I have made the following changes to the "drivers/input/mousedev.c" file: 

1. 'mousedev_write()', 'mousedev_read()':
   The changes protect an application using the 'read()' function from
   waiting indefinitely  for a disconnected mouse.  If the application
   performs a read or write  operation on the disconnected device, the
   call  fails with  the 'ENODEV'  error  code. This  behavior of  the
   'read()'   and    'write()'   functions   is    proposed   in   the
   "drivers/usb/usb-skeleton.c" file.

2. 'mousedev_poll()':
   The changes  protect an  application using the  'select()' function
   from waiting  indefinitely for a  disconnected mouse. If  the mouse
   was  disconnected, each  file descriptor  of the  respective device
   file  is  assumed  to  be  always ready  for  reading.  The  device
   disconnection is assumed to be a permanent exceptional condition on
   the  file  descriptor. The  'select()'  function  treats that  file
   descriptor as a  valid and ready one. So if  the file descriptor is
   contained in a  descriptor set supplied to a  'select()' call as an
   argument, then the 'select()' function adds that file descriptor to
   the respective  output descriptor  set, i.e., sets  the appropriate
   bit of  the respective 'fd_set'  input variable.  In this  case the
   function  returns successfully.   The mouse  disconnection  and the
   unusable  file descriptor can  be easily  detected by  checking the
   results of  the successive  'read()' calls, which  make use  of the
   results of the 'select()' call, for the 'ENODEV' error.

3. 'mousedev_disconnect()':
   a) Sending a 'SIGIO' signal.
      This   'SIGIO'  signal   protects  an   application   using  the
      'sigsuspend()' function from  waiting indefinitely for a 'SIGIO'
      signal.  If a file  descriptor corresponds  to a  device special
      file representing a mouse, and  the 'O_ASYNC' status flag is set
      on that file descriptor, a  'SIGIO' signal is generated when the
      mouse becomes disconnected.
   b) The  pointers  in  the  'mousedev_table' are  used  only by  the
      'mousedev_open()'  and  'mousedev_connect()'  functions, so  the
      'mousedev_disconnect()' function  can safely remove  the pointer
      corresponding    to   the    disconnected    mouse   from    the
      'mousedev_table'.

4. 'mousedev_free()':
   The  line "mousedev_table[mousedev->minor] =  NULL;" is  moved into
   the 'mousedev_disconnect()' function.