depmod(8)

NAME

   depmod - Generate modules.dep and map files.

SYNOPSIS

   depmod [-b basedir] [-e] [-E Module.symvers] [-F System.map] [-n] [-v]
          [-A] [-P prefix] [-w] [version]

   depmod [-e] [-E Module.symvers] [-F System.map] [-m] [-n] [-v]
          [-P prefix] [-w] [version] [filename...]

DESCRIPTION

   Linux kernel modules can provide services (called "symbols") for other
   modules to use (using one of the EXPORT_SYMBOL variants in the code).
   If a second module uses this symbol, that second module clearly depends
   on the first module. These dependencies can get quite complex.

   depmod creates a list of module dependencies by reading each module
   under /lib/modules/version and determining what symbols it exports and
   what symbols it needs. By default, this list is written to modules.dep,
   and a binary hashed version named modules.dep.bin, in the same
   directory. If filenames are given on the command line, only those
   modules are examined (which is rarely useful unless all modules are
   listed).  depmod also creates a list of symbols provided by modules in
   the file named modules.symbols and its binary hashed version,
   modules.symbols.bin. Finally, depmod will output a file named
   modules.devname if modules supply special device names (devname) that
   should be populated in /dev on boot (by a utility such as
   systemd-tmpfiles).

   If a version is provided, then that kernel version's module directory
   is used rather than the current kernel version (as returned by uname
   -r).

OPTIONS

   -a, --all
       Probe all modules. This option is enabled by default if no file
       names are given in the command-line.

   -A, --quick
       This option scans to see if any modules are newer than the
       modules.dep file before any work is done: if not, it silently exits
       rather than regenerating the files.

   -b basedir, --basedir basedir
       If your modules are not currently in the (normal) directory
       /lib/modules/version, but in a staging area, you can specify a
       basedir which is prepended to the directory name. This basedir is
       stripped from the resulting modules.dep file, so it is ready to be
       moved into the normal location. Use this option if you are a
       distribution vendor who needs to pre-generate the meta-data files
       rather than running depmod again later.

   -C, --config file or directory
       This option overrides the default configuration directory at
       /etc/depmod.d/.

   -e, --errsyms
       When combined with the -F option, this reports any symbols which a
       module needs which are not supplied by other modules or the kernel.
       Normally, any symbols not provided by modules are assumed to be
       provided by the kernel (which should be true in a perfect world),
       but this assumption can break especially when additionally updated
       third party drivers are not correctly installed or were built
       incorrectly.

   -E, --symvers
       When combined with the -e option, this reports any symbol versions
       supplied by modules that do not match with the symbol versions
       provided by the kernel in its Module.symvers. This option is
       mutually incompatible with -F.

   -F, --filesyms System.map
       Supplied with the System.map produced when the kernel was built,
       this allows the -e option to report unresolved symbols. This option
       is mutually incompatible with -E.

   -h, --help
       Print the help message and exit.

   -n, --show, --dry-run
       This sends the resulting modules.dep and the various map files to
       standard output rather than writing them into the module directory.

   -P
       Some architectures prefix symbols with an extraneous character.
       This specifies a prefix character (for example '_') to ignore.

   -v, --verbose
       In verbose mode, depmod will print (to stdout) all the symbols each
       module depends on and the module's file name which provides that
       symbol.

   -V, --version
       Show version of program and exit. See below for caveats when run on
       older kernels.

   -w
       Warn on duplicate dependencies, aliases, symbol versions, etc.

COPYRIGHT

   This manual page originally Copyright 2002, Rusty Russell, IBM
   Corporation. Portions Copyright Jon Masters, and others.

SEE ALSO

   depmod.d(5), modprobe(8), modules.dep(5)

AUTHORS

   Jon Masters <jcm@jonmasters.org>
       Developer

   Robby Workman <rworkman@slackware.com>
       Developer

   Lucas De Marchi <lucas.de.marchi@gmail.com>
       Developer

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