OA59390: On z15, zEDC enabled zlib classes may fail decompression becauseof incorrectly encoded symbols 20/04/13 PTF PECHANGE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When compressing data on a z15 using zEDC enabled classes in
  java or using the zEDC enabled zlib an error may occur that
  can result in a bad symbol in the compressed data stream.
  The bad symbol is detected as various errors when decompressing
  the data such as: Corrupt GZIP trailer or invalid stored block
  lengths.
  
  PE Information:
  Users Affected: Users with APAR OA56143 installed who use
  zEDC zlib or zEDC enables classes in Java
  to compress data on a z15 processor.
  
  User Impact: Development APAR OA56143 provided software
  support for the z15 processor compression but
  introduced a new problem.
  This error may result in various Java/zlib
  errors, such as Corrupt GZIP trailer, invalid
  stored block, or invalid distance code.
  Users are clearly better off with the original
  APAR on the system: The original APAR supports
  the z15 processor compression, but introduces
  an intermittent problem when using zEDC zlib
  services or zEDC enabled classes in Java.
  

Local fix

• BYPASS/CIRCUMVENTION:
  _HZC_COMPRESSION_METHOD=SOFTWARE can be set for any application
  that is exploiting zLib compression so that hardware compression
  will be bypassed.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users at HBB77A0 and above.                                  *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * An exception can occur when                                  *
  * decompressing data compressed on a                           *
  * z15 using zlib hardware compression.                         *
  * This is a result of an error during                          *
  * compression, that causes a variety                           *
  * of java.util.zip.ZipException to be                          *
  * thrown on decompression: corrupt GZIP                        *
  * trailer, invalid stored block lengths,                       *
  * or invalid distance code.                                    *
  * (ZEDC/K) (R8561/K)                                           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When compressing data on a z15 using zEDC enabled classes in
  java or using the zEDC enabled zlib an error may occur that
  can result in a bad symbol in the compressed data stream.
  The bad symbol is detected as various errors when decompressing
  the data such as: Corrupt GZIP trailer , invalid stored block
  lengths, or invalid distance code.
  

Problem conclusion

• The error during compression that leads to a java.util.zip.
  ZipException during decompression has been corrected.
   KEYWORDS: ZEDC/K
  

Temporary fix

• *********
  * HIPER *
  *********
  

Comments

APAR Information

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

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

  UJ02752 UJ02753 UJ02754 UJ02755

Modules/Macros

• IGVDGNB  FPZPRCS2 IGVDGNTM
  

Fix information

• Fixed component name

  PCIE SERVICES

• Fixed component ID

  5752SCIQP

Applicable component levels

• R790 PSY UJ02755

     UP20/05/06 P F005 ­

• R7A0 PSY UJ02754

     UP20/05/06 P F005 ­

• R7B0 PSY UJ02752

     UP20/05/06 P F005 ­

• R7C0 PSY UJ02753

     UP20/05/06 P F005 ­

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.