Crash with zfs upgrade -a

[Simon Walton]

The system has a ZFS root drive. I upgraded from 8.3 (amd64) to
10.1. Everything went smoothly but zpool/zfs upgrade recommended
upgrading the root drive. Zpool upgrade -a worked fine but
zfs upgrade -a caused the system to freeze for a few seconds
then reboot. There was no panic or crash log.

   The system still boots fine but the filesystems report as version 1.
Should I attempt to upgrade them again?

Thanks,
Simon