You're reading from Linux Kernel Debugging Leverage proven tools and advanced techniques to effectively debug Linux kernels and kernel modules

Product type Paperback

Published in Aug 2022

Publisher Packt

ISBN-13 9781801075039

Length 638 pages

Edition 1st Edition

Tools

Linux

Concepts

System Administration

Author (1):

Kaiwan N. Billimoria

View More author details

Table of Contents (17) Chapters

Preface

1. Part 1: A General Introduction and Approaches to Kernel Debugging

2. Chapter 1: A General Introduction to Debugging Software FREE CHAPTER

3. Chapter 2: Approaches to Kernel Debugging

4. Part 2: Kernel and Driver Debugging Tools and Techniques

5. Chapter 3: Debug via Instrumentation – printk and Friends

6. Chapter 4: Debug via Instrumentation – Kprobes

7. Chapter 5: Debugging Kernel Memory Issues – Part 1

8. Chapter 6: Debugging Kernel Memory Issues – Part 2

9. Chapter 7: Oops! Interpreting the Kernel Bug Diagnostic

10. Chapter 8: Lock Debugging

11. Part 3: Additional Kernel Debugging Tools and Techniques

12. Chapter 9: Tracing the Kernel Flow

13. Chapter 10: Kernel Panic, Lockups, and Hangs

14. Chapter 11: Using Kernel GDB (KGDB)

15. Chapter 12: A Few More Kernel Debugging Approaches

16. Other Books You May Enjoy

Debugging the kernel with KGDB

By now, I'll assume that you've configured and built a Linux target system suitable for KGDB (as described in detail in the previous section). It could be for any machine, including a guest system... Here, we'll continue to use the SEALS-generated ARM32 VExpress platform that we just set up as the target.

The intention here is to demo debugging the kernel early in the boot process with KGDB. To do so, the GDB server component within the target kernel will have to make it wait early in the boot process. This is so that the remote GDB client can connect to it. Linux supplies a boot parameter to do precisely this – it's named kgdbwait. To use it, you need to have a KGDB I/O driver built into the kernel image and specify which one via the kgdboc boot parameter (for example, kgdboc=/dev/ttyS0). You can also set it up later (on the console) by echoing the device name into the pseudofile /sys/module/kgdboc/parameters/kgdboc.

...