PM47007: ABENDAICA IS FOLLOWED BY ABEND U0999 AND CICS REGION TERMINATES.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You have a task which abends with an AICA then while it is
  terminating with the runaway your system comes down with an
  abendu0999.
    The dump shows:
  ABEND                 ---/0999  DFHKETIX  00000806
  TRAN_ABEND_PERCOLATE  ---/AICA  DFHSR1    00000598
  ABEND                 ---/0999  DFHKETIX  00000806
  PROGRAM_CHECK         0C4/AKEA  DFHKESCL  00000238
    The abend0C4 in DFHKESCL (UK34338) at offset +238, the failing
  instruction is a STM (9023 D000) instruction.  With register 13
  containing: 000A0000.  R13 was acquired from R10 (00000000) +60.
  R10 should contain the address the of last stack (PREV_STACK).
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: A user transaction has runaway and      *
  *                      abends AICA. This is followed by an 0C4 *
  *                      abend in DFHKESCL which causes CICS to  *
  *                      terminate.                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  DFHKETIX detects runaway of a user transaction when the PSW is
  at label UNDER_31 in DFHKEDRT.  This instruction immediately
  follows the window in which a 999 abend may be issued directly.
  Due to defective logic in the kernel, this following instruction
  is also considered part of the window, so a 999 abend is issued.
  This interrupts the logic to release an overflow stack segment,
  which leaves a bad value in TAS_CURRENT_STACK.  This leads to an
  0C4 in DFHKESCL, which causes CICS to terminate.
  
  Additional keywords: abend0C4 abendAICA U0999 S0C4 abendS0C4
  

Problem conclusion

• DFHKEDRT is changed to include an extra instruction at label
  KEDRTCLW.  This ensures that the instruction following the end
  of the safe window is not included in it.  Therefore when
  runaway occurs at label UNDER_31, the return address is changed
  to the kernel runaway handler.  This leads to an AICA abend
  being issued safely after DFHKEDRT has returned.
  A corresponding change is made to equivalent module DFHKEDOM
  for CICS Transaction Server for z/OS Version 4 Release 2.
  

Temporary fix

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

Comments

APAR Information

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

  PM42921

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

  UK73858 UK73859

Modules/Macros

•    DFHKEDOM DFHKEDRT
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R600 PSY UK73858

     UP11/11/19 P F111

• R700 PSY UK73859

     UP11/11/19 P F111

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.