NAME¶
depmod - Generate modules.dep and map files.
SYNOPSIS¶
depmod [-b basedir]
[-o outdir] [-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.
-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 file or directory --config
file or directory
This option overrides the default configuration files.
See
depmod.d(5).
-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 Module.symvers --symvers
Module.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 System.map --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.
AUTHORS¶
Numerous contributions have come from the linux-modules mailing
list <linux-modules@vger.kernel.org> and Github. If you have a clone
of kmod.git itself, the output of git-shortlog(1) and
git-blame(1) can show you the authors for specific parts of the
project.
Lucas De Marchi <lucas.de.marchi@gmail.com> is the
current maintainer of the project.