When running Intellij IDEA, I get:

# SIGSEGV (0xb) at pc=0x0000ffffa0828c20, pid=16152, tid=16261
#
# JRE version: OpenJDK Runtime Environment (14.0) (build 14-internal+0-adhoc.aph.jdk-scratchregs)
# Java VM: OpenJDK 64-Bit Server VM (14-internal+0-adhoc.aph.jdk-scratchregs, mixed mode, sharing, tiered, compressed oops, shenandoah gc, linux-aarch64)
# Problematic frame:
# v ~BufferBlob::jni_fast_GetLongField

This is caused by a bug in ShenandoahBarrierSetAssembler::try_resolve_jobject_in_native, which assumes that rthread contains a pointer to the current thread. It doesn't, so we get a crash. Intel x86 code for the same thing is correct.