insmod vs modprobe

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Both utilities are used to load the given module

insmod
modprobe
Loads the module given
insmod /path/to/module.ko
Loads the module only in /lib/modules/$(uname -r)
modprobe /home/test/hello.ko will not work
Dependencies if present are not loaded
modprobe calculates dependencies , loads the dependencies and then the main module


How modprobe calculates dependencies?

Modprobe depends on depmod tool to calculate dependencies. depmod calculates dependencies of all the  modules present in /lib/modules/$(uname -r) folder, and places the dependency information in /lib/modules/$(uname -r)/modules.dep file

E.g. kernel/drivers/net/wireless/admtek/adm8211.ko: kernel/net/mac80211/mac80211.ko kernel/net/wireless/cfg80211.ko      kernel/drivers/misc/eeprom/eeprom_93cx6.ko

In this case, eeprom_93cx6.ko, cfg80211.ko is loaded first and then adm8211.ko

Modules are loaded right  to left and removed left to right. So while removing adm8211.ko is removed, then cfg80211.ko and finally eeprom_93cx6.ko

We can re-load the modules.dep file by running "depmod -a" command


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