APAR status
Closed as program error.
Error description
Error Message: A SIGSEGV is received while executing findClassInfo() when the JIT is compiling a method. . Stack Trace: TR_PersistentCHTable::findClassInfo(TR_OpaqueClassBlock*)() TR_PersistentInfo::isObsoleteClass(void*,TR_FrontEnd*)() TR_PPCPrivateLinkage::buildVirtualDispatch(...)() ... . The issue is only known to occur on PowerPC machines. The issue is unlikely to occur on architectures that have strong memory coherency (like X86 or ZSeries).
Local fix
Depending on the release of Java, one of the following java command line options can be used to avoid the problem: Java 6/7.0: -Xjit:disableCHTable,disableCHOpts Java 7.1/8: -Xjit:disableCHOpts The use of the above options will have some effect on the execution performance of JIT compiled code.
Problem summary
The JIT compiler failed to use locking to prevent a compiler thread from reading from an internal data structure at the same time that another compiler thread is adding to the structure which can lead to a crash in findClassInfo() on architectures that have weak memory coherency.
Problem conclusion
The JIT was modified so that proper locking is used to prevent concurrent access to a JIT internal data structure. . This APAR will be fixed in the following Java Releases: 7 SR10 FP25 (7.0.10.25) 7 R1 SR4 FP25 (7.1.4.25) 6 R1 SR8 FP65 (6.1.8.65) 8 SR5 FP11 (8.0.5.11) . Contact your IBM Product's Service Team for these Service Refreshes and Fix Packs. For those running stand-alone, information about the available Service Refreshes and Fix Packs can be found at: https://www.ibm.com/developerworks/java/jdk/
Temporary fix
Comments
APAR Information
APAR number
IJ04875
Reported component name
JIT
Reported component ID
620700124
Reported release
260
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2018-03-12
Closed date
2018-04-03
Last modified date
2018-04-03
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
JIT
Fixed component ID
620700124
Applicable component levels
[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSC9HBA","label":"Just In Time (JIT) Compiler"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"260","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
03 April 2018