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help page:  mod


NAME
  mod - module information and loading of symbols and debugging data

SYNOPSIS
  mod [ -s module [objfile] | -d module | -S | -D | -r ] 

DESCRIPTION
  With no arguments, this command displays basic information of the currently
  installed modules, consisting of the module address, name, size, and the
  object file name, if known.

  The arguments are concerned with with the loading or deleting of symbolic
  and debugging data from a module's object file:

  -s module [objfile]  Loads symbolic and debugging data from the object file
                       for the module specified.  If no objectfile argument is
                       appended, a search will be made for an object file
                       consisting of the module name with a .o suffix,
                       starting at the /lib/modules/<release> directory on
                       the host system.  If an objfile argument is appended,
                       that file will be used.
            -d module  Deletes the symbolic and debugging data of the module
                       specified.
                   -S  Load symbolic and debugging data from the object file
                       for all loaded modules.  For each module, a search
                       will be made for an object file consisting of the
                       module name with a .o suffix, starting at the
                       /lib/modules/<release> directory of the host system.
                   -D  Deletes the symbolic and debugging data of all modules.
                   -r  Reinitialize module data. All currently-loaded symbolic
                       and debugging data will be deleted, and the installed
                       module list will be updated (live system only).
 
  After symbolic and debugging data have been loaded, backtraces and text
  disassembly will be displayed appropriately.  Depending upon the processor
  architecture, data may also printed symbolically with the "p" command;
  at a minimum, the "rd" command may be used with module data symbols.
 
  If crash can recognize that the set of modules has changed while running a
  session on a live kernel, the module data will be reinitialized the next
  time this command is run; the -r option forces the reinitialization.

EXAMPLES
  Display the currently-installed modules:

    crash> mod
     MODULE   NAME         SIZE  OBJECT FILE
    c8019000  soundcore    2788  (not loaded)
    c801b000  soundlow      336  (not loaded)
    c801d000  sound       59864  (not loaded)
    c802d000  ad1848      15728  (not loaded)
    c8032000  uart401      6000  (not loaded)
    c8035000  cs4232       2472  (not loaded)
    c8043000  opl3        11048  (not loaded)
    c8047000  3c59x       18152  (not loaded)
    c804d000  sunrpc      53796  (not loaded)
    c805c000  lockd       31528  (not loaded)
    c8065000  nfsd       151896  (not loaded)
    c8092000  nfs         29752  (not loaded)
 
  Load the symbolic and debugging data of all modules:

    crash> mod -S
     MODULE   NAME         SIZE  OBJECT FILE
    c8019000  soundcore    2788  /lib/modules/2.2.5-15/misc/soundcore.o
    c801b000  soundlow      336  /lib/modules/2.2.5-15/misc/soundlow.o
    c801d000  sound       59864  /lib/modules/2.2.5-15/misc/sound.o
    c802d000  ad1848      15728  /lib/modules/2.2.5-15/misc/ad1848.o
    c8032000  uart401      6000  /lib/modules/2.2.5-15/misc/uart401.o
    c8035000  cs4232       2472  /lib/modules/2.2.5-15/misc/cs4232.o
    c8043000  opl3        11048  /lib/modules/2.2.5-15/misc/opl3.o
    c8047000  3c59x       18152  /lib/modules/2.2.5-15/net/3c59x.o
    c804d000  sunrpc      53796  /lib/modules/2.2.5-15/misc/sunrpc.o
    c805c000  lockd       31528  /lib/modules/2.2.5-15/fs/lockd.o
    c8065000  nfsd       151896  /lib/modules/2.2.5-15/fs/nfsd.o
    c8092000  nfs         29752  /lib/modules/2.2.5-15/fs/nfs.o
    
  Load the symbolic and debugging data of the soundcore module from its
  known location:
 
    crash> mod -s soundcore
     MODULE   NAME         SIZE  OBJECT FILE
    c8019000  soundcore    2788  /lib/modules/2.2.5-15/misc/soundcore.o
    
  Delete the current symbolic and debugging data of the soundcore module, 
  and then re-load it from a specified object file:
 
    crash> mod -d soundcore
    crash> mod -s soundcore /tmp/soundcore.o
     MODULE   NAME         SIZE  OBJECT FILE
    c8019000  soundcore    2788  /tmp/soundcore.o
 
  After installing a new kernel module on a live system, reinitialize the
  installed module list:

    crash> !insmod mdacon
    crash> mod
    mod: NOTE: modules have changed on this system -- reinitializing
     MODULE   NAME         SIZE  OBJECT FILE
    c8019000  soundcore    2788  (not loaded)
    c801b000  soundlow      336  (not loaded)
    c801d000  sound       59864  (not loaded)
    c802d000  ad1848      15728  (not loaded)
    c8032000  uart401      6000  (not loaded)
    c8035000  cs4232       2472  (not loaded)
    c8043000  opl3        11048  (not loaded)
    c8047000  3c59x       18152  (not loaded)
    c804d000  sunrpc      53796  (not loaded)
    c805c000  lockd       31528  (not loaded)
    c8065000  nfs         29752  (not loaded)
    c806e000  autofs       9316  (not loaded)
    c8072000  nfsd       151896  (not loaded)
    c80a1000  mdacon       3556  (not loaded)


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