System went to hung state while shutting down the system

Issue

• INIT 6 was issued, but the server never went down. Hence, the system dump was forced.
• vmcore shows the below before the forced crash

INFO: task java:55117 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
java          D 0000000000000011     0 55117  51274 0x00000000
 ffff8848e0735d20 0000000000000082 0000000000000000 ffff884800000000
 ffffffff8118f795 ffff8829a8991063 ffff8848e0735dd8 ffff8848e0735d58
 ffff8850ce03a638 ffff8848e0735fd8 000000000000fb88 ffff8850ce03a638
Call Trace:
 [<ffffffff8118f795>] ? path_to_nameidata+0x25/0x60
 [<ffffffff8150f8f5>] schedule_timeout+0x215/0x2e0
 [<ffffffff812777e9>] ? cpumask_next_and+0x29/0x50
 [<ffffffff81065c75>] ? enqueue_entity+0x125/0x410
 [<ffffffff8150f573>] wait_for_common+0x123/0x180
 [<ffffffff81063990>] ? default_wake_function+0x0/0x20
 [<ffffffff8150f68d>] wait_for_completion+0x1d/0x20
 [<ffffffff8106d549>] do_fork+0x1d9/0x480
 [<ffffffff8119fa22>] ? alloc_fd+0x92/0x160
 [<ffffffff8118b7f5>] ? do_pipe_flags+0xd5/0x140
 [<ffffffff81014115>] sys_vfork+0x25/0x30
 [<ffffffff8100b3d3>] stub_vfork+0x13/0x20
 [<ffffffff8100b072>] ? system_call_fastpath+0x16/0x1b
SysRq : Trigger a crash
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff8133de16>] sysrq_handle_crash+0x16/0x20