[jdk17u-dev] RFR: 8268364: jmethod clearing should be done during unloading

[Goetz Lindenmaier]

On Mon, 2 Sep 2024 10:31:10 GMT, Kerem Kat <duke at openjdk.org> wrote:

> Clean backport of [8268364](https://bugs.openjdk.org/browse/JDK-8268364).
> 
> It fixes crashes when accessing jmethodIDs of a class being unloaded.
> 
> Here is the reproducer that crashes JVM in ~1 second without the patch, but works fine with it: [gist](https://gist.github.com/krk/a0800bac5bc5a01709be85637285a965).
> 
> This fix also resolves the issue reported at https://github.com/async-profiler/async-profiler/issues/974 for Java 17.
> 
> **Additional testing**: release and fastdebug with `JTREG_KEYWORDS="!headful & !external-dep & !printer"`, no new test failures with the patch.
> 
> To run the repro:
> 
> 
> javac Main.java
> gcc -shared -I"$JAVA_HOME/include" -I"$JAVA_HOME/include/linux" -fPIC repro.cpp -orepro.so
> 
> java -agentpath:"$(pwd)/repro.so" -Xmx100m Main

Hi @krk,
thanks for contributing.
Please provide a useful fix request comment. See also https://wiki.openjdk.org/display/JDKUpdates/How+to+contribute+or+backport+a+fix
Removed the fix-request tag in the meantime.
Please also check the GHA check failures. If they are unrealated to your PR, you can tell in a comment that you want to proceed anyways, else I assume you did not check them.

-------------

PR Comment: https://git.openjdk.org/jdk17u-dev/pull/2839#issuecomment-2336648840