It took me some Googling and experiments before I saw it work the first time: an EFI boot inside QEMU. I was blown away.

What is an EFI boot in QEMU good for? Two things:

1. To predict about future bootability on actual EFI hardware.

2. To make a Linux installer work with WLAN as if it's LAN.

My case was a bit of both combined, but that's a story for another post.

To have QEMU do an EFI boot, besides QEMU it takes:

• OVMF installed (e.g. package sys-firmware/edk2-ovmf on Gentoo)

• An EFI-only test image for proof (e.g. MemTest86 5.x or later)

Then:

wget https://www.memtest86.com/downloads/memtest86-usb.zip
unzip memtest86-usb.zip

sudo qemu-system-x86_64 \
    -enable-kvm -m 2G \
    -bios /usr/share/edk2-ovmf/OVMF_CODE.fd \
    -drive file=memtest86-usb.img,format=raw

Nice!

Arguments -enable-kvm -m 2G are optional and just make things run faster. The location of BIOS file OVMF_CODE.fd depends on your Linux distrubution:

• Arch Linux: /usr/share/edk2-ovmf/x64/OVMF_CODE.fd

• Debian, Ubuntu: /usr/share/OVMF/OVMF_CODE.fd (not /usr/share/qemu/OVMF.fd)

• Fedora: /usr/share/edk2/ovmf/OVMF_CODE.fd

• Gentoo: /usr/share/edk2-ovmf/OVMF_CODE.fd

Enough EFI for today.

Best, Sebastian