This is a somewhat harmless issue which seems to be common on live cd's including Fedora's according to the issue below. On shutdown you will see the following, although it does not block anything:
[ 27.963208] systemd-shutdown[1]: Could not detach loopback /dev/loop0: Device or resource busy
[ 27.968809] systemd-shutdown[1]: Failed to finalize loop devices, ignoring.
[ 27.971444] reboot: Power down
Preferably, we would umount the overlayfs and the erofs after systemd switches to rootfs. So on completion of boot /dev/loop0 and it's mounts are detached and unmounted, since they are no longer necessary.
Reading the below issue might yield some ideas of how to cleanly solve this:
This is a somewhat harmless issue which seems to be common on live cd's including Fedora's according to the issue below. On shutdown you will see the following, although it does not block anything:
Preferably, we would umount the overlayfs and the erofs after systemd switches to rootfs. So on completion of boot /dev/loop0 and it's mounts are detached and unmounted, since they are no longer necessary.
Reading the below issue might yield some ideas of how to cleanly solve this:
systemd/systemd#17988