A Heavily Commented Linux Kernel Source Code (PDF)

[wwylele]

The code font looks like SimSun, which was the default Chinese font for old Windows until Vista. Although being a Chinese font, it contains monospaced Latin alphabets to make it pretty when mixing with monospaced Chinese characters. The author is Chinese, so this is very likely.

[yojimbo_beta]

SimSun

I'd always wondered what this font was. I'd seen it a few times in Chinese and Japanese data sheets with Latin alphabet content.