I learned a TON about the Linux kernel through writing custom device drivers for FPGAs. Granted most of my experience is in the driver area and not in any of th

I learned a TON about the Linux kernel through writing custom device drivers for FPGAs. Granted most of my experience is in the driver area and not in any of the subsystems, but even still I have a much better grasp of how the kernel operates now (and even more importantly, I know how to navigate it and how to find relevant documentation).