IZ96936: COMPILED CODE PATCHING DURING CLASS UNLOADING LEADS TO INVALID J UMP TARGET.

APAR status

• Closed as program error.

Error description

• Error Message: A SEGSEGV/GPF is received when the application
  attempts to executed invalid code.
  .
  Stack Trace: N/A
  .
  

Local fix

• The workaround for this issue is to exclude the method in which
  the crash is occurring through:
  -Xjit:exclude={*Class.method*}
  

Problem summary

• To parts of the JIT generated code were registered as targets of
  dynamic patching. A jmp instruction was patched in at a target
  address, however a class unloading mechanism would come in an
  patch a -1 over the same target.
  

Problem conclusion

• This defect will be fixed in:
  6.0.0 SR9FP1
  5.0.0 SR12FP5
  .
  The issue has been resolved in the JIT and the two patching
  sites no longer overlap.
  .
  To obtain the fix:
  Install build 20110405 or later
  

Temporary fix

Comments

APAR Information

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

  IZ96935

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

Fix information

• Fixed component name

  JAVA 5 JIT

• Fixed component ID

  620500124

Applicable component levels

• R500 PSY

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