The lab machine
Why QEMU is the spine of every lab here, what to install on the host, and what each lab host badge means.
Getting the source
Cloning or downloading the pinned kernel, what the repository costs in disk and time, and a first orientation pass through the tree.
Building a kernel
From defconfig to a bootable image, including the debug options that make the rest of this section's labs possible.
A minimal rootfs
A static BusyBox, a directory skeleton, and an /init packed into an initramfs — early user space made concrete instead of magical.
Booting in QEMU
The canonical QEMU invocation every later lab reuses, explained flag by flag.
GDB on the kernel
Attaching a debugger to the virtual CPU, loading vmlinux symbols, and walking live kernel structures — the highest-leverage skill in this section.
Full VM and WSL2
A Debian VM for the labs that need systemd and real block devices, then an honest account of which labs WSL2 can and cannot run.