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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?uL6iBiLfzQ1EEmHEPUtS7NBIkNYI2zzDA8CBa9I6gLEQwSamdYP8oVBKoX7S?= =?us-ascii?Q?4g9JLOlLrc5PEGsE3/LW/qtJAxoCZ8bJu29mxDRHYuwmRGp+31ykQXy/uom4?= =?us-ascii?Q?n5Z6i+/ygQaAUdQKK/jM9FeadyfWkVhYIBW2Oj2JZjxOCk68KdUVG+3RFrUx?= =?us-ascii?Q?QfHRSeOLEMQ6LVKu+7yzc7CbQ8HWq8EqmXBeFoRphET+QvLdvxAbl67Wnp92?= =?us-ascii?Q?KWmVd6Hgef91DgyGD4jQz5fdLRn0i+PayDngXxi+EHy6od0Z0sxHxKUUsljG?= =?us-ascii?Q?toyCk2OTGjC6mg1DWOgX+ABstieFQQBDbkFvpIxjZPpSW4u7ypbZrWqdFIG3?= =?us-ascii?Q?1S1MWw5aumcMOE9IK/+KGIv2/Dv5j8asoXDk7f+vzXbUslQGJcBY8KL78+Mw?= =?us-ascii?Q?XfQ7GAyORIy/adX3rXeAs+g+8DbRlCcXReBsW8pzBOH79rj+5X2tBGgMlHnb?= =?us-ascii?Q?GJvzivsVOVT7FtROsOb+29zH5ER5/BZsAgohvHvLjHKe3W730K3kZ4EbUQU8?= =?us-ascii?Q?yaL58pqPXCMVyaB+/7CbDYhKGRuo8U439uBWXcHvA+X4OtKFabUz97aykXpE?= =?us-ascii?Q?kgZgQRyFqqJvEBa9/u22l6hLScO0iZYTLN3SMpQsyCzCAcQU9cds6xNhpF9l?= =?us-ascii?Q?VDqxDOjO0MEJ7UQnPbgnhsSZ9g+G2mMBzeQCeB6CfqoP9BSIJmC7Sw/9Bz71?= =?us-ascii?Q?Fnf+04mBohw4H7yMfWcH/zRabW5iNNakGKHMRRsZ6kPeBgmQyTPZljtHojod?= =?us-ascii?Q?on6y7xatHvZ+CVI2xvtXbMhWzcM3ssfcAyOk6UskBKXlabuOG+BwNDJ/ByLn?= =?us-ascii?Q?I3/Zsjni+wSGU8TufwJIkZHjtdBBtAsZINzzZqYyTOEGj8ZFJKINKIdXuXXL?= =?us-ascii?Q?KjH53pugwhtqjAKXX5Id0ZX6+VaDP8dY479KB4OZQo/wFP8j73fLEwj+MLzo?= =?us-ascii?Q?/6d1wzuVKeol9TuzKSPUpgybXIYnv9R7VZ8Ohx6ShvrTek8Q2d8o+THY8y1s?= =?us-ascii?Q?+A2iCFwkp40MfTxqwksOfYhC5aK4USszfU+cZZdZY15AmNvJuQCQd6gqfdA0?= =?us-ascii?Q?M6U/IzwbSKofFCxVzGs1myw3O3PFEs4sBBvJMByhBuK8YpztU+/HsA6TY2Co?= =?us-ascii?Q?5NB/ubW2jj77Xa1NUOdq2xkJBIpVIdCa2tg9KrJ4+xNK7n3nFIVzCOSRVogf?= =?us-ascii?Q?7ozeC8AYOKZxYX0MgH14WJ+avU2REoJ9GCjbklxgH/V3Vycrvh0fp8mIRhPi?= =?us-ascii?Q?O+iL874joDd7QOxDXGTwE19yUhPgyHPjekMGwcaD7+9p+S3aEuu8Ym0GhTtn?= =?us-ascii?Q?V5s9uod2Ec2dc+yyipDjwjnDUhPy6JMtkhgYHTDtzQ105bitm8YOu/HB/Fbc?= =?us-ascii?Q?jVN92n4CY1VJyV80b+ovNROFV5ly5Zh7uhSkU/oE2SChQQqAdV87Z3qby1Hm?= =?us-ascii?Q?SEUHIqcGQFC8rLTzwajcsjUbCg/EInB+yYE/3S4imZuiaTjmjo8g0vMenEpB?= =?us-ascii?Q?6ZTzlGPESHttIKrea+42dJfOCYYCUyuleJn55CAsOh0bv/K4PKm0d+cX58Tn?= =?us-ascii?Q?mQ7w/PbVDPQRuJHLNDV1s5tfH7FF5zgN2UbeR5tTWo7wCkq81fmoAta2Faxq?= =?us-ascii?Q?cZsoHeXJ3oi/gyuvrqSNfNYlL5hxYbwlVDOPeNLyKMyULH3tISYdGrQ39In9?= =?us-ascii?Q?AR0qoebSZ4Vda5WWX1c935+ONjegfWJtUQwKYl/Coj5XZNfR?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d7570ea1-5d2b-4313-58c0-08ded8481240 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Jul 2026 14:41:59.0588 (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: ylMJV0lnIGhiHgaU/QqPAsdNLGXl1XJbtpqZtAZaOpjMJdOCro0s0agmHtyBa1Xy X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB5813 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. Jason