Comment 53 for bug 585657

Same problem with Ubuntu Trusty "Ubuntu 14.04.1 LTS" / kernel 3.13.0-32-generic.
Both NFS client and server run this version of Ubuntu and kernel version. Trying to transfer 500GB files from mdadm raid5 to NFS using lbzip2:

[48693.533918] INFO: task lbzip2:14344 blocked for more than 120 seconds.
[48693.536784] Not tainted 3.13.0-32-generic #57-Ubuntu
[48693.539750] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[48693.542764] lbzip2 D ffff88011fc94440 0 14344 14341 0x00000000
[48693.542773] ffff8800d235bb38 0000000000000002 ffff8801194497f0 ffff8800d235bfd8
[48693.542782] 0000000000014440 0000000000014440 ffff8801194497f0 ffff88011fc94cd8
[48693.542789] ffff88011ffd3f28 0000000000000002 ffffffffa0219fe0 ffff8800d235bbb0
[48693.542795] Call Trace:
[48693.542838] [<ffffffffa0219fe0>] ? nfs_free_request+0xb0/0xb0 [nfs]
[48693.542851] [<ffffffff817203fd>] io_schedule+0x9d/0x140
[48693.542877] [<ffffffffa0219fee>] nfs_wait_bit_uninterruptible+0xe/0x20 [nfs]
[48693.542884] [<ffffffff81720882>] __wait_on_bit+0x62/0x90
[48693.542908] [<ffffffffa0219fe0>] ? nfs_free_request+0xb0/0xb0 [nfs]
[48693.542917] [<ffffffff81720927>] out_of_line_wait_on_bit+0x77/0x90
[48693.542926] [<ffffffff810aaf40>] ? autoremove_wake_function+0x40/0x40
[48693.542948] [<ffffffffa021a383>] nfs_wait_on_request+0x33/0x40 [nfs]
[48693.542971] [<ffffffffa021f2d0>] nfs_updatepage+0x150/0x650 [nfs]
[48693.542991] [<ffffffffa021096b>] nfs_write_end+0x5b/0x340 [nfs]
[48693.543000] [<ffffffff8114e616>] generic_file_buffered_write+0x156/0x250
[48693.543009] [<ffffffff8114fc81>] __generic_file_aio_write+0x1c1/0x3d0
[48693.543016] [<ffffffff8114fee8>] generic_file_aio_write+0x58/0xa0
[48693.543036] [<ffffffffa020fbdb>] nfs_file_write+0xbb/0x1d0 [nfs]
[48693.543043] [<ffffffff811bc3da>] do_sync_write+0x5a/0x90
[48693.543050] [<ffffffff811bcb64>] vfs_write+0xb4/0x1f0
[48693.543056] [<ffffffff811bd599>] SyS_write+0x49/0xa0
[48693.543063] [<ffffffff8172c87f>] tracesys+0xe1/0xe6

NFS client hardware Dell T605 server, NFS server HP Proliant ML150 G2