Learning Linux Kernel Development

1. ./build builds a Linux Kernel bzImage (inside a build container, it's just easier for dependencies) and userland demo images such as: (You can use any Docker Container image as User Land, see image2initrd, as long as it has an /init).

   • hello: a minimal "hello, world" /init static binary runnable in a FROM scratch demo container
   • busybox-init: a busybox-based container with bash as init and working networking

2. ./run-qemu hello starts this Kernel in a virtual machine (using KVM, with QEMU; enable virtualization first), with an initrd containing our hello demo.

3. ./run-qemu busybox-init starts this Kernel in a virtual machine using the busybox container image plus our own init as initrd. You can quit it using poweroff -f. Also see networking.

4. ./run-qemu-syslinux hello | busybox-init builds a disk image with SYSLINUS bootloader, and starts virtual machine. (Whereas run-qemu uses qemu* -kernel -initrd.)

5. The /tmp/bzImage-busybox-init.img disk image can be written to a USB key (e.g. using dd, or, easier, GNOME Disks), and will boot on bare metal.

6. ./run-dev-container will run an interactive dev container to explore [tux@kernel-dev ~]. Its root password is empty, so you can e.g. sudo dnf install -y .., but it's (intentionally) ephemeral - script it! ;)

7. ./test.tcl automatically tests everything that's described above; run it after making any changes (and extend it when adding new features).

docs/ has more background and details; including a Roadmap and TODOs. Architecture (future, TBD) further describes what's what in this repo.

archlinux has my Arch Linux based distro.

by Michael Vorburger.ch