[Pkg-raspi-maintainers] Bug#979977: raspi-firmware: Seems to ignore latest installed kernel (5.10.0-1-armmp-lpae) while the booting kernel is older (5.10.0-trunk-armmp-lpae)

[Gunnar Wolf]

tags 979977 + confirmed
thanks

Ummh, interesting...

Latest kernel and initrd are found by the following simplistic,
lexicographic logic:

    latest_kernel=$(ls -1 /boot/vmlinuz-* | grep -v '\.dpkg-bak$' | sort -V -r | head -1)
    if [ -z "$latest_kernel" ]; then
      echo "raspi-firmware: no kernel found in /boot/vmlinuz-*, cannot populate /boot/firmware"
      exit 0
    fi
    
    latest_initrd=$(ls -1 /boot/initrd.img-* | grep -v '\.dpkg-bak$' | sort -V -r | head -1)
    if [ -z "$latest_initrd" ]; then
      echo "raspi-firmware: no initrd found in /boot/initrd.img-*, cannot populate /boot/firmware"
      exit 0
    fi

So... Yes, it behaves as you report. Modifying the logic to search in
/tmp/boot:

    $ touch /tmp/boot/vmlinuz-{5.10.0-trunk-armmp-lpae,5.10.0-1-armmp-lpae}
    $ latest_kernel=$(ls -1 /tmp/boot/vmlinuz-* | grep -v '\.dpkg-bak$' | sort -V -r | head -1)
    $ echo $latest_kernel
    /tmp/boot/vmlinuz-5.10.0-trunk-armmp-lpae

Now... What to do here? I think dpkg --compare-versions here agreees
with the simplistic ordering set by ls:

     $ if dpkg --compare-versions 5.10.0-trunk-armmp-lpae gt 5.10.0-1-armmp-lpae
     then
	echo trunk is larger
     else
        echo 1 is larger
     fi
     trunk is larger

How would you suggest to check for this?