[<0>] __flush_workqueue+0x139/0x400
[<0>] xlog_cil_push_now.isra.0+0x5e/0xa0 [xfs]
[<0>] xlog_cil_force_seq+0x7e/0x250 [xfs]
[<0>] xfs_log_force_seq+0x72/0x160 [xfs]
[<0>] xfs_file_fsync+0x1ac/0x1e0 [xfs]
[<0>] loop_process_work+0x299/0x3d0 [loop]
[<0>] process_one_work+0x196/0x3c0
[<0>] worker_thread+0x281/0x3a0
[<0>] kthread+0x104/0x110
[<0>] ret_from_fork+0x2b/0x50
