Test sun/misc/URLClassPath/ClassnameCharTest.java crashes with vthread wrapper at:
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x00007f482d5ccbe4, pid=25507, tid=3786
#
# JRE version: Java(TM) SE Runtime Environment (15.0) (fastdebug build 15-internal+0-2020-03-26-2156206.leonid.mesnik.loom)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 15-internal+0-2020-03-26-2156206.leonid.mesnik.loom, mixed mode, tiered, compressed oops, g1 gc, linux-amd64)
# Problematic frame:
# V [libjvm.so+0xd30be4] frame::sender_for_interpreter_frame(RegisterMap*) const+0xa4
#
# Core dump will be written. Default location: Core dumps may be processed with "/opt/core.sh %p" (or dumping to /opt/mach5/mesos/work_dir/slaves/b0d836b1-c68c-4dbd-8b78-5085890ddd4c-S1575/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/74f17fa1-12ba-4c42-a46b-4f313fb3f66f/runs/7322ba18-07ca-4d50-9e4b-6ca1178d337a/testoutput/test-support/jtreg_open_test_jdk_tier1_part1/scratch/1/core.25507)
#
# If you would like to submit a bug report, please visit:
# https://bugreport.java.com/bugreport/crash.jsp
#

--------------- S U M M A R Y ------------

Command Line: -Xmx512m -XX:MaxRAMPercentage=6 -ea -esa -Dmain.wrapper=Virtual -Djava.library.path=/opt/mach5/mesos/work_dir/jib-master/install/2020-03-26-2156206.leonid.mesnik.loom/linux-x64-debug.test/jdk/jtreg/native --patch-module=java.base=/opt/mach5/mesos/work_dir/slaves/b0d836b1-c68c-4dbd-8b78-5085890ddd4c-S1575/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/74f17fa1-12ba-4c42-a46b-4f313fb3f66f/runs/7322ba18-07ca-4d50-9e4b-6ca1178d337a/testoutput/test-support/jtreg_open_test_jdk_tier1_part1/patches/java.base -Djava.security.policy=file:/opt/mach5/mesos/work_dir/slaves/b0d836b1-c68c-4dbd-8b78-5085890ddd4c-S1575/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/74f17fa1-12ba-4c42-a46b-4f313fb3f66f/runs/7322ba18-07ca-4d50-9e4b-6ca1178d337a/./testoutput/test-support/jtreg_open_test_jdk_tier1_part1/jtreg.policy com.sun.javatest.regtest.agent.AgentServer -allowSetSecurityManager -port 45343 -timeoutFactor 4.0 -mainWrapper Virtual

Host: Intel(R) Xeon(R) Platinum 8167M CPU @ 2.00GHz, 8 cores, 58G, Oracle Linux Server release 7.7
Time: Thu Mar 26 22:54:32 2020 UTC elapsed time: 1349.847691 seconds (0d 0h 22m 29s)

--------------- T H R E A D ---------------

Current thread (0x00007f47c401a000): JavaThread "ForkJoinPool-1-worker-5" daemon [_thread_in_vm, id=3786, stack(0x00007f47fe4c7000,0x00007f47fe5c8000)]

Stack: [0x00007f47fe4c7000,0x00007f47fe5c8000], sp=0x00007f47fe5c3970, free space=1010k
Thread 0x00007f47c401a000 [3786]
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0xd30be4] frame::sender_for_interpreter_frame(RegisterMap*) const+0xa4
V [libjvm.so+0xd31624] frame::sender(RegisterMap*) const+0x64
V [libjvm.so+0x1987bdc] vframeStreamCommon::asJavaVFrame()+0x9c
V [libjvm.so+0x113e684] JVM_GetStackAccessControlContext+0x944
J 373 java.security.AccessController.getStackAccessControlContext()Ljava/security/AccessControlContext; java.base@15-internal (0 bytes) @ 0x00007f48182276e7 [0x00007f4818227600+0x00000000000000e7]
J 2686 c1 java.security.AccessController.getContext()Ljava/security/AccessControlContext; java.base@15-internal (23 bytes) @ 0x00007f48112fa204 [0x00007f48112fa1a0+0x0000000000000064]
j java.security.AccessController.doPrivilegedWithCombiner(Ljava/security/PrivilegedExceptionAction;Ljava/security/AccessControlContext;[Ljava/security/Permission;)Ljava/lang/Object;+0 java.base@15-internal
j sun.net.www.protocol.http.HttpURLConnection.lockedGetInputStream()Ljava/io/InputStream;+59 java.base@15-internal
j sun.net.www.protocol.http.HttpURLConnection.getInputStream()Ljava/io/InputStream;+5 java.base@15-internal
j java.net.HttpURLConnection.getResponseCode()I+16 java.base@15-internal
j sun.net.www.protocol.http.HttpURLConnection.getInputStream0()Ljava/io/InputStream;+436 java.base@15-internal
j java.lang.Continuation.run()V+184 java.base@15-internal
j java.lang.VirtualThread.runContinuation()V+89 java.base@15-internal
j java.lang.VirtualThread$$Lambda$56.run()V+4 java.base@15-internal
j java.util.concurrent.ForkJoinTask$RunnableExecuteAction.exec()Z+4 java.base@15-internal
j java.util.concurrent.ForkJoinTask.doExec()I+10 java.base@15-internal
j java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(Ljava/util/concurrent/ForkJoinTask;Ljava/util/concurrent/ForkJoinPool$WorkQueue;I)V+11 java.base@15-internal
J 1928 c2 java.util.concurrent.ForkJoinPool.scan(Ljava/util/concurrent/ForkJoinPool$WorkQueue;I)Z java.base@15-internal (212 bytes) @ 0x00007f48183acc14 [0x00007f48183ac940+0x00000000000002d4]
j java.util.concurrent.ForkJoinPool.runWorker(Ljava/util/concurrent/ForkJoinPool$WorkQueue;)V+25 java.base@15-internal
j java.util.concurrent.ForkJoinWorkerThread.run()V+24 java.base@15-internal
v ~StubRoutines::call_stub 0x00007f48107379ca
V [libjvm.so+0xfafdfc] JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, Thread*)+0x6ac
V [libjvm.so+0xfb03ae] JavaCalls::call_virtual(JavaValue*, Klass*, Symbol*, Symbol*, JavaCallArguments*, Thread*)+0x33e
V [libjvm.so+0xfb05ca] JavaCalls::call_virtual(JavaValue*, Handle, Klass*, Symbol*, Symbol*, Thread*)+0xca
V [libjvm.so+0x111edb7] thread_entry(JavaThread*, Thread*)+0x127
V [libjvm.so+0x18f3996] JavaThread::thread_main_inner()+0x226
V [libjvm.so+0x18f9986] Thread::call_run()+0xf6
V [libjvm.so+0x160882e] thread_native_entry(Thread*)+0x10e