This book is very easy to read, this is simply because Robert presented the material in such a way and it should not be taken for granted.

If you're going to work on or within Linux, you'll have to start reading the code sooner or later. But this book can point the way and shine some light on your first few steps, and I do recommend it. Another good thing is that the text is not a regurgitation of other reference material or filled with useless code print-outs.

It is generally concise and to-the-point and doesn't insult your intelligence (maybe because the author is a "real" developer). One notable exception is that it actually tries to teach basic concepts such as context switching, locking, and synchronization, etc. If you don't have the proper technical background, not only you don't learn it from this half-baked description, but you also have no business messing in the kernel anyway!

The book is a real easy read, Robert Love makes it really easy to understand what hes talking about.
The book does lack lots of extra information for the more in-depth inner workings of the kernel, however I find this book easier to read.
I read it before reading Understanding the Linux Kernel, which has much more in-depth information

Linux is a amazing operating system. It has grown leaps and bounds. As the OS has matured so much it is impossible for one person to be skim the entire code and understand. The book does a wonderful job. Every thing from bottom half handlers, IO schedulers, process contexts all are explained in full detail. I wish they will come up one more edition to explain rest of the stuff like SCSI subsystem etc. etc. This is a must buy for any one interested in Linux. Even if you are expert in Linux kernel this book will surprise you with hidden details. Must Must Must buy.

This book explains basic operating systems concepts and then describes how this concepts are implemented in Linux.
The text covers most of kernel architecture and there is a detailed description of the main Linux Kernel data structures and algorithms.
The book can be understood by any technical professional/student with some C language skills.
I highly recommend this book for anyone interested in Linux Kernel or operating systems in general.