Pure UEFI Boot Guide

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This tutorial will show you how to install Funtoo on a UEFI system. UEFI, also known as the Unified Extensible Firmware Interface, is a new firmware interface that is used on some newer computers as a replacement for the traditional PC BIOS. It has an integrated boot loader, so setting up booting is different. The recommended approach is to follow the. Many have reported that they are now unable to boot their system using the other, older method. This tutorial is meant to be an "overlay" over the Regular Funtoo Installation. Follow the normal installation and only follow steps in this tutorial when dealing with partitioning and configuring the boot loader (GRUB). All steps are otherwise identical to the regular installation process.

What Are We Doing?

This guide will show you how to set up your UEFI system with EFI-stub method.

First Steps

To install Funtoo Linux on a UEFI system, first you need to boot SysRescueCD in UEFI mode. To do this, enable UEFI in your BIOS, and if necessary disable legacy booting. After some fiddling, you should be able to boot SysRescueCD and get a black and white text menu instead of the traditional aqua/cyan-colored menu. The black and white menu indicates that you booted SysRescueCD in UEFI mode. Once you've accomplished this, you're ready to continue with your Funtoo Linux installation and partition your drive. See below for details.


If the /sys/firmware/efi directory exists, then you have successfully booted in EFI mode and will be able to configure your Funtoo system to boot in EFI mode. If the directory doesn't exist, fix this first. It is a requirement for setting up EFI booting.


To set up your partitions for UEFI booting, you will create a ~500MB FAT32 partition on /dev/sda1, and set it to type EF00 using gdisk.

root # gdisk /dev/sda
Command: n ↵
Partition Number: 1 ↵
First sector: 
Last sector: +500M ↵
Hex Code: EF00

This partition will serve as your Funtoo /boot filesystem as well as the partition that the UEFI firmware can read to load GRUB. Then you will set up swap on /dev/sda2 and your root filesystem on /dev/sda3. To create the FAT32 filesystem, type:

root # mkfs.vfat -F 32 /dev/sda1

Your /etc/fstab entry for this filesystem will also differ, and will look like this:

/dev/sda1		/boot		vfat		noatime	1 2



Make sure you add VFAT support to your kernel if you are building it manually.

EFI Framebuffer

If you have the following option enabled in your kernel, then uvesafb and efifb will not be able to detect the framebuffer:

Under Bus options (PCI etc.):

[*] Mark VGA/VBE/EFI FB as generic system framebuffer (NEW)

If you have that option enabled, you must also enable:

Under Device Drivers-->Graphics support-->Frame buffer Devices:

[*]   Simple framebuffer support

This is the preferred method of using the EFI framebuffer, the efifb and uvesafb drivers will be used as a fallback if the above is not compatible.

Boot Loader

EFI Stub method

Instead of bothering with the installation of GRUB and the risk that your system will not boot, you should consider using the UEFI firmware of your computer to boot your kernel. not only does this method reduce boot times slightly, it also removes the hassel of dealing with and configuring a bootloader.

Kernel Configuration

To prepare your kernel to boot with EFI stub, make sure that the following options are built in to your kernel: Under Processor type and features:

[*] EFI runtime service support
[*]     EFI stub support
[ ]         EFI mixed-mode support

[*] Built-in kernel command line
(kernel options that you want to pass go here)

Building and installing the kernel

After you have configured your kernel, build it, install it to /boot, and then create a copy of the image to store in the EFI boot directory:

root # cd /usr/src/linux
root # make -jn (replace 'n' with CPU core numbers)
root # make -jn install modules_install
root # mkdir -vp /boot/EFI/Boot
root # cp -v /boot/vmlinuz-x.x.x /boot/EFI/Boot/bootx64.efi

You should be able to reboot and enjoy yor new Funtoo system!