Update grub
From Karmaking
/etc/default/grub /boot/grub/grub.cfg
mount -t proc proc $MY_CHROOT/proc mount -o bind /dev $MY_CHROOT/dev mount -t sysfs sysfs $MY_CHROOT/sys
chroot
grub-mkdevicemap update-grub2
/etc/default/grub /boot/grub/grub.cfg
mount -t proc proc $MY_CHROOT/proc mount -o bind /dev $MY_CHROOT/dev mount -t sysfs sysfs $MY_CHROOT/sys
chroot
grub-mkdevicemap update-grub2