PK60455: CICS ABENDS U1800 AT STARTUP WITH PROGRAM IN PLT

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• If a CICS Java program is included in the CICS PLT (stage 3),
  the CICS region will issue the following message and then
  terminate with a DFHKE1800 (U1800 abend):
  .
     DFHSR0606  Abend (code ........) has ben detected.
  .
  If this Java program is not included in the CICS PLT at
  startup, CICS will initialize without any problems.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS Users                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: A Java PLT program ABENDs when          *
  *                      running in USER key with Storage        *
  *                      Protection                              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A Java PROGRAM is defined with EXECKEY(USER) and is part of
  the Program List Table (PLT) to execute on CICS startup.
  Storage Protection is active.
  
  Because the PROGRAM is being run as part of PLT processing,
  the PROGRAM should be invoked in CICS key regardless of the
  EXECKEY value in the program definition. DFHAPLJ1 therefore
  overrides the TCB key field, EIS_PROGRAM_MODE, for the
  program changing it from J9 to J8. When the Java program is
  invoked from DFHSJIN, this is not honoured and the program
  is run in USER key.
  
  As part of the Java program running it makes a JCICS call
  which results in an EXEC CICS ADDRESS command to be issued.
  This starts running on a J9, but because the call could have
  switched to QR if necessary, DFHEIP switches back to what it
  thinks was the caller's original TCB, using the
  EIS_PROGRAM_MODE field. This causes CICS to switch the task
  to a different J8 TCB instead of the caller's J9 TCB, and
  in turn leads to CICS ABENDing as this is not the TCB that
  the JVM was started on.
  
  Additional Keywords: abendU1800 msgDFHKE1800 msgDFHSR0606
  

Problem conclusion

• CICS has been updated to not override EIS_PROGRAM_MODE in
  DFHLI1 if the PLT program has been invoked on a J9 TCB -
  as Java programs with EXECKEY(USER) are. This restores the
  behaviour to how CICS behaved prior to CICS TS 3.1.
  This contrasts with what the Customization Guide states, and
  a Documentation change will be made to the guide for Java
  programs only.
  
  The Customization Guide for CICS TS 3.1 (SRL: SC34-6429-04)
  will be updated as follows:
  
  In chapter 4 'Writing initialization and shutdown programs',
  the section titled 'Execution key for PLT programs' will
  be updated as follows:
  
  - Under the 'Execution key for PLT programs' title add the
    following line:
  
  At PLT time CICS handles Java and non-Java program differently.
  
  - After this add a title 'Non-Java Programs' before the
    paragraph starting "CICS always gives control to PLT programs
    in CICS Key'.
  
  - After this paragraph (including the 'Important' section')
    add a new paragraph titled 'Java Programs' as follows:
  
  Java Programs
  A Java program in the PLT runs in the key defined in its
  PROGRAM resource definition (EXECKEY) and is not overridden
  to run in CICS key, unlike all other program types.
  
  When a Java program runs, a JVM is created if one does not
  already exist for that JVM profile in the key the program is
  executing. If REUSE=YES is specified in the corresponding JVM
  profile, the JVM persists after the Java program has ended.
  If a Java program, that is defined as EXECKEY(USER), was
  overridden to start in CICS key at PLT time, any subsequent
  invocations of that program would run in USER key and would
  therefore not be able to reuse the JVM created when the program
  ran at PLT time. Other Java programs that are defined with
  EXECKEY(USER) and use the same JVM Profile would also not be
  able to access the JVM that is started at PLT time. Therefore
  CICS does not override the execution key of Java programs at PLT
  time.
  
  If you want to run an EXECKEY(USER) Java program in CICS key
  at PLT time:
  1. Create a separate PROGRAM resource definition using the
  same JVMCLASS attribute value and specify EXECKEY(CICS).
  2. Add the PROGRAM resource definition to the PLT.
  
  The original PROGRAM resource definition with EXECKEY(USER)
  can then be used subsequently.
  
  -------------------------------------------------------------
  
  The Customization Guide for CICS TS 3.2 (SRL: SC34-6814-01)
  will be updated as follows:
  
  In chapter 4 'Writing initialization and shutdown programs',
  the section titled 'Execution key for PLT programs' will
  be updated as follows:
  
  - Under the 'Execution key for PLT programs' title add the
    following line:
  
  At PLT time CICS handles Java and non-Java program differently.
  
  - After this add a title 'Non-Java Programs' before the
    paragraph starting "CICS always gives control to PLT programs
    in CICS Key'.
  
  - After this paragraph (including the 'Important' section')
    add a new paragraph titled 'Java Programs' as follows:
  
  Java Programs
  A Java program in the PLT runs in the key defined in its
  PROGRAM resource definition (EXECKEY) and is not overridden
  to run in CICS key, unlike all other program types.
  
  When a Java program runs, a JVM is created if one does not
  already exist for that JVM profile in the key the program is
  executing. If REUSE=YES is specified in the corresponding JVM
  profile, the JVM persists after the Java program has ended.
  If a Java program, that is defined as EXECKEY(USER), was
  overridden to start in CICS key at PLT time, any subsequent
  invocations of that program would run in USER key and would
  therefore not be able to reuse the JVM created when the program
  ran at PLT time. Other Java programs that are defined with
  EXECKEY(USER) and use the same JVM Profile would also not be
  able to access the JVM that is started at PLT time. Therefore
  CICS does not override the execution key of Java programs at PLT
  time.
  
  If you want to run an EXECKEY(USER) Java program in CICS key
  at PLT time:
  1. Create a separate PROGRAM resource definition using the
  same JVMCLASS attribute value and specify EXECKEY(CICS).
  2. Add the PROGRAM resource definition to the PLT.
  
  The original PROGRAM resource definition with EXECKEY(USER)
  can then be used subsequently.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

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

  UK38206 UK38207

Modules/Macros

•    DESLI1   DFHAPLI1 DFHAPLJ1 DFHAPLX1
  

Fix information

• Fixed component name

  CICSTS V3 Z/OS

• Fixed component ID

  5655M1500

Applicable component levels

• R400 PSY UK38206

     UP08/07/19 P F807

• R500 PSY UK38207

     UP08/07/19 P F807

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.