PQ84168: ABENDC78 REASON 18 IN IGVCPEXT DUE TO INVALID CPID FROM EZBSOMIFAFTER FAILED INITAPI

APAR status

• Closed as unreproducible.

Error description

• Application issued an INITAPI which failed, in this case with
  errno 156 because no OMVS Segment was defined.  The application
  followed the INITAPI with another socket command, in this case
  GETHOSTID, which caused a default INITAPI to be issued.  Again
  the INITAPI failed but in this case the EZSOMIF code path
  attempted to issue a CPOOL GET using a cell pool id (CPID) from
  the socket descriptor control block, SDST, which had been freed
  due to the error on the INITAPI.  The CPOOL request then abended
  with ABENDC78 reason code 18.
  VERIFICATION STEPS:
  1) Abend occurs in IGVCPEXT with reason code 18
  2) Use systrace to find the TCB that abended. Issue SUMM FORMAT
     and find the TCB.  The last linkage stack entry for the
     first RB will have a PSW of IGVCPOOL on the PC to IGVCPEXT.
     Reg 14 will point into EZBSOMIF, Reg 13 points to EZBSOMIF
     register save area (EZBSOMIF eyecatcher at -8 bytes). In the
     register save area the MACP address and SDST address can
     be found.  Review EZBSOMIF code but at this level (UQ70213)
     Reg7 = SDST and Reg8 = MACP.  The SDST will be zeros in
     both the register and in the MACP.
  3) A CTRACE will show that a default INITAPI had been issued
     on behalf of another socket request (look at MACP function
     field) and failed.
  Additional Symptoms:
  

Local fix

• Correct the problem causing the INITAPI to fail.
  KEYWORDS: ABEND C78 ABENDC78 INITAPI Cell pool id CPID EZBSOMIF
       IGVCPEXT
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Releases 2 and 4 IP:      *
  *                 macro API                                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: ABENDC78 due to an invalid CPOOL GET    *
  *                      request by EZBSOMIF                     *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  An EZASMI application issued an INITAPI with the ASYNC option.
  However, the INITAPI failed with errno 156 because the OMVS
  RACF segment was not defined.  The application assumed that the
  INITAPI had succeeded and issued a GETHOSTID with the REQAREA
  option.  Since no successful INITAPI had completed, Sockets
  Transform attempted a default INITAPI which also failed with
  errno 156.  Hence, the GETHOSTID failed.  EZBSOMIF called
  its MIRA_PTR procedure to see if the GETHOSTID call needed to be
  completed pseudo-asynchronously.  Because a REQAREA was present,
  MIRA_PTR erroneously decided that it did.  This caused a C78
  system ABEND because EZBSOMIF's pseudo-asynchronous completion
  routine attempted to get a cell from the RSA cell pool which did
  not exist since there was no successful INITAPI.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

Temporary fix

Comments

• This problem has been rectified in the Communications Server for
  z/OS Release 5 IP via PTR MV27900 and the APAR will close
  without a PTF, as agreed with the submittor.
  
  MV27900 changes EZBSOMIF's MIRA_PTR procedure so that it
  recognizes that there is no pseudo-asynchronous completion if
  there is no SDST.
  

APAR Information

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

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

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R120 PSN

     UP

• R140 PSN

     UP