[8u-dev] Request for enhancement backport approval for CR 8189170 - Add option to disable stack overflow checking in primordial thread for use with JNI_CreateJavaJVM

[David Buck]

Hi!

Please consider the following enhancement for approval:

bug report:
https://bugs.openjdk.java.net/browse/JDK-8189170

This is an important fix that helps improve our interoperability with 
the language runtime for R and possibly other languages as well. There 
are likely other JNI use cases that also benefit from this as well. One 
could even argue that the current behavior is a bug as it is not clear 
at all why the JVM would be justified in assuming that it completely 
"owns" the thread that calls JNI_CreateJavaVM. Either way, this is an 
important and safe fix.

All standard JPRT tests run and passed (hotspot testset). Effectiveness 
of change manually confirmed with dummy JNI invocation test case. The 
change itself is relatively small and very straightforward. It has zero 
impact on JVM processes launched by our own launcher, and will only 
impact JNI programs that use the Invocation API if both the 
UnlockExperimentalVMOptions and DisablePrimordialThreadGuardPages 
options are passed to the JVM. I believe any risk posed by including 
this in JDK 8 is negligible.

Cheers,
-Buck