grub_install_with_uefi

#1 General info

The installation of GRUB on a UEFI platform requires that the EFI Variable file system
The efivar package provides tools and libraries to manipulate EFI variables.


#2 Fix an error

/usr/include/linux/mount.h:95:6: error: redeclaration of 'enum fsconfig_command'

##1 create a file named fs_flag.h with necessary definitions copyed from linux header files

##2 modify efivarfs.c

/* #include <linux/fs.h> */
#include <sys/mount.h>
#include "fs_flag.h"


<linux/fs.h> conflicts with <sys/mount.h>
this is a known issue see https://github.com/rhboot/efivar/issues/227



# grub_install


mkdir -pv /boot/efi &&
mount -v -t vfat /dev/sda4 /boot/efi

## add an entry

cat >> /etc/fstab << EOF
/dev/sda4 /boot/efi vfat defaults 0 1
EOF

grub-install --bootloader-id=lfs --recheck



#3 Directly editing grub.cfg makes multiboot possible


cat > /boot/grub/grub.cfg << EOF
# Begin /boot/grub/grub.cfg
set default=0
set timeout=5

insmod part_gpt
insmod ext2
set root=(hd0,5)

if loadfont /boot/grub/fonts/unicode.pf2; then
  set gfxmode=auto
  insmod all_video
  terminal_output gfxterm
fi

menuentry "GNU/Linux, Linux 5.19.2-lfs-11.2"  {
  linux   /boot/vmlinuz-5.19.2-lfs-11.2 root=/dev/sda5 ro
}

EOF


#4 Disk repartition may make system unbootable, a bootable usb is useful for editing /etc/fstab

#5 To do read grub documentation