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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Tht6KlZjfE8tnXC7IIOH+Rmb2i7iS/Lav9yOFXZRVFK8hRO9BymGOqJ5EwwC?= =?us-ascii?Q?CVQW0hgb5/W7Lx09GK24EqUNHmZj0ZKPy00CiY0r0hwIL+LwOyzM5riLmI+9?= =?us-ascii?Q?TbDC4d6hqBgVgxUszFDr4ZkiPwdSIPXbA39xjFkpvgS8I+nVWuBqT8Nn/Gsf?= =?us-ascii?Q?AwVmeauR3HE6bOB3t6EyEgmNI+VJtxfpDgerpOx7MWXvh6QHDlyH2WAfrU5P?= =?us-ascii?Q?tc4i708yMc4zDLPdglmm67CCR9A9jVhXP/GEz4JbZ8i8tjIAujg6AeTfV70Y?= =?us-ascii?Q?6kEPOHtxk1m3DUGYxxem8v0lg+CQwaS/o6QX9B8P62yBi0SZ4iJXDAm1m9V+?= =?us-ascii?Q?+ZprChIJ/UGLqJltIONif16pDhuaqpLW+4YaEv08sHNbqMoCRXAT6deLr6sd?= =?us-ascii?Q?k/rOcFmyjNRG/BNdrTqhJTyjvCdGfbhFgaMEp36SfTQkondGI3vi0SI/yajP?= =?us-ascii?Q?72Ni4twfOggfrcxMByUSYDn8lHX/p8RfRewljgdSLq16n/v+TRS5hKykvAJF?= =?us-ascii?Q?OF+4ckqTjvuLUayHd/UjMEqOMZtTeiAbYQKR2oVF4gaMQkCT31kijrLTjAuh?= =?us-ascii?Q?RLp+1tusQr9BKDhfbdmIQJTnbt5mupbTo+E1S9rBzbitTX5mMjDM6TNbxxfY?= =?us-ascii?Q?Si5/+D4j/S4LZS4SZJnUfp87HPTZuOCCF3b19ghXhKY/zMWrgt7aQlrKk4P0?= =?us-ascii?Q?9NRo0hbghRjMn9AA50XdYXfUIUrylpt9XWYWqz89BZiREYKRp3nFgenqom1T?= =?us-ascii?Q?o5JhsLwQ5BazCN2nUsfhdQqwqMN9xu+uDk1bmSAQqOu1A2YpaWbO78tFrezi?= =?us-ascii?Q?d7ipVmjcDtYnR5ZgNYNoA0RItL3aP9YxzandpgpOcrpIiptGoC0/YVT0VaQ2?= =?us-ascii?Q?ipxmBAZuX27PDsfQ1+A+k1QASeN9cUj6jTZ6nSwH3xKfyQiwzBgWHKyPL0CJ?= =?us-ascii?Q?IweELsAmEYgbpLuQnGE9XgseBfNjOA6wWGhYtyRdpxgg7O0FufeEjO5qsdWl?= =?us-ascii?Q?MyzaAnldcZRF1BFPs8MeopgJ05FeTRJDHmyh/PSQikVjq3Xjp6QV2K29L4mV?= =?us-ascii?Q?T9HFa5joRLhYUV4Sb6NKjejbAqLEuLFfJ5r9qOoBz52AxpJv0fEXQ09OZ4o1?= =?us-ascii?Q?oSf7avL0YdUTJTemKB58HxWxmzd3d2AhWW4LAWkHsqMX9+wnIIf1daBNA4BH?= =?us-ascii?Q?dY8v1x3Lt3i7KIXgZ9wUY1rWmYvJfsUFLbwFWODbHxSYMlQevFNodTL6mxZZ?= =?us-ascii?Q?jqV57Y/zmu2Bc5c+BOahgKCHan0oA++xcAwD1DDr1SMMDcpt1/9a5ETAStGp?= =?us-ascii?Q?SbPYe2sbtvANasQfgR3dTlJNgDRMLw3WhGBnwewMOMGMBlqPzzG0R8ZUxVif?= =?us-ascii?Q?pRvVrqyHQVGBXHptPMeiGVVt4szYeSbw1B3ZMqNxzCKlqGD5L447oggaAauo?= =?us-ascii?Q?gkCfqviiaWGDRdJjwCJNb2732Bc3uBW+cS5bTt0Eza45VE4io66GObbrLen+?= =?us-ascii?Q?VEQWBw2qOcvsQnLFZBaw1kJAHDQBGaZWrf8MHr8EmX/ueWilK+8MN1oDLuOQ?= =?us-ascii?Q?UX+NnFv+9ivi2lTA8Qs=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 4c793da5-9c5c-4a66-beb7-08de2c57e037 X-MS-Exchange-CrossTenant-AuthSource: MN2PR12MB3613.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Nov 2025 19:21:47.1406 (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: hkf4CM/nJgLyysFQf4sjWLFtNixh6m0y/fabGWJumWvEfBvf6qTqpZ8wAl5ZXklm X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR12MB7552 On Fri, Nov 21, 2025 at 05:57:30PM -0800, Nicolin Chen wrote: > There is a need to stage a resetting PCI device to temporarily the blocked > domain and then attach back to its previously attached domain after reset. > > This can be simply done by keeping the "previously attached domain" in the > iommu_group->domain pointer while adding an iommu_group->resetting_domain, > which gives troubles to IOMMU drivers using the iommu_get_domain_for_dev() > for a device's physical domain in order to program IOMMU hardware. > > And in such for-driver use cases, the iommu_group->mutex must be held, so > it doesn't fit in external callers that don't hold the iommu_group->mutex. > > Introduce a new iommu_driver_get_domain_for_dev() helper, exclusively for > driver use cases that hold the iommu_group->mutex, to separate from those > external use cases. > > Add a lockdep_assert_not_held to the existing iommu_get_domain_for_dev() > and highlight that in a kdoc. > > Reviewed-by: Kevin Tian > Reviewed-by: Lu Baolu > Signed-off-by: Nicolin Chen > --- > include/linux/iommu.h | 1 + > drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 5 ++-- > drivers/iommu/iommu.c | 28 +++++++++++++++++++++ > 3 files changed, 32 insertions(+), 2 deletions(-) Reviewed-by: Jason Gunthorpe Jason