[  841.790744] INFO: task btrfs-transacti:14104 blocked for more than 120 seconds.
[  841.790760]       Not tainted 3.13.0-32-generic #57-Ubuntu
[  841.790770] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  841.790786] btrfs-transacti D ffff88046fd34440     0 14104      2 0x00000000
[  841.790789]  ffff880852ed3e10 0000000000000002 ffff880866c097f0 ffff880852ed3fd8
[  841.790793]  0000000000014440 0000000000014440 ffff880866c097f0 ffff88044ce3e000
[  841.790796]  ffff880867c0b000 ffff880852ed3e30 ffff880851840000 ffff880851840070
[  841.790799] Call Trace:
[  841.790808]  [<ffffffff817200d9>] schedule+0x29/0x70
[  841.790831]  [<ffffffffa01a599d>] btrfs_commit_transaction+0x24d/0x970 [btrfs]
[  841.790835]  [<ffffffff810aaf00>] ? prepare_to_wait_event+0x100/0x100
[  841.790845]  [<ffffffffa01a1855>] transaction_kthread+0x1b5/0x240 [btrfs]
[  841.790854]  [<ffffffffa01a16a0>] ? btrfs_cleanup_transaction+0x550/0x550 [btrfs]
[  841.790857]  [<ffffffff8108b3d2>] kthread+0xd2/0xf0
[  841.790860]  [<ffffffff8108b300>] ? kthread_create_on_node+0x1d0/0x1d0
[  841.790864]  [<ffffffff8172c5bc>] ret_from_fork+0x7c/0xb0
[  841.790866]  [<ffffffff8108b300>] ? kthread_create_on_node+0x1d0/0x1d0