Java 15 on ARM - Execution failed: `main' threw exception: java.lang.NullPointerException: Cannot invoke "com.sun.jdi.VirtualMachine.setDebugTraceMode(int)" because "this.vm" is null

[2021-01-21T20:36:24.647Z] rerun:
[2021-01-21T20:36:24.647Z] cd /home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/scratch && \
[2021-01-21T20:36:24.647Z] DISPLAY=:0 \
[2021-01-21T20:36:24.647Z] HOME=/home/jenkins \
[2021-01-21T20:36:24.647Z] LANG=en_US.UTF-8 \
[2021-01-21T20:36:24.647Z] PATH=/bin:/usr/bin:/usr/sbin \
[2021-01-21T20:36:24.647Z] /home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdkbinary/j2sdk-image/bin/java \
[2021-01-21T20:36:24.647Z] -Dtest.vm.opts='-ea -esa -Xmx512m' \
[2021-01-21T20:36:24.647Z] -Dtest.tool.vm.opts='-J-ea -J-esa -J-Xmx512m' \
[2021-01-21T20:36:24.647Z] -Dtest.compiler.opts= \
[2021-01-21T20:36:24.647Z] -Dtest.java.opts= \
[2021-01-21T20:36:24.647Z] -Dtest.jdk=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdkbinary/j2sdk-image \
[2021-01-21T20:36:24.647Z] -Dcompile.jdk=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdkbinary/j2sdk-image \
[2021-01-21T20:36:24.647Z] -Dtest.timeout.factor=8.0 \
[2021-01-21T20:36:24.647Z] -Dtest.root=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk \
[2021-01-21T20:36:24.647Z] -Dtest.name=com/sun/jdi/AccessSpecifierTest.java \
[2021-01-21T20:36:24.647Z] -Dtest.file=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk/com/sun/jdi/AccessSpecifierTest.java \
[2021-01-21T20:36:24.647Z] -Dtest.src=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk/com/sun/jdi \
[2021-01-21T20:36:24.647Z] -Dtest.src.path=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk/com/sun/jdi \
[2021-01-21T20:36:24.647Z] -Dtest.classes=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/classes/com/sun/jdi/AccessSpecifierTest.d \
[2021-01-21T20:36:24.647Z] -Dtest.class.path=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/classes/com/sun/jdi/AccessSpecifierTest.d \
[2021-01-21T20:36:24.647Z] -Dtest.class.path.prefix=/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/classes/com/sun/jdi/AccessSpecifierTest.d:/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk/com/sun/jdi \
[2021-01-21T20:36:24.647Z] -Dtest.modules=jdk.jdi \
[2021-01-21T20:36:24.647Z] -classpath /home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/classes/com/sun/jdi/AccessSpecifierTest.d:/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/openjdk/openjdk-jdk/test/jdk/com/sun/jdi:/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/jvmtest/openjdk/jtreg/lib/javatest.jar:/home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/jvmtest/openjdk/jtreg/lib/jtreg.jar \
[2021-01-21T20:36:24.647Z] AccessSpecifierTest
[2021-01-21T20:36:24.647Z] STDERR:
[2021-01-21T20:36:24.647Z] [20ms] run args: [AccessSpecifierTarg]
[2021-01-21T20:36:24.647Z] VM initialization failed for: /home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdkbinary/j2sdk-image/bin/java -classpath /home/jenkins/workspace/Test_openjdk15_hs_sanity.openjdk_arm_linux/openjdk-tests/TKG/test_output_16112358856146/jdk_svc_sanity_2/work/classes/com/sun/jdi/AccessSpecifierTest.d -ea -esa -Xmx512m -Xdebug -Xrunjdwp:transport=dt_socket,address=212.47.246.7.adoptopenjdk.net:53645,suspend=y AccessSpecifierTarg
[2021-01-21T20:36:24.647Z]
[2021-01-21T20:36:24.647Z]
[2021-01-21T20:36:24.647Z] Target VM failed to initialize.
[2021-01-21T20:36:24.647Z] java.lang.NullPointerException: Cannot invoke "com.sun.jdi.VirtualMachine.setDebugTraceMode(int)" because "this.vm" is null
[2021-01-21T20:36:24.647Z] at VMConnection.open(VMConnection.java:157)
[2021-01-21T20:36:24.647Z] at TestScaffold.connect(TestScaffold.java:637)
[2021-01-21T20:36:24.647Z] at TestScaffold.startUp(TestScaffold.java:364)
[2021-01-21T20:36:24.647Z] at TestScaffold.startTo(TestScaffold.java:374)
[2021-01-21T20:36:24.647Z] at AccessSpecifierTest.runTests(AccessSpecifierTest.java:221)
[2021-01-21T20:36:24.647Z] at TestScaffold.startTests(TestScaffold.java:431)
[2021-01-21T20:36:24.647Z] at AccessSpecifierTest.main(AccessSpecifierTest.java:189)
[2021-01-21T20:36:24.647Z] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[2021-01-21T20:36:24.647Z] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64)
[2021-01-21T20:36:24.647Z] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
[2021-01-21T20:36:24.647Z] at java.base/java.lang.reflect.Method.invoke(Method.java:564)
[2021-01-21T20:36:24.647Z] at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:298)
[2021-01-21T20:36:24.647Z] at java.base/java.lang.Thread.run(Thread.java:832)
[2021-01-21T20:36:24.647Z]
[2021-01-21T20:36:24.647Z] JavaTest Message: Test threw exception: java.lang.NullPointerException
[2021-01-21T20:36:24.647Z] JavaTest Message: shutting down test
[2021-01-21T20:36:24.647Z]
[2021-01-21T20:36:24.647Z] STDOUT:
[2021-01-21T20:36:24.647Z] vmOpts: '-ea -esa -Xmx512m'
[2021-01-21T20:36:24.647Z] javaOpts: ''
[2021-01-21T20:36:24.647Z] ERROR: transport error 202: connect failed: Connection refused
[2021-01-21T20:36:24.647Z] ERROR: JDWP Transport dt_socket failed to initialize, TRANSPORT_INIT(510)
[2021-01-21T20:36:24.647Z] JDWP exit error AGENT_ERROR_TRANSPORT_INIT(197): No transports initialized [./src/jdk.jdwp.agent/share/native/libjdwp/debugInit.c:734]
[2021-01-21T20:36:24.647Z]
[2021-01-21T20:36:24.647Z] TEST RESULT: Failed. Execution failed: `main' threw exception: java.lang.NullPointerException: Cannot invoke "com.sun.jdi.VirtualMachine.setDebugTraceMode(int)" because "this.vm" is null
[2021-01-21T20:36:24.647Z] --------------------------------------------------

Start with test/jdk/com/sun/jdi/AccessSpecifierTest.java and reproduce the failure on Java 15 ARM Linux. Trace the connection setup through VMConnection.java:157 and TestScaffold.java:637, then verify that the target VM initializes, the JDWP transport connects, and AccessSpecifierTest completes without the NullPointerException.

Written by the indexing model from the issue text.