Documentation/filesystems/devfs/boot-options

   1 /* -*- auto-fill -*-                                                         */
   2
   3                 Device File System (devfs) Boot Options
   4
   5                 Richard Gooch <rgooch@atnf.csiro.au>
   6
   7                               18-AUG-2001
   8
   9
  10 When CONFIG_DEVFS_DEBUG is enabled, you can pass several boot options
  11 to the kernel to debug devfs. The boot options are prefixed by
  12 "devfs=", and are separated by commas. Spaces are not allowed. The
  13 syntax looks like this:
  14
  15 devfs=<option1>,<option2>,<option3>
  16
  17 and so on. For example, if you wanted to turn on debugging for module
  18 load requests and device registration, you would do:
  19
  20 devfs=dmod,dreg
  21
  22 You may prefix "no" to any option. This will invert the option.
  23
  24
  25 Debugging Options
  26 =================
  27
  28 These requires CONFIG_DEVFS_DEBUG to be enabled.
  29 Note that all debugging options have 'd' as the first character. By
  30 default all options are off. All debugging output is sent to the
  31 kernel logs. The debugging options do not take effect until the devfs
  32 version message appears (just prior to the root filesystem being
  33 mounted).
  34
  35 These are the options:
  36
  37 dmod            print module load requests to <request_module>
  38
  39 dreg            print device register requests to <devfs_register>
  40
  41 dunreg          print device unregister requests to <devfs_unregister>
  42
  43 dchange         print device change requests to <devfs_set_flags>
  44
  45 dilookup        print inode lookup requests
  46
  47 diget           print VFS inode allocations
  48
  49 diunlink        print inode unlinks
  50
  51 dichange        print inode changes
  52
  53 dimknod         print calls to mknod(2)
  54
  55 dall            some debugging turned on
  56
  57
  58 Other Options
  59 =============
  60
  61 These control the default behaviour of devfs. The options are:
  62
  63 mount           mount devfs onto /dev at boot time
  64
  65 only            disable non-devfs device nodes for devfs-capable drivers