PI97165: TRACE TABLE OVERLAID. ABEND0C4 ON MVCL IN DFHTRPX BECAUSE A LENGTH IS NEGATIVE.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Parts of the raw above-the-bar internal trace table are
  overlaid.  The overlaying data could be Kernel stack storage
  with eyecatchers like F4SA.  It could be CICS control blocks or
  application storage.
  .
  Possibly, most of the raw above-the-bar trace table looks good
  except for the 1st x'20' bytes of each 4K page.  The first
  x'30' bytes of each 4K page should look something like this:
  ---------------------
  ASID(X'006A') ADDRESS(50_00000000.) STORAGE --------
  _0000000:   00000050   00001000   00000050   027FF000
  _0000010:   00000000   00000000   D42FC2FE   58000000
  _0000020:   4C6E018A   00140500   C042177C   007B0015
  --------------------------
  The first double word should be a pointer to the next 4K page.
  The next double word should be a pointer to the prior 4K page.
  The first trace entry begins at +x'20' into the page with the
  x'4C6E' bytes.
  .
  Below is an example where the trace entry looks good starting
  x'20' into the page, but the 1st x'20' bytes are overlayed.
  -------------------------------------
  ASID(X'006A') ADDRESS(50_02784000.) STORAGE --------
  _2784000:   F9F9F9F9   F9F9F0C1   F0F0F0F0   F2F9F9F7
  _2784010:   F4F460F2   F0F0F0F0   D42FC2FE   58000000
  _2784020:   4C6E01E2   00101940   C041915C   0067C5E5
  -----------------------------
  .
  Sometimes the Trace Domain Anchor block ( TRA ) has an invalid
  TRA_NAB (which is the double word at +x20 into the TRA.)  When
  invalid, it does not fall within the bounds of the trace table.
  The double word at TRA +x50 is the beginning of the trace
  table. The double word at TRA +x'58 is the end of the trace
  table.
  .
  If TRA_NAB is bad like that, then each attempt to write a trace
  entry can abend0C4 in DFHTRPX and DFHTRPT because TRA_NAB is
  the address where the next trace entry will be placed.  This
  can result in a kernel stack looking like this:
  .
  0340 Dom  3334EDC8 333504A7 0016DF *Y* DFHTRPT
  1290 Dom  333AA3B8 333AB383 000FCB     DFHMEME
       Int   +004BA6 00000000 C55C48     TRACE_MEME_PLIST
       Int   +000F8A 333AEF88 004BD0     TRACE_DATA
  0340 Dom  3334EDC8 333504A7 0016DF *Y* DFHTRPT
  1290 Dom  333AA3B8 333AB383 000FCB     DFHMEME
       Int   +004BA6 00000000 C55C48     TRACE_MEME_PLIST
       Int   +000F8A 333AEF88 004BD0     TRACE_DATA
  0340 Dom  3334EDC8 333504A7 0016DF *Y* DFHTRPT
  1290 Dom  333AA3B8 333AB383 000FCB     DFHMEME
       Int   +004BA6 00000000 C55C48     TRACE_MEME_PLIST
       Int   +000F8A 333AEF88 004BD0     TRACE_DATA
  0340 Dom  3334EDC8 333504A7 0016DF *Y* DFHTRPT
  .
  And ultimately, CICS can abend with a KERNDUMP issued with the
  following message:
  .
  DFHKE0303  DBDCCICS A RECURSIVE ABEND HAS BEEN DETECTED BY THE
  KERNEL DOMAIN.
  .
  This problem is caused by a DFHXMERM domain call in module
  DFHISXM that does not properly CLEAR the domain call parameter
  list.  This problem will only occur during tasks that are
  initiated by input from an IPCONN connection.  Also, the path
  of the bad domain call only happens when the task has been
  purged prior to getting started (for example purged while
  queued for TRANCLASS reasons.)
  
  Additional Symptom(s) Search Keyword(s): KIXREVDWZ
  DFHXM0001 An abend (code 0C4/AKEA) has occurred at offset
    X'01AA' in module DFHXMER.
  AKC3 UAKC3 abendAKC3
  

Local fix

• turn off XM component tracing with STNTRXM=OFF and SPCTRXM=OFF
  
  
  
  Additional Keywords:   overlay MVCL DATA1
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS Users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Repeated abend 0C4 in DFHTRPX and       *
  *                      DFHTRPT.                                *
  ****************************************************************
  Module DFHISXM fails to clear the existence bits on a domain
  call for inquire_deferred_abend. This can result in the trace
  routines picking up residual data leading to a loop of
  abendS0C4s.
  Keywords: S0C4 MVCL overlay msgDFHKE0303
  

Problem conclusion

• DFHISXM has been changed in refstep isxm_ensure_abend_set to
  add a clear to the DFHXMERM calls.
  

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:

  UI58607 UI58608 UI58609 UI58610

Modules/Macros

• DFHISXM
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R000 PSY UI58607

     UP18/09/21 P F809

• R100 PSY UI58610

     UP18/09/21 P F809

• R800 PSY UI58608

     UP18/09/24 P F809

• R900 PSY UI58609

     UP18/09/24 P F809

Fix is available

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