Linux Kernel – How to List All Loadable Kernel Modules

kernel-moduleslinux-kernel

I'm looking for a few kernel modules to load i2c-dev and i2c-bcm2708. But the modprobe command returns:

sudo modprobe i2c-dev
modprobe: module i2c-dev not found in modules.dep

How can I list all the available modules in the system? In which directory are they located?

Best Answer

  • By default modprobe loads modules from kernel subdirectories located in the /lib/modules/$(uname -r) directory. Usually all files have extension .ko, so you can list them with

    find /lib/modules/$(uname -r) -type f -name '*.ko'

    or, taking into account compressed files:

    find /lib/modules/$(uname -r) -type f -name '*.ko*'

  • Each module can be also loaded by referring to its aliases, stored in the /lib/modules/$(uname -r)/modules.alias (and modules.alias.bin).

  • However, to load a modules successfully modprobe needs their dependencies listed in the file /lib/modules/$(uname -r)/modules.dep (and a corresponding binary version modules.dep.bin). If some module is present on the system, but is not on the list, then you should run a command depmod which will generate such dependencies and automatically include your module to modules.dep and modules.dep.bin.

  • Additionally, if the module is successfully loaded it will be listed in the file /proc/modules (also accessed via command lsmod).

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