The following test failed in the JDK16 CI:

applications/kitchensink/Kitchensink24HStress.java

Here's the crashing thread's stack:

--------------- T H R E A D ---------------

Current thread (0x00007f9140000ca0): GCTaskThread "GC Thread#1" [stack: 0x00007f91490fc000,0x00007f91491fc000] [id=11455]

Stack: [0x00007f91490fc000,0x00007f91491fc000], sp=0x00007f91491f9710, free space=1013k
Native frames: (J=compiled Java code, A=aot compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [libjvm.so+0x685bbb] G1ParScanThreadState::copy_to_survivor_space(G1HeapRegionAttr, oopDesc*, markWord)+0x4b
V [libjvm.so+0x6a2ccc] G1ParCopyClosure<(G1Barrier)0, (G1Mark)1>::do_oop(oopDesc**)+0x15c
V [libjvm.so+0x6fda3d] HandleArea::oops_do(OopClosure*)+0x5d
V [libjvm.so+0xceb348] JavaThread::oops_do(OopClosure*, CodeBlobClosure*)+0x58
V [libjvm.so+0xcf19e7] Threads::possibly_parallel_oops_do(bool, OopClosure*, CodeBlobClosure*)+0x187
V [libjvm.so+0x6a47f3] G1RootProcessor::process_java_roots(G1RootClosures*, G1GCPhaseTimes*, unsigned int)+0x73
V [libjvm.so+0x6a53f3] G1RootProcessor::evacuate_roots(G1ParScanThreadState*, unsigned int)+0x63
V [libjvm.so+0x641a92] G1EvacuateRegionsTask::scan_roots(G1ParScanThreadState*, unsigned int)+0x22
V [libjvm.so+0x6424d9] G1EvacuateRegionsBaseTask::work(unsigned int)+0x99
V [libjvm.so+0xd8e21d] GangWorker::loop()+0x4d
V [libjvm.so+0xcf325d] Thread::call_run()+0xfd
V [libjvm.so+0xb468a7] thread_native_entry(Thread*)+0xe7


siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x0000000901487108