depmod

DEPMOD(8)                           depmod                           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] [-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

kmod                              01/28/2022                         DEPMOD(8)