Currently, `OopHandle::release()` is implemented as follows:
inline void OopHandle::release(OopStorage* storage) {
if (peek() != NULL) {
// Clear the OopHandle first
NativeAccess<>::oop_store(_obj, (oop)NULL);
storage->release(_obj);
}
}
However, peek() returns NULL not only if the oop* `_obj` is NULL, but also when
`_obj` points to a zero oop. In the latter case, the oop* `_obj` will not be
released from the corresponding OopStorage and the slot it occupies will remain
alive forever.
This behavior can be easily triggered with the `LeakTestMinimal.java` test
which is attached to the [JBS
issue](https://bugs.openjdk.java.net/browse/JDK-8273902)(thanks to Oli
Gillespie from the Amazon Profiler team for detecting the issue and providing a
reproducer).
This fix should probably also be downported to jdk17 as quickly as possible.
-------------
Commit messages:
- JDK-8273902: Memory leak in OopStorage due to bug in OopHandle::release()
Changes: https://git.openjdk.java.net/jdk/pull/5549/files
Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5549&range=00
Issue: https://bugs.openjdk.java.net/browse/JDK-8273902
Stats: 4 lines in 2 files changed: 0 ins; 2 del; 2 mod
Patch: https://git.openjdk.java.net/jdk/pull/5549.diff
Fetch: git fetch https://git.openjdk.java.net/jdk pull/5549/head:pull/5549
PR: https://git.openjdk.java.net/jdk/pull/5549
