depmod

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

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 (Aqs module directory is used rather than the current kernel version (as returned by uname-r ).

-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 fileor 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 (Aq_ (Aq) to ignore .

-v , --verbose In verbose mode, depmod will print (to stdout) all the symbols each module depends on and the module (Aqs 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 .

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

JonMasters < jcm@jonmasters .org > Developer

RobbyWorkman < rworkman@slackware .com > Developer

LucasDe Marchi < lucas .de .marchi@gmail .com > Developer

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