[35040.204263] INFO: task btrfsck:17013 blocked for more than 120 seconds.
[35040.205889]       Not tainted 4.0.4-040004-generic #201505171336
[35040.207447] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[35040.209199] btrfsck         D ffff8803aa843ad8     0 17013   2285 0x00000002
[35040.209211]  ffff8803aa843ad8 0000000000000006 ffff8800bb92e180 ffff88042d2f0a00
[35040.209219]  ffff8804292f4600 ffff8803aa843ab8 ffff8803aa843fd8 7fffffffffffffff
[35040.209226]  7fffffffffffffff ffff8803aa843c70 0000000000000002 ffff8803aa843af8
[35040.209233] Call Trace:
[35040.209273]  [<ffffffff817ec827>] schedule+0x37/0x90
[35040.209288]  [<ffffffff817ef4d5>] schedule_timeout+0x1b5/0x210
[35040.209303]  [<ffffffff8105fb0e>] ? kvm_clock_read+0x1e/0x20
[35040.209310]  [<ffffffff8105fb0e>] ? kvm_clock_read+0x1e/0x20
[35040.209334]  [<ffffffff8105fb19>] ? kvm_clock_get_cycles+0x9/0x10
[35040.209365]  [<ffffffff810ec016>] ? ktime_get+0x46/0xb0
[35040.209374]  [<ffffffff817ebdca>] io_schedule_timeout+0xaa/0x130
[35040.209385]  [<ffffffff810bae70>] ? prepare_to_wait+0x60/0x90
[35040.209392]  [<ffffffff817ecf90>] ? out_of_line_wait_on_bit+0x90/0x90
[35040.209399]  [<ffffffff817ecfc6>] bit_wait_io+0x36/0x50
[35040.209405]  [<ffffffff817ece25>] __wait_on_bit+0x65/0x90
[35040.209416]  [<ffffffff8118429b>] ? find_get_pages_tag+0xcb/0x170
[35040.209424]  [<ffffffff81183857>] wait_on_page_bit+0xc7/0xd0
[35040.209435]  [<ffffffff810bb330>] ? wake_atomic_t_function+0x40/0x40
[35040.209444]  [<ffffffff81183a24>] filemap_fdatawait_range+0xf4/0x180
[35040.209454]  [<ffffffff81183adb>] filemap_fdatawait+0x2b/0x30
[35040.209476]  [<ffffffff811861b4>] filemap_write_and_wait+0x34/0x60
[35040.209535]  [<ffffffff812360c1>] __sync_blockdev+0x21/0x40
[35040.209546]  [<ffffffff812360f3>] sync_blockdev+0x13/0x20
[35040.209556]  [<ffffffff81236162>] __blkdev_put+0x62/0x210
[35040.209565]  [<ffffffff8123636b>] blkdev_put+0x5b/0x160
[35040.209575]  [<ffffffff81236495>] blkdev_close+0x25/0x30
[35040.209587]  [<ffffffff811fdf50>] __fput+0xc0/0x250
[35040.209598]  [<ffffffff811fe12e>] ____fput+0xe/0x10
[35040.209611]  [<ffffffff81096af4>] task_work_run+0xd4/0xf0
[35040.209620]  [<ffffffff8107bf43>] do_exit+0x1a3/0x480
[35040.209629]  [<ffffffff811fccf6>] ? vfs_write+0x196/0x1f0
[35040.209637]  [<ffffffff8107c2b4>] do_group_exit+0x44/0xa0
[35040.209645]  [<ffffffff8107c327>] SyS_exit_group+0x17/0x20
[35040.209657]  [<ffffffff817f098d>] system_call_fastpath+0x16/0x1b
[35040.209671] INFO: task blkid:29109 blocked for more than 120 seconds.
[35040.212711]       Not tainted 4.0.4-040004-generic #201505171336
[35040.213461] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[35040.213886] blkid           D ffff8801da81bac8     0 29109      1 0x00000004
[35040.213889]  ffff8801da81bac8 ffff88043fc58bf8 ffff8801c961e180 ffff88042d680000
[35040.213890]  ffff88042be1a800 ffff8801da81bb68 ffff8801da81bfd8 ffff88042be1a800
[35040.213892]  ffff88042ceb0d1c 00000000ffffffff ffff88042ceb0d20 ffff8801da81bae8
[35040.213894] Call Trace:
[35040.213897]  [<ffffffff817ec827>] schedule+0x37/0x90
[35040.213898]  [<ffffffff817ecaae>] schedule_preempt_disabled+0xe/0x10
[35040.213900]  [<ffffffff817ee715>] __mutex_lock_slowpath+0x95/0x110
[35040.213902]  [<ffffffff817ee7b3>] mutex_lock+0x23/0x37
[35040.213904]  [<ffffffff8123651b>] __blkdev_get+0x7b/0x430
[35040.213905]  [<ffffffff81236a90>] ? blkdev_get+0x1c0/0x1c0
[35040.213907]  [<ffffffff8123692e>] blkdev_get+0x5e/0x1c0
[35040.213908]  [<ffffffff81236a90>] ? blkdev_get+0x1c0/0x1c0
[35040.213910]  [<ffffffff81236aed>] blkdev_open+0x5d/0x80
[35040.213912]  [<ffffffff811f9f42>] do_dentry_open+0x262/0x380
[35040.213913]  [<ffffffff811fa0a9>] vfs_open+0x49/0x50
[35040.213916]  [<ffffffff8120abb0>] do_last+0x430/0x7e0
[35040.213918]  [<ffffffff8120afef>] path_openat+0x8f/0x480
[35040.213921]  [<ffffffff811b1d68>] ? __pte_alloc+0xd8/0x180
[35040.213922]  [<ffffffff811b0a70>] ? tlb_flush_mmu_free+0x40/0x60
[35040.213924]  [<ffffffff811b50ab>] ? __handle_mm_fault+0x1db/0x360
[35040.213926]  [<ffffffff8120d483>] do_filp_open+0x43/0xa0
[35040.213929]  [<ffffffff8121a03d>] ? __alloc_fd+0xcd/0x120
[35040.213931]  [<ffffffff811fb432>] do_sys_open+0x132/0x230
[35040.213932]  [<ffffffff811fb54e>] SyS_open+0x1e/0x20
[35040.213934]  [<ffffffff817f098d>] system_call_fastpath+0x16/0x1b