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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?LNyja5cIImYY5wLvMXYqWJw34U+/zE4vLKtQKPyRHjvLr+XZgrhhatSB+Y2U?= =?us-ascii?Q?iWFVbvVQI3FZ9d6gxXeDCh1Yt++5DsgKBNUV7cd3SUA7R1KSb05ejBubZ7X1?= =?us-ascii?Q?Ddq2ypGhzc8DxfCPVHk2Ua2FaV7A+opbgV1LROJ2UKhmWNqGDitoOj3o3cmB?= =?us-ascii?Q?4g26qeDEi44+4x1f8XZG1c5k1rY/g4EhjAGlBYa4e8vv/wedpe1II+S8mzxN?= =?us-ascii?Q?MrF+ctwW+gB5NU3Oq/FjH7lj3n/gb+dLXgkBmy4mh0qOp0TuYc8oczgp4Ho6?= =?us-ascii?Q?Dq7Ej5uVMXh1NYxyN65/duzT15fwIMarJmkcMDcbo/Ew02KdBw3a4DAcxnxH?= =?us-ascii?Q?relJVxqaKt9tagexRz9lN2hSCRHEfx8hfcJv2TEhEuxzPkdOSfAz9NkU3VXz?= =?us-ascii?Q?VJJsBXW+hSiACJvDMXu/mETm3L9FSyMOzQlxa9y4DV/pBl/z42g7Wt3U3QXB?= =?us-ascii?Q?4dVPHuOlIK96PmGjukclCCbPlsrFOSR67Q0kBK9a3DeSHb7PtEtBRbbZVwgO?= =?us-ascii?Q?QE9HzA5xnxCkfKqCD2WJFBDWeQPCHN0EN/4M89tzhWQNrMdKSMEOCGwrUfye?= =?us-ascii?Q?wI5GpNVFsKYeTwa8aaV0J5GQcRmQEtryTIdTWRZxx2TaCe8iFi3kiZDrYgSn?= =?us-ascii?Q?uzCnEXWd064ZHYMNsoPu2ZHolNLaDA+i/siBWOYcdC5dE15WJyGNaoVkv9ob?= =?us-ascii?Q?GQ596a72d28TvcD5jcsC0OWo3FBnAJ3XtCEM660KTBCQZwO7bdy5SgF8eLSr?= =?us-ascii?Q?pnUv9FXRotZQg/jz+40ULjDzoPPgvzVilA5/bPttLLfgtDvgjpKxtb85KT3k?= =?us-ascii?Q?VVPfpIy2VNDDBRml0wZmXn8fIi4Q4j66XuxemUv2ra7YdoX5p8Fuwt/5t/NP?= =?us-ascii?Q?rw0QV1WFrh1AnOD/SZF8RpVfeCGztFUd/IZ1zYRqay0dTG/x/ZSI5s57ked1?= =?us-ascii?Q?QWzx7x2CI1NSQQbBA/lo5A5EriSj6sNYXekr8xJlhNkTwEf5E0isvyago6zb?= =?us-ascii?Q?Vrg7oTx0y9J4QuF2RttivJtesHNzCcBI7fNDSNv8QihGkxTSop+JmCES9Iti?= =?us-ascii?Q?VFvaO5eYaj2voxM5+BBlG3WmmYu48cATj3UAHwLhT7m6Nm8XZx6suJgD0IGQ?= =?us-ascii?Q?TBNLgKZdN9ZTzOrxdA51Z4kicHDMjJ+ZH9YhlTVi9boHO5Hqp2ZHj1wZ8YP6?= =?us-ascii?Q?pxh04DYyNCW9WrixtP4IjFfDkXE5/xrq1mgSleg61f7cfDgkjWM1X7hXaA+W?= =?us-ascii?Q?s+fb2HwwC38/uCSkjcJOXjV0hktlIZ19joil93cita5p+wcTMOilKkkWQ//Y?= =?us-ascii?Q?1JKPreqPDzwQ2Kd8tL/eclXXBzAMGY4pqnf0gKCeATCkORXd6Fkuh7xg2Jtj?= =?us-ascii?Q?3x8NR55QY2V4d6Vk27znJOM0/atk2J2MxKRhN7hBnGF8RDXatYVezWk2Pd12?= =?us-ascii?Q?p0ioxNHbPdKqFnUHSdpaAGEZSYthivxiz0Lkkrtwyy+wUZAqZc9rSaAUXPfk?= =?us-ascii?Q?uwDQ9F8fL6FnTeZWaU9XGoD91+nWluLq8xoLuNkymPxKn+tT5NkYil1toiyG?= =?us-ascii?Q?QjbGVZOsasW+jIBB/SY=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9887aa36-76b8-48ee-f45f-08ddff586a3a X-MS-Exchange-CrossTenant-AuthSource: PH7PR12MB5757.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Sep 2025 13:02:16.2343 (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: J3OqciB+8+GAcXVJeRetBP/yTzEJnIArhy5p4dpwkbDpBVoExkbZ1lUM5g3MrRbu X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS0PR12MB9323 On Mon, Sep 29, 2025 at 02:18:50PM +0200, Hans Verkuil wrote: > On 29/09/2025 14:07, Jason Gunthorpe wrote: > > On Mon, Sep 29, 2025 at 10:23:47AM +0200, Hans Verkuil wrote: > > > >> Since I am unfamiliar with the iommu core code, I am uncertain whether I am > >> just papering over a bug elsewhere, or whether this is really the correct solution. > > > > It is papering over something, group->domain is not supposed to be > > NULL at this point.. That probably means the iommu driver has not been > > It's group->blocking_domain that's NULL, not group->domain. Er, I thought you were hitting a false positive on this: group->domain != group->blocking_domain ie NULL != NULL But I suppose the whole expression is checking for group->domain already. All your patch does is entirely disable the safetly logic :\ What is isp_attach_iommu() trying to accomplish? It does arm_iommu_detach_device() and then arm_iommu_attach_device() ? Why? Is this trying to force a non-identity translation for ISP? Jason