# mount /dev/sda3/mnt
# mount /dev/sda1/mnt/boot/efi
# for i in /dev /dev/pts /proc /sys; do mount -B $i /mnt$i; done
# cp /etc/resolv.conf /mnt/etc
# modprobe efivars
# chroot /mnt /bin/bash

# for i in /sys /proc /dev/pts /dev; do umount /mnt$i; done
# umount /mnt/boot/efi
# umount /mnt
# reboot