This is a clean 21 backport of the 22 fix: [JDK-8300051](https://bugs.openjdk.org/browse/JDK-8300051): assert(JvmtiEnvBase::environments_might_exist()) failed: to enter event controller, JVM TI environments must exist
Testing: - TBD: mach5 tiers 1-5 ------------- Commit messages: - Backport 783de32b6af4383b5ba71b91c307a5dddd0dae13 Changes: https://git.openjdk.org/jdk21/pull/143/files Webrev: https://webrevs.openjdk.org/?repo=jdk21&pr=143&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8300051 Stats: 26 lines in 2 files changed: 14 ins; 12 del; 0 mod Patch: https://git.openjdk.org/jdk21/pull/143.diff Fetch: git fetch https://git.openjdk.org/jdk21.git pull/143/head:pull/143 PR: https://git.openjdk.org/jdk21/pull/143