PI46433: FFDC is produced for a NullPointerException in com.ibm.ws.tcpcha nnel.internal.SocketRWChannelSelector.updateSelector.

8.5.5.7: WebSphere Application Server V8.5.5 Fix Pack 7
8.5.5.8: WebSphere Application Server V8.5.5 Fix Pack 8
8.5.5.9: WebSphere Application Server V8.5.5 Fix Pack 9
8.5.5.10: WebSphere Application Server V8.5.5 Fix Pack 10
8.5.5.11: WebSphere Application Server V8.5.5 Fix Pack 11
8.5.5.12: WebSphere Application Server V8.5.5 Fix Pack 12
8.5.5.13: WebSphere Application Server V8.5.5 Fix Pack 13
8.5.5.14: WebSphere Application Server V8.5.5 Fix Pack 14
8.5.5.15: WebSphere Application Server V8.5.5 Fix Pack 15
8.5.5.17: WebSphere Application Server V8.5.5 Fix Pack 17
8.5.5.20: WebSphere Application Server V8.5.5.20
8.5.5.18: WebSphere Application Server V8.5.5 Fix Pack 18
8.5.5.19: WebSphere Application Server V8.5.5 Fix Pack 19
8.5.5.16: WebSphere Application Server V8.5.5 Fix Pack 16
8.5.5.21: WebSphere Application Server V8.5.5.21

APAR status

• Closed as program error.

Error description

• Very rarely, an FFDC is produced indicating a
  NullPointerException similar to the following:
  
  >Exception = java.lang.NullPointerException
  >Source =
  com.ibm.ws.tcpchannel.internal.SocketRWChannelSelector
  >probeid = 254
  >Stack Dump = java.lang.NullPointerException
  > at
  com.ibm.ws.tcpchannel.internal.SocketRWChannelSelector.updat
  eSelector(SocketRWChannelSelector.java:193)
  > at
  com.ibm.ws.tcpchannel.internal.ChannelSelector.run(ChannelSe
  lector.java:227)
  > at java.lang.Thread.run(Thread.java:804)
  
  The error itself is harmless other than the appearance of
  the FFDC.  It is produced because the ChannelSelector thread
  is processing connections that may have been closed by
  another thread, and there is a timing window where the
  ChannelSelector, while attempting to write an event trace,
  will dereference a null field obtained from a closed
  connection.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:  All users of IBM WebSphere Application      *
  *                  Server Liberty Profile - Channel Framework  *
  ****************************************************************
  * PROBLEM DESCRIPTION: FFDC is produced for a                  *
  *                      NullPointerException in                 *
  *                      com.ibm.ws.tcpchannel.internal.SocketRW *
  *                      ChannelSelector.updateSelector.         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Very rarely, an FFDC is produced indicating a
  NullPointerException similar to the following:
  
  >Exception = java.lang.NullPointerException
  >Source =
  com.ibm.ws.tcpchannel.internal.SocketRWChannelSelector
  >probeid = 254
  >Stack Dump = java.lang.NullPointerException
  > at
  com.ibm.ws.tcpchannel.internal.SocketRWChannelSelector.updateSel
  ector(SocketRWChannelSelector.java:193)
  > at
  com.ibm.ws.tcpchannel.internal.ChannelSelector.run(ChannelSelect
  or.java:227)
  > at java.lang.Thread.run(Thread.java:804)
  
  The error itself is harmless other than the appearance of the
  FFDC.  It is produced because the ChannelSelector thread is
  processing connections that may have been closed by another
  thread, and there is a timing window where the ChannelSelector,
  while attempting to write an event trace, will dereference a
  null field obtained from a closed connection.
  

Problem conclusion

• Code was added to check for null and avoid the
  NullPointerException.
  
  The fix for this APAR is currently targeted for inclusion in fix
  pack 8.5.5.7.  Please refer to the Recommended Updates page for
  delivery information:
  http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980
  

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:

  PI47257

Fix information

• Fixed component name

  WAS LIBERTY COR

• Fixed component ID

  5725L2900

Applicable component levels

• R855 PSY

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