How to setup efi stub

get uuid of the root partition, also set the correct disk and partition in the commands and replace with current uuid of your root partition.

Make sure to change your cmdline parameters as you need them.

# Linux zen kernel
sudo efibootmgr --create --disk /dev/nvme0n1 --part 1 --label "Arch Linux" --loader /vmlinuz-linux-zen --unicode 'root=UUID="b3e4dcc5-be66-43e6-a66c-42c5d4a25e73" rootfstype=btrfs rootflags=subvolid=256 quiet loglevel=3 systemd.show_status=auto rd.udev.log_level=3 vt.global_cursor_default=0 nmi_watchdog=0 zswap.enabled=0 nvidia-drm.modeset=1 rcutree.rcu_idle_gp_delay=1 rw initrd=\amd-ucode.img initrd=\initramfs-linux-zen.img'

# linux lts kernel
sudo efibootmgr --create --disk /dev/nvme0n1 --part 1 --label "Arch Linux Lts" --loader /vmlinuz-linux-lts --unicode 'root=UUID="b3e4dcc5-be66-43e6-a66c-42c5d4a25e73" rootfstype=btrfs rootflags=subvolid=256 quiet loglevel=3 systemd.show_status=auto rd.udev.log_level=3 vt.global_cursor_default=0 nmi_watchdog=0 zswap.enabled=0 nvidia-drm.modeset=1 rcutree.rcu_idle_gp_delay=1 rw initrd=\amd-ucode.img initrd=\initramfs-linux-lts.img'

# linux zen kernel with debug
sudo efibootmgr --create --disk /dev/nvme0n1 --part 1 --label "Arch Linux Debug" --loader /vmlinuz-linux-zen --unicode 'root=UUID="b3e4dcc5-be66-43e6-a66c-42c5d4a25e73" rootfstype=btrfs rootflags=subvolid=256 nmi_watchdog=0 zswap.enabled=0 nvidia-drm.modeset=1 rcutree.rcu_idle_gp_delay=1 rw initrd=\amd-ucode.img initrd=\initramfs-linux-zen.img'