tree: git://linuxtv.org/sailus/media_tree.git media-ref head: 9587641ab37e563866fb73acc04735eccd59a2d3 commit: 2afdf22741b499ad0c798c891fab451a8da50ce0 [65/67] media: mc: Implement best effort media device removal safety sans refcount reproduce: (https://download.01.org/0day-ci/archive/20231222/202312220658.R4fi66yq-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202312220658.R4fi66yq-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> ./include/media/media-devnode.h:54: warning: Function parameter or member 'release' not described in 'media_file_operations' >> ./include/media/media-devnode.h:99: warning: Function parameter or member 'mcdev' not described in 'media_devnode_compat_ref' >> ./include/media/media-devnode.h:155: warning: Function parameter or member 'mcdev' not described in 'media_devnode' vim +54 ./include/media/media-devnode.h cf4b9211b5680c Laurent Pinchart 2009-12-09 32 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 33 /** 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 34 * struct media_file_operations - Media device file operations 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 35 * 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 36 * @owner: should be filled with %THIS_MODULE 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 37 * @read: pointer to the function that implements read() syscall 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 38 * @write: pointer to the function that implements write() syscall 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 39 * @poll: pointer to the function that implements poll() syscall 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 40 * @ioctl: pointer to the function that implements ioctl() syscall 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 41 * @compat_ioctl: pointer to the function that will handle 32 bits userspace f040e0fd29e4a0 Randy Dunlap 2020-07-15 42 * calls to the ioctl() syscall on a Kernel compiled with 64 bits. 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 43 * @open: pointer to the function that implements open() syscall 2afdf22741b499 Sakari Ailus 2023-01-31 44 o */ cf4b9211b5680c Laurent Pinchart 2009-12-09 45 struct media_file_operations { cf4b9211b5680c Laurent Pinchart 2009-12-09 46 struct module *owner; cf4b9211b5680c Laurent Pinchart 2009-12-09 47 ssize_t (*read) (struct file *, char __user *, size_t, loff_t *); cf4b9211b5680c Laurent Pinchart 2009-12-09 48 ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *); a3f8683bf7d5e6 Al Viro 2017-07-02 49 __poll_t (*poll) (struct file *, struct poll_table_struct *); cf4b9211b5680c Laurent Pinchart 2009-12-09 50 long (*ioctl) (struct file *, unsigned int, unsigned long); c6c1d50b51e76b Sakari Ailus 2013-01-22 51 long (*compat_ioctl) (struct file *, unsigned int, unsigned long); 2cd8dbb38fcc12 Sakari Ailus 2023-01-31 52 int (*open) (struct media_devnode *, struct file *); cf4b9211b5680c Laurent Pinchart 2009-12-09 53 int (*release) (struct file *); cf4b9211b5680c Laurent Pinchart 2009-12-09 @54 }; cf4b9211b5680c Laurent Pinchart 2009-12-09 55 2afdf22741b499 Sakari Ailus 2023-01-31 56 /** 2afdf22741b499 Sakari Ailus 2023-01-31 57 * struct media_devnode_cdev - Workaround for drivers not managing media device 2afdf22741b499 Sakari Ailus 2023-01-31 58 * lifetime - character device 2afdf22741b499 Sakari Ailus 2023-01-31 59 * 2afdf22741b499 Sakari Ailus 2023-01-31 60 * Store the characeter device and whether this is a compatibility reference or 2afdf22741b499 Sakari Ailus 2023-01-31 61 * not. struct media_devnode_cdev is embedded in either struct 2afdf22741b499 Sakari Ailus 2023-01-31 62 * media_devnode_compat_ref or struct media_devnode. 2afdf22741b499 Sakari Ailus 2023-01-31 63 * 2afdf22741b499 Sakari Ailus 2023-01-31 64 * @cdev: the chracter device 2afdf22741b499 Sakari Ailus 2023-01-31 65 * @is_compat_ref: Is this a compatibility reference or not? 2afdf22741b499 Sakari Ailus 2023-01-31 66 */ 2afdf22741b499 Sakari Ailus 2023-01-31 67 struct media_devnode_cdev { 2afdf22741b499 Sakari Ailus 2023-01-31 68 struct cdev cdev; 2afdf22741b499 Sakari Ailus 2023-01-31 69 bool is_compat_ref; 2afdf22741b499 Sakari Ailus 2023-01-31 70 }; 2afdf22741b499 Sakari Ailus 2023-01-31 71 2afdf22741b499 Sakari Ailus 2023-01-31 72 /** 2afdf22741b499 Sakari Ailus 2023-01-31 73 * struct media_devnode_compat_ref - Workaround for drivers not managing media 2afdf22741b499 Sakari Ailus 2023-01-31 74 * device lifetime - reference 2afdf22741b499 Sakari Ailus 2023-01-31 75 * 2afdf22741b499 Sakari Ailus 2023-01-31 76 * The purpose if this struct is to support drivers that do not manage the 2afdf22741b499 Sakari Ailus 2023-01-31 77 * lifetime of their respective media devices to avoid the worst effects of 2afdf22741b499 Sakari Ailus 2023-01-31 78 * this, namely an IOCTL call on an open file handle to a device that has been 2afdf22741b499 Sakari Ailus 2023-01-31 79 * unbound causing a kernel oops systematically. This is not a fix. The proper, 2afdf22741b499 Sakari Ailus 2023-01-31 80 * reliable way to handle this is to manage the resources used by the 2afdf22741b499 Sakari Ailus 2023-01-31 81 * driver. This struct and its use can be removed once all drivers have been 2afdf22741b499 Sakari Ailus 2023-01-31 82 * converted. 2afdf22741b499 Sakari Ailus 2023-01-31 83 * 2afdf22741b499 Sakari Ailus 2023-01-31 84 * @dev: struct device that remains in place as long as any reference remains 2afdf22741b499 Sakari Ailus 2023-01-31 85 * @cdev: the related character device 2afdf22741b499 Sakari Ailus 2023-01-31 86 * @devnode: a pointer back to the devnode 2afdf22741b499 Sakari Ailus 2023-01-31 87 * @release: pointer to the function that will release the resources 2afdf22741b499 Sakari Ailus 2023-01-31 88 * allocated by the @open function. 2afdf22741b499 Sakari Ailus 2023-01-31 89 * @registered: is this device registered? 2afdf22741b499 Sakari Ailus 2023-01-31 90 * @minor: the minor number of the media devnode 2afdf22741b499 Sakari Ailus 2023-01-31 91 */ 2afdf22741b499 Sakari Ailus 2023-01-31 92 struct media_devnode_compat_ref { 2afdf22741b499 Sakari Ailus 2023-01-31 93 struct device dev; 2afdf22741b499 Sakari Ailus 2023-01-31 94 struct media_devnode_cdev mcdev; 2afdf22741b499 Sakari Ailus 2023-01-31 95 struct media_devnode *devnode; 2afdf22741b499 Sakari Ailus 2023-01-31 96 int (*release)(struct file *); 2afdf22741b499 Sakari Ailus 2023-01-31 97 atomic_t registered; 2afdf22741b499 Sakari Ailus 2023-01-31 98 unsigned int minor; 2afdf22741b499 Sakari Ailus 2023-01-31 @99 }; 2afdf22741b499 Sakari Ailus 2023-01-31 100 d1678fa08df53e Laurent Pinchart 2015-11-03 101 /** d1678fa08df53e Laurent Pinchart 2015-11-03 102 * struct media_devnode_fh - Media device node file handle d1678fa08df53e Laurent Pinchart 2015-11-03 103 * @devnode: pointer to the media device node 2afdf22741b499 Sakari Ailus 2023-01-31 104 * @ref: media device compat ref, if the driver does not manage media 2afdf22741b499 Sakari Ailus 2023-01-31 105 * device lifetime d1678fa08df53e Laurent Pinchart 2015-11-03 106 * d1678fa08df53e Laurent Pinchart 2015-11-03 107 * This structure serves as a base for per-file-handle data storage. Media d1678fa08df53e Laurent Pinchart 2015-11-03 108 * device node users embed media_devnode_fh in their custom file handle data d1678fa08df53e Laurent Pinchart 2015-11-03 109 * structures and store the media_devnode_fh in the file private_data in order d1678fa08df53e Laurent Pinchart 2015-11-03 110 * to let the media device node core locate the media_devnode corresponding to a d1678fa08df53e Laurent Pinchart 2015-11-03 111 * file handle. d1678fa08df53e Laurent Pinchart 2015-11-03 112 */ d1678fa08df53e Laurent Pinchart 2015-11-03 113 struct media_devnode_fh { d1678fa08df53e Laurent Pinchart 2015-11-03 114 struct media_devnode *devnode; 2afdf22741b499 Sakari Ailus 2023-01-31 115 struct media_devnode_compat_ref *ref; d1678fa08df53e Laurent Pinchart 2015-11-03 116 }; d1678fa08df53e Laurent Pinchart 2015-11-03 117 cf4b9211b5680c Laurent Pinchart 2009-12-09 118 /** cf4b9211b5680c Laurent Pinchart 2009-12-09 119 * struct media_devnode - Media device node 0db5c79989de2c Mauro Carvalho Chehab 2016-06-16 120 * @media_dev: pointer to struct &media_device 75c7e295707e7a Mauro Carvalho Chehab 2015-12-13 121 * @fops: pointer to struct &media_file_operations with media device ops 0db5c79989de2c Mauro Carvalho Chehab 2016-06-16 122 * @dev: pointer to struct &device containing the media controller device ec0255cad2dace Mauro Carvalho Chehab 2015-08-22 123 * @cdev: struct cdev pointer character device cf4b9211b5680c Laurent Pinchart 2009-12-09 124 * @parent: parent device 455a5d54c7d19b Sakari Ailus 2023-12-15 125 * @minor: device node minor number, -1 if unassigned 48a7c4bac94dfb Mauro Carvalho Chehab 2016-08-29 126 * @flags: flags, combination of the ``MEDIA_FLAG_*`` constants 82631b5bb268f6 Mauro Carvalho Chehab 2016-09-08 127 * @release: release callback called at the end of ``media_devnode_release()`` 82631b5bb268f6 Mauro Carvalho Chehab 2016-09-08 128 * routine at media-device.c. 2afdf22741b499 Sakari Ailus 2023-01-31 129 * @ref: reference for providing best effort memory safety in device 2afdf22741b499 Sakari Ailus 2023-01-31 130 * removal cf4b9211b5680c Laurent Pinchart 2009-12-09 131 * cf4b9211b5680c Laurent Pinchart 2009-12-09 132 * This structure represents a media-related device node. cf4b9211b5680c Laurent Pinchart 2009-12-09 133 * cf4b9211b5680c Laurent Pinchart 2009-12-09 134 * The @parent is a physical device. It must be set by core or device drivers cf4b9211b5680c Laurent Pinchart 2009-12-09 135 * before registering the node. cf4b9211b5680c Laurent Pinchart 2009-12-09 136 */ cf4b9211b5680c Laurent Pinchart 2009-12-09 137 struct media_devnode { cf4b9211b5680c Laurent Pinchart 2009-12-09 138 /* device ops */ cf4b9211b5680c Laurent Pinchart 2009-12-09 139 const struct media_file_operations *fops; cf4b9211b5680c Laurent Pinchart 2009-12-09 140 cf4b9211b5680c Laurent Pinchart 2009-12-09 141 /* sysfs */ cf4b9211b5680c Laurent Pinchart 2009-12-09 142 struct device dev; /* media device */ 2afdf22741b499 Sakari Ailus 2023-01-31 143 struct media_devnode_cdev mcdev; /* character device + compat status */ cf4b9211b5680c Laurent Pinchart 2009-12-09 144 struct device *parent; /* device parent */ cf4b9211b5680c Laurent Pinchart 2009-12-09 145 cf4b9211b5680c Laurent Pinchart 2009-12-09 146 /* device info */ cf4b9211b5680c Laurent Pinchart 2009-12-09 147 int minor; cf4b9211b5680c Laurent Pinchart 2009-12-09 148 unsigned long flags; /* Use bitops to access flags */ cf4b9211b5680c Laurent Pinchart 2009-12-09 149 cf4b9211b5680c Laurent Pinchart 2009-12-09 150 /* callbacks */ 163f1e93e99504 Mauro Carvalho Chehab 2016-03-23 151 void (*release)(struct media_devnode *devnode); 2afdf22741b499 Sakari Ailus 2023-01-31 152 2afdf22741b499 Sakari Ailus 2023-01-31 153 /* compat reference */ 2afdf22741b499 Sakari Ailus 2023-01-31 154 struct media_devnode_compat_ref *ref; cf4b9211b5680c Laurent Pinchart 2009-12-09 @155 }; cf4b9211b5680c Laurent Pinchart 2009-12-09 156 :::::: The code at line 54 was first introduced by commit :::::: cf4b9211b5680cd9ca004232e517fb7ec5bf5316 [media] media: Media device node support :::::: TO: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> :::::: CC: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
