The following test started failing in my stress testing in jdk-21+18:

com/sun/jdi/ConnectedVMs.java

Here's a snippet from the log file:

#section:driver
----------messages:(7/229)----------
command: driver ConnectedVMs Kill
reason: User specified action: run driver ConnectedVMs Kill
started: Sat Apr 15 06:02:08 EDT 2023
Mode: agentvm
Agent id: 25
finished: Sat Apr 15 06:02:08 EDT 2023
elapsed time (seconds): 0.318
----------configuration:(12/1238)----------

<snip>

----------System.out:(10/712)----------
create Kill
Testing Kill
vmOpts: '-Xmx768m -XX:MaxRAMPercentage=2.08333 -Dtest.boot.jdk=/work/local/jib-dcubed/install/jdk/19/36/bundles/macos-aarch64/jdk-19_macos-aarch64_bin.tar.gz/jdk-19.jdk/Contents/Home -Djava.io.tmpdir=/System/Volumes/Data/work/shared/bug_hunt/thread_SMR_stress/jdk21_exp.git/build/macosx-aarch64-normal-server-fastdebug/test-support/jtreg_open_test_jdk_jdk_svc/tmp -ea -esa'
javaOpts: ''
JVM version:21-internal
JDI version: 21.0
JVM description: Java Debug Interface (Reference Implementation) version 21.0
Java Debug Wire Protocol (Reference Implementation) version 21.0
JVM Debug Interface version 21.0
JVM version 21-internal (Java HotSpot(TM) 64-Bit Server VM, mixed mode, sharing)
----------System.err:(15/779)----------
[1ms] run args: [InstTarg]
java.lang.RuntimeException: Non-zero debuggee exitValue: 143
        at TestScaffold.waitForVMDisconnect(TestScaffold.java:724)
        at TestScaffold.resumeToVMDisconnect(TestScaffold.java:952)
        at ConnectedVMs.runTests(ConnectedVMs.java:97)
        at TestScaffold.startTests(TestScaffold.java:434)
        at ConnectedVMs.main(ConnectedVMs.java:48)
        at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
        at java.base/java.lang.reflect.Method.invoke(Method.java:578)
        at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:312)
        at java.base/java.lang.Thread.run(Thread.java:1592)

JavaTest Message: Test threw exception: java.lang.RuntimeException
JavaTest Message: shutting down test

result: Failed. Execution failed: `main' threw exception: java.lang.RuntimeException: Non-zero debuggee exitValue: 143