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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?rZ2ODPoIfSDYEyXCO2pV5XpmVKH9DW+BXmSkyZWdsrNtJjHznmdkrxOgsWQB?= =?us-ascii?Q?qlby0whxrrE3HUiUhPrCgLYRj6Tx9Iw+TqlpEl2SQfAZ2oRFjQ6J46e248Np?= =?us-ascii?Q?R+QaUFX10qvufv7372wiNKGphnuDtBXEzjl3BhdyRwN0sFLyagSd+iLmwc/Y?= =?us-ascii?Q?h8lrezG8ZKZR1pfutDVY344q6GSz8k8CjfFOrUWtwp2/v+58qPwMlv1wfIxA?= =?us-ascii?Q?u8TZnvKoIyRwg6q8XaKPDzGtZjLvD0dqbvWm6YlJFrV1dhxkS6fEsikWwoaW?= =?us-ascii?Q?Km3Y1oGFq6aM1b8Zi/vY3pWMPNewEztt82xZzLO8YzIN8LNt5Nmkz0K3bIn+?= =?us-ascii?Q?cotAGEk9DLo/UCjCS3ieNca6gRpqN2xcQL0A+xHJQVv/POmdycwWM5l8PrP1?= =?us-ascii?Q?EnFts9XahKdOl1gA2StwAj7pRszpl1K+ps6ur+WBKAGQ+Qx5c3ttkVUd21Yt?= =?us-ascii?Q?ybnK2o/TUNtB1A0+nNIVk4WX9M1WGw6spo+Q8cPlAzikJsMn88SRZl/nY+Rz?= =?us-ascii?Q?/7KxNUVks6WrabOnlGHxiEk+Xib5HYE4HLU9TUyfiChUwX6N5gA3IjdPLMwU?= =?us-ascii?Q?tZPFMSSvaJKtm9OLoGZUH8SzLu9AYiAZ8YZq+lJ2cp3b42Q4uFlUXiGsru6G?= =?us-ascii?Q?Um89j0Aj2xKNXgTkMOQWhW/3sJr8s/pXgTJf8M8eWTtVZ1+pfIdE+aa/NEQf?= =?us-ascii?Q?PrpvLPGfsNqZ8r5yfDk77+tWgQaU1zAQdSuIVBuqsQhHYZPggSsLtl5Zj5vZ?= =?us-ascii?Q?F9B6CdNmTfHXS+yFmHZDCkA1BSc3MyYwBwhVb1OaLrk9WLsmfd5G7g/NwsFy?= =?us-ascii?Q?VzDjbe0q/GeoHx/nfQ58M9QSDqL7mk16doiS321v5eadzMKOK04rqytOwypZ?= =?us-ascii?Q?Jf8239sVkTSXo40gYsclwws+tZdt1l9fOEiU9UkM8UPMK4rxLXfe48/JjeK2?= =?us-ascii?Q?2l3JNMv+elXWE7KgwvXDNOzWTCpdOQqTxgXCyDZpZh666SvsJ1xqc2ASIdV2?= =?us-ascii?Q?1Q/tON1VaoEtG3/DNvqPLy+llSssnXGv9Eot4gZzd8t+z4DeiNcHOs8apca7?= =?us-ascii?Q?WC3to334xU+1alwqC5f6ta0Ng9z7LL1B2J7dy9AT+CFfQ997kelIgaME/Vp9?= =?us-ascii?Q?jk/QKpituoWmCp4u8yES4Kvg1mi96+0viRnBlPLj5q+zPzguYAVFw6Qx/6Om?= =?us-ascii?Q?/31YVrOis7I6ib/2ztZTexUmHp5I7a8w7XnAYPPzVObvPYeV/n51X4CtY1fO?= =?us-ascii?Q?2g/kgxNv3NyKMX6VEnIXH+an7z0RZcwhUyUWZ5NjNIak3TnH4lvdxo2/Wafi?= =?us-ascii?Q?N2R5OdoNdGp6CgSv7Irorfeh?= X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: cb4ce8bc-5ab6-4883-49f3-08d94371ab90 X-MS-Exchange-CrossTenant-AuthSource: MWHPR1001MB2365.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Jul 2021 07:09:35.0944 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: qD/SKw1q4Ad09fSpKSfxEwWNdeR6wSKgSjUkuFfJiTYoEKOsTNzxd+7VBBVPLnv4J/p+W0CyUmXAPe8k0BepAlDmtpDEQuLodk945lN5z1k= X-MS-Exchange-Transport-CrossTenantHeadersStamped: MWHPR10MB1999 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=10040 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 malwarescore=0 mlxscore=0 suspectscore=0 phishscore=0 adultscore=0 mlxlogscore=999 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2107100024 X-Proofpoint-GUID: 9IEFBrcQy8h5OJfvyuh8PKVNDyKYZk80 X-Proofpoint-ORIG-GUID: 9IEFBrcQy8h5OJfvyuh8PKVNDyKYZk80 The other thing which is quite tricky to get right is kobj releases. I have a bunch of these static checker warning but they're annoying because they're not something which really affects real life so I can't be bothered to fix or report them. Also some of them are just unfixable, for example __video_register_device(). drivers/media/v4l2-core/v4l2-dev.c 1031 /* Part 4: register the device with sysfs */ 1032 vdev->dev.class = &video_class; 1033 vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); 1034 vdev->dev.parent = vdev->dev_parent; 1035 dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num); 1036 ret = device_register(&vdev->dev); If device_register() fails then it's illegal to manually clean up. 1037 if (ret < 0) { 1038 pr_err("%s: device_register failed\n", __func__); 1039 goto cleanup; ^^^^^^^^^^^^^ But this does, but it turns out it's fine. 1040 } 1041 /* Register the release callback that will be called when the last 1042 reference to the device goes away. */ 1043 vdev->dev.release = v4l2_device_release; The ->release() function is not set until here so it's just going to trigger the debug message in kobject_cleanup() about a missing ->release() function. So no problems. 1044 1045 if (nr != -1 && nr != vdev->num && warn_if_nr_in_use) 1046 pr_warn("%s: requested %s%d, got %s\n", __func__, 1047 name_base, nr, video_device_node_name(vdev)); 1048 1049 /* Increase v4l2_device refcount */ 1050 v4l2_device_get(vdev->v4l2_dev); 1051 1052 /* Part 5: Register the entity. */ 1053 ret = video_register_media_controller(vdev); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ But then there is no way to clean up from this is video_register_media_controller() fails. If we call put_device() it would lead to use after frees in the callers. We just have to ignore the error. It's a minor thing, but it's so frustrating. 1054 1055 /* Part 6: Activate this minor. The char device can now be used. */ 1056 set_bit(V4L2_FL_REGISTERED, &vdev->flags); 1057 1058 return 0; regards, dan carpenter