It's enough to downgrade udev before the "umount /mnt", everything else works with 215. Conversely, mkfs/mount with 208, upgrading to udev 215, and umount then hangs. stracing umount /mnt indeed hangs forever in the umount() call.
It's enough to downgrade udev before the "umount /mnt", everything else works with 215. Conversely, mkfs/mount with 208, upgrading to udev 215, and umount then hangs. stracing umount /mnt indeed hangs forever in the umount() call.