Kernel update script for Pop!_OS

update-kernel.py

#!/usr/bin/python3
"""Script to copy initrd.img and vmlinuz.efi from /boot/ to /boot/efi where
systemd-boot looks for them.
"""


import glob
import os
import shutil
import sys

INITRD_GLOB = "/boot/initrd.img-*"
VMLINUZ_GLOB = "/boot/vmlinuz-*"
EFI_INITRD_PATH = "/boot/efi/EFI/Pop_OS-mainline/initrd.img"
EFI_VMLINUZ_PATH = "/boot/efi/EFI/Pop_OS-mainline/vmlinuz.efi"

def find_newest(l):
    newest = (0, 0, 0)
    newest_path = ""
    for entry in l:
        version = tuple(map(int, entry.split("-")[1].split(".")))
        if version > newest:
            newest = version
            newest_path = entry
    return newest, newest_path

if os.getuid() != 0:
    print("Error: need root permissions!")
    sys.exit(1)

initrds = glob.glob(INITRD_GLOB)
vmlinuzs = glob.glob(VMLINUZ_GLOB)

if len(initrds) != len(vmlinuzs):
    print("Error: different number of initrd.img and vmlinuz found!")
    sys.exit(1)
    
print(f"Found {len(initrds)} kernel versions.")
vi, pi = find_newest(initrds)
vv, pv = find_newest(vmlinuzs)
if vi != vv:
    print(f"Error: Newest initrd.img version ({vi}) does not match vmlinuz version ({vv})!")
    sys.exit(1)
print(f"Newest kernel version: {'.'.join(map(str, vi))}")

print(f"Copying {pi} -> {EFI_INITRD_PATH}...")
shutil.copyfile(pi, EFI_INITRD_PATH)
print(f"Copying {pv} -> {EFI_VMLINUZ_PATH}...")
shutil.copyfile(pv, EFI_VMLINUZ_PATH)
print("Done.")