CleanupDirTests.agentvm.conc intermittently fails due to the failing assertion:
'Test results: passed: 8'
but the jt.log files contains:
Test results: passed: 7.

This happens due to TestStats finishedTest() lacking synchronized keyword[1]. The updates to the test counts can happen concurrently.

[1] https://github.com/openjdk/jtreg/blob/34ccc66ec89651637811678a17d3f810b4ac0780/src/share/classes/com/sun/javatest/regtest/report/TestStats.java#L102