The can_support_virtual_thread was initially implemented as an onload capability. It is why this capability does not work for the agents loaded into running VM. The fix is to move it from `onload` to `always`capabilities list.
Testing: New test is added: VirtualStartThreadTest. TBD: mach5 jvmti, jdi and tier1-6 tests. ------------- Commit messages: - simplified VirtualThreadStartTest - 8296323: JVMTI can_support_virtual_threads not available for agents loaded into running VM Changes: https://git.openjdk.org/jdk/pull/11246/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11246&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8296323 Stats: 157 lines in 4 files changed: 153 ins; 2 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/11246.diff Fetch: git fetch https://git.openjdk.org/jdk pull/11246/head:pull/11246 PR: https://git.openjdk.org/jdk/pull/11246
