Bug 2229269

Summary:	Backport JDK-8243210
Product:	Red Hat Enterprise Linux 8	Reporter:	Mike Millson <mmillson>
Component:	java-11-openjdk	Assignee:	Thomas Stuefe <tstuefe>
Status:	POST ---	QA Contact:	OpenJDK QA <java-qa>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	8.4	CC:	sgehwolf, ssanghav
Target Milestone:	rc	Flags:	ahughes: needinfo? (mmillson)
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OS:	Unspecified
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
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Embargoed:

Description Mike Millson 2023-08-04 16:45:54 UTC

Backport the null check in JDK-8243210[1] to avoid the following NPE when getting a thread dump:

~~~
Exception in thread "main" java.lang.NullPointerException
        at jdk.hotspot.agent/sun.jvm.hotspot.memory.FileMapInfo$FileMapHeader.inCopiedVtableSpace(FileMapInfo.java:124)
        at jdk.hotspot.agent/sun.jvm.hotspot.memory.FileMapInfo.inCopiedVtableSpace(FileMapInfo.java:104)
        at jdk.hotspot.agent/sun.jvm.hotspot.types.basic.BasicTypeDataBase.findDynamicTypeForAddress(BasicTypeDataBase.java:302)
        at jdk.hotspot.agent/sun.jvm.hotspot.runtime.VirtualBaseConstructor.instantiateWrapperFor(VirtualBaseConstructor.java:102)
        at jdk.hotspot.agent/sun.jvm.hotspot.oops.Metadata.instantiateWrapperFor(Metadata.java:73)
        at jdk.hotspot.agent/sun.jvm.hotspot.oops.Oop.getKlassForOopHandle(Oop.java:210)
        at jdk.hotspot.agent/sun.jvm.hotspot.oops.ObjectHeap.newOop(ObjectHeap.java:254)
        at jdk.hotspot.agent/sun.jvm.hotspot.oops.ObjectHeap.iterateLiveRegions(ObjectHeap.java:333)
        at jdk.hotspot.agent/sun.jvm.hotspot.oops.ObjectHeap.iterate(ObjectHeap.java:174)
        at jdk.hotspot.agent/sun.jvm.hotspot.utilities.AbstractHeapGraphWriter.write(AbstractHeapGraphWriter.java:51)
        at jdk.hotspot.agent/sun.jvm.hotspot.utilities.HeapHprofBinWriter.write(HeapHprofBinWriter.java:443)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.writeHeapHprofBin(JMap.java:182)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.run(JMap.java:97)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.startInternal(Tool.java:260)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.start(Tool.java:223)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.Tool.execute(Tool.java:118)
        at jdk.hotspot.agent/sun.jvm.hotspot.tools.JMap.main(JMap.java:176)
        at jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.runJMAP(SALauncher.java:369)
        at jdk.hotspot.agent/sun.jvm.hotspot.SALauncher.main(SALauncher.java:538)
~~~

[1]https://bugs.openjdk.org/browse/JDK-8243210