Linux Kernel in a Nutshell

Chapter 7. Customizing a Kernel

One of the hardest parts of building your own version of the Linux kernel is determining exactly which drivers and configuration options are needed for your machine to work properly. This chapter will walk you through this process of finding and selecting the correct drivers.

Using a Distribution Kernel

One of the easiest ways to determine which modules are necessary is to start with the kernel configuration that comes with your distribution's kernel package. It is also much easier to determine which drivers are needed on a running system, where the proper drivers are already bound to the hardware.

If you do not already have a Linux distribution installed on the machine that you are building the kernel for, use a LiveCD version of a distribution. This allows you to boot Linux on the machine and determine what kernel configuration options are needed in order to get the hardware working properly.

Where Is the Kernel Configuration?

Almost all distributions provide the kernel configuration files as part of the distribution kernel package. Read the distribution-specific documentation for how to find these configurations. It is usually somewhere below the /usr/src/linux/ directory tree.

If the kernel configuration is hard to find, look in the kernel itself. Most distribution kernels are built to include the configuration within the /proc filesystem. To determine if this is true for your running kernel, enter:

$ ls /proc/config.gz
/proc/config.gz

If the /proc/config.gz ...