Why is My Root File System Read-Only?
Anatomy of the Linux kernel
http://www.ibm.com/developerworks/linux/library/l-linux-kernel/
History and architectural decomposition
M. Tim Jones (mtj@mtjones.com), Consultant Engineer, Emulex Corp.
The Linux® kernel is the core of a large and complex operating system, and while it’s huge, it is well organized in terms of subsystems and layers. In this article, you explore the general structure of the Linux kernel and get to know its major subsystems and core interfaces. Where possible, you get links to other IBM articles to help you dig deeper.
Given that the goal of this article is to introduce you to the Linux kernel and explore its architecture and major components, let’s start with a short tour of Linux kernel history, then look at the Linux kernel architecture from 30,000 feet, and, finally, examine its major subsystems. The Linux kernel is over six million lines of code, so this introduction is not exhaustive. Use the pointers to more content to dig in further.