This bug was fixed in the package zfs-linux - 0.6.5.6-0ubuntu25
--------------- zfs-linux (0.6.5.6-0ubuntu25) xenial; urgency=medium
* Fix zpl_mount() deadlock (LP: #1781364) - Upstream ZFS fix ac09630d8b0b ("Fix zpl_mount() deadlock") fixes deadlock on multiple parallelized mount/umounts
-- Colin Ian King <email address hidden> Thu, 12 Jul 2018 09:18:24 +0100
This bug was fixed in the package zfs-linux - 0.6.5.6-0ubuntu25
---------------
zfs-linux (0.6.5.6-0ubuntu25) xenial; urgency=medium
* Fix zpl_mount() deadlock (LP: #1781364)
- Upstream ZFS fix ac09630d8b0b ("Fix zpl_mount() deadlock")
fixes deadlock on multiple parallelized mount/umounts
-- Colin Ian King <email address hidden> Thu, 12 Jul 2018 09:18:24 +0100