PM43015: ABEND S0C4 IN CPSM MODULE EYU9XSTR +X'9CA'. REPORTED BY CICS MESSAGE DFHAP0707 AND DFHAP0001

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Your CICS region experiences an S0C4/AKEA abend in CPSM module
  EYU9XSTR. CPSM would normally step in and produce its own
  diagnostic dump. This does not occur. In the job log, you see
  messages similar to the following:
  .
  EYUXS1014I Task recovery starting for task ( 12345 ),
  transaction ( xxxx )
  EYUXS1015I Task recovery complete for task ( 12345 ),
  flags ( NNNNNNNN )
  DFHAP0707 An abend (code 0C4/AKEA) has occurred in task related
  user exit program EYU9XSTR.
  DFHAP0001 An abend (code 0C4/AKEA) has occurred at offset
  X'000009CA' in module EYU9XSTR.
  .
  DFHAP0701 An abend (code 0C4/AKEA) has occurred in exit program
  EYU9XLGR at exit point XPCTA.
  DFHAP0001 An abend (code 0C4/AKEA) has occurred at offset
  X'00000168' in module EYU9XLGR.
  .
  DFHAP0001 An abend (code 0C4/AKEA) has occurred at offset
  X'0000026C' in module DFHAPLI3.
  .
  If the CPSM MAS agent code does not complete successfully, CPSM
  shuts the MAS agent code down and cleans up it's control blocks.
  Part of this process involves disabling its TRUEs (Task Related
  User Exits).
  .
  There is a timing window during this period where the CONL task
  is trying to terminate and cleanup, but gets suspended in a
  UEMENQ out of DFHUEM trying to perform a DISABLE of the GLUEs
  and TRUE out of EYU9XLEV. Just prior to the branch to
  XLEV_DISABLE_EXITS, EYU9XLEV at label XLEV_FREE_AOPB freemains
  the XLWA_AOPB_VO storage. It does not clear the XLWA_AOPB_VO
  address in the XLWA.
  .
  For the task that experienced the S0C4, code in EYU9XSTR picked
  up the value in XLWA_AOPB_VO (XLWA +x'360') and  XLWA_AOPB_LEN
  (XLWA +x'364'). These values are no longer valid, but XSTR uses
  these values later to calculate addresses and lengths for an
  MVCL instruction, which then corrupts storage in the region.
  Depending on what storage is cleared by the MVCL instruction
  before it abends, various other tasks may experience abends such
  as S0C4 or S0C7.
  .
  Additional Keywords or Symptoms:
  MVCL XSTR_SRCH_AOPB XSTR_SRCH_CLR AOPB
  KIXREVSVR
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM V4R1M0 and V4R2M0 Users      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Abend S0C4/AKEA may occur in task       *
  *                      related user exit (TRUE) program        *
  *                      xxx9XSTR, when the CPSM agent code is   *
  *                      terminating in a MAS.                   *
  *                                                              *
  *                      Note that the full name of the program  *
  *                      for CPSM V4R1M0 is EYU9XSTR and the     *
  *                      full name of the program for CPSM       *
  *                      V4R2M0 will be identified as one of the *
  *                      following:                              *
  *                                                              *
  *                        EYU9XSTR                              *
  *                        CJA9XSTR                              *
  *                        CJB9XSTR                              *
  *                        CJC9XSTR                              *
  *                                                              *
  *                      This can occur if the MAS agent code is *
  *                      terminating because:                    *
  *                                                              *
  *                      -  the CICS region is terminating.      *
  *                                                              *
  *                      -  the COSH transaction or the MAS STOP *
  *                         action is issued.                    *
  *                                                              *
  *                      -  an error occurred during MAS         *
  *                         connect.                             *
  *                                                              *
  *                      The S0C4/AKEA can occur because         *
  *                      xxx9XSTR either is reading or modifying *
  *                      storage not accessible to the task.  If *
  *                      the abend occurs when xxx9XSTR is       *
  *                      modifying storage, a storage overlay    *
  *                      can occur that may result in subsequent *
  *                      abends in the MAS.                      *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF that resolves this    *
  *                 APAR, all CMASES and MASes must be           *
  *                 restarted.  The restarts do not need to      *
  *                 occur at the same time.                      *
  *                                                              *
  *                 Note that even though problem can only occur *
  *                 in a MAS, the solution changes modules that  *
  *                 also execute in a CMAS, and thus CMASes      *
  *                 should also be restarted.                    *
  ****************************************************************
  When the MAS agent code is terminated, module EYU9XLEV (XLEV)
  performs cleanup of CPSM allocated resources in the MAS.  As
  part of this process, XLEV frees the CPSM task table, but
  does not clear the pointer to the table.  Subsequently, XLEV
  will physically disable the CPSM XSRAB and XPCTA global user
  exit (GLUE) programs, and then logically disable the task
  termination TRUE xxx9XSTR.
  
  Since XLEV does not clear the pointer to the task table when it
  frees the table, it is possible that xxx9XSTR will be driven for
  task termination after the table has been freed, and before
  xxx9XSTR is logically disabled.  When this occurs, xxx9XSTR will
  attempt to process the task table.  If the storage has not been
  reused, then xxx9XSTR may abend when it attempts to read the
  table.  If the storage has been reused, xxx9XSTR may abend when
  it attempts to modify the table.
  

Problem conclusion

• XLEV has been updated to logically disable the task termination
  TRUE xxx9XSTR before freeing the task table.  XLEV has also been
  updated to clear the pointer to the task table when it frees it.
  
  Programs that access the task table, including:
  
    EYU0XLTP EYU9XLAP xxx9XLGR EYU9XLOP xxx9XSTR
  
  have been updated to verify that the task table pointer is valid
  before accessing the table.
  
  Finally, the MAS XDUREQ GLUE xxx9NLDR has been updated to not
  request suppression of abends in xxx9XSTR.
  

Temporary fix

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

Comments

APAR Information

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

  PM43024

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

  UK71178 UK71179

Modules/Macros

•    CJA9NLDR CJA9XLEV CJA9XLGR CJA9XSTR CJB9NLDR
  CJB9XLEV CJB9XLGR CJB9XSTR CJC9NLDR CJC9XLEV CJC9XLGR CJC9XSTR
  EYU0XLTP EYU9NLDR EYU9XLAP EYU9XLEV EYU9XLGR EYU9XLOP EYU9XSTR
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R60M PSY UK71178

     UP11/08/28 P F108

• R70M PSY UK71179

     UP11/08/28 P F108

Fix is available

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