I have an s3fs-fuse "device" mounted at
/mnt/s3. I want to unmount it so that I can remount it with the
mp_umask flag so that
chroot will work properly.
The command should be:
fusermount -u /mnt/s3
Unfortunately the result is:
fusermount: failed to unmount /mnt/s3: Device or resource busy
That's not helpful. Shouldn't be this hard!