IJ06142: NFSV3 FILE LOCK MAY NOT BE RELEASED WHEN THE PROCESS TERMINATES

APAR status

• Closed as program error.

Error description

• NFSv3 file lock may not be released even if the process
  holding the lock is
  terminated. The subsequent lock request by another
  process will fail. The new
  process needs to wait for the lock to released however
  the lock is not held
  by any process. This may result in a hang like situation.
  
  The stack trace for the process :
  
  pvthread+085800 STACK:
  [0010A830]e_block_thread+000290 ()
  [00014F50].kernel_add_gate_cstack+000030 ()
  [05F3EB50]rtcm_recv+000350 (??, ??, ??)
  [05F39984]clnt_tcp_callit+000764 (F1000A05F8591228,
  0000000000000002,
     000000000615ED78, F00000002FF46EB0, 000000000615ED48,
  F00000002FF46F10,
     0000000000000005, 0000000000000000)
  [060EC860]lm_callrpc+000420 (??, ??, ??, ??, ??, ??, ??,
  ??)
  [060EFF40]lm4_frlock+000500 (??, ??, ??, ??, ??, ??, ??)
  [060E6B78]nfs3_frlock+000258 (??, ??, ??, ??, ??, ??)
  [05FA1B74]aix2onc_lockctl+0001F4 (??, ??, ??, ??, ??, ??,
  ??)
  [00692724]vnop_lockctl+000104 (??, ??, ??, ??, ??, ??,
  ??)
  [0078A658]lockf_common+000238 (??, ??, ??, ??)
  [00003938]syscall+000230 ()
  [D02FD9D4]lockf+0000D4 (??, ??, ??)
  [100003F0]main+000070 (00000001, 2FF22C28)
  [100001B8]__start+000068 ()
  [kdb_read_mem] no real storage @ FFFFFFFFFFF9240
  

Local fix

Problem summary

• A lock on an NFS3 file may fail to get released during
  unlock/cancel. Subsequent lock attempts on the file by
  other processes will fail when this happens.
  

Problem conclusion

• Ensure that client always sends cancel when it terminates, and
  also enhance the client to handle the case where the server
  failed to receive an earlier cancel request, and grants the
  lock to a client side process that no longer exists.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  IJ06516 IJ06522 IJ07613 IJ08087 IJ09426

Fix information

• Fixed component name

  AIX V7.1

• Fixed component ID

  5765H4000

Applicable component levels

• R710 PSY U879113

     UP19/01/23 I 1000