykOO78xdLMiQ0ZjF25/iOdMjeulGsKYx2ebUfFIPsQ?= =?us-ascii?Q?Phd8ArkIjhJP4OGTN/xk3h5Wc2/znXUPnXmVCHhbYdovkKIOO6OClSNsbUA+?= =?us-ascii?Q?8WLW2fIdJiEGy+GmyehKlwBmawPO+3YbnT41hYGfZjhRfLFTmdS8oQpBe2eH?= =?us-ascii?Q?MCFG9sg76V4DQvLqbm8XoiGseUVd2Qyf/p0p2gnba/IP5aPS+MGiZs4zdYWf?= =?us-ascii?Q?7FJJqkdiPk0cZbLozlpFeqjUKlaXrMjnnYgvFbBARXOptV1vbaYNvakmXCfQ?= =?us-ascii?Q?teaGfQ4Z0GbnqBZY3NUXX5MZYBtlDj2OgXK4n2XZY4XYrXMv4HNtkTz9nHhE?= =?us-ascii?Q?H5NXJwdXVSX2VlIGhfTE6Vgphbo5qnYTqp8PpmbOca+R6w+iZx8nF7DzuOkH?= =?us-ascii?Q?aIQ7bjdNgVtylqMcMJsmwUG/o7/Bvb0svXNs4rnL+9E/6KexR/BIRV+SlVox?= =?us-ascii?Q?D6JuWMPXn5UrBHkm8KSgLgmHXLsyyWafCVktUumWAMpDcPR439orwxmvxGy8?= =?us-ascii?Q?jEH0SW7nvoK6Orcuid53tXaTLg7F3rUFfkRam4Im2ba545ZsovNWC/5Ww+rD?= =?us-ascii?Q?cvz+pcxyzDfMfAJAKS0oznZSKoAml0xGV2vZzkCDmnj70orPtLp8Ftc6k91d?= =?us-ascii?Q?rEZ6qniWDq7eJWPVDJOoTQtizGpAUDjkLAuy+4QAKUUk+Yur806/YVsJzaTc?= =?us-ascii?Q?YZrmnH9n+g+fw9k2lnMmrLxnUtRV3PYDgPfv2ouHI2kp859XlBh8YIlOv4LS?= =?us-ascii?Q?mlQilzDhZ5Ptl0cN8Pq8rPimV7TJQQgx8Ct7vK0JzK1whpbvUyCU2N/1SfeA?= =?us-ascii?Q?Nee+LngJ1a2J+66z+ccLbAbDsjfHwTHpblhQfuZKhbypFoxCv6hDGKGG1eqO?= =?us-ascii?Q?G6zC6dHCG9ih2+UbePJeCT+UtkrvurDnM+bdyZwge3FroQy0Pc7kmy3wPvvT?= =?us-ascii?Q?kJ5UlHp7oyOdnZeAw+84P9rJxxyB7HV1P9mT5/dTVmSfmoNl?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9d2a57f4-e853-4a5d-ef2a-08dee1a181ee X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Jul 2026 12:14:52.0960 (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: WFkQXigpzk1xQguB7b1HoDLfLOO4mzdCXIrXlaEnSjZPc0HJ8F8uEvzt0YPxh+ri X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB8083 On Tue, Jul 14, 2026 at 09:35:25AM +0000, Pranjal Shrivastava wrote: > > + u8 ttl = FIELD_GET(CMDQ_TLBI_1_TTL, cmd->cmd.data[1]); > > + u8 tg = FIELD_GET(CMDQ_TLBI_1_TG, cmd->cmd.data[1]); > > + > > + /* NUM, SCALE and TTL are RES0 when TG == 0 */ > > + if (!tg) > > + return (range || ttl) ? -EIO : 0; > > + /* TTL == 0b01 with a 16KB TG requires SMMU_IDR5.DS */ > > + if (tg == 2 && ttl == 1 && !(smmu->features & ARM_SMMU_FEAT_DS)) > > I agree we must check this but I'm a little confused, How is a user / > VMM depending on the IDR5.DS bit today? The IDR5 is exposed to the user > via hw_info AND in the uAPI documentation block we explicitly mention > for struct iommu_hw_info_arm_smmuv3 the following valid fields for IDR5: > > idr[5]: VAX, GRAN64K, GRAN16K, GRAN4K Probably soon we will add DS to that comment and it will be fully backwards compatible so a new VMM following the new guidance can just read DS. Thus we can't have any kernel release that doesn't work with a VMM following DS... Jason