PI81501: EYUXL0905E ASRA IN WTCL ABEND0C4 IN GET_WGSC_QUERY ROUTINE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Running CPSM v530, you MAS region received a DFHAP0001 mesage
  for an abend 0C4 occurring at x'FFFF' in EYU9XLOP.  The real
  abend is occurring as an ASRA abend 0C4 in WTCL.  The CPSM
  exception tracing shows the following entries:
  .
   1234 WTCL      IDW0     Abend       *Abend*
   1234 WTCL      IDW0     Abend       *Abend*
   1234 WASV WDTR IDW0 WLM Excp      1 WASVWTCL CPSM
   1234 WDTR XLOP IDW0 WLM Excp     11 WDTRAPIE CPSM
  .
  The method stack for this abend is: WTCL,WASV,WDTR,XLOP
  .
  The abend 0C4 occurs in EYU0WTCL (base530), around offset
  x'BA6'.  It's psw is pointing to a MVC instruction:  D203 D5A8
  E000.  The abend is occurring in routine GET_WGSC_QUERY, within
  the EYUQXXEP SAVE macro.  It seems the Access Registers were
  not successfully cleared out.
  .
  .
  .
  Additional Symptom(s) and keyword(s): KIXREVSVR
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICSPlex SM V5R1M0, V5R2M0, V5R3M0 and   *
  *                 V5R4M0 Users                                 *
  ****************************************************************
  * PROBLEM DESCRIPTION: Unpredictable results may occur during  *
  *                      abend recovery if an abend occurs in a  *
  *                      CPSM WLM routing region in method       *
  *                      EYU0WTCL (WTCL) during the processing   *
  *                      of a route request, if the algorithm in *
  *                      use is GOAL or LNGOAL.                  *
  *                                                              *
  *                      Results seen include, but are not       *
  *                      limited to, the following:              *
  *                                                              *
  *                      -  an overlay of 8 bytes in CICS region *
  *                         storage in the routing region.       *
  *                                                              *
  *                      -  a secondary S0C4 abend in WTCL in    *
  *                         the routing region.                  *
  *                                                              *
  *                      Any subsequent route requests from any  *
  *                      routing region connected to the same    *
  *                      CMAS as the routing region that         *
  *                      experienced the original abend, that    *
  *                      should use the GOAL or LNGOAL           *
  *                      algorithms, may use the QUEUE or        *
  *                      LNQUEUE algorithms instead.             *
  ****************************************************************
  * RECOMMENDATION: After applying the PTF that resolves this    *
  *                 APAR, all MASes running as CPSM WLM routing  *
  *                 regions must be restarted.  Note that the    *
  *                 restarts do not need to occur at the same    *
  *                 time.                                        *
  ****************************************************************
  When a route request is received in a CPSM WLM routing region,
  method EYU0WTCL (WTCL) is called to classify the request based
  upon the transaction ID, and the userid and luname associated
  with the request.  If the algorithm being used for the request
  is GOAL or LNGOAL, then the EYUBWSGA control block, the WLM
  GOAL System Group Class Anchor, is retrieved and locked.  To
  lock the EYUBWSGA, WTCL uses a CDS instruction to modify the
  lock doubleword in the EYUBWSGA.
  
  If an abend occurs in WTCL, then recovery is driven.  During
  recovery, WTCL will attempt to unlock the EYUBWSGA, using the
  same CDS method it uses to lock the EYUBWSGA.  Since the
  EYUBWSGA resides in WLM data space storage, WTCL needs to be in
  access register (AR) mode when it attempts the unlock.
  However,since AR mode is turned off after the abend occurs and
  not turned back on by the recovery code in WTCL, the unlock
  request is made in primary space mode.  This will result in
  WTCL attempting to modify CICS region storage instead of WLM
  data space storage.  If the address WTCL is attempting to
  modify is in protected storage, then a S0C4 abend will occur.
  If the address is not in protected storage, than an 8 byte
  overlay will occur.
  
  In either case, the EYUBWSGA will remain locked, and subsequent
  route requests directed to any routing region connected to the
  same CMAS as the original routing region, which all access the
  same EYUBWSGA, will result in WTCL failing to acquire the lock.
  When that occurs, WTCL reverts to using the QUEUE or LNQUEUE
  algorithm instead of failing the route request.
  
  Note that in three locations in WTCL, AR14 in not cleared after
  being used, which could lead to the original abend that drives
  abend recovery in WTCL.
  

Problem conclusion

• The abend recovery routing in WTCL has been updated to enter
  AR mode prior calling the UNLOCK_WSGA subroutine, and to turn
  off AR mode upon returning from the subroutine.
  
  Additionally, WTCL has been updated to ensure that AR14 is
  cleared where appropriate.
  

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:

  PI82475 UI49446 UI49447 UI49448 UI49454

Modules/Macros

• EYU0WTCL
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R00M PSY UI49454

     UP17/08/15 P F708 ¢

• R10M PSY UI49448

     UP17/08/15 P F708 ¢

• R80M PSY UI49446

     UP17/08/15 P F708 ¢

• R90M PSY UI49447

     UP17/08/15 P F708 ¢

Fix is available

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