depmod(8) — Linux manual page


DEPMOD(8)                        depmod                        DEPMOD(8)

NAME         top

       depmod - Generate modules.dep and map files.

SYNOPSIS         top

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

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

DESCRIPTION         top

       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

       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         top

       -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.

       -o outdir, --outdir outdir
           Set the output directory where depmod will store any
           generated file.  outdir serves as a root to that location,
           similar to how basedir is used. Also this setting takes
           precedence and if used together with basedir it will result
           in the input being that directory, but the output being the
           one set by outdir.

       -C, --config file or directory
           This option overrides the default configuration directory at

       -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
           Supplied with the 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.

           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.

           Warn on duplicate dependencies, aliases, symbol versions,

COPYRIGHT         top

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

SEE ALSO         top

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

AUTHORS         top

       Jon Masters <>

       Robby Workman <>

       Lucas De Marchi <>

COLOPHON         top

       This page is part of the kmod (userspace tools for managing
       kernel modules) project.  Information about the project can be
       found at [unknown -- if you know, please contact man-] If you have a bug report for this manual page,
       send it to  This page was obtained
       from the project's upstream Git repository
       ⟨git://⟩ on
       2023-12-22.  (At that time, the date of the most recent commit
       that was found in the repository was 2023-12-06.)  If you
       discover any rendering problems in this HTML version of the page,
       or you believe there is a better or more up-to-date source for
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       manual page), send a mail to

kmod                           12/22/2023                      DEPMOD(8)

Pages that refer to this page: depmod.d(5)modules.dep(5)insmod(8)kernel-install(8)kmod(8)lsmod(8)modprobe(8)rmmod(8)