USING GRUB ON UEFI
AUTHORS: Dan McGhee, Kevin M. Buckley
DATE: 2017-10-22
LICENSE: GNU Free Documentation License Version 1.2
SYNOPSIS: Boot LFS by default in a UEFI Environment using GRUB
DESCRIPTION:
This hint contains the information to direct the OS Boot Manager to default
to the GRUB in a UEFI environment employing EFI Mode. This hint applies to
only x86_64 machines.
This version, hereafter referred to as "the 2017-10-22 hint", updates Dan
McGhee's original, dated 2014-10-16.
The 2017-10-22 hint saw the UEFI packages built against an LFS 7.10 SysV
installation that was already being booted using the existing host system's
bootloaders.
Where possible, changes to the 2017-01-22 hint have been made so that it
should be obvious where the the 2017-01-22 and 2014-10-16 hint's differ.
ATTACHMENTS:
* None
PREREQUISITES:
Base LFS system before or after Ch. 8
Basic understanding of obtaining and building packages
HINT:
DISCLAIMER: The recipes in this hint neither supplant nor supersede the
build instructions in a stable version of either the LFS or BLFS books.
They merely augment them for newer firmware. If conflicts arise between
this hint and the instructions in the book, take the issue to the mailing
lists. Additionally, this hint applies to only x86_64 machines packaged
with Windows 7 or Windows 8. The recipes here can be used on Mac OS, but
have not been investigated at the initial writing of this hint.
The 2017-01-22 hint refers to an LFS 7.10 system, built onto an x86_64
machine from within a CentOS 6 host, that had had never had a version of
windows installed on it, indeed the host contained three EFI directories
below "/boot/efi/EFI/", namely centos, redhat, and ubuntu, these having
been installed from CentOS 6.8, Fedora Core 20 and Ubuntu 12.04 OSes
respectively.
USE OF TERMS: The following is a use of terms in this hint. Further
information for and amplification of them can be found in References 1-3.
BIOS Settings: A firmware interface accessed by the keyboard after power
is applied. In it a user can change the order and way of how the computer
boots.
BIOS System: Firmware with an MBR
EFI Mode: A condition of the booted system in which the EFI partition is
mounted and the uefi (efi) variable support in the kernel is working
properly. It results from enabling UEFI Mode in BIOS Settings.
EFI Mount Point: A user defined mount point for the EFI Partition. In
this hint, and in most distros, it is /boot/efi.
EFI Partition: A small partition, usually before any other partitions;
i.e., /dev/sda1 of 200-250 Mb, formatted in FAT32 with the /boot flag, in
parted, or ef00 (EF00) partition type in gdisk. (NOTE: The boot flag has a
different function and meaning in MBR partitioned disks.)
efi variables (synonymous: uefi variables): variables through which the
operating system can interact with the firmware.
Legacy Boot Option (Legacy Boot): A boot process in BIOS Settings that
disables UEFI booting and uses CIM.
GUID Partition Table (GPT): A partitioning scheme that uses UUID's instead
of cylinders to identify partitions.
PRELIMINARY DISCUSSION: Additional information and more in depth
discussion of the following concepts can be found using References 1-3.
Booting LFS is no longer as simple as "grub-install /dev/sda." There are
more options and more considerations. With the advent and proliferation of
UEFI firmware, a user's knowledge and philosophy of the boot
process requires expansion:
a) GPT partitioning is different from MBR partitioning. The tool fdisk
is not able to manipulate GPT partitions. Parted and gdisk (from
gptfdisk) are the tools to use. Each has their pros and cons,
supporters and detractors. Either one or both can be used.
b) UEFI firmware uses Boot Managers to select Boot Loaders like GRUB or
LILO. They, themselves do not boot the machine.
c) The Boot Loaders are placed on the EFI partition rather than the
MBR. This concept is similar and parallel to the LFS procedures of
using a separate /boot partition.
d) There are additional tools that LFS needs in order to accomplish
this mode of booting.
e) LFS can be built and booted as the instructions are written up to
and including LFS-7.10. To do this on UEFI firmware, the BIOS
Settings must be changed to Legacy Options from UEFI Options.
One of the hugely discussed issues surrounding UEFI is Secure Boot. It is
necessary to understand that the terms "UEFI" and "Secure Boot" are NOT
synonymous. UEFI is firmware. Secure Boot is a process of using "keys" to
"guarantee" the safety and authenticity of a Boot Loader. NOTE: To use
the recipes in this hint, Secure Boot must be disabled in the BIOS Boot
Settings.
Please note that the recommended order for implementing these recipes is a
departure from the build order in LFS. The most convenient, and arguably
the most practical way, to implement the recipes here is to use them in the
of build of an LFS System at the end of Ch. 6. Building the BLFS and
non-BLFS packages has been tested both inside and outside of the chroot
environment. Then, following the book, proceed through Ch. 7, returning to
the recipes in Ch. 8. The recipes are presented in that order.
The most inconvenient way to implement these recipes is in a completely
functional LFS-7.10, or earlier, system. This involves uninstalling
grub-2.02, removing it from its location as a result of grub-install and
implementing the recipes. Migrating from Legacy Boot to UEFI boot is
possible. At the initial writing of this hint, however, it is not
included. References 1-3 contain more information on this subject.
The last consideration in implementing the recipes here is GRUB's graphical
terminal. In UEFI systems, if the GRUB video mode is not initialized, no
kernel boot messages will appear until the kernel video takes over. The
GRUB package does not supply fonts, and GRUB defaults to unicode.pf2.
There are two ways to supply this font. The first is to copy unicode.pf2
from the host system to /boot/grub on the LFS system. The second method
involves configuring grub to build grub-mkfont, and this creates a build
dependency of Freetype2 for GRUB. This hint addresses both situations.
Finally, as of the initial writing of this hint, there is no standard for
the use of UEFI and the implementation of Secure Boot. These are hugely
manufacturer dependent. This hint uses terms used in the original author's
hardware. They may be different in other manufacturers' implementations.
However, the capabilities to do the boot setup operations contained in this
hint will exist on each machine. The terms may differ, and more than one
operation might be needed to achieve a desired goal. For example, someone
may need to disable Secure Boot and remove Secure Keys.
RECIPES:
[NOTE] The recipes are written with the assumption that the packages are
being built in the chroot environment before the end of Ch. 8. They can be
modified, with little difficulty, to be used in a functional system.
CHECKING EFI-MODE
Before entering the chroot environment, check that the host booted in
EFI Mode.
ls /sys/firmware/efi
If this directory exists and is populated, the host booted in EFI Mode.
MOUNT EFI PARTITION
Determine which device is the EFI partition using gdisk or parted,
enter the chroot environment, create /boot/efi if needed, and
mount -vt vfat /dev/sda(x) /boot/efi
where sda(x) is the device containing the EFI partition.
BUILD DEPENDENCIES:
Install the following BLFS packages, using the instructions in the book:
popt and pciutils. Build and install Freetype2 if building grub with
grub-mkfont enabled.
The BLFS 7.10 Freetype2 instructions recommend that it be built after
"which" and "libpng" have been installed, so it was, however, as the
recommendation for "HarfBuzz" notes that one builds Freetype2 without
it first, and then do a re-install, it wasn't thought necessary to do
the re-install.
The "libpng" install did include the "apng" patch.
The BLFS 7.10 instructions for popt explicitly
"prevents installtion of the static versions of the libraries"
however the build of efivars appears to require those.
In order to follow the BLFS book and then explicity alter things for
an installtion of UEFI-related packages, following the BLFS books
instructions, and then doing
tar xf /path/to/BLFS-SRCS-7.10/popt-1.16.tar.gz
cd popt-1.16/
./configure --prefix=/usr --enable-static
make
make install
appears to do the right thing.
DOSFSTOOLS 3.0.28 (runtime dependency of efibootmgr)
Note: As of October 3, 2014, dosfstools was tagged "orphaned.
It is still functional.]
Download:
https://github.com/dosfstools/dosfstools/releases/download/v3.0.28/dosfstools-3.0.28.tar.xz
Build and Installation:
tar xf /path/to/EXTRA-SRCS-7.10/dosfstools-3.0.28.tar.xz
cd dosfstools-3.0.28/
make PREFIX=/usr SBINDIR=/usr/bin MANDIR=/usr/share/man \
DOCDIR=/usr/share/doc
make LANGUAGES="" PREFIX=/usr SBINDIR=/usr/bin MANDIR=/usr/share/man \
DOCDIR=/usr/share/doc install
Note that the LANGUAGES="" prevents the install from creating all manner
of directories below /use/share/man, but if you want those, leave it out.
EFIVAR-30 (depends on popt)
The 2014-10-16 hint pointed to a user's GitHub branch of the main code
that is now available as part of Fedora's GitHub repository.
Note also that the numbering scheme has changed slightly.
Furthermore, the EFIVAR-30's Makefiles have altered the way in which
the codebase is built
Download:
https://github.com/rhinstaller/efivar/releases/download/30/efivar-30.tar.bz2
Compile the package:
tar xf /path/to/EXTRA-SRCS-7.10/efivar-30.tar.bz2
cd efivar-devel-30/
cp -p Make.defaults Make.defaults.dist
sed 's|-O2|-Os|g' -i Make.defaults
cp -p src/test/Makefile src/test/Makefile.dist
sed 's|-rpath=$(TOPDIR)/src/|-rpath=$(libdir)|g' \
-i src/test/Makefile
make libdir="/usr/lib/" bindir="/usr/bin/" \
mandir="/usr/share/man/" \
includedir=/usr/include/" V=1 -j1
Install the package:
make -j1 V=1 DESTDIR="${pkgdir}/" libdir="/usr/lib/" \
bindir="/usr/bin/" mandir="/usr/share/man" \
includedir="/usr/include/" install
install -v -D -m0755 src/test/tester /usr/bin/efivar-tester
Running the "make test" that the package's documentation suggests, gave a
rather strange error message,
# make test
## ...
## About to test thirtythree
## testing efi_set_variable()
## testing efi_get_variable_size()
## testing efi_get_variable()
## testing efi_get_variable_attributes()
## testing efi_del_variable()
## testing efi_append_variable()
## testing efi_get_variable()
## testing efi_del_variable()
## About to test tentwentyfour
## testing efi_set_variable()
## testing efi_get_variable_size()
## testing efi_get_variable()
## testing efi_get_variable_attributes()
## testing efi_del_variable()
## testing efi_append_variable()
## FAIL: "tentwentyfour"(line 197) (-1) append test failed: No space left on device
however at time of writing, thoughts on this haven't been forthcoming
from the EFIVAR community,
https://github.com/rhinstaller/efivar/issues/78
though it doesn't appear to prevent things working as expected.
EFIBOOTMGR-14
(depends on pciutils, efivars,zlib to build and dosfstools to run.)
See notes to EFIVAR package as regards changes to download URI
Note also that compared to the 2014-10-16 hint, efibootmgr's source
directory layout has changed,
Download: https://github.com/rhinstaller/efibootmgr/releases/download/14/efibootmgr-14.tar.bz2
Compile the package:
tar xf /path/to/EXTRA-SRCS-7.10/efibootmgr-14.tar.bz2
cd efibootmgr-14/
make
Install the package:
install -v -D -m0755 src/efibootmgr /usr/sbin/efibootmgr
install -v -D -m0644 src/efibootmgr.8 \
/usr/share/man/man8/efibootmgr.8
install -v -D -m0644 src/efibootdump.8 \
/usr/share/man/man8/efibootdump.8
GRUB-2.02~beta3 (depends on freetype2 if grub-mkfont is desired
and on efibootmgr, efivars and efivarfs at run time.)
Download: http://alpha.gnu.org/gnu/grub/grub-2.02~beta3.tar.xz
Prepare for compilation:
tar xf /path/to/LFS-SRCS-7.10/grub-2.02~beta3.tar.xz
cd grub-2.02~beta3/
./configure --prefix=/usr \
--sbindir=/sbin \
--sysconfdir=/etc \
--disable-efiemu \
--enable-grub-mkfont \
--with-platform=efi \
--target=x86_64 \
--program-prefix="" \
--with-bootdir="/boot" \
--with-grubdir="grub" \
--disable-werror
Command explanation:
--enable-grub-mkfont This creates the build dependency on
Freetype2. To remove this dependency do not use this switch
and copy unicode.pf2 from the host system to /boot/grub of the
LFS partition. Alternatively, it can be downloaded from the
internet.
--program-prefix="" is a matter of convenience. If not used,
"x86_64" is inserted in all the grub executables. For
example, "grub-install" and "grub-mkconfig" become
x86_64-grub-install and x86_64-grub-mkconfig.
--with-platform=efi and --target=x86_64 are mandatory for the efi
and x86_64 build
The other configure options added to the ones in LFS-7.10 and
LFS-SVN were employed to insure that grub is built and installed
in the directories used in this hint. They may be used or
eliminated based on individual use and preference.
Compile the package:
make
Install the package:
make install
Post installation of the Unifont files, do a
grub-mkfont -o /usr/share/grub/unicode.pf2 > \
/usr/share/fonts/unifont/unifont.pcf
UNIFONT 9.0.06
In the 2014-01-16 hint, the Unifont installtion got a mention further
down but as the 2017-01-22 hint's build made use of those fonts, they're
here
Download: http://unifoundry.com/pub/unifont-9.0.06/font-builds/unifont-9.0.06.pcf.gz
Install the font files
mkdir -pv /usr/share/fonts/unifont
gunzip -c /path/to/EXTRA-SRCS-7.10/unifont-9.0.06.pcf.gz > \
/usr/share/fonts/unifont/unifont.pcf
LFS CHAPTER 7:
When constructing the file /etc/fstab, add the following lines:
/dev/sda(x) /boot/efi vfat defaults 0 1
efivarfs /sys/firmware/efi/efivars efivarfs defaults 0 1
where /dev/sda(x) is the EFI partion
Notes:
1) If you are going to be booting your UEFI-aware LFS system using a
non-LFS Grub from your host AND if that Grub is one (eg Fedora)
that allows for the kernel to be specified using that Grub's
"linuxefi" attribute, so
linuxefi /path/to/kernel root=/path/to/root ro
then you don't appear to need the /etc/fstab line, and indeed,
you'll get told during the boot that the mounter knows nothing
about the efivars filesystem type.
However, LFS's efibootmgr will still be capable of interrogating
your UEFI environment.
2) If the LFS system is booted from the LFS+Hint's grub, which doesn't
appear to know about the "linuxefi" attribute so using
linux /path/to/kernel root=/path/to/root ro
then, unless you have the efivars filesystem mounted, and you are
able to, then LFS's efibootmgr will be NOT capable of interrogating
your UEFI environment, and you'll be told that there is no efivars
filesystem
LFS CHAPTER 8:
KERNEL CONFIGURATION OPTIONS FOR EFI
The LFS 7.10 kernel build's "make defconfig" populated a good number of
the EFI-related options on my UEFI-enabled hardware, however, so as to
make the 2014-10-16 hint's list of settings easier to find when coming
to alter/set things, here is the list of the options along with the
location of the various checkboxes and the settings they should have,
as seen when starting from a "make menuconfig"
## CONFIG_EFI_PARTITION=y
Location:
-> Enable the block layer
-> Partition Types
[*] Advanced partition selection
...
[*] EFI GUID Partition support
## CONFIG_EFI=y
## CONFIG_EFI_STUB=y
Location:
-> Processor type and features
[*] EFI runtime service support
[*] EFI stub support
## CONFIG_FB_EFI=y
Location:
-> Device Drivers
-> Graphics support
-> Frame buffer Devices
[*] EFI-based Framebuffer Support
## CONFIG_FRAMEBUFFER_CONSOLE=y
Location:
-> Device Drivers
-> Graphics support
-> Console display driver support
Framebuffer Console support (Not available on mine)
## CONFIG_EFI_VARS is not set
## CONFIG_EFI_RUNTIME_MAP=y
Location:
-> Firmware Drivers
-> EFI (Extensible Firmware Interface) Support
< > EFI Variable Support via sysfs
[*] Export efi runtime maps to sysfs
## CONFIG_EFIVAR_FS=y
Location:
-> File systems
-> Pseudo filesystems
[*] EFI Variable filesystem
Note:
The only Kernel Config setting that a 'make defconfig' didn't set on
the UEFI-enabled host was this one:
## CONFIG_EFI_STUB=y
and without that setting in the kernel, attempts to boot the LFS system
tell you that:
Kernel doesn't support EFI handover
however, adding just that one Kernel Config setting sees you able to
boot into the LFS system using the host system's Grub.
USING GRUB TO SET UP THE BOOT PROCESS
INSTALLING GRUB TO THE EFI PARTITION
Installing GRUB to the EFI partition and creating an OS Boot Manager
entry is the major difference between the recipes in this hint and the
procedures in the LFS book. In concept, it is not actually a divergence
from the concepts of the book. The instructions there install GRUB to
the MBR, the MBR protected layer of a GPT disk or to a dedicated /boot
partition. The recipes here install GRUB to the EFI partition and
generate an entry in the system's Boot Manager. It is for the single
command here that this hint was written and for which all the non-LFS
packages were installed.
grub-install --target=x86_64-efi --efi-directory=/boot/efi \
--bootloader-id=LFS --recheck --debug
--efi-directory=<EFI Mount Point> not the actual EFI partition
--bootloader-id=<some name> is the directory on the EFI partition to
which the GRUB image is written.
Running this command generates lots of output. But at the end it will
indicate that it was successful. This command installs the GRUB image to
/boot/efi/EFI/LFS/grubx64.efi and creates the entry "LFS" in the system's
Boot Manager.
To check it, inspect the contents of /boot/efi/EFI/LFS and, as root, run
<efibootmgr>. The results of this command will list the Boot Order and
all the Boot Entries. If the entry "LFS" does not appear, read the
efibootmgr man page, create an entry and change the Boot Order to what is
desired.
CONFIGURING GRUB
Generate grub.cfg:
cat > /boot/grub/grub.cfg << "EOF"
# Begin /boot/grub/grub.cfg
set default=0
set timeout=5
insmod gzio
insmod part_gpt
insmod ext2
set root=(hd[x], gpt[y])
# hd[x] is the drive of the LFS partion and gpt[y] is the partition
insmod efi_gop
insmod efi_uga
insmod font
if loadfont /grub/unicode.pf2; then
loadfont /grub/unicode.pf2
set gfxmode=auto
insmod gfxterm
set gfxpayload=keep
terminal_output gfxterm
fi
menuentry "GNU/Linux, Linux <kernel name>" {
linux /boot/vmlinuz-<kernel name>; root=/dev/sda[x] ro
}
EOF
Note that in "menuentry" /dev/sda[x] is the device of the LFS partition.
FINAL DISCUSSION:
As stated before, the implementation of UEFI firmware and its manipulation
depends hugely on the manufacturer. As of the initial writing of this
hint, there is no standard approach. Therefore, while the recipes here all
do what is advertised, regrettably the system may not default to the grub
boot loader "out of the box." In that case, reviewing References 1-3, will
provide information that will lead users to a solution to the situation.
As always, one of the best resources is the {,B}LFS mailing lists.
At this point, it is worth stating that there are other helpfultools:
gummiboot and rEFInd are two of them. They are described as Boot Managers,
but in fact are a user space layer between the OS Boot Manager and the Boot
Loader. Information about both is in the references.
REFERENCES:
1. Rod's Books A collection of web page articles that goes into great
detail about the concepts of UEFI booting, partitioning and tools.
The below URL goes right to the efi information. www.rodsbooks.com is
the main page and has many, many good articles.
URL: http://www.rodsbooks.com/efi-bootloaders/index.html
2. "Unified Extensible Firmware Interface-ArchWiki"
URL: https://wiki.archlinux.org/index.php/
Unified_Extensible_Firmware_Interface
3. "GRUB-ArchWiki"
URL: https://wiki.archlinux.org/index.php/GRUB
4. Google
ACKNOWLEDGEMENTS:
* Craig Magee <lfs-support at lists.linuxfromscratch.org> for comments and testing
* Pierre Labastie <http://lists.linuxfromscratch.org/listinfo/lfs-dev> for testing,
font manipulation and comments.
TODO:
* Add paragraph and section numbers and TOC to make searchable
* Add appendix for migration from Legacy Boot to UEFI boot
* Add appendix for more options to default to GRUB
* Add appendix for LVM
* Add appendix for "standalone" GRUB on EFI partition independent
from distro
CHANGELOG:
[TBD]
* 2017-01-22
Updated for LFS 7.10 and "extra package" updates
dosfstools-3.0.26 -> dosfstools-3.0.28
efivar-0.12 -> efivar-30
efibootmgr-0.9.0 -> efibootmgr-14
unifont-7.0.05 -> unifont-9.0.06
[TBD]
* 2014-10-16
Initial hint.