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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?IhA8IWdA8pnNWjtscb0ONdHO6Iiokmf7iCNwt2HsCpBucKSyaC1Cz2PUuMcX?= =?us-ascii?Q?hh4/LNJqe7+ZD0MHEx/x/IUgtx3aYsbv1Io/CjHrQdPAHBpP6hfSzucGAwjV?= =?us-ascii?Q?/CGOA5tnvIL6N8NNdnwWBGXmJhwMj1qkRS/Yd2RXOJxXZbNIc3TPBqHbFN3f?= =?us-ascii?Q?QO4ty0Am+9DVLaU3JZEyvYBktUx36Hu0h7REODzImVUrVhAEPGQPxfktEpbI?= =?us-ascii?Q?Q93UMAw6MHVi8EYGe0TFaCsM/Q8QN1cw/u2pRQGLlbEHli7/n5G7kDTpx3bN?= =?us-ascii?Q?SQZptOFAnfgQ551WtqDOXXIkHYaxs4CCgYrhWWh971CQG7ahAc3pcgyAxG5H?= =?us-ascii?Q?KimX0YccbgljMbyhS5ar2pKpgndflp3ThupuLhdhaW+DxIrkbJkecIdN2pIe?= =?us-ascii?Q?6dPj2YJF6Vjjaekv3Jo8QMJx0ucMcfrRZDfG0dLDimE5UCxhnJKZlLD7E3CN?= =?us-ascii?Q?6XN3MzWG8qoi0ndd56sO+bRbliMBDKjm+StmEMafilhFM258k8X4kpWu5+3v?= =?us-ascii?Q?Cwl7jWefgiaik825hgI7zDescxA/eMh7UmrldTnl9qLf2AsiABWXhcmml9Ao?= =?us-ascii?Q?Ifhn+etgs0hkmjZmn6IJOh7bDZhxpgfYxmrwyQtHUTFfmaFVXSSEN+kR/Gqu?= =?us-ascii?Q?fh2/ZqJjphKbCSumbr9T9zv4txzj3KltVS6yZ84HbHVy9F6Mg8mbp4fyRpWq?= =?us-ascii?Q?T6gsHw1qEoHUpES8t9XJP/5PPTCWWfgSjfjECoqsXTekuIYFaXx304hBa/0Z?= =?us-ascii?Q?ArKAlosV1dF/ReJkblXf8ylDCPpdZkbbeOu6JM/mzMGbm3TXx7OL0toYT+5A?= =?us-ascii?Q?n3dsyA5s1uV7mHbgE2sFddw+22hS0hsPiRDb9CIv2plxvEeETiYbRzHzd3Gr?= =?us-ascii?Q?kPlmbzWcHepGjDYDuRAM+0ckmuxD6PvaItPoXkD+4/Hy5rUzxF5ULcsh0Q0i?= =?us-ascii?Q?SqF7D8ZRNtyyl8cza0x8Sinfkow+du7rgfCeZ36XG5LCZM2kjQBHUNvbTeMG?= =?us-ascii?Q?gyJBlfYFCvo8gsqQcy/AYlOXv3l2VmsYvLN2wEN1fJJqFZolfdslJ4Xugk8c?= =?us-ascii?Q?qYjFMb1NRvM/NkftBTcM5oWt6HD+kwOZ+bFICuyUBpkfy0uwLw/rZNZVT6zF?= =?us-ascii?Q?DGLSCUEtZm8RcAtCMaYznQrYT9wU/HPfBl9FaLZt2XXhS00+qNoJuYTWOe/l?= =?us-ascii?Q?9bt7oD8crOvRSnYDNQrNmEa0pwUHy4KFbOED5cG0Rf7bDicT5I9Y3IB3IrvY?= =?us-ascii?Q?haAaOy+y3KglMgUUP3a9iYV03ciLWheZpDmL/aP0pEPKPjEl8BQ4l08401g9?= =?us-ascii?Q?6Nauxj95uAe1E7VpfVsECKnZIOC6D6fKmLow+ywiM6eubCwcokxy8ovzugPW?= =?us-ascii?Q?7QyiarRCgaqI+9FCEzg/Qnx05SXZN91NpqlI3DC1tjy5m6x0ZnjH7elVKKyO?= =?us-ascii?Q?pLKwxneq7aPZRXogKMK6I2rm0koG0J9EO/gNz+kPdb6EaTQNOhZRM+YhRsj4?= =?us-ascii?Q?5s+dqf2pLoDMHCHt4NPQZxQj1ycRSxuN77vZw7mQsXscJ/G/rQOjPHMAMIUK?= =?us-ascii?Q?FBtsE/QusZ/yQxbLeyM=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f4678395-eb1a-40a6-8da1-08de05ca8387 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Oct 2025 17:54:08.2656 (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: +4XR6j/XjiUqSNAzC1BqNp1/ycn+ULEtRlpOpiFa3rdmSOZ2nvVoO56ZQuYJXDFt X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV3PR12MB9410 On Tue, Oct 07, 2025 at 01:44:54PM -0400, Pasha Tatashin wrote: > I'm wondering if this work could be used in the future to expand > page_table_check to support IOMMU page tables. For instance, every > time a PTE is inserted or removed, an external state machine could > check for false sharing or improper logic. This approach could > significantly help with preventing and detecting memory corruption > early. Yeah, we could certainly add hooks for different checks > The main requirement would be to define a common logic for all IOMMU > page tables. For the existing page_table_check, we use double-mapping > detection logic [1]. If we were to implement something similar for the > IOMMU, what kind of logic could we apply? Mostafa did this, which is pretty similar: https://lore.kernel.org/linux-iommu/20251003173229.1533640-1-smostafa@google.com/ But he hooked up in the core map/unmap not directly in the page table code. Jason