Comment 54 for bug 585657

same lockups when copying / rsync 200MB files TO FreeNas NFS server, didn't have problems reading.

Gigabyte Brix using Asix ax88179_178a Gigabit USB3 nic, tried a second nic with same result.

Kernel: 3.17.4-031704-generic (mainline)

Xubuntu Trusty 14.0.1

ii nfs-kernel-server 1:1.2.8-6ubuntu1.1
ii nfs-common 1:1.2.8-6ubuntu1.1

22699-Jan 14 14:08:44 brix kernel: [ 360.548908] INFO: task cp:5165 blocked for more than 120 seconds.
22700-Jan 14 14:08:44 brix kernel: [ 360.548912] Tainted: G OE 3.17.4-031704-generic #201411211317
22701:Jan 14 14:08:44 brix kernel: [ 360.548913] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
22702-Jan 14 14:08:44 brix kernel: [ 360.548914] cp D 0000000000000007 0 5165 1 0x00000004
22703-Jan 14 14:08:44 brix kernel: [ 360.548917] ffff8801eb9b7c88 0000000000000086 ffff8801eb9b7c28 ffffffff8101e5c9
22704-Jan 14 14:08:44 brix kernel: [ 360.548919] ffff8801eb9b7fd8 00000000000145c0 ffff8800bbeee200 00000000000145c0
22705-Jan 14 14:08:44 brix kernel: [ 360.548920] ffff880213235000 ffff88003643e400 ffff8801eb9b7c88 ffff88021ebd4ec0
22706-Jan 14 14:08:44 brix kernel: [ 360.548922] Call Trace:
22707-Jan 14 14:08:44 brix kernel: [ 360.548928] [<ffffffff8101e5c9>] ? read_tsc+0x9/0x10
22708-Jan 14 14:08:44 brix kernel: [ 360.548932] [<ffffffff817a2970>] ? bit_wait+0x50/0x50
22709-Jan 14 14:08:44 brix kernel: [ 360.548933] [<ffffffff817a20c9>] schedule+0x29/0x70
22710-Jan 14 14:08:44 brix kernel: [ 360.548935] [<ffffffff817a219f>] io_schedule+0x8f/0xd0
22711-Jan 14 14:08:44 brix kernel: [ 360.548937] [<ffffffff817a299b>] bit_wait_io+0x2b/0x50
22712-Jan 14 14:08:44 brix kernel: [ 360.548939] [<ffffffff817a2865>] __wait_on_bit+0x65/0x90
22713-Jan 14 14:08:44 brix kernel: [ 360.548942] [<ffffffff811731eb>] ? find_get_pages_tag+0xcb/0x170
22714-Jan 14 14:08:44 brix kernel: [ 360.548944] [<ffffffff81172637>] wait_on_page_bit+0xc7/0xd0
22715-Jan 14 14:08:44 brix kernel: [ 360.548947] [<ffffffff810b3fd0>] ? wake_atomic_t_function+0x40/0x40
22716-Jan 14 14:08:44 brix kernel: [ 360.548949] [<ffffffff81172804>] filemap_fdatawait_range+0xf4/0x180
22717-Jan 14 14:08:44 brix kernel: [ 360.548951] [<ffffffff811747fd>] filemap_write_and_wait_range+0x4d/0x80
22718-Jan 14 14:08:44 brix kernel: [ 360.548969] [<ffffffffc01f9223>] nfs_file_fsync+0x53/0x150 [nfs]
22719-Jan 14 14:08:44 brix kernel: [ 360.548974] [<ffffffff81219899>] vfs_fsync+0x29/0x40
22720-Jan 14 14:08:44 brix kernel: [ 360.548980] [<ffffffffc01f9cfa>] nfs_file_flush+0x8a/0xd0 [nfs]
22721-Jan 14 14:08:44 brix kernel: [ 360.548982] [<ffffffff811e743a>] filp_close+0x3a/0x90
22722-Jan 14 14:08:44 brix kernel: [ 360.548984] [<ffffffff8120709f>] __close_fd+0x8f/0xc0
22723-Jan 14 14:08:44 brix kernel: [ 360.548986] [<ffffffff811e8cd3>] SyS_close+0x23/0x50
22724-Jan 14 14:08:44 brix kernel: [ 360.548988] [<ffffffff817a656d>] system_call_fastpath+0x1a/0x1f

After reading: http://art.ubuntuforums.org/showthread.php?t=1478413 this is REALLY embarrassing.