APAR status
Closed as program error.
Error description
Error Message: A SIGSEG is received during class unloading. . Stack Trace: {libj9jit29.so}{J9Method_HT::onClassUnloading(J9ClassLoader*)} {libj9jit29.so}{jitHookClassLoaderUnload(J9HookInterface**,...) } {libj9hookable29.so}{J9HookDispatch(J9HookInterface**,...)} {libj9vm29.so}{cleanUpClassLoader} {libj9gc29.so}{MM_ClassLoaderManager::cleanUpClassLoaders(...)} . The problem can occur on any platform running the J9 JVM starting with Java 8.0.5.0. Releases prior to that do not have this problem.
Local fix
The problem can be avoided by disabling the Dynamic Loop Transfer optimization in the JIT. This will have a small effect on startup performance as it might take longer for some methods to start running in compiled code form. -Xjit:disableDynamicLoopTransfer
Problem summary
The JIT would fail to remove some data referencing methods of classes that are being unloaded. This results in future unload attempts to fail when attempting to access memory from methods that have already been unloaded previously resulting in a SEGV if that memory has been allocated for other purposes.
Problem conclusion
The JIT has been modified so that references to classes being unloaded is properly removed. . This APAR will be fixed in the following Java Releases: 8 SR6 FP15 (8.0.6.15) . 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
IJ25403
Reported component name
JIT
Reported component ID
620700124
Reported release
130
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt / Xsystem
Submitted date
2020-06-04
Closed date
2020-07-28
Last modified date
2020-07-28
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":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSNVBF","label":"Runtimes for Java Technology"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"130","Line of Business":{"code":"LOB36","label":"IBM Automation"}}]
Document Information
Modified date:
29 July 2020