IJ46958: GPF WITH JRE 11 Z/OS S390X-64 (BUILD 11.0.16+8). THE GPF APPEARS TO BE A BRANCH TO A BAD ADDRESS, FROM LIBJAVA.SO::GETBOOTTIME()

APAR status

• Closed as program error.

Error description

• Error Message: None
  .
  Stack Trace: The GPF appears to be a branch to a bad address,
  from libjava.so::getBoottime().
  bp: 0x0000005098cfb580 pc: 0x00000000153b9766
  ExtraSymbolsModule::CELQHROD+0x266 bp: 0x0000005098cfb780 pc:
  0xbaadf00ddeadbeef libjsig.so::j9copyright+0xbaadefbd2440052f
  bp: 0x0000005098cfb8c0 pc: 0x000000007c71cb90
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/libjava.so::getBoottime
  +0xb0 bp: 0x0000005098cfb9c0 pc: 0x000000007c71cc6c
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/libjava.so::os_initNati
  ve+0x24 bp: 0x0000005098cfbac0 pc: 0x000000007c71bc6c
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/libjava.so::Java_java_l
  ang_ProcessHandleImpl_initNative+0x74 bp: 0x0000005098cfbbc0 pc:
  0x000000007c800b70
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/default/libj9vm29.so::F
  FISYS+0x570 bp: 0x0000005098cfc280 pc: 0x000000007cb18c82
  ExtraSymbolsModule::ffi_call+0x56a bp: 0x0000005098cfc380 pc:
  0x000000007c93f1f2
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/default/libj9vm29.so::b
  ytecodeLoopCompressed+0x28692 bp: 0x0000005098cfcbc0 pc:
  0x000000007c800176
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/default/libj9vm29.so::c
  _cInterpreter+0x7e bp: 0x0000005098cfd140 pc: 0x000000007c80b5d6
  /java/java11_bit64_sr16_fp0/J11.0_64/lib/default/libj9vm29.so::s
  endClinit+0x54e
  .
  

Local fix

Problem summary

• The availability of proc/stat file and the value of bootTime in
  the file are suspected to be the reason for crash and handling
  of the same in ProcessHandleImpl_zos.c file has fixed the issue
  

Problem conclusion

• The code had adapted getBootTime() to z/OS by calling fgets()
  instead of getline(). But it missed a detail i.e., NULL cannot
  be passed as the first argument to fgets() (which getline() does
  accept). It either needs to allocate line on the stack or heap.
  So the completion of the z/OS adaptation of getBoottime() is
  done by stack allocating line and also not calling free() on it,
  because it is allocated on the stack
  .
  This APAR will be fixed in the following Releases:
  .
  IBM Semeru Runtimes
     11              11.0.19.0
  .
  Contact your IBM Product's Service Team for these Service
  Refreshes and Fix Packs.
  For those running stand-alone, information about the available
  maintenance can be found at:
             https://www.ibm.com/support/pages/java-sdk
  

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:

Fix information

• Fixed component name

  OPENJDK CLASS L

• Fixed component ID

  621800100

Applicable component levels