INFO: task reboot:4476 blocked for more than 120 seconds.

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

Kernel panic - not syncing: hung_task: blocked tasks

Call Trace:

 [<ffffffff81979ce9>] dump_stack+0x19/0x1b

 [<ffffffff819626f9>] panic+0xc8/0x1cc

 [<ffffffff819666de>] watchdog.cold.0+0x60/0x60

 [<ffffffff810e4880>] ? hung_task_panic+0x20/0x20

 [<ffffffff8108ff40>] kthread+0xc0/0xd0

 [<ffffffff8108fe80>] ? kthread_worker_fn+0x170/0x170

 [<ffffffff819afb2c>] ret_from_fork+0x7c/0xb0

 [<ffffffff8108fe80>] ? kthread_worker_fn+0x170/0x170