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X-MS-Exchange-AntiSpam-MessageData: =?us-ascii?Q?4bp0QfL/lb36WQWXanld8C+CCrmcy2J8mq2gNMs7D57ox0vjn5F48fHVJ6hz?= =?us-ascii?Q?NeFYXzOi0+sMs8bd/sbNU4mUzaJrMrB8yuRwyRUfKfndDCsLYVS7CT9Tg1AE?= =?us-ascii?Q?temSLroEpQzmiJx7fCnCbHAJmVuYVGKkI/OPSuywfnaxuC/ClH1BCoIVy1zd?= =?us-ascii?Q?gqYnA9fU/TtcPr3xnQhi7r2sW1n2xgmwmKqj2YYNAXoIf9kWGiidyu9/DpKu?= =?us-ascii?Q?JKWmKFJMRaPKQQxh3ztCuUjboLj+J66gX9Ii0XOv/J2Uc238x6PBrF425fpv?= =?us-ascii?Q?6Yp6QVBxU8sye2IH//a8ns3VqokUmxKUtXy+USL7Lt/kX9dXQ5Yxwe8hfgjx?= =?us-ascii?Q?kVxxQklln6ypaL8rjzvsm6hQ/9Qyvf6YKi/dmFYovvnPHIuD4UmaG0w0dBG0?= =?us-ascii?Q?bvGv+QwoC5qqSO2uWgiSpfGxCDMyIcUpa3V/KKPjjtlY1CGT4UGLOh7cV5yv?= =?us-ascii?Q?B8LMgZHpXNSOdsjl7VsrokpxtIzjA5K14aCWYZqGwfNkvxcObYR7VLUkwykN?= =?us-ascii?Q?zwDn5DbpFwXEisbsWDqhzDw9Kf41Pa+GYch17ewzL4mihUypBfZBRJHR9hW3?= =?us-ascii?Q?MTh/s7+m/w/eAnUFv4lmxiYSlf+aMecsJuGKhr+Oc+NBV4wSysXDWbUOWyaA?= =?us-ascii?Q?92IuXgQWMMDCdXVydfv2frlBK9t+X7PXr3ljolKEn2E/MujBMp5aiM50RmfS?= =?us-ascii?Q?Jc7wo6RWgTb2VxyeCHW3XH4LwfYbWxr1KYLdhzn/evfoK/gFYAdcY40MlzQC?= =?us-ascii?Q?K1RGo5qaaLABNteyDo3tXhENI2uFEqeEjQrxYuYNyopxOLRW3Pgcp2HYegTI?= =?us-ascii?Q?PmR3IzvwJqTTV3fAGtHuidI3DQkP9aN+YUfO8s+KvI2hTBS+GtttMyFqc65z?= =?us-ascii?Q?bpevDxgNBH1sLRXaLxhr4qbDv3cWvL0ZYV7vdjnIa5RjptuUmSNQ2q1cKBcE?= =?us-ascii?Q?f/QByig1KkBw/bHCVBze8APY35NaFtkhb6ilMaOuyYyioQW9hdvhtiuunFSJ?= =?us-ascii?Q?9Y5HAwwx/20QUwOGCk2zRT/0IQ22FibzChYB60IL3w75Gv2YWz0jrQWFCMbI?= =?us-ascii?Q?/0R98F9nujxA1SSb5xQpKzFH8jKg6yV/JCBi6c3uWomX5FpydBAXDW2wZbuS?= =?us-ascii?Q?OaPLJ2CpF09MC8JzgAguwg3R4e9RuoKlvho3m8/KPMtC66JlT/Y32454cD53?= =?us-ascii?Q?CuAYp2D5RSk5VhisgDvMtd0r/8EfGB3A1+dQ8G+CKRbLZlE5cTwIjnu5Nx2r?= =?us-ascii?Q?Zym5QT1uJp6TxZEWY9vj+8TePQ+/rwf3I/KKDEtZpACwOijIdJ95UOOSDenV?= =?us-ascii?Q?d2KwqHma4du/johR5RtU/Oz8Se9kdpq07h417YPwkW7oqA=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 264b1128-3180-4d5d-ad4f-08d8e8d075c5 X-MS-Exchange-CrossTenant-AuthSource: DM6PR12MB3834.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Mar 2021 23:08:50.3074 (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: ZqW6gG82T5mDSvLdRJoz4YRB02Ox5Ui/tUwj8WVFlmAzyVExwV8A4QnAMYolnlR3 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4944 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Tue, Mar 16, 2021 at 02:24:54PM -0600, Alex Williamson wrote: > > > @@ -935,32 +916,18 @@ void *vfio_del_group_dev(struct device *dev) > > > WARN_ON(!unbound); > > > > > > vfio_device_put(device); > > > - > > > - /* > > > - * If the device is still present in the group after the above > > > - * 'put', then it is in use and we need to request it from the > > > - * bus driver. The driver may in turn need to request the > > > - * device from the user. We send the request on an arbitrary > > > - * interval with counter to allow the driver to take escalating > > > - * measures to release the device if it has the ability to do so. > > > - */ > > > > Above comment still makes sense even with this patch. What about > > keeping it? otherwise: > > The comment is not exactly correct after this code change either, the > device will always be present in the group after this 'put'. Instead, > the completion now indicates the reference count has reached zero. If > it's worthwhile to keep more context to the request callback, perhaps: > > /* > * If there are still outstanding device references, such as > * from the device being in use, periodically kick the optional > * device request callback while waiting. > */ > > It's also a little obvious that's what we're doing here even without > the comment. Thanks, Indeed, that is the explanation why I dropped it. Thanks, Jason