PM48721: ABEND ASRB OCCURS IN XDH4 DUE TO AN OVERLAY

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• An abend ASRB occurs in EYU0XDH4 with the psw pointing x'540'
  to a LOAD instruction:  5810 8050.  The abend occurs due to Reg8
  not being a valid address for the EYUBXDFD.  We are in the
  DISC_FILTER_LOOP routine trying to terminate a thread, looping
  through the 256 thread set entries to discard any
  sets/filters/views allocated for the thread.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM V4R1M0 and V4R2M0 Users      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Various unpredictable results may be    *
  *                      observed when a time out occurs for a   *
  *                      CPSM API, WUI or CICS Explorer action   *
  *                      request, or an API REFRESH request, for *
  *                      CICS resources in a MAS.                *
  *                                                              *
  *                      The invalid results may include, but    *
  *                      are not limited to:                     *
  *                                                              *
  *                      -  actions performed for invalid        *
  *                         resources or not performed for valid *
  *                         resources.                           *
  *                                                              *
  *                      -  invalid records returned or missing  *
  *                         records for API REFRESH.             *
  *                                                              *
  *                      -  an overlay of storage in the DATx    *
  *                         dataspace.                           *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF that resolves this    *
  *                 APAR, all CMASes and MASes must be recycled  *
  *                 to pick up the new code.  The restarts need  *
  *                 not be performed at the same time, however   *
  *                 until a CMAS and its connected MASes are     *
  *                 restarted with the updated code, the problem *
  *                 may continue to occur.                       *
  ****************************************************************
  When an action request is issued through the API, WUI or CICS
  Explorer, or an API REFRESH request is issued, against CICS
  resources in a MAS, a namelist structure is passed along with
  the request.  The namelist is used to identify the resources to
  be processed, and provides an area for the MAS to provide
  feedback as to how the request progressed.
  
  The namelist structure is allocated by the CMAS in the DATx
  dataspace before passing the request to the MAS.  Since the DATx
  dataspace is shared between the CMAS and its MASes, the MAS can
  access the dataspace directly, reading it to determine which
  resources to process, and updating it with response data.
  
  If the CMAS times out the request to the MAS, it cleans up the
  structures associated with the request in the CMAS.  This
  includes freeing the DATx dataspace storage where the namelist
  resides.  If the request is processed in the MAS after the
  timeout occurs, and the storage has been reallocated for another
  process, then the MAS processing may encounter errors trying to
  perform processing for invalid resources.  Additionally, when
  the MAS processing updates the namelist with response data, it
  may overlay storage used by another unrelated process, resulting
  in that process failing.
  

Problem conclusion

• Updates have been made to provide a MAS controlled copy of the
  namelist so that it cannot be freed while the MAS is processing
  against it.
  
  -  When the request is received in the MAS, method EYU0CTER
     (CTER) will verify that the request is still valid, and if
     so, allocate storage in the MASx dataspace, copy the namelist
     data into the allocated area, and set this MAS controlled
     copy of the namelist as the namelist used in the request.
  
  -  When the request is ended in the MAS, method EYU0CTED (CTED)
     will verify that the request is still valid, and if so, will
     copy the namelist data from the MAS controlled copy of the
     namelist back into the CMAS controlled copy of the namelist.
     CTED will then free the MAS controlled copy of the namelist.
  
  -  Method EYU0CLTM (CLTM), which runs in a MAS after all
     requests have been terminated at MAS restart or MAS
     termination, and method EYU0CLET (CLET), which runs in a CMAS
     when a disconnect request is received for a MAS, will each
     look to see if the MAS orphaned any MAS controlled namelists
     (due to MAS task purges or abends), and if so, free them.
     CLTM will most likely perform this process when MAS restart
     or termination occurs, while CLET will most likely perform
     this processing when the MAS is cancelled or otherwise
     terminates without going through normal termination
     processing.
  

Temporary fix

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

Comments

• ž**** PE12/01/17 FIX IN ERROR. SEE APAR PM56144  FOR DESCRIPTION
  

APAR Information

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

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

  UK75245 UK75246

Modules/Macros

•    EYUBCTAB EYUBCTNL EYUQCTER EYURCLCB EYURCLCE
  EYURCOEB EYURCTER EYUTRCOM EYUYCTER EYUZCTER EYU0CLET EYU0CLEV
  EYU0CLIN EYU0CLTM EYU0CSLT EYU0CTBP EYU0CTBR EYU0CTBS EYU0CTED
  EYU0CTER EYU0CTES EYU0CTIN EYU0CTRC EYU0CTRM EYU0XLTP EYU9CMPU
  EYU9CMP3 EYU9CMP4 EYU9CMRU EYU9CMR3 EYU9CMR4
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R60M PSY UK75245

     UP12/01/10 P F201

• R70M PSY UK75246

     UP12/01/10 P F201

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.