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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?9cCgkV1m2SDTRsXE9d+8axWNhdFNHKTyIQ9dfPl7g3hNdztFhjq9wVMbR904?= =?us-ascii?Q?naS7FXVQg2i4rhxdIDG/ZtrZ4QCNnP8/4sYQQ/BGkGy2IWjR3ery7K0dRlkY?= =?us-ascii?Q?qpTnnkRY4ZgIFBnBr1w3XRowODun5tYVssAGv++l7I6VT8Pt3nSW2ZVkng7R?= =?us-ascii?Q?0wXoMNAJK7ewN2/TcwTv5DeAmhUos44sPR9cxARZ4YVz318LoG2IFn1btkaN?= =?us-ascii?Q?ZyMKjSKPtPFxqVUql2ei1LB69QRHwal9zBQBczttj8VOvhp2XaK7XFiQLkSw?= =?us-ascii?Q?ZQTUsM3dbdjQgETx6J5Ifbwpin0k6f4Bop+7aKGsvlXKIy/A8d1587vHMwR+?= =?us-ascii?Q?S7wCYhrTm0dzH2wFmQYfg+0ny4t1d6Dgd/JMovREcSdd9vptweKAJrIvN/7B?= =?us-ascii?Q?zZQvtk8dM/7nuDwg9angvQU5OIkQic7E0zFvZ2C23sFsKcYDIu649+KQrV50?= =?us-ascii?Q?XHxS2ADqIuGJzLVW4xGFbIdQQ6hsNBN/xrRCBIPqc2uKBNAKFDmr5iPNGP/V?= =?us-ascii?Q?ellQ8rNo9cln+F0WcB4yrXQBpsli0fRioo+qWXXF5WTPC2eXunP1043c57hI?= =?us-ascii?Q?zvOpvJz7x4v75IKxZu9EjiLZfQ8EHiwzGZtNPdK5HWY0Yv7oSoUvrr+ZGopT?= =?us-ascii?Q?4ekbLwo1iPU//HbxdBnszJD5bd+EY3lkHObekXbHLV6GGI/lUVUL561VlkyG?= =?us-ascii?Q?wgqgWD4XKvE53ka/Xj5+WZROWIwx/2iDMZPLQSrF2iBJwzJgS2YibWZIuZm5?= =?us-ascii?Q?P+uMcygiLQo0CNm2d7bmH9d5SGNvzJrIfe2AqYg+lawIvWBpdkpy2lUOn0Bo?= =?us-ascii?Q?IK/drI4d7qCdVHmVqM/Tgg41UU5mHC/e/7uLOQPuIjy8E8qTd5j9zij7055q?= =?us-ascii?Q?raGg5Bkv6MMwekBIlqFj8mlrepsYbAthCJgf50WJiV9cqp/XHb/vDbtnBTjg?= =?us-ascii?Q?IDBH7WFDraQsH15PQ6M0KN7/y/sZ1fky1yNBjnI+j013keEvao8b0bliybN3?= =?us-ascii?Q?+LsmrGfLPL/oiu7sdjbfFFIApH2SKwXX7fPFdInEyZ7k6VkZ9msJdEQjMyQl?= =?us-ascii?Q?p6+1sVuMVe3QbT6VoTjdb8q7NFv30NrzvracPNCJz2BW9PtF+JF3qCgHO7DX?= =?us-ascii?Q?sqdotBXO1fcCTt+aJUlxfSXXXRV216rBm1716qg6mrlAhgubkbbFQ00DIXRD?= =?us-ascii?Q?C5MOOIJQnWuiOB/PV2hsVXyC3mTefLdqtbMqbUs3dkrEmACh9m5p+2mnzObS?= =?us-ascii?Q?WFIi2AngfUO4cxIkvCZIoN+7D/naEI5nAgzPlTIatYLA1krmjoNNePAy9XsJ?= =?us-ascii?Q?MAHq6UC0B3dtaGYVvwIKNGLwTiuVTB+Us9vXtf/8YVYSvcNo+AwYirMAPUqZ?= =?us-ascii?Q?1N1RrvBYKAtYdlAIVGNX1YoaR6riLCQtc9vuIKCFQvnsahfP2bRBNlWdEtRw?= =?us-ascii?Q?EHhgF/ApZoSBjCuYGmCuQ1X3Rbcx1DDeHbWlbAoHesQmiAQoexZ9hCf2Op7T?= =?us-ascii?Q?uAhHkh5GqsL5q7pNmt7ImlKkayhgWE2hgZyVqOj+Li5+2zELa2y2oX8D9Nuf?= =?us-ascii?Q?SONZC0u5Ud6C/9Iyk5PgGW9Nr5Zi1gidcxSwYRAC3tzPqaqnJG/AzmW5Tjgf?= =?us-ascii?Q?yKjo8mG6CivB0g1gi+rrphMbpQ7wi4VtE46dIqxjx2EoLgDfsKN8+nILcni1?= =?us-ascii?Q?bcKU/DFD51DBA/tn2AesPoUV/KQBaXAWvipitEUYZDmMtwfg?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: aeca3b70-3b52-4035-5e85-08ded894a44f X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jul 2026 23:50:05.9914 (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: Zp3fZcfc4LCozAxv4KKe/wp/5yUzjILEHyV85v342zM2fNCJ/qtk3oIomlqux17b X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB7744 On Thu, Jul 02, 2026 at 12:25:43PM -0700, Nicolin Chen wrote: > On Thu, Jul 02, 2026 at 11:41:57AM -0300, Jason Gunthorpe wrote: > > On Wed, Jul 01, 2026 at 01:36:29PM +0000, Pranjal Shrivastava wrote: > > > > > However, I agree with the overall problem, i.e. IF an active device > > > unmaps the DMA addr after the transaction in the previous kernel, > > > (with the SMMU powered ON) but the TLBI was missed due to a crash/panic, > > > Any new DMA in the new kernel may alias onto a memory in the previous > > > (crashed) kernel, not the kdump kernel. > > > > It looks like there is an issue in this series, it isn't doing > > anything with the VMIDs. > > > > The VMIDs that are in-used by the adopted stream table have to be > > removed from the idr as well (and similarly for ASID if we don't have > > VMID HW support). > > > > Then the VMIDs that may be dirtied by the prior kernel remain isolated > > and are never re-used by the new kernel. When the new kernel wants to > > do DMA it will replace the STE with a new, clean VMID, and there is no > > problem. > > I see. I assume the reserved VMID for the kdump kernel will be a > clean VMID (!=0). That should guarantee different cache tags. You will also have to change things to allocate the kernel global vmid from the IDR, it will usually be 0 but not for kdump. Then you have to find all the places where the 0 is implicitly placed and put in the actual value. > But, do we have to scan CDs for ASID? I wonder if we could limit > to ARM_SMMU_FEAT_TRANS_S2 only, as this series does not memremap > CDs at all.. Yeah, I would limit to S2 for now Jason