The Linux kernel has a modular design. At boot time, only a minimal
resident kernel is loaded into memory. Thereafter, whenever a user
requests a feature that is not present in the resident kernel, a kernel
module is dynamically loaded into memory. After a specified period of
inactivity, the module may be removed from memory.
The mechanism that supports dynamic loading of modules is a kernel
thread called kmod. Modules are not loaded unless
they are needed. When the kernel requests a
module, the module is loaded along with all its module dependencies.
When you install Red Hat Linux, the hardware on your system is probed and you
provide information about how the system will be typically used and
which programs should be loaded. Based on this probing and the
information you provide, the installation program decides which features
to compile into the resident kernel and which to put in loadable
modules. The installation program sets up the dynamic loading mechanism
to work transparently. If you build your own custom kernel,
you can make all of these decisions for yourself.
If you add new hardware after installation and the hardware requires a
kernel module, you need to set up the dynamic loading
mechanism. Kudzu usually detects new
hardware. You can also add the new driver by editing the module
configuration file, /etc/modules.conf.
For example, if your system included a model SMC EtherPower 10 PCI
network adapter at the time of installation, the module configuration
file will contain this following line:
After installation, if you install a second identical network adapter to
your system, add the following line to
/etc/modules.conf:
See the Official Red Hat Linux Reference Guide for an alphabetical list of
kernel modules and the hardware supported by the modules.
