Seen in our newly deployed macOS 26 testing.

Test: (langtools) tools/javac/annotations/repeatingAnnotations/combo/DeprecatedAnnoCombo.java (macosx-aarch64)

There is a communication issue between the main VM and an AgentVM.

Agent[1] log shows:

[2025-10-28 01:45:55,286] AgentServer[1]: tools/javac/annotations/repeatingAnnotations/brokenTypeAnnoContainer/BrokenTypeAnnoContainer.java: finished compilation
[2025-10-28 01:53:55,299] AgentServer[1]: Exiting

Main agent.trace shows:

[2025-10-28 01:45:55,293]: POOL: Reusing Agent[1]
[2025-10-28 01:45:55,297]: #1/4 POOL: get agent for:
[2025-10-28 01:45:55,297]: #2/4 directory: /System/Volumes/Data/mesos/work_dir/slaves/526fbd26-20de-495c-9a19-a04adc16f7d1-S11755/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/ba1597a7-ea3c-4d2b-8094-fd2daa28f0a6/runs/5e679ebc-bbd3-4b2a-b6be-dc1454cd689c/testoutput/test-support/jtreg_open_test_langtools_tier1/scratch/0
[2025-10-28 01:45:55,297]: #3/4 JDK: /System/Volumes/Data/mesos/work_dir/jib-master/install/jdk-26+22-2219/macosx-aarch64.jdk/jdk-26.jdk/Contents/Home
[2025-10-28 01:45:55,297]: #4/4 VM options: [-classpath, /System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/8.1/1/bundles/jtreg-8.1+1.zip/jtreg/lib/jtreg.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/8.1/1/bundles/jtreg-8.1+1.zip/jtreg/lib/junit-platform-console-standalone-1.13.4.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/8.1/1/bundles/jtreg-8.1+1.zip/jtreg/lib/testng-7.3.0.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/8.1/1/bundles/jtreg-8.1+1.zip/jtreg/lib/jcommander-1.82.jar:/System/Volumes/Data/mesos/work_dir/jib-master/install/jtreg/8.1/1/bundles/jtreg-8.1+1.zip/jtreg/lib/guice-5.1.0.jar, -Xmx768m, -XX:MaxRAMPercentage=6.25, -Dtest.boot.jdk=/System/Volumes/Data/mesos/work_dir/jib-master/install/jdk/25/37/bundles/macos-aarch64/jdk-25_macos-aarch64_bin.tar.gz/jdk-25.jdk/Contents/Home, -Djava.io.tmpdir=/System/Volumes/Data/mesos/work_dir/slaves/526fbd26-20de-495c-9a19-a04adc16f7d1-S11755/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/ba1597a7-ea3c-4d2b-8094-fd2daa28f0a6/runs/5e679ebc-bbd3-4b2a-b6be-dc1454cd689c/testoutput/test-support/jtreg_open_test_langtools_tier1/tmp, -ea, -esa, --patch-module, java.base=/System/Volumes/Data/mesos/work_dir/slaves/526fbd26-20de-495c-9a19-a04adc16f7d1-S11755/frameworks/1735e8a2-a1db-478c-8104-60c8b0af87dd-0196/executors/ba1597a7-ea3c-4d2b-8094-fd2daa28f0a6/runs/5e679ebc-bbd3-4b2a-b6be-dc1454cd689c/testoutput/test-support/jtreg_open_test_langtools_tier1/patches/java.base]
...
[2025-10-28 01:53:55,297] Agent[1]: Closing...
[2025-10-28 01:53:55,306] Agent[1]: stderr: java.net.SocketTimeoutException: Read timed out
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/sun.nio.ch.NioSocketImpl.timedRead(NioSocketImpl.java:277)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/sun.nio.ch.NioSocketImpl.implRead(NioSocketImpl.java:302)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/sun.nio.ch.NioSocketImpl.read(NioSocketImpl.java:354)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/sun.nio.ch.NioSocketImpl$1.read(NioSocketImpl.java:798)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.net.Socket$SocketInputStream.implRead(Socket.java:981)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.net.Socket$SocketInputStream.read(Socket.java:971)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:289)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.BufferedInputStream.read1(BufferedInputStream.java:330)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:388)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.DataInputStream.readFully(DataInputStream.java:213)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.DataInputStream.readUnsignedShort(DataInputStream.java:346)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.DataInputStream.readUTF(DataInputStream.java:580)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at java.base/java.io.DataInputStream.readUTF(DataInputStream.java:555)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at com.sun.javatest.regtest.agent.AgentServer.readList(AgentServer.java:334)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at com.sun.javatest.regtest.agent.AgentServer.doCompile(AgentServer.java:270)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at com.sun.javatest.regtest.agent.AgentServer.run(AgentServer.java:241)
[2025-10-28 01:53:55,308] Agent[1]: stderr: at com.sun.javatest.regtest.agent.AgentServer.main(AgentServer.java:71)
[2025-10-28 01:53:55,339] Agent[1]: Closed