The book is available in HTML form at https://mit-pdos.github.io/xv6-riscv-book/.
The book is available in PDF form at https://mit-pdos.github.io/xv6-riscv-book/book.pdf.
This edition of the book has been converted to LaTeX.
In order to build it, ensure you have a TeX distribution that contains
the pdflatex command. With that, you should be able to build the book
by running make, which will clone the OS itself and build the book
to book.pdf in the main directory.
Figures are drawn using inkscape.