Comment 4 for bug 1310551

I have the same issue here. It only happens when using the NVidia display driver.

I get this in Kern.log when it happens:
Jun 7 00:17:48 laptop kernel: [ 480.797985] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jun 7 00:17:48 laptop kernel: [ 480.799932] fsnotify_mark D ffff88022eed4440 0 80 2 0x00000000
Jun 7 00:17:48 laptop kernel: [ 480.799940] ffff88021ee49ce0 0000000000000002 ffff88021edf5fc0 ffff88021ee49fd8
Jun 7 00:17:48 laptop kernel: [ 480.799952] 0000000000014440 0000000000014440 ffff88021edf5fc0 ffff88021ee49e10
Jun 7 00:17:48 laptop kernel: [ 480.799964] ffff88021ee49e18 7fffffffffffffff ffff88021edf5fc0 0000000000000000
Jun 7 00:17:48 laptop kernel: [ 480.799970] Call Trace:
Jun 7 00:17:48 laptop kernel: [ 480.799983] [<ffffffff8171e639>] schedule+0x29/0x70
Jun 7 00:17:48 laptop kernel: [ 480.799988] [<ffffffff8171d889>] schedule_timeout+0x239/0x2d0
Jun 7 00:17:48 laptop kernel: [ 480.799996] [<ffffffff81075e8b>] ? mod_timer+0x13b/0x210
Jun 7 00:17:48 laptop kernel: [ 480.800001] [<ffffffff81075f78>] ? add_timer+0x18/0x20
Jun 7 00:17:48 laptop kernel: [ 480.800007] [<ffffffff8171f156>] wait_for_completion+0xa6/0x160
Jun 7 00:17:48 laptop kernel: [ 480.800014] [<ffffffff8109a7a0>] ? wake_up_state+0x20/0x20
Jun 7 00:17:48 laptop kernel: [ 480.800022] [<ffffffff810c67de>] __synchronize_srcu+0xfe/0x180
Jun 7 00:17:48 laptop kernel: [ 480.800028] [<ffffffff810c62f0>] ? call_srcu+0x70/0x70
Jun 7 00:17:48 laptop kernel: [ 480.800052] [<ffffffff810c687d>] synchronize_srcu+0x1d/0x20
Jun 7 00:17:48 laptop kernel: [ 480.800067] [<ffffffff811ff7f7>] fsnotify_mark_destroy+0x87/0x150
Jun 7 00:17:48 laptop kernel: [ 480.800075] [<ffffffff810aaea0>] ? prepare_to_wait_event+0x100/0x100
Jun 7 00:17:48 laptop kernel: [ 480.800081] [<ffffffff811ff770>] ? fsnotify_put_mark+0x40/0x40
Jun 7 00:17:48 laptop kernel: [ 480.800087] [<ffffffff8108b322>] kthread+0xd2/0xf0
Jun 7 00:17:48 laptop kernel: [ 480.800100] [<ffffffff8108b250>] ? kthread_create_on_node+0x1d0/0x1d0
Jun 7 00:17:48 laptop kernel: [ 480.800107] [<ffffffff8172ab3c>] ret_from_fork+0x7c/0xb0
Jun 7 00:17:48 laptop kernel: [ 480.800117] [<ffffffff8108b250>] ? kthread_create_on_node+0x1d0/0x1d0
Jun 7 00:17:48 laptop kernel: [ 480.800172] INFO: task kio_trash:3826 blocked for more than 120 seconds.
Jun 7 00:17:48 laptop kernel: [ 480.801999] Tainted: PF O 3.13.0-29-generic #53-Ubuntu
Jun 7 00:17:48 laptop kernel: [ 480.803729] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jun 7 00:17:48 laptop kernel: [ 480.805470] kio_trash D ffff88022efd4440 0 3826 3569 0x00000002
Jun 7 00:17:48 laptop kernel: [ 480.805475] ffff880222fb3c80 0000000000000002 ffff88021e2947d0 ffff880222fb3fd8
Jun 7 00:17:48 laptop kernel: [ 480.805481] 0000000000014440 0000000000014440 ffff88021e2947d0 ffff880222fb3db0
Jun 7 00:17:48 laptop kernel: [ 480.805486] ffff880222fb3db8 7fffffffffffffff ffff88021e2947d0 ffff8802239cc160
Jun 7 00:17:48 laptop kernel: [ 480.805491] Call Trace:
Jun 7 00:17:48 laptop kernel: [ 480.805497] [<ffffffff8171e639>] schedule+0x29/0x70
Jun 7 00:17:48 laptop kernel: [ 480.805502] [<ffffffff8171d889>] schedule_timeout+0x239/0x2d0
Jun 7 00:17:48 laptop kernel: [ 480.805508] [<ffffffff810aaa44>] ? __wake_up+0x44/0x50
Jun 7 00:17:48 laptop kernel: [ 480.805515] [<ffffffff81201741>] ? inotify_remove_from_idr+0xa1/0x1f0
Jun 7 00:17:48 laptop kernel: [ 480.805521] [<ffffffff8171f156>] wait_for_completion+0xa6/0x160
Jun 7 00:17:48 laptop kernel: [ 480.805527] [<ffffffff8109a7a0>] ? wake_up_state+0x20/0x20
Jun 7 00:17:48 laptop kernel: [ 480.805533] [<ffffffff810c67de>] __synchronize_srcu+0xfe/0x180
Jun 7 00:17:48 laptop kernel: [ 480.805538] [<ffffffff810c62f0>] ? call_srcu+0x70/0x70
Jun 7 00:17:48 laptop kernel: [ 480.805544] [<ffffffff810c687d>] synchronize_srcu+0x1d/0x20
Jun 7 00:17:48 laptop kernel: [ 480.805549] [<ffffffff811fefae>] fsnotify_destroy_group+0x1e/0x40
Jun 7 00:17:48 laptop kernel: [ 480.805555] [<ffffffff81201032>] inotify_release+0x22/0x50
Jun 7 00:17:48 laptop kernel: [ 480.805562] [<ffffffff811be384>] __fput+0xe4/0x260
Jun 7 00:17:48 laptop kernel: [ 480.805567] [<ffffffff811be54e>] ____fput+0xe/0x10
Jun 7 00:17:48 laptop kernel: [ 480.805575] [<ffffffff810880c4>] task_work_run+0xc4/0xe0
Jun 7 00:17:48 laptop kernel: [ 480.805580] [<ffffffff81069c08>] do_exit+0x2b8/0xa50
Jun 7 00:17:48 laptop kernel: [ 480.805586] [<ffffffff8109a790>] ? wake_up_state+0x10/0x20
Jun 7 00:17:48 laptop kernel: [ 480.805591] [<ffffffff81077b4e>] ? signal_wake_up_state+0x1e/0x30
Jun 7 00:17:48 laptop kernel: [ 480.805597] [<ffffffff81078eb2>] ? zap_other_threads+0x82/0xa0
Jun 7 00:17:48 laptop kernel: [ 480.805601] [<ffffffff8106a41f>] do_group_exit+0x3f/0xa0
Jun 7 00:17:48 laptop kernel: [ 480.805606] [<ffffffff8106a494>] SyS_exit_group+0x14/0x20
Jun 7 00:17:48 laptop kernel: [ 480.805612] [<ffffffff8172adff>] tracesys+0xe1/0xe6
Jun 7 00:17:48 laptop kernel: [ 480.805618] INFO: task kio_trash:4195 blocked for more than 120 seconds.
Jun 7 00:17:48 laptop kernel: [ 480.807360] Tainted: PF O 3.13.0-29-generic #53-Ubuntu
Jun 7 00:17:48 laptop kernel: [ 480.809084] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
Jun 7 00:17:48 laptop kernel: [ 480.810826] kio_trash D ffff88022ee14440 0 4195 3569 0x00000002
Jun 7 00:17:48 laptop kernel: [ 480.810831] ffff8801f879dc80 0000000000000002 ffff880223358000 ffff8801f879dfd8
Jun 7 00:17:48 laptop kernel: [ 480.810836] 0000000000014440 0000000000014440 ffff880223358000 ffff8801f879ddb0
Jun 7 00:17:48 laptop kernel: [ 480.810841] ffff8801f879ddb8 7fffffffffffffff ffff880223358000 ffff8802239cc160
Jun 7 00:17:48 laptop kernel: [ 480.810846] Call Trace: