Since we fixed core trouble with sequence of
suspend/resume/suspend without udev wait
we can drop 'should' and expect volume is still mounted.
# Switch to 'writethrough' - this should be supported
lvchange --cachemode writethrough $vg/$lv1
-# FIXME
-# systemd on fc23 'strikes-in' and unmounts mnt
-# ATM the reason is unclear (bug in systemd, bad udev rules?)
-# as a workaround mount again and 'WARN' test
-should not mount "$DM_DEV_DIR/$vg/$lv1" mnt
+# Check $lv1 remains mounted (so it's not been unmounted by systemd)
+not mount "$DM_DEV_DIR/$vg/$lv1" mnt
lvconvert --thin $vg/$lv1 --originname extorg --thinpool $vg/tpool