[torquedev] pbs_server hanging

[Douglas Holt]

I'm seeing numerous socket timeouts when trying to use commands that 
interact with pbs_server (ver. 4.1.1) and saw this in my logs:

INFO: task pbs_server:57675 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
pbs_server    D 0000000000000002     0 57675      1 0x00000080
  ffff880802ebdbb8 0000000000000086 0000000000000000 ffff88102c7ae3c8
  0000000000000000 ffff88102c7ae3e0 00000000000000c3 0000000000000001
  ffff8807e41ba5f8 ffff880802ebdfd8 000000000000f4e8 ffff8807e41ba5f8
Call Trace:
  [<ffffffff8105fa50>] ? default_wake_function+0x0/0x20
  [<ffffffff814ee0ae>] __mutex_lock_slowpath+0x13e/0x180
  [<ffffffff814edf4b>] mutex_lock+0x2b/0x50
  [<ffffffff814bc9d1>] unix_dgram_recvmsg+0x71/0x380
  [<ffffffff811458fd>] ? page_add_new_anon_rmap+0x9d/0xf0
  [<ffffffff8141bf51>] sock_aio_read+0x181/0x190
  [<ffffffff8117641a>] do_sync_read+0xfa/0x140
  [<ffffffff81090bf0>] ? autoremove_wake_function+0x0/0x40
  [<ffffffff8120c3c6>] ? security_file_permission+0x16/0x20
  [<ffffffff81176ee1>] vfs_read+0x181/0x1a0
  [<ffffffff810d46e2>] ? audit_syscall_entry+0x272/0x2a0
  [<ffffffff81176f51>] sys_read+0x51/0x90
  [<ffffffff8100b0f2>] system_call_fastpath+0x16/0x1b