[<0>] synchronize_rcu_expedited_wait_once+0x7f/0x1e0
[<0>] synchronize_rcu_expedited_wait+0x34/0x360
[<0>] rcu_exp_wait_wake+0x13/0x1f0
[<0>] kthread_worker_fn+0xae/0x260
[<0>] kthread+0x125/0x240
[<0>] ret_from_fork+0x2b/0x50
