UEFI Bare Bones

A minimal "Hello World" kernel.

Prerequisites

• git, wget, meson, the text editor of your choice, …
• clang with lld-link

Building

Set up a build directory. Run meson setup --cross-file uefi.cross-file <your build directory>. In the build directory, run ninja.

Example:

mkdir -p build
meson setup --cross-file=uefi.cross-file build
cd build
ninja

Running

Make sure you have a OVMF.fd ready. If you have a OVMF package installed, it can usually be copied from a path like /usr/share/ovmf/x64/.

Set up an ESP in the build directory like this:

cp /usr/share/ovmf/x64/OVMF.fd .
mkdir -p esp/EFI/BOOT/
cp BOOTX64.EFI esp/EFI/BOOT

After this, you can run QEMU. A recommended setup looks like this:

qemu-system-x86_64 -drive if=pflash,format=raw,file=OVMF.fd -M accel=kvm:tcg -net none -serial stdio -drive format=raw,file=fat:rw:esp