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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?WSmFnDPMJjDXYgIDWj+HdFw8bpDC8+/z7kWy9iEcRf/FbaOly3plJi1NlqUj?= =?us-ascii?Q?xgvYZ/4uG7t4dtnGZU7d8smJDt+cuApWYFfodauSzJeppPMg76p5Fiqa5Ncw?= =?us-ascii?Q?pqvljfcii2+6w2QVq+QwWE7VwVgO8pRLods3vH6TJJfK5y7mES4Nj+NTRhKu?= =?us-ascii?Q?dGdORrFaEoq52dMwtI/Lo+ScJxNuoncHfWMQUrtbHHHk7DbYvTPorsIyTiwc?= =?us-ascii?Q?ybEBj7FVRVuQrzbgy8zTzr5Rv/SK1ZNmgMHCuVrul7taORPDj5KD3eY/jGxb?= =?us-ascii?Q?fshJpYHRbLwnKpbQufaeXZhhLTpiqlD/GnSBBeTB0hCStcGn2E6lcGxsJ/p8?= =?us-ascii?Q?PGu6rtNJvyB4iDM9kOi5+Ys3ZXnWSlG72C8l3wxWUIX9tGFlOizaBZgWDgbI?= =?us-ascii?Q?gkaxUOPgB9gtenout5btR15+RASjMgaqV7jPEszJ0iv7DzHg7V5XFu2SBxgL?= =?us-ascii?Q?tUw2By0LFK9/dLTGFd9GYpPloDUcS1JLLPCTFmHWx6h9g3uslcFfGKJKWLxV?= =?us-ascii?Q?GNurYEbTRSdqolGxv/ucJjXFsV2T4J/vX8PhlszGHavrcWgTaM8qqlvMgNa6?= =?us-ascii?Q?0LCpmkkZrnHQ02IVwkPwRb+rXahiKzj7K/bqL7tCsi1KrpKgAwwxP4e7oQ0F?= =?us-ascii?Q?l6G+VXaAgC0w5mB5fj6Pv4Gbkq0JXgIthBPKBoQg0iZYmh7kGkoMZI8sYfbz?= =?us-ascii?Q?ZhZk15EfB/GLRah2azOMbA/XhvEViJN4tZmgqwU1FnYD3e1tXxbILKHaO/BE?= =?us-ascii?Q?x401KHxqHxJLZOKeh4Utq7CVYgJAy6AuzWwq4ibxWM5bD8bzaKCysEESsh3V?= =?us-ascii?Q?mjrY/HwEQgQLqy02GGS+I3zO2tdMRv6FRASXkRbJsyLVmLnNriw5zivR/VEK?= =?us-ascii?Q?oD/tQ4FXnQiLAHbtG7ab1CpAppWWthiL1FYYPHfZzPLHddhzYGTW8zy2uchu?= =?us-ascii?Q?zVWF45vPc/25BtgXCMdum4UWQHtQ01ErGrH9Sdze+IDZ87L3QW1oL1OpFKDC?= =?us-ascii?Q?pzgo3DFEaAxO0w6ajPM9XMiXdHdGFPycRpwMDWmVBqLIq+Yh1eDs63El2SWb?= =?us-ascii?Q?x60QacfEQPYNv+9T7n6h2vPKnWj1hLIjtii7mZq4Bg1jr74Wew0ZLAu7w/wr?= =?us-ascii?Q?jVEq3kZgkBXnvdV8++Zf6bXY6GulH+D6oU5ikZ14cvbgORQKjL8JbLSULYXr?= =?us-ascii?Q?KGz0jhGncKzd57mg2wjdH3WyoahzyunjKPhk3Z+0geAz12D8DLgpg06N3dHx?= =?us-ascii?Q?16RZq79E534OskJ9Eynbkq6j9cjLbzwIx0UfaWsE9Q+Vv1uJy6TjpWdLwg2f?= =?us-ascii?Q?pSs3iT+rnQ2AKlwEbBR/ZtDQnM7aFCMdSarCIpQrhnkM2J+G7N4GikKWL5Sj?= =?us-ascii?Q?sb239cCONid08cjXLiLpvbjRurP3tZ7GuSg59xCAvrwZTCfsV+gJlL24D7K6?= =?us-ascii?Q?WS5EgqO7b0JOPO6LrgUT11MX25omDlNqE5xM99D2DWQWgVoY2MvbO4zCGaz8?= =?us-ascii?Q?WGWln5CB+79QgdLJk3UyJuNlbFdrcZHZaLwdGHl7ZMBiqaM3iAuapx5b7o7Q?= =?us-ascii?Q?8q04rDvy7+DpPLQoTKlmYe1rQnstom9FTwVK7AjdGYjfGh+hFwCemmUXk312?= =?us-ascii?Q?Dr+ywzdWqUqk9yGSzALDCxzqqnfLlPpaWdgRCLcoeafgUDh7esTjkX22aLQA?= =?us-ascii?Q?0t+HVbzSJ9ou6gm4hG1I2LmKO+09qUspuvKBdkY6A0MvAVuo?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4c60e239-9d11-4286-bbe8-08df42ab6843 X-MS-Exchange-CrossTenant-AuthSource: CHBPR12MB731189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Nov 2026 00:00:06.6799 (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: vS0zo+EzwEMgz3cpqUfKsYONpdgupQ6RWa2PqCP0s0SbuX66w9De7JPYNuFf6zUR X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV2PR12MB966079 On Fri, Nov 13, 2026 at 06:10:25PM -0800, Andrew Morton wrote: > How does this look for an altered changelog? > > : On x86, a shadow-stack PTE has its ordinary write bit clear. The CPU > : rejects ordinary stores to it, but pte_write() reports it writable because > : shadow-stack instructions can write it. HMM consequently sets > : HMM_PFN_WRITE, which Nouveau turns into ordinary GPU write permission. A > : process with GPU access can then overwrite its own shadow stack, > : potentially corrupting return addresses or bypassing that protection. > : > : Reject shadow-stack VMAs in hmm_vma_walk_test(), including read access. A > : requested fault returns -EFAULT; a snapshot records HMM_PFN_ERROR. Yes, but it is not just nouveau, RDMA user can do this too and that is far more common.. Thanks, Jason