Book Image

Linux Kernel Debugging

By : Kaiwan N. Billimoria
Book Image

Linux Kernel Debugging

By: Kaiwan N. Billimoria

Overview of this book

The Linux kernel is at the very core of arguably the world’s best production-quality OS. Debugging it, though, can be a complex endeavor. Linux Kernel Debugging is a comprehensive guide to learning all about advanced kernel debugging. This book covers many areas in-depth, such as instrumentation-based debugging techniques (printk and the dynamic debug framework), and shows you how to use Kprobes. Memory-related bugs tend to be a nightmare – two chapters are packed with tools and techniques devoted to debugging them. When the kernel gifts you an Oops, how exactly do you interpret it to be able to debug the underlying issue? We’ve got you covered. Concurrency tends to be an inherently complex topic, so a chapter on lock debugging will help you to learn precisely what data races are, including using KCSAN to detect them. Some thorny issues, both debug- and performance-wise, require detailed kernel-level tracing; you’ll learn to wield the impressive power of Ftrace and its frontends. You’ll also discover how to handle kernel lockups, hangs, and the dreaded kernel panic, as well as leverage the venerable GDB tool within the kernel (KGDB), along with much more. By the end of this book, you will have at your disposal a wide range of powerful kernel debugging tools and techniques, along with a keen sense of when to use which.
Table of Contents (17 chapters)
1
Part 1: A General Introduction and Approaches to Kernel Debugging
4
Part 2: Kernel and Driver Debugging Tools and Techniques
11
Part 3: Additional Kernel Debugging Tools and Techniques

Technical requirements

With a few additions (which follow), the technical requirements and workspace remain identical to what's described in Chapter 1, A General Introduction to Debugging Software. The code examples can be found within the book's GitHub repository here: https://github.com/PacktPublishing/Linux-Kernel-Debugging.

In addition to the usual, you'll also need to install a few packages as well as a compressed root filesystem image we'll make use of later in the chapter:

  1. The QEMU ARM and x86 emulator apps and a few miscellaneous packages (all in, they take up close to 400 MB of disk space):
    sudo apt install qemu-system-arm qemu-system-x86 lzop libncursesw5 libncursesw5-dev p7zip-full
    • Navigate to the book's GitHub repo's ch11/ directory and download a compressed root filesystem image that we'll make use of later (in the Debugging kernel modules with KGDB section):
      cd <book_src>/ch11
      wget https://github.com/PacktPublishing/Linux...