I have the same problem. 3 node cluster working day after a reboot, and outputs the same mistakes.
INFO: task pveproxy:22867 blocked for more than 120 seconds.
[71520.042250] Tainted: G O 4.2.8-1-pve #1
[71520.042275] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message...
