util-linux 2.39 switched to the new mount API using fsconfig.
Unfortunately, this breaks remounting of FUSE and overlayfs mounts as it
tries to re-set existing mount options which those filesystems do not
allow. See [1] and [2] for upstream bug reports.
Unfortunately, ceph-fuse relies on remounting to trim kernel dcache
entries. It checks for this at mount time, so ceph-fuse mounting fails
with 2.39.
[1] https://github.com/util-linux/util-linux/issues/2528
[2] https://github.com/util-linux/util-linux/issues/2576