PK92112: LOOP IN DFHMQTRU AT SHUTDOWN AFTER PREVIOUS MQ TASK IS PURGED OR ABENDS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Loop in DFHMQTRU occurs during a normal CICS shutdown. The last
  message prior to the loop is:
  .
  DFHMQ0411I date time applid CICS warm shutdown detected.
                              Adapter is quiescing.
  .
  The loop occurs while DFHMQTRU is running the dfhmqloc.THDChain
  and one of the threads points to itself. The problem can happen
  if there is an MQ crossing exit CSQCAPX active, and a task is
  purged or abends while control is in MQ. If the task is purged
  or abends here, the associated TIE will be freed at task
  termination, but the DFHMQTHD within that TIE will be left on
  the thread chain. The CEMT shutdown task may get the same TIE
  as the purged/abended task. Since that thread was already on the
  thread chain, adding it to it again causes it to point to
  itself and the loop will then occur.
  .
  Additional Symptom(s) Search Keyword(s):
  CONNCHN PNEXT CTHD.ConnChn.pNext  MQTHD DFHMQ0411 AEXY abendAEXY
  MQLOT  PBASEASTG PTRUEASTG valid_uow_environment  KIXREVDWZ
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION: CICS shutdown hangs after message       *
  *                      DFHMQ0411I is issued.                   *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Shutdown of a CICS system connected to WMQ hangs because the
  CEMT shutdown task is looping.
  Keywords: msgDFHMQ0411 msgDFHMQ0411I DFHMQ0411 MQ0411 MQ0411I
  

Problem conclusion

• DFHMQTRU has been changed so that storage pointers, altered on
  entry to the crossing exit call (CSQCAPX), are correctly
  re-instated after return from the call.
  

Temporary fix

•             *********
              * HIPER *
              *********
  FIX AVAILABLE BY PTF ONLY
  

Comments

• ž**** PE11/07/05 FIX IN ERROR. SEE APAR PM39132  FOR DESCRIPTION
  

APAR Information

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

  PK91807

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

  UK49815

Modules/Macros

•    DFHMQTRU
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R600 PSY UK49815

     UP09/09/09 P F909

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.