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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?y86lpUbaSqoETzGW28KZT+ouZSRlra4iYbJi/ZlM+j3dbBSXyQTkjcHdegnH?= =?us-ascii?Q?RKYZhl9UFgnqPOIghniw59Oiyv/mxb8N7XmFLlBY04UjyQB7cFFDvo4q86Pi?= =?us-ascii?Q?w7WrM/e1osek8dIVgcohZ8ioTRxIxv1VM0YOPpjG5JC+MKEFDJs5a6myFK1y?= =?us-ascii?Q?tBKTAPAdPuoFL76Ko9mK2vcMajGViznm/O04b5ED65aM2QMynztBEXA4CsME?= =?us-ascii?Q?GW+ODEMVCG48HuviWYMdQI0FOD71nQ29vhbbnVjSxp6ZAY1spzi8wGhzdGB/?= =?us-ascii?Q?ECV1ORkgIVNNsJxkRUOFVKh4zOMXYDFxLA64GwPUEzGIIj7t06ROiTOhoDnt?= =?us-ascii?Q?EndJQpOffxtaAoUPF0JMsNQM927QFeBpHJN6du/EEP+kuzaOwbqX5ASfbgDD?= =?us-ascii?Q?tQVZ8jarwa1maIirh/b1pZYhj2cSJYRct/cLJ/vYp5gVU9yO+46dhiu2a6nl?= =?us-ascii?Q?EjNjg3MtFU/RtUn9ULw4JRxJEfNfhsbvOBLlQ9KW8cmZe3PrNJZWnPLR47iW?= =?us-ascii?Q?QrVT7/9pnOZddQCHFyFi7wTUlsngCRL0ML4TPhBrryeN/N3MHZoxbYSLal6i?= =?us-ascii?Q?fb2xDHUuDpboxanqZwBOV/FagTMffE4z0QOI9iygxJKSZyA2LISNBGGL+LQk?= =?us-ascii?Q?nppirRcTlADmS8+AnazpVfEkoj78/mO+DqiujJN+JizmZpv0yXY72Gm2szxV?= =?us-ascii?Q?daE3zHQKQxaKXqwHdtaSghQSITUIMk2gTqqC1tKIJBQHzA61EfclverYUjT6?= =?us-ascii?Q?GNnZgxKCO4UBFjN3lbNS832BSkI5zbc2Njv7r8nRL9S/TI0Arkpqy9zM/Sp0?= =?us-ascii?Q?AcG2limxOxBEdQsOED46S8FRr3xRfmAgQilFZzRWTEOXGP3THIpHzhzqtyOE?= =?us-ascii?Q?Rg0YTK9VwDOQxpUWtIFYvGe7DQe5KFPYo7z32xpXAkoDYYRkDsK4CdeyYuLE?= =?us-ascii?Q?BvDVCS4kdl2VRj8ncK7WW0MijJBOwMaaLDaQSni14KPPzQtAskYprnEOFuI8?= =?us-ascii?Q?75dEZCW0NdKGsOYpfXtA0JQ4NSNO6AXaygxPDKaqN6PSgts9CiE4Zj3UDIAv?= =?us-ascii?Q?MLnJYMI0f52tPyExU9U7RyF5wDd6vnu6+BWcbn/iAzoxKGi6DDoEySC1ayZf?= =?us-ascii?Q?Rmzn0Nx1DtBm9qgrM0tV3RZ5p2l3V/ycyfxw0LwtTgFg5vFeU+kKh0Jww5W4?= =?us-ascii?Q?msX4LtWSyPuLFC9nkQ06sKV5GzTU++IzyzM4oRo/uHt/fZTFNx5DvxxnOTfV?= =?us-ascii?Q?kiF4CeKjHb2iH02A0yDvlPop4tog4Lfatnvmc8sExsYv0oCjy/S/lyCK5oKo?= =?us-ascii?Q?M4ASwqrN4XnEvYIUlR1k1wqDhKCKA1baaeM6LxLPP16bo/AvOjwM33ZmXXT1?= =?us-ascii?Q?ROtB0OwsVxcwh/TY8+MqABv0mycB79SBfhFjOQB9xExfQ9yZZStxLkTXg6Qj?= =?us-ascii?Q?kMN8m4XbfHLwyCtuYFmaavhDplKHfQOrRL7wEuQFVToULr0wSa3Cux6TWbW2?= =?us-ascii?Q?PA+9NfmgwnQ+a0IcN+bAiWGpmHV2UEVTU2fXMlR7vwKyLMRA988iZKuAg2xU?= =?us-ascii?Q?1qWR9gPcB1mZgr1tPc/mebEEhEUrZNippFjgwNaZ?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: e178ebce-2b89-4136-cd4c-08db160223f6 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 24 Feb 2023 00:57:45.4211 (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: jfhPTy9YQvZsUMH+d4skycPhop1WHZKzoVNUqAI5SjiF8f6PQB+hu7O3/yDD5+P1 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB7444 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Wed, Feb 22, 2023 at 02:11:39AM +0000, Tian, Kevin wrote: > > > There was an attempt [1] to fix error unwind in iommu_attach_group(), by > > > temporarily set group->domain to NULL before calling set_domain(). > > > > > > Jason, I wonder why this recovering cannot be done in > > > __iommu_group_set_domain() directly, e.g.: > > > > > > ret = __iommu_group_for_each_dev(group, new_domain, > > > iommu_group_do_attach_device); > > > if (ret) { > > > __iommu_group_for_each_dev(group, group->domain, > > > iommu_group_do_attach_device); > > > return ret; > > > } > > > group->domain = new_domain; > > > > We talked about this already, some times this is not the correct > > recovery case, eg if we are going to a blocking domain we need to drop > > all references to the prior domain, not put them back. > > > > Failures are WARN_ON events not error recovery. > > > > OK, I remember that. Then here looks we also need temporarily > set group->domain to NULL before calling set_domain() to recover, > as [1] does. Sigh, this is too much. I made a series to clean up all the domain attach logic so the error handling is all in one place and all the same. What do you think? https://github.com/jgunthorpe/linux/commits/iommufd_hwpt Jason