MODPROBE(8)						       Linux Module Support						       MODPROBE(8)

NAME

       modprobe - high level handling of loadable modules

SYNOPSIS

       modprobe [-adnqv] [-C config] module [symbol=value ...]
       modprobe [-adnqv] [-C config] [-t type] pattern
       modprobe -l [-C config] [-t type] pattern
       modprobe -c [-C config]
       modprobe -r [-dnv] [-C config] [module ...]
       modprobe -Vh

OPTIONS

       -a, --all
	      Load all matching modules instead of stopping after the first successful loading.

       -c, --showconfig
	      Show the currently used configuration.

       -C, --config config
	      Use  the	file config instead of (the optional) /etc/modules.conf to specify the configuration.  The environment variable MODULECONF
	      can also be used to select (and override) a different configuration file from the default  /etc/modules.conf  (or  /etc/conf.modules
	      (deprecated)).

       When environment variable UNAME_MACHINE is set, modutils will use its value instead of the machine field from the uname() syscall.  This is
       mainly of use when you are compiling 64 bit modules in 32 bit user space or vice versa, set UNAME_MACHINE  to  the  type  of  the  modules.
       Current	modutils  does not support full cross build mode for modules, it is limited to choosing between 32 and 64 bit versions of the host
       architecture.

       -d, --debug
	      Show information about the internal representation of the stack of modules.

       -h, --help
	      Display a summary of options and immediately exit.

       -k, --autoclean
	      Set 'autoclean' on loaded modules.  Used by the kernel when it calls on modprobe	to  satisfy  a	missing  feature  (supplied  as  a
	      module).	The -q option is implied by -k.  These options will automatically be sent to insmod.

       -l, --list
	      List matching modules.

       -n, --show
	      Don't actually perform the action, just show what would be done.

       -q, --quiet
	      Do  not  complain about insmod failing to install a module.  Continue as normal, but silently, with other possibilities for modprobe
	      to test.	This option will automatically be sent to insmod.

       -r, --remove
	      Remove module (stacks) or do autoclean, depending on whether there are any modules mentioned on the command line.

       -s, --syslog
	      Report via syslog instead of stderr.  This options will automatically be sent to insmod.

       -t moduletype; --type moduletype
	      Only consider modules of this type.  modprobe will only look at  modules	whose  directory  path	includes  exactly  "/moduletype/".
	      moduletype  can  include	more  than  one  directory  name,  e.g.  "-t drivers/net"  would  list modules in xxx/drivers/net/ and its
	      subdirectories.

       -v, --verbose
	      Print all commands as they are executed.

       -V, --version
	      Display the version of modprobe.

       Note:  Module names must not contain paths (no '/'), nor may they contain the trailing '.o'.  For example, slip is a valid module name  for
	      modprobe, /lib/modules/2.2.19/net/slip and slip.o are invalid.  This applies to the command line and to entries in the config.

DESCRIPTION

       The  modprobe  and  depmod  utilities  are  intended  to  make  a  Linux  modular  kernel more manageable for all users, administrators and
       distribution maintainers.

       Modprobe uses a "Makefile"-like dependency file, created by depmod, to automatically load the relevant module(s) from the  set  of  modules
       available in predefined directory trees.

       Modprobe is used to load a single module, a stack of dependent modules, or all modules that are marked with a specified tag.

       Modprobe  will  automatically  load  all  base  modules	needed in a module stack, as described by the dependency file modules.dep.  If the
       loading of one of these modules fails, the whole current stack of modules loaded in the current session will be unloaded automatically.

       Modprobe has two ways of loading modules. One way (the probe mode) will try to load a module out of a list (defined by pattern).   Modprobe
       stops loading as soon as one module loads successfully.	This could be used to autoload one Ethernet driver out of a list.
       The other way modprobe can be used is to load all modules from a list.  See EXAMPLES, below.

       With  the  option  -r,  modprobe  will  automatically  unload  a stack of modules, similar to the way "rmmod -r" does. Note that using just
       "modprobe -r" will clean up unused autoloaded modules and also perform  the  pre-  and  post-remove  commands  in  the  configuration  file
       /etc/modules.conf.

       The combining the options -l and -t lists all available modules of a certain type.

       Option -c will print the currently used configuration (default + configuration file).

CONFIGURATION

       The behavior of modprobe (and depmod) can be modified by the (optional) configuration file /etc/modules.conf.
       For  a  more  detailed  description  of	what  this file can contain, as well as the default configuration used by depmod and modprobe, see
       modules.conf(5).

       Note that the pre- and post-remove commands will not be executed if a module is "autocleaned" by kerneld!  Look for the	up-coming  support
       for persistent module storage instead.
       If  you	want to use the pre- and post-install features, you will have to turn off autoclean for kerneld and instead put something like the
       following line in your crontab (this is used for kmod systems as well) to do autoclean every 2 minutes:
	*/2 * * * * test -f /proc/modules && /sbin/modprobe -r

STRATEGY

       The idea is that modprobe will look first in the directory containing modules compiled for the current  release	of  the  kernel.   If  the
       module is not found there, modprobe will look in the directory common to the kernel version (e.g. 2.0, 2.2).  If the module is still found,
       modprobe will look in the directory containing modules for a default release, and so on.

       When you install a new linux, the modules should be moved to a directory related to the	release  (and  version)  of  the  kernel  you  are
       installing.  Then you should do a symlink from this directory to the "default" directory.

       Each time you compile a new kernel, the command "make modules_install" will create a new directory, but won't change the "default" link.

       When  you  get  a  module  unrelated  to  the  kernel  distribution you should place it in one of the version-independent directories under
       /lib/modules.

       This is the default strategy, which can be overridden in /etc/modules.conf.

EXAMPLES

       modprobe -t net
	      Load one of the modules that are stored in the directory tagged "net".  Each module are tried until one succeeds.

       modprobe -a -t boot
	      All modules that are stored in directories tagged "boot" will be loaded.

       modprobe slip
	      This will attempt to load the module slhc.o if it was not previously loaded, since the slip module needs the  functionality  in  the
	      slhc module.  This dependency will be described in the file modules.dep that was created automatically by depmod.

       modprobe -r slip
	      This will unload the slip module.  It will also unload the slhc module automatically, unless it is used by some other module as well
	      (e.g. ppp).

FILES

       /etc/modules.conf (alternatively but deprecated /etc/conf.modules)
       /lib/modules/*/modules.dep,
       /lib/modules/*

SEE ALSO

       depmod(8), lsmod(8), kerneld(8), ksyms(8), rmmod(8).

SAFE MODE

       If the effective uid is not equal to the real uid then modprobe treats its input with extreme suspicion.   The  last  parameter	is  always
       treated	as  a  module  name,  even  if it starts with '-'.  There can only be one module name and options of the form "variable=value" are
       forbidden.  The module name is always treated as a string, no meta expansion is performed in safe mode.	However meta  expansion  is  still
       applied to data read from the config file.

       euid  may  not  be  equal  to  uid  when modprobe is invoked from the kernel, this is true for kernels >= 2.4.0-test11.	In an ideal world,
       modprobe could trust the kernel to only pass valid parameters to modprobe.  However at least one local root exploit  has  occurred  because
       high level kernel code passed unverified parameters direct from the user to modprobe.  So modprobe no longer trusts kernel input.

       modprobe automatically sets safe mode when the environment consists only of these strings
	HOME=/
	TERM=linux
	PATH=/sbin:/usr/sbin:/bin:/usr/bin
       This  detects  modprobe	execution  from  the  kernel on kernels 2.2 though 2.4.0-test11, even if uid == euid, which it does on the earlier
       kernels.

LOGGING COMMANDS

       If directory /var/log/ksymoops exists and modprobe is run with an option that could load or a delete a module then modprobe  will  log  its
       command	and  return  status  in /var/log/ksymoops/`date +%Y%m%d.log`.  There is no switch to disable this automatic logging, if you do not
       want it to occur, do not create /var/log/ksymoops.  If that directory exists, it should be owned by root and be mode 644  or  600  and  you
       should run script insmod_ksymoops_clean every day or so.

REQUIRED UTILITIES

       depmod(8), insmod(8).

NOTES

       Patterns supplied to modprobe will often need to be escaped to ensure that it is evaluated in the proper context.

BUGS

       modprobe [ -V | --version ] should exit immediately.  Instead, it prints the version information and behaves as if no options were given.

AUTHOR

       Jacques Gelinas (jack@solucorp.qc.ca)
       Bjorn Ekwall (bj0rn@blox.se)

Linux								 February 4, 2002						       MODPROBE(8)