[<ffffffff8101b814>] save_stack_trace_tsk+0x24/0x50
[<ffffffff81207444>] proc_pid_stack+0xa4/0xf0
[<ffffffff8120a2f4>] proc_single_show+0x64/0xa0
[<ffffffff811bfde2>] seq_read+0xf2/0x400
[<ffffffff8119a585>] vfs_read+0xb5/0x1a0
[<ffffffff8119a8d1>] sys_read+0x51/0xb0
[<ffffffff8100b0d2>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff