MODPROBE.D(5) "kmod" "modprobe.d"
modprobe.d - Configuration directory for modprobe
@SYSCONFDIR@/modprobe.d/*.conf
/run/modprobe.d/*.conf
/usr/local/lib/modprobe.d/*.conf
@DISTCONFDIR@/modprobe.d/*.conf
/lib/modprobe.d/*.conf
Because the modprobe command can add or remove more than one module, due to modules having dependencies, we need a method of specifying what options are to be used with those modules. One can also use them to create convenient aliases: alternate names for a module, or they can override the normal modprobe behavior altogether for those with special requirements (such as inserting more than one module).
Note that module and alias names (like other module names) can have - or _ in them: both are interchangeable throughout all the module commands as underscore conversion happens automatically.
The configuration files contain one command per line, with blank lines and lines starting with '#' ignored (useful for adding comments). A '\' at the end of a line causes it to continue on the next line, which makes the files a bit neater.
See the COMMANDS section below for more.
Configuration files are read from directories in listed in SYNOPSIS in that order of precedence. Once a file of a given filename is loaded, any file of the same name in subsequent directories is ignored.
All configuration files are sorted in lexicographic order, regardless of the directory they reside in. Configuration files can either be completely replaced (by having a new configuration file with the same name in a directory of higher priority) or partially replaced (by having a configuration file that is ordered later).
NOTE: The configuration directories may be altered via the MODPROBE_OPTIONS environment variable. See the ENVIRONMENT section in modprobe(8).
alias wildcard modulename This allows you to give alternate names for a module. For example: "alias my-mod really_long_modulename" means you can use "modprobe my-mod" instead of "modprobe really_long_modulename". You can also use shell-style wildcards, so "alias my-mod* really_long_modulename" means that "modprobe my-mod-something" has the same effect. You can't have aliases to other aliases (that way lies madness), but aliases can have options, which will be added to any other options.
Note that modules can also contain their own aliases, which you can see
using *modinfo*. These aliases are used as a last resort (ie. if there
is no real module, *install*, *remove*, or *alias* command in the
configuration).blacklist modulename Modules can contain their own aliases: usually these are aliases describing the devices they support, such as "pci:123...". These "internal" aliases can be overridden by normal "alias" keywords, but there are cases where two or more modules both support the same devices, or a module invalidly claims to support a device that it does not: the blacklist keyword indicates that all of that particular module's internal aliases are to be ignored.
install modulename command This command instructs modprobe to run your command instead of inserting the module in the kernel as normal. The command can be any shell command: this allows you to do any kind of complex processing you might wish. For example, if the module "fred" works better with the module "barney" already installed (but it doesn't depend on it, so modprobe won't automatically load it), you could say "install fred /sbin/modprobe barney; /sbin/modprobe --ignore-install fred", which would do what you wanted. Note the --ignore-install, which stops the second modprobe from running the same install command again. See also remove below.
The long term future of this command as a solution to the problem of
providing additional module dependencies is not assured and it is
intended to replace this command with a warning about its eventual
removal or deprecation at some point in a future release. Its use
complicates the automated determination of module dependencies by
distribution utilities, such as mkinitrd (because these now need to
somehow interpret what the *install* commands might be doing. In a
perfect world, modules would provide all dependency information without
the use of this command and work is underway to implement soft
dependency support within the Linux kernel.
If you use the string "$CMDLINE_OPTS" in the command, it will be
replaced by any options specified on the modprobe command line. This can
be useful because users expect "modprobe fred opt=1" to pass the "opt=1"
arg to the module, even if there's an install command in the
configuration file. So our above example becomes "install fred
/sbin/modprobe barney; /sbin/modprobe --ignore-install fred
$CMDLINE_OPTS"options modulename option This command allows you to add options to the module modulename (which might be an alias) every time it is inserted into the kernel: whether directly (using modprobe modulename) or because the module being inserted depends on this module.
All options are added together: they can come from an *option* for the
module itself, for an alias, and on the command line.remove modulename command This is similar to the install command above, except it is invoked when "modprobe -r" is run.
softdep modulename pre: modules post: modules The softdep command allows you to specify soft, or optional, module dependencies. modulename can be used without these optional modules installed, but usually with some features missing. For example, a driver for a storage HBA might require another module be loaded in order to use management features.
pre-deps and post-deps modules are lists of names and/or aliases of
other modules that modprobe will attempt to install (or remove) in order
before and after the main module given in the _modulename_ argument.
Example: Assume "softdep c pre: a b post: d e" is provided in the
configuration. Running "modprobe c" is now equivalent to "modprobe a b c
d e" without the softdep. Flags such as --use-blacklist are applied to
all the specified modules, while module parameters only apply to module
c.
Note: if there are *install* or *remove* commands with the same
_modulename_ argument, *softdep* takes precedence.weakdep modulename modules The weakdep command allows you to specify weak module dependencies. Those are similar to pre softdep, with the difference that userspace doesn't attempt to load that dependency before the specified module. Instead the kernel may request one or multiple of them during module probe, depending on the hardware it's binding to. The purpose of weak module is to allow a driver to specify that a certain dependency may be needed, so it should be present in the filesystem (e.g. in initramfs) when that module is probed.
Example: Assume "weakdep c a b". A program creating an initramfs knows
it should add a, b, and c to the filesystem since a and b may be
required/desired at runtime. When c is loaded and is being probed, it
may issue calls to request_module() causing a or b to also be loaded.whitelist modulename Adds modulename to the whitelist of modules that are permitted to load. This command only has an effect once whitelist-enable is also given (in this or any other configuration file); by itself, a whitelist entry is parsed but has no effect.
whitelist-enable Enables whitelist enforcement: once this directive appears in any configuration file, only modules listed via whitelist commands (anywhere in the configuration) are permitted to load, and all other modules are denied. If whitelist-enable is given but no whitelist entries exist, every module is denied. Without whitelist-enable, no whitelist is enforced regardless of any whitelist entries present, and all modules may load as usual.
whitelist-test-mode Used together with whitelist-enable. Modules that the whitelist would otherwise deny are still permitted to load; a notice is logged instead, reporting which module would have been denied. This allows auditing the effect of a whitelist before enforcing it.
A future version of kmod will come with a strong warning to avoid use of the install as explained above. This will happen once support for soft dependencies in the kernel is complete. That support will complement the existing softdep support within this utility by providing such dependencies directly within the modules.
modprobe(8), modules.dep(5)