In order to be able to use this book, you need to be confident with C programming. A little Unix expertise is needed as well, as we often refer to Unix commands and pipelines.

At the hardware level, no previous expertise is required to understand the material in this book, as long as the general concepts are clear in advance. The text isn’t based on specific PC hardware, and we provide all the needed information when we do refer to specific hardware.

Several free software tools are needed to build the kernel, and you often need specific versions of these tools. Those that are too old can lack needed features, while those that are too new can occasionally generate broken kernels. Usually, the tools provided with any current distribution will work just fine. Tool version requirements vary from one kernel to the next; consult Documentation/Changes in the source tree of the kernel you are using for exact requirements.