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McKenney" , Boqun Feng , Jonathan Corbet , Prakash Sangappa , Madadi Vineeth Reddy , Steven Rostedt , Sebastian Andrzej Siewior , Arnd Bergmann , References: <20250908225709.144709889@linutronix.de> <20250908225752.872081859@linutronix.de> <3951a525-8fce-484c-bdc3-3da4e6160c75@efficios.com> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <3951a525-8fce-484c-bdc3-3da4e6160c75@efficios.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: MN1PEPF0000F0E5:EE_|CH3PR12MB8909:EE_ X-MS-Office365-Filtering-Correlation-Id: cbf5f9c7-4f19-4fa3-8e4d-08ddf153957b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|376014|1800799024|36860700013|82310400026; X-Microsoft-Antispam-Message-Info: =?utf-8?B?VTc3M0VPSEFMcDB2bHJZYWo4V3ViVFhGN2FTeHg0RlFhUDNXS3RHd3lXd3Jq?= =?utf-8?B?U2x3MGFRVDYrU3dYQmplZ1BlUTZ2dW93OW5YRXhTN2RVV1lNWnBNM256Uy9Q?= =?utf-8?B?eFVMMytiTmlwdnNLT2p2Nm1xVFpLVUFZRjk4WlRLKzFsVStPRS85TVRydWIr?= =?utf-8?B?ckZGUXVHT0dWMjFGUVV1RlVyTDFveWIxRGsvRXlLc2xyb3F1ekRUKzljN2dv?= =?utf-8?B?ZldYWWhtbjk4Tktnb2NISHlwbnljRVNBWU45ZHgyTVZSUjZWZzdweGtWd1lD?= =?utf-8?B?ZHZnczlWcjM4WTJldG1tMk5jS0kyRlVOOTlzaUZXSXBONEl1Q0VZVjJmRDA4?= =?utf-8?B?VTJ1TDZaK0JaZXFXa3dNS1Q0bk9GN2dqcEhHclRFWUpQb2RmcUx6Sjdib2dP?= =?utf-8?B?MlVjbnJiejZGTEh4bUVMc2UwMkdvbk85c3cxTUpvMllTVDYyaHNpcTcvNWpm?= =?utf-8?B?RllLK1FsTWJXdzY2UG93bU01WkZzZDNHVCtHQUE1Z2lWemhUdTNkNXJDd3M2?= =?utf-8?B?MVJueWZWS0ZJV3lMNGk1YXBHV0RHZHk3ZDB5UkZKd3NVcC9xSzFBdi9BYXdP?= =?utf-8?B?WTNFUHVIajdud3YrN0ZuMTRkYktKSWFleHppc1Y2RWx4YzdsaTROMFZlaXpp?= =?utf-8?B?NWM3eDlkSGIyaGNjS3RKdFJ1cHY3eEZBNHJSZUhFejczZWRXMm5aQnhLMVor?= =?utf-8?B?ZXZ2R3Y4U25la1RzNXBZV0dUVXJ4RFZFL1hMMXlsMjJlUlYrSUdYV2J3QUp4?= =?utf-8?B?S0hEckFmVGlPVGRiUGplUGNaNUU4dUZraTBWQUhiRUpZdWZkcFduVXJDdE1L?= =?utf-8?B?djhQLy8yZ3RHOWVleWcxbDRaVWd0QWFJYVVKQ1l6enl0U3R6TFEyayt4RmUy?= =?utf-8?B?c0pWRmw2NC9rU0FEZDRjQW9CQmNxcHp5dnZzLzBoTkJkdWFQU2hWTGl1UmxF?= =?utf-8?B?cVhZZTlIMTh5SXR4SVQwY09VRmplb2FmeU1vOERseGVFR0NMMVJ2ZUdseU9Y?= =?utf-8?B?SkU3aWJHcmhtMnlTdEFPZS9Nc0t0QmVRRklxOGFscU5meFZaVDZwSzQzRi91?= =?utf-8?B?cUFWOE5iT011ZEVKamo4dks4eW1VNXA1SjJBVXJnTVdLYmlCRzFsMXFvVHM5?= =?utf-8?B?ckVYdkN5QlN5NG5uUnRXckxpSUw4aGZJaUFmSWdPYTV4RG4veTRnMzJIU3dv?= =?utf-8?B?SmdLMGpBTG1yMFJtUjR2eFRoQnYzVUJ0T1Q2bzJqOXUxUVB2ZzRYS0M0RWl1?= =?utf-8?B?ZnJVWlorVy9JUTB0L1U4azBzRGV3UmpaMnZpM29VaE1xaFZ4M3pPU0xyamJq?= =?utf-8?B?M1RFVUd1dFRDNHFETmk3enI3NVI3RWErVzRMNkJxNmJuQ2dtK2NjdG5Famgz?= =?utf-8?B?MDlPY2VFdENIVzRvQXhhUEJvVllmRFNzSklibmZLRG9oOFNMUlQ2MTlGd0dz?= =?utf-8?B?dW93L2s2MXhXR0djVW5ncHk4SHVhajZHREZwNVp3TEJtWDg2ZmZBYlFJd0t1?= =?utf-8?B?bXM1SGl1QzRhZXM4c0Y5Qm1PLzc0dDZYTy9FalB1SjBUd0VMaWRjejZvazl5?= =?utf-8?B?MmdmRlJzU2xSN0I2Tit1cGttbUFzV0wyTk9GN0x3eE1KQk0xeFpOUzYrUDhl?= =?utf-8?B?SjNtNWdSdmZuOTF5YkdyWlRkTERCS28xOFc3K1Bvbm1CNUw2c1V4UkVUSFIw?= =?utf-8?B?UU5DSVJIUlgwTDlxVlJvL0hidWdybW5tbllVTFFlNk13UzFuaHVVQkFyUE13?= =?utf-8?B?Kythaks0ZjFmQlBHR0hxZEFwZlM5VnBFWGJLamFPOTRTY1NjbUxnWHMvS2Ju?= =?utf-8?B?bHVtQ2NHT1IvMk1XaCtsakptc0JGaFBBREMzbWc1Y29KUWtPVnJOQnRKbXlh?= =?utf-8?B?Y2E3UEYrdnNkWjYySzZRcDRjZGNpclVLNCtMaVpZdHNGRHlVZ3oyUHplSERq?= =?utf-8?B?UkdWaGxYQkdkbmZxdkE2Qk9xMlBLbUZKeHdkUkZleGRuWnBLSExjS0k0MHlu?= =?utf-8?B?STlOb0hTK1lBTkdQUHp2SmZPTDFOK2RyeGVsZEl1cXd3aC9Ec1ZOR01BbThN?= =?utf-8?Q?vz0T1d?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(7416014)(376014)(1800799024)(36860700013)(82310400026);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 11 Sep 2025 16:52:24.8527 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: cbf5f9c7-4f19-4fa3-8e4d-08ddf153957b X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: MN1PEPF0000F0E5.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8909 Hello Mathieu, On 9/11/2025 9:20 PM, Mathieu Desnoyers wrote: >>   +int rseq_slice_extension_prctl(unsigned long arg2, unsigned long arg3) >> +{ >> +    switch (arg2) { >> +    case PR_RSEQ_SLICE_EXTENSION_GET: >> +        if (arg3) >> +            return -EINVAL; >> +        return current->rseq.slice.state.enabled ? PR_RSEQ_SLICE_EXT_ENABLE : 0; >> + >> +    case PR_RSEQ_SLICE_EXTENSION_SET: { >> +        u32 rflags, valid = RSEQ_CS_FLAG_SLICE_EXT_AVAILABLE; >> +        bool enable = !!(arg3 & PR_RSEQ_SLICE_EXT_ENABLE); >> + >> +        if (arg3 & ~PR_RSEQ_SLICE_EXT_ENABLE) >> +            return -EINVAL; >> +        if (!rseq_slice_extension_enabled()) >> +            return -ENOTSUPP; >> +        if (!current->rseq.usrptr) >> +            return -ENXIO; >> + >> +        /* No change? */ >> +        if (enable == !!current->rseq.slice.state.enabled) >> +            return 0; >> + >> +        if (get_user(rflags, ¤t->rseq.usrptr->flags)) >> +            goto die; >> + >> +        if (current->rseq.slice.state.enabled) >> +            valid |= RSEQ_CS_FLAG_SLICE_EXT_ENABLED; >> + >> +        if ((rflags & valid) != valid) >> +            goto die; >> + >> +        rflags &= ~RSEQ_CS_FLAG_SLICE_EXT_ENABLED; >> +        rflags |= RSEQ_CS_FLAG_SLICE_EXT_AVAILABLE; >> +        if (enable) >> +            rflags |= RSEQ_CS_FLAG_SLICE_EXT_ENABLED; >> + >> +        if (put_user(rflags, ¤t->rseq.usrptr->flags)) >> +            goto die; >> + >> +        current->rseq.slice.state.enabled = enable; > > What should happen to this enabled state if rseq is unregistered > after this prctl ? Wouldn't rseq_reset() deal with it since it does a: memset(&t->rseq, 0, sizeof(t->rseq)); -- Thanks and Regards, Prateek