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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?GXT9Eek0q5VLB3yl5GfYTUUiEy8BGGCJbH3FiB3eCF28f8SZFSz8aORVdgDH?= =?us-ascii?Q?hkIq7OKSkY/rCoLaE0ef35zq0KQQxfGKWrVbNlP5CH1p2HPPA8h6kxrWS6gu?= =?us-ascii?Q?x7CspU2dZzVVpH/sJAvsedF9+gAkAWViQlf091ucAySYJb/oVXZXYljjbZFz?= =?us-ascii?Q?amdzOTHFtIx2Yak2AilbASjLFs1hg8XCLweVqjzHEnZQ0u008f9A8Qdh1Vnk?= =?us-ascii?Q?Kt/Qo0v9TB2J5jN5c/bzgPttmWl771741WZqDJXrLRvvq3n8wDov52QimGxE?= =?us-ascii?Q?upOJqz70ua8rmmszROoiHIAb54+gbj/AA4ls8nCyAPaS5yUR6M2vxrEaQBWH?= =?us-ascii?Q?3kIUoJAPT4ITw9xIK/tTL9k6ID3sLOuooVyFomTNE+SuFkuj/XGGf/5E25oK?= =?us-ascii?Q?Qnc1w3skMRUfzlaL+l2RJBnRlaK6iNvoNTATvRkXI41MOFZKDpwWAcgYSBiU?= =?us-ascii?Q?tc4ow1B5Hqlv+8pijXmL+k2faPhcl3841L0ucdodjGu1Y4/Ir18kd/3b8ZK4?= =?us-ascii?Q?q50V0u1uoJInZBzRDvGAZ63GDqrBUcpwkhxYCQMTuhIFlksw4WVOZlQkaB21?= =?us-ascii?Q?skU2gRExqkZOPx3EFMonpXDtqcbwWe5enxbXZ9Ql6zk7GCr9wPlsnOWoWgH5?= =?us-ascii?Q?X3J+I0dYWIB9Gc+rtRr7WL8d2tGus/YeJJwp5yYcO74gnLX1Qd7r5mTYfY85?= =?us-ascii?Q?V/WwwVvfUNb8bCMzTXAR30rsq/g7xVD2hlZZ3c6ipnDZfPeamju/2brYrnoc?= =?us-ascii?Q?t53y3n8Bs7GvOR1AMA600IQy3qtNbsoaiEScE+9447aKfZUQHNMo7m4FfyRG?= =?us-ascii?Q?vSIT1i/VI0r5K+k1Qh/HnlXokE+z2UNVMb88Li6JIb5iTWWhZ+DDL8TRxsZ0?= =?us-ascii?Q?PlLK2Ed5YFcphA5QS7IB07nt7rO/HUjoiU2t98ZqRDelr80oncW/q8D3BfIW?= =?us-ascii?Q?BTPRaomtPSmBOMPyMzQWtCYHUmRyHCrU5XTk5LmB/LwqyFYc4JwDPaFpvOQn?= =?us-ascii?Q?6Tp2y+vhOUpxl/j32ZEtRh0fLD20zUMqWe88R8/z1Lyor9coxwdFvvZ/DMDi?= =?us-ascii?Q?12QKWb4xhresM8aHdSmijfO3VswpzSj5/qGDSXI56fT5IjdHjoybRfvpsZPK?= =?us-ascii?Q?RoOwMpfphwVyvr6nfovbd4d5MqV8uzWnkyXzhNRv69EsXbtLiRMdMI2OwucP?= =?us-ascii?Q?v1Fmo5YCTmWC34T7WlNN0y4vVo73q01dht9d2W/rlRWL4sis4FFPtZR4Tbc4?= =?us-ascii?Q?GJ/JcWoizDIC1sIa1FVSLtuaTxXDHSloaFhvjoGgs6CNoIsyZAyA2SU/WtHc?= =?us-ascii?Q?oI1VpxGerrKOcQ1zBPTjfiu8tShZVNhx3qzpRcf6hSW5XLkz0in1DNNx1f8W?= =?us-ascii?Q?aLgeeu2vi5gffslvBMQFulCYTWnkMkzL05OBXm9mL1T0uxh/ptSz3NWBfIXB?= =?us-ascii?Q?1JYMExPkER+LSKcnEHjRoyuUAAvolTIjVWJ9pBr61ZV4K6dhJDSfDoAKOvVL?= =?us-ascii?Q?jfNobcDnBmp8+xBAXtdK5QUyL0qK7G++5GTwS+v8OJFesRoRY/d2LSRc1sfw?= =?us-ascii?Q?NtjFSfwGq17x53XYLvuMO6Cbo51saEgBIdL1BYGiDx3y5ypbl43AZxB9I1i9?= =?us-ascii?Q?5CMQpmrvHGmrvxarWB8SEZAxFqJPYYBf/iSoKsOhU0fFWRUlsj1RMSucmt8D?= =?us-ascii?Q?EB7CkA+/IdTi5oSEvRCktAIUelBj0tEx8mQeMthoJzqLB4km?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: da36919a-1ad7-484a-fddf-08df0f496af6 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Sep 2026 14:40:11.2387 (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: mFl5hUXxp186U3YqxpXG/oS34wwgE8NJKIV43E2V/KSKdXI2gVKOJWSEfkQES6y0 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN7PR12MB8132 On Thu, Sep 10, 2026 at 02:26:53PM +0000, Pranjal Shrivastava wrote: > The iommu_ignore_device() helper was historically called on device > initialization failure to clear the primary Device Table Entry (DTE) via > memset() and nullify the rlookup_table entry. > > However, clearing the DTE on probe failure is problematic: > 1. During normal boot, DTEs start out unconfigured (blocking DMA), making > clearing redundant. > 2. During kdump boot, pre-existing translations should be kept running > until deferred attach rather than abruptly clearing them, which risks > breaking in-flight transfers. > 3. Writing to the DTE table via memset without flushing the hardware DTE > cache risks aliasing & torn writes. > 4. Clearing the rlookup_table entry breaks interrupt remapping for > devices that fail probe or operate in translation-less modes. > > Remove iommu_ignore_device() entirely and simplify the error return > paths in amd_iommu_probe_device(). > > Suggested-by: Jason Gunthorpe > Suggested-by: Vasant Hegde > Reported-by: sashiko-bot@kernel.org > Closes: https://lore.kernel.org/all/20260529153216.2AD1E1F00899@smtp.kernel.org/ > Signed-off-by: Pranjal Shrivastava > --- > drivers/iommu/amd/iommu.c | 24 ++---------------------- > 1 file changed, 2 insertions(+), 22 deletions(-) Reviewed-by: Jason Gunthorpe Jason