Loadable kernel modules in Linux are loaded (and unloaded) by the modprobe command. They are located in /lib/modules and have had the extension .ko ("kernel object") since version 2.6 (previous versions used the .o extension). The lsmod command lists the loaded kernel modules. In emergency cases, when the system fails to boot due to e.g. broken modules, specific modules can be enabled or disabled by modifying the kernel boot parameters list (for example, if using GRUB, by pressing 'e' in the GRUB start menu, then editing the kernel parameter line).