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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?hmRBUgYhecq9X5xLwfvqCPwWaWTYjFzd+olkzko+wOyGnvY/EYMj5iUB5ZnE?= =?us-ascii?Q?5buR9EjPUz8zOX7DIiLco9F+9hkcqYV87N9+/AJhEiOC/uCIjWyJnW46FoSP?= =?us-ascii?Q?STk3rVESEeTKaG/UBBANTWcKygqhA7eD+GY4+Y9ShlA7inIkYv3n2lSIf276?= =?us-ascii?Q?cZLmCwIHiAQ+kJOBN1EedQ5bmnZLB3FKcWlO1mHCX622pwvdkqpV75ogOs+T?= =?us-ascii?Q?hTmADGHaPTqkd65KjL4qmihJAeG+n2zFhsB5k/xq8EpncOFWM5MnI5UD9ojy?= =?us-ascii?Q?6lTMRLfvbyaNqUPr2ZrSrK5PHlWqS4bWq+YqBGMMt/R65Qi2qld4MO/Px+XT?= =?us-ascii?Q?N31+DTbObqAKkMvhxJavm1mWUxRRCWWnPPb3hmNuQv2v4lRKS/3OuVmTtUzi?= =?us-ascii?Q?KeICoZqOKi74WdbYAtuu4sESh733fWxD5z7/mXTNEZ7I7Y3ozaA08mGLzbUX?= =?us-ascii?Q?tnPxUhXr0JCef2dr/xN7EAzpzXwvsC+2eaX08Hm2ucpgB2oUF+xnmJWOpPay?= =?us-ascii?Q?dogKVwodECCb841yzzdbD08gQ6PCcA7lgg1+aTlJxBllOvGrVHrpQFSPWIQ7?= =?us-ascii?Q?d9thPmVi1zPyqlqNhOFU9JK5JJhyJEO8Vat5kvkxC9VSeyjzyn00igdjOjti?= =?us-ascii?Q?Oj9KL0jIecqzFUsB2/whcI7sMc+kIYyBNs3gvR4KbmT8BUd9wm7Nmw0ohf7+?= =?us-ascii?Q?SSU4wc5wHuKfYnS1VBvnXZtkCgYc0iht+BupyXIIJvvedvHU7ZWzjFoZ5ccg?= =?us-ascii?Q?Z1ZxPWP2PqkmP/wPXQvTRwywM8gcy2uiaAN9DADToYTK+tcSjA9cco79ZEkC?= =?us-ascii?Q?rXCuUNhgXQxUPhS733NEVNNzh13SR0UtbLPxRvfQqd+JHVFDa6Ri8ydlytd0?= =?us-ascii?Q?1ssG4YTS4765IzcbaOmvdGXrR0fIhNY+KqNVUB3SPJeEOG0MFt20t3XKmhcf?= =?us-ascii?Q?CkiuBJF2QHUyBYhHaNz8VVaI4vjKOJohpBaVLzE6vD12OoavBjrdalPmOoOl?= =?us-ascii?Q?G0wR9TYUuye/2xsS2Ka3eAgiGRCcGgC0bzrO5CetbauEywJ5c/OE3fd//EDK?= =?us-ascii?Q?J4mNcnL+/tL45zYBjnQNmiltxhEyN11XuS0Y+iF4gvnhxK5exaY3cIHCPQQZ?= =?us-ascii?Q?opa1eGkFTloZw7bPaGCbEK7UETuVyMpNUuwGMb/VgHNYVT4Kt6tB3qIqMq8T?= =?us-ascii?Q?SaeuLEzvwPYQMFs4STPijjcQ8NFSgsggba2etL6JuzaLiOuUIzkHtk3defv3?= =?us-ascii?Q?ggKDLg3dxGg7LfedCewGj0nJSGHm/2VyxYVCyG4b2i5+6Fa6cDNcWH/d+TKh?= =?us-ascii?Q?lBvXe+EHTA4GvIfEvBYqCkpxels449kNZ66SCAaBxLl0Y/0nl2jtiyA6KmGS?= =?us-ascii?Q?PLGfCwcYH8tXXs/MuhCU1LNHEFnAUokj2rSDbznwJnSZ1X38BFFwaftD07qQ?= =?us-ascii?Q?MA5R+MrFAoWpVZgjq0vzEk9Ze9TxNzITmbcop0KiIMGxxVAYeU/bJj0cdeU3?= =?us-ascii?Q?ndwFUxjxCCIB1A8EDB7b/uL+WrLfodlgZKVxwNgFjzsJZtbTo+aKDw5fCT68?= =?us-ascii?Q?JNU7Pi4Y5PbudSxSqUjoWcDel2TAj1rf6NC7PYEd?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: eb61087c-2441-4431-0db6-08db89e241f3 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Jul 2023 12:01:46.6970 (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: 8mhGHkFxzoXXsIif/hQU4aWPjfqM5vQ+Sm8uwnpon6bYK9by/zoVAJc3+cOs1QWL X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN2PR12MB4455 On Fri, Jul 21, 2023 at 07:10:57AM +0000, Tian, Kevin wrote: > > From: Jason Gunthorpe > > Sent: Wednesday, July 19, 2023 3:06 AM > > > > int iommu_device_use_default_domain(struct device *dev) > > { > > - struct iommu_group *group = iommu_group_get(dev); > > + /* Caller must be a probed driver on dev */ > > + struct iommu_group *group = dev->iommu_group; > > int ret = 0; > > this is called in the probing path by .dma_configure(). > > the driver hasn't been probed yet hence the rationale to not > refcount is due to device_lock() instead? At this point the driver core has partially attached/detached a driver so I'm considering it part of the probed driver explanation. Really during anything protected by the driver core probe path is assured that the group cannot change. Jason