APAR status
Closed as program error.
Error description
Error Message: A SIGSEGV is received when executing JIT compiled code. . Stack Trace: {java/util/regex/Pattern$Curly.match} JIT {com/myproclassic/server/services/card/PCECardHandlingBean.match PatternList} JIT {com/myproclassic/server/services/card/PCECardHandlingBean.match PatternListWithReplace} JIT {com/myproclassic/server/services/card/PCECardHandlingBean.match } JIT {com/myproclassic/server/services/card/PCECardHandlingBean.getEl ementResult} JIT This stack trace is one example of the problem. Since the problem could potentially occur in other JIT compiled methods, any crash in JIT compiled code is a potential example of this problem. . The problem can occur on any platform or OS when using the J9 JVM, but the problem will be very intermittent because the crash will only occur when a specific object is allocated right and the end of the Java heap. Therefore the chances of hitting the problem is very slim. If the address of the illegal access is not just beyond the end of the Java heap then this APAR does NOT apply.
Local fix
The problem can be avoid by disable a JIT optimization using the following java command line option: -Xjit:disableBlockVersioner Using this option will have a minor effect on performance, but the cost is very likely to be less then 2% in almost all most cases.
Problem summary
When attempting to generate an optimized path by removing array-bounds-checks the JIT would introduce new upper and lower bound checks to insure the optimized path can safely remove the array-bounds-checks. In doing so it introduced code that could potentially attempt to read passed the end of an object.
Problem conclusion
The JIT was modified so that it will verify the object that it is reading from is an instance of the class type we are expecting. . This APAR will be fixed in the following Java Releases: 8 SR6 FP10 (8.0.6.10) . 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
IJ24023
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-03-31
Closed date
2020-04-03
Last modified date
2020-04-03
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":"130","Edition":"","Line of Business":{"code":"","label":""}}]
Document Information
Modified date:
03 April 2020