Summary
Firstly, congratulations on completing this, our first chapter. Getting started is half the battle! You began by learning a bit about how the word debug came to be – equal parts myth, legend, and truth...
A key section was the brief description of some complex real-world cases of software gone wrong (several of them very unfortunate tragedies), where a software bug (or bugs) proved to be a key factor behind the disaster.
You understood that we're using the latest (at the time of this writing) 5.10 LTS kernel and how to set up the workspace (on x86_64, using either a native Linux system or Linux running as a guest OS). We covered the configuring and building of two custom kernels – a production and a debug one, with the production kernel geared toward high performance and security whereas the debug one was configured with several (most) kernel debug features turned on, in order to help catch bugs. I will assume you've done this for yourself, as future chapters will depend on it.
Finally, and I think very importantly, a few debugging tips and a small checklist wrapped up this chapter. I urge you to read through the tips and checklist often.
In the next chapter, you will learn that there can be, and are indeed, various approaches to debugging the Linux kernel (and its modules); you'll learn about them and which to use.
