Comment 8 for bug 1832859

yeah I think I found the issue in your log.
Consider [1] again and look at
  /lib/systemd/system/blk-availability.service

This is what calls blkdeactivate on shutdown.

It only has a
  WantedBy=sysinit.target
But no ordering Before anything.
It even has
  DefaultDependencies=no
which will make it start early only waiting for the listed
After=lvm2-activation.service lvm2-lvmetad.service iscsi-shutdown.service iscsi.service iscsid.service fcoe.service

But in reverse that also means it has to wait on NOTHING to start "stopping" which is the call to blkdeactivate.

IMHO that is a bug in lvm2, that should ensure that this probably should be ordered
somewhere:
- closely after local-fs.target (on shutdown); I mean FS should be gone before deactivating devices right?
- the startup ordering isn't important as it is calling just /bin/true

My (uneducated) suggestion would be to add
  Before=local-fs.target
to
 /lib/systemd/system/blk-availability.service
Then run
 $ systemctl daemon-reload

(maybe needs another reboot then, not sure).
From there I'd assume that the shutdown ordering (beig the inverse) would order it AFTER local-fs which IMHO is what we'd want.

Please give this a try and I'll add an LVM task here.

[1]: https://www.freedesktop.org/software/systemd/man/bootup.html