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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?jentSjukOMJtDkl8RkK5YMqSvkDGw981oOi/PpHNphryJJzVOOzszncv4kuD?= =?us-ascii?Q?J6Ko7mgkq/MNvzQ7BRvwt3SkLLasxmXDuh9pngKGmn+9oObDvFP4Zaj4U4B3?= =?us-ascii?Q?ToybcmoG8knMQwRWAmqUfmAgp/3WlWv0vabd0jQOS1ccgiVGyu1jxX8wEsgv?= =?us-ascii?Q?xerHyUvmTFFtiWhoFi5cXPOD0553CoxiDxdPC3XgGYOl9KUlNeN89DZf66ey?= =?us-ascii?Q?aQQmFH9JixuJHHDlpM5coVyz6o4TaS0NbIQ1ssELO65ErslgN+PFtdhNbhTv?= =?us-ascii?Q?obMI7uWHlcRZ+noWypmkogO71UIiRMgfrbI5fWbwqpPXEurgVbJMXYy6og38?= =?us-ascii?Q?ita1LyuG6PKg7guXgz1ln+eyeEwb/Sl2YOPUoOlaSM1WlH5QYkpWuxk4qhQb?= =?us-ascii?Q?/WLqQK7QzSABfmzncSK7DWy9XBVcckTJZyUg8Bd0pwbmytxMGA9RCmVfhMTd?= =?us-ascii?Q?Vs0tvGf5e+ek26xNjwoJZR8zsxgN+oeM4XqDYJZtsegW9dLS6KxrCqC+jJva?= =?us-ascii?Q?Myna6TO1RrBJw+uqIChFDhmEQ5d1EufKOHIc3hLckIlrIZl9yETGHAsfl+Fh?= =?us-ascii?Q?EUvp6dNsQQ46sJF9ltM2Le5vakuZXfpoLwHPYaHW53LD58V8u53mmadUZoqv?= =?us-ascii?Q?qcQ1dHL+TSSx+M//It6Ef2tzLoUQz44kaZt5qIGjsiv9mMDeQXJybAhNCl2K?= =?us-ascii?Q?4k/bnNAeSZNDjoSbRBJ1s7LuTiDT8/BYTimyrNuSPogVV0Ux3aSfNFQcsNPI?= =?us-ascii?Q?ZqIF+VydglKnx12qNHsVbwhvtxfaYhFomjUTvUtmZFXhlDBELwNCuabhb9XK?= =?us-ascii?Q?M+QdlO4zmQPinWIRytJP8rj/hYtF+EtdXHGbtY8AS7beAGvnNH3ndhvmy5Ri?= =?us-ascii?Q?JwkWDhrtyZ+8mVKw13lDabmH/vSQzYDFMSzxo8NBdrYHhBmtCwfC/u3ezplV?= =?us-ascii?Q?KLSxsOXKzBjX0KRLHtECzAwWuDiyCk41FFsfV+aKEFYFNBIw0AKd91+opVLq?= =?us-ascii?Q?9NoQc7ZzF/yasJ4O3sOQ7T8fc20bj+RwYiDkAPfzoq7B43We/J+FLZ/GanWL?= =?us-ascii?Q?TKRjGnDBgK8SKRsLANd0KBteFygc3CooDNaUdLrSqEhrK+ucDkN71tO50E/N?= =?us-ascii?Q?tBm9peXqOx3Ot9WapPtaAqHyixOqcwPeDp2SX4boXsQrQfnAvEJCGR9n9qjd?= =?us-ascii?Q?khVfEQtsMPGKKeAtYVYb0IA3XV2Zeh843JpyEAQY4KoK7mq+XmclJfXGbRM8?= =?us-ascii?Q?hW6dd1/yBVmjCdH92a7+Kg6Fpbb5Q2OuXCXTSuVS8TW5fgIp6Vo6L7CWyS7U?= =?us-ascii?Q?DQ7s1bKdYQ8LgcvRgEGtc2Hez+TRIX0ANmqrqzoEtsdC0q8lzxTyj8KX3g2H?= =?us-ascii?Q?AImmDkUQN4lENF53mTaTzR3AKRoIf/Cffy7opz3qbszoNQqFmBqpUW3VSuCj?= =?us-ascii?Q?HUVkuQy/G/B+/XCQf8fk54WVDzHFdMUOOiHl7iEoU0qdCNqPndamZNpUOatw?= =?us-ascii?Q?tmsh3lqzxSjfAcZ8+nl2SAnh2CebDrRw+pOknpvVyp3Pphv1EYRnfxlsRy1s?= =?us-ascii?Q?KrsIvr2/d8MVJLCW6Gz5U3zg1uZWxtwN6IV48OwVJdN2ZE3OMxduQJcS7n/S?= =?us-ascii?Q?3bvZsVciAWhxp3NmhTxdKJRjPsmnvebnOVtm51MtYno5iJvIs5BtRA0g9XEM?= =?us-ascii?Q?Zs38WX2KtnVIgl23GX261WoTASuwEa+XDZPRLTGPoxk6TbpV?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 39cdece0-8545-42b4-d2b8-08df1bfe6806 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 26 Sep 2026 18:45:59.1485 (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: 7sDJZQhd6yOVoRS+drHRbqMh/xB9L2gYKQk3AeSz8RWtmpB88bww5E+IleDVdghS X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR12MB9690 On Fri, Sep 25, 2026 at 11:37:09AM -0700, Jonathan Cameron wrote: > > +efi_status_t efi_drtm_prepare(void) > > +{ > > + s64 feature_status; > > + u16 major, minor; > > + s32 status; > > + > > + if (efi_drtm_policy == EFI_DRTM_OFF) > > + return EFI_SUCCESS; > > + > > + if (!efi_arm64_psci_smccc_compatible()) > > + return efi_drtm_failure(); > > + > > + /* VERSION must be the first DRTM call. */ > > Words like 'must' should be backed by a specific spec reference. > I couldn't immediately fine one other than common sense suggesting it should > be called to check we have a version we understand ho to talk to. /* * v1.4B section 3.2.1 "DRTM_VERSION usage" explains that a new major * ABI version may "Change behavior of existing functions". Verify the * major version before calling anything so we don't trigger unknown * behavior. */ status = arm_drtm_version(&major, &minor); > > + /* > > + * See arch/arm64/kernel/vmlinux.lds.S for the DRTM Memory layout. After > > + * the DLME we choose to place the Normal World DCE region followed by > > + * the aligned DRTM_PARAMETERS structure. > > + */ > > + memset((void *)dlme_start, 0, efi_drtm_get_extra_size()); > > Is that efi_drtm_get_extra_size() adding much? Yeah, it is the one place we compute the extra amount that was allocated. How about: /* * For robustness zero all the trailing space at the end of the * alocation. This contains the DRTM_PARAMETERS structure too, so * must be done before filling it. */ memset((void *)dlme_start, 0, efi_drtm_get_extra_size()); > Maybe it is worth keeping for the big comment in there, but it does > feel like that and what we have here could be combined. efi_drtm_get_extra_size() is called by the generic EFI code, I can't remove it. > > + /* > > + * DEN0113 section 3.4 returns from DYNAMIC_LAUNCH only on error. Boot > > I'd use a spec version for references + ideally title of section. > As much as folk may try, sometimes these things move around. I tightened all of this Thanks, Jason