Chapter 37. Kernel Modules

Chapter 37. Kernel Modules

37.1. Kernel Module Utilities
37.2. Persistent Module Loading
37.3. Additional Resources
37.3.1. Installed Documentation
37.3.2. Useful Websites

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, sometimes referred to as a driver, is dynamically loaded into memory.

During installation, the hardware on the system is probed. Based on this probing and the information provided by the user, the installation program decides which modules need to be loaded at boot time. The installation program sets up the dynamic loading mechanism to work transparently.

If new hardware is added after installation and the hardware requires a kernel module, the system must be configured to load the proper kernel module for the new hardware. When the system is booted with the new hardware, the Kudzu program runs, detects the new hardware if it is supported, and configures the module for it. The module can also be specified manually by editing the module configuration file, /etc/modprobe.conf.

Note

Video card modules used to display the X Window System interface are part of the xorg-X11 packages, not the kernel; thus, this chapter does not apply to them.

For example, if a system included an SMC EtherPower 10 PCI network adapter, the module configuration file contains the following line: 

alias eth0 tulip

If a second network card is added to the system and is identical to the first card, add the following line to /etc/modprobe.conf: 

alias eth1 tulip

Refer to the Red Hat Enterprise Linux Reference Guide for an alphabetical list of kernel modules and supported hardware for those modules.


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