Comment # 4 on bug 1015254 from Ulrich Windl

(Sorry for the delay)
Some clarification: It seems the problem is not the /home filesystem, but its
underlying physical volume, an encrypted partition created on MD-RAID-1. Also
the current OS does not cause a timeout, but it still fails.
So the Setup is like this: (two disks (IMSM)) -> MD-RAID-1 -> Partition #5 ->
Encryption -> PV for LVM -> LV for /home filesystem

>From what I can see is that the filesystem is unmounted, I'm unsure about the
VG being deactivated (my guess is NO). But it seems then the crypt -layer
cannot be deactivated, because LVM keeps it busy. For me it's not obvious from
the systemd journal, but here it is:

Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounting /run/user/1000...
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounting /home...
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounting /mnt...
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounting /opt/android...
Aug 25 16:50:53 i7g4x4a kernel: audit: type=1305 audit(1535208653.449:228):
audit_pid=0 old=1849 auid=4294967295 ses=4294967295 res=1
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounting /sys/kernel/debug/tracing...
Aug 25 16:50:53 i7g4x4a kernel: XFS (dm-8): Unmounting Filesystem
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounted /run/user/1000.
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounted /mnt.
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounted /sys/kernel/debug/tracing.
Aug 25 16:50:53 i7g4x4a kernel: XFS (dm-3): Unmounting Filesystem
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap /dev/mapper/system-swap.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap
/dev/disk/by-uuid/779aaf04-180c-4f89-9300-9a69fbf44c01.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap
/dev/disk/by-id/raid-system-swap.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap
/dev/disk/by-id/dm-uuid-LVM-3Ef9ozXfr2XuKX0fAt8atPyzlY40E7KzwTSuuBoqx3GB9AcW9oMmjeSmpzVx9Yox.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap
/dev/disk/by-id/dm-name-system-swap.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap /dev/dm-1.
Aug 25 16:50:53 i7g4x4a systemd[1]: Deactivated swap /dev/system/swap.
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounted /home.
Aug 25 16:50:53 i7g4x4a systemd[1]: Unmounted /opt/android.
Aug 25 16:50:53 i7g4x4a systemd[1]: Stopped File System Check on
/dev/system/android.
Aug 25 16:50:53 i7g4x4a systemd[1]: Stopped File System Check on
/dev/system/home.
Aug 25 16:50:53 i7g4x4a systemd[1]: Stopped target Local File Systems (Pre).
Aug 25 16:50:53 i7g4x4a systemd[1]: Stopped Remount Root and Kernel File
Systems.
Aug 25 16:50:53 i7g4x4a systemd[1]: Stopped Create Static Device Nodes in /dev.
Aug 25 16:50:53 i7g4x4a systemd[1]: Removed slice system-systemd\x2dfsck.slice.
Aug 25 16:50:57 i7g4x4a systemd[1]: Received SIGRTMIN+20 from PID 18675
(plymouthd).
Aug 25 16:50:58 i7g4x4a systemd-cryptsetup[18825]: Failed to deactivate: Device
or resource busy
Aug 25 16:50:58 i7g4x4a systemd[1]:
systemd-cryptsetup@cr_md\x2duuid\x2d2047fabb:aa594b5d:ff1519a1:7d0ff516\x2dpart5.service:
Control process exited, code=exite
Aug 25 16:50:58 i7g4x4a systemd[1]: Stopped Cryptography Setup for
cr_md-uuid-2047fabb:aa594b5d:ff1519a1:7d0ff516-part5.
Aug 25 16:50:58 i7g4x4a systemd[1]:
systemd-cryptsetup@cr_md\x2duuid\x2d2047fabb:aa594b5d:ff1519a1:7d0ff516\x2dpart5.service:
Unit entered failed state.
Aug 25 16:50:58 i7g4x4a systemd[1]:
systemd-cryptsetup@cr_md\x2duuid\x2d2047fabb:aa594b5d:ff1519a1:7d0ff516\x2dpart5.service:
Failed with result 'exit-code'.
Aug 25 16:50:58 i7g4x4a systemd[1]: Reached target Unmount All Filesystems.
Aug 25 16:50:58 i7g4x4a systemd[1]: Removed slice
system-systemd\x2dcryptsetup.slice.

Would you agree that systemd does not even try to deactivate the VG before
trying to deactivate the crypt layer?

Aug 25 16:50:58 i7g4x4a systemd[1]: Reached target Shutdown.
Aug 25 16:50:58 i7g4x4a systemd[1]: Starting /etc/init.d/halt.local
Compatibility...
Aug 25 16:50:58 i7g4x4a systemd[1]: Started /etc/init.d/halt.local
Compatibility.
Aug 25 16:50:58 i7g4x4a systemd[1]: Reached target Final Step.
Aug 25 16:50:58 i7g4x4a systemd[1]: Starting Power-Off...
Aug 25 16:50:58 i7g4x4a systemd[1]: Shutting down.
Aug 25 16:50:58 i7g4x4a systemd-shutdown[1]: Sending SIGTERM to remaining
processes...
Aug 25 16:50:58 i7g4x4a haveged[1031]: haveged: Stopping due to signal 15
Aug 25 16:50:58 i7g4x4a haveged[1031]: haveged starting up
Aug 25 16:50:58 i7g4x4a systemd-journald[1007]: Journal stopped
-- Reboot --