On Thu, 10 Apr 2025 05:50:23 GMT, Serguei Spitsyn <sspit...@openjdk.org> wrote:
>> As noted in [JDK-8352088](https://bugs.openjdk.org/browse/JDK-8352088), >> JVMTI `GetThreadGroupChildren` does an upcall to java. This results in >> a`ClassPrepare` event the first time it does this, and these events can >> cause problems (deadlocks) for the debugger or debug agent. The >> [JDK-8352088](https://bugs.openjdk.org/browse/JDK-8352088) was fixed to get >> rid of class loading during Java upcall from `GetThreadGroupChildren`. >> However, some other events can be generated as well. It is more safe to >> disable all JVMTI events during debugger-related upcalls originated by JVMTI. >> The `ClassPrepare` events are important for the debug agent. So, an assert >> was added into `ClassPrepare` event generation to make sure there are no >> attempts to post this event during upcalls. >> Some specific implementation details can be added to the first PR comment. >> >> Testing: >> - Verified with the test >> `jdk/com/sun/jdi/EarlyThreadGroupChildrenTest.java` that was added with the >> fix of [JDK-8352088](https://bugs.openjdk.org/browse/JDK-8352088): >> - the assert described above is fired if the fix of JDK-8352088 is removed >> - the test is passed without if the fix of JDK-8352088 is removed and the >> assert is removed >> - Ran mach5 tiers 1-6 > > Serguei Spitsyn has updated the pull request incrementally with one > additional commit since the last revision: > > review: minor tweak in two similar comments I've pushed a minor update to fix a build time error for minimal VM. ------------- PR Comment: https://git.openjdk.org/jdk/pull/24539#issuecomment-2794701655
