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Shenoy" , , Kees Cook References: <20260320235824.GA1176840@ax162> <20260321163852.11102-1-kprateek.nayak@amd.com> <20260323093627.GY3738010@noisy.programming.kicks-ass.net> Content-Language: en-US From: K Prateek Nayak In-Reply-To: <20260323093627.GY3738010@noisy.programming.kicks-ass.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL02EPF00021F6D:EE_|MN2PR12MB4335:EE_ X-MS-Office365-Filtering-Correlation-Id: 9015be15-6ddb-4750-1d1d-08de89011b1b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700016|82310400026|1800799024|376014|7416014|18002099003|56012099003|22082099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:satlexmb07.amd.com;PTR:InfoDomainNonexistent;CAT:NONE;SFS:(13230040)(36860700016)(82310400026)(1800799024)(376014)(7416014)(18002099003)(56012099003)(22082099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: TU9hNGRyN7CftVIwKWZduMiBQwjhqhS/doUG2jub2/Ul/YJ4buB33QNDcmOf/+9sA67IzWVPo447eySWFj2GXZjCMbjQxHP3hGUy02GauLmO6VNdQSU6jUCHqMY/xfklcZ+EDwhXHFGP7DxESCS3Qjbw7lsI3JWiqt75tpMP8cSVnM4F/EnsYnzmYhu1bA34/pDsLhTWeyjZHwA6PH/EAsNVrnIZISpEeR9o+FXpNsXS0jMSS0E5d0yYN8MBgvv7SUdJBrYsgKUR9AUoZLf3r3m/x1dRD+5LdN2WGxC3wzFvP241Wt/mvse+FfPgLx0eEhgGOA/hK9dCdEDXykMmTaWTNFlSjVCAgt8sNXvxh6F6y6BT7VSXDKjiJDIgVDOwUn+hszB0LMMR6/AmqQKH+jM5j59+Ak9f+Tb4xUqFuSI3ijPksL9RVfxjdFxDglb6 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Mar 2026 17:24:57.5478 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 9015be15-6ddb-4750-1d1d-08de89011b1b 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: BL02EPF00021F6D.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4335 Hello Peter, On 3/23/2026 3:06 PM, Peter Zijlstra wrote: > However the way we allocate space for flex arrays is: sizeof(*obj) + > count * sizeof(*obj->member); this means that we do have sufficient > space, irrespective of this extra padding. > > > Does this work? Solves the panic on the setup shared by Nathan and KASAN hasn't noted anything in my baremetal testing so feel free to include: Tested-by: K Prateek Nayak -- Thanks and Regards, Prateek