ZGC: crash in __memset_evex_unaligned_erms when initializing heap using high values for -XX:ConcGCThreads.

java -XX:+UseZGC -XX:ConcGCThreads=11111210 -version

I suppose we want to exit with an out of memory error instead.

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# SIGSEGV (0xb) at pc=0x00007f20ea96c27a, pid=1926977, tid=1926978
#
# JRE version: (27.0) (fastdebug build )
# Java VM: Java HotSpot(TM) 64-Bit Server VM (fastdebug 27-[...], mixed mode, tiered, compressed class ptrs, z gc, linux-amd64)
# Problematic frame:
# C [libc.so.6+0x16c27a] __memset_evex_unaligned_erms+0x7a
#


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

Current thread (0x00007f20e00cb330): JavaThread "Unknown thread" [_thread_in_vm, id=1926978, stack(0x00007f20e8025000,0x00007f20e8125000) (1024K)]

Stack: [0x00007f20e8025000,0x00007f20e8125000], sp=0x00007f20e8121a68, free space=1010k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C [libc.so.6+0x16c27a] __memset_evex_unaligned_erms+0x7a
V [libjvm.so+0x1d8e046] ZInitializer::ZInitializer(ZBarrierSet*)+0x76 (zInitialize.cpp:64)
V [libjvm.so+0x1d67327] ZCollectedHeap::ZCollectedHeap()+0x37 (zCollectedHeap.cpp:64)
V [libjvm.so+0x1d343aa] ZArguments::create_heap()+0x4a (zArguments.cpp:258)
V [libjvm.so+0x1c199f9] Universe::initialize_heap()+0x29 (universe.cpp:959)
V [libjvm.so+0x1c19b6a] universe_init()+0xfa (universe.cpp:893)
V [libjvm.so+0x1080360] init_globals()+0x50 (init.cpp:138)
V [libjvm.so+0x1bdc007] Threads::create_vm(JavaVMInitArgs*, bool*)+0x367 (threads.cpp:607)
V [libjvm.so+0x124ebe4] JNI_CreateJavaVM+0x54 (jni.cpp:3621)
C [libjli.so+0x3e7f] JavaMain+0x8f (java.c:1506)
C [libjli.so+0x8099] ThreadJavaMain+0x9 (java_md.c:646)

siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x0000000000000000