There are 252 (42 * 6) lines of device-mapper's error messages in the Neil's
log.
Dracut tries 42 times and gives up:
_cnt=0
while [ $_cnt -le 40 ]; do
_check_shutdown && break
_cnt=$(($_cnt+1))
done
[ $_cnt -ge 40 ] && _check_shutdown final
https://github.com/dracutdevs/dracut/blob/master/modules.d/99shutdown/shutdown.sh