Crash vmState=0x00000000 running MissingCallerSensitive.java

[pshipton]

https://ci.eclipse.org/openj9/job/Test_openjdk11_j9_sanity.openjdk_ppc64le_linux_xl_Nightly/217
jdk/internal/reflect/CallerSensitive/MissingCallerSensitive.java
ub18-ppcle-1

Diagnostics https://140-211-168-230-openstack.osuosl.org/artifactory/ci-eclipse-openj9/Test/Test_openjdk11_j9_sanity.openjdk_ppc64le_linux_xl_Nightly/217/openjdk_test_output.tar.gz

00:13:49  stderr:
00:13:49  Unhandled exception
00:13:49  Type=Segmentation error vmState=0x00000000
00:13:49  J9Generic_Signal_Number=00000018 Signal_Number=0000000b Error_Value=00000000 Signal_Code=00000001
00:13:49  Handler1=00007AEB926F0690 Handler2=00007AEB9262C100
00:13:49  R0=00007AEB9275F548 R1=00007AEB4D93B660 R2=00007AEB92896F00 R3=0000000000000004
00:13:49  R4=00007AEB6C1B05B0 R5=00007AEB8C496A00 R6=00007AEB1D70E250 R7=0000000000000498
00:13:49  R8=0000000000000018 R9=0000000000000018 R10=0000000000000008 R11=00007AEB6C2C8800
00:13:49  R12=0000000000004400 R13=00007AEB4D9468E0 R14=00007AEAA800D080 R15=00007AEAB0006F00
00:13:49  R16=00007AEB4E170038 R17=FFFFFFFFFFFFFFFF R18=00007AEB4D93BDA8 R19=00007AEB1D70E5D6
00:13:49  R20=00007AEAA8000C50 R21=0000000000000010 R22=00007AEAA800D028 R23=00007AEB93824410
00:13:49  R24=00007AEAB0006F00 R25=00007AEB4D93F240 R26=00007AEB4D93B9A0 R27=00007AEB4D93B890
00:13:49  R28=00007AEB4D93B870 R29=00007AEB6C2B88B0 R30=0000000000000000 R31=0000000000000000
00:13:49  NIP=00007AEB927583E8 MSR=800000010280F033 ORIG_GPR3=00000000000081C8 CTR=00007AEB927635E0
00:13:49  LINK=00007AEB9275F548 XER=0000000000000000 CCR=0000000044004482 SOFTE=0000000000000001
00:13:49  TRAP=0000000000000300 DAR=0000000000000020 dsisr=0000000040000000 RESULT=0000000000000000
00:13:49  FPR0 00007aeaa800d0c8 (f: 2818625792.000000, d: 6.677211e-310)
00:13:49  FPR1 40551ab4a0000000 (f: 2684354560.000000, d: 8.441727e+01)
00:13:49  FPR2 3fe8000000000000 (f: 0.000000, d: 7.500000e-01)
00:13:49  FPR3 004100540045004d (f: 4522061.000000, d: 1.891455e-307)
00:13:49  FPR4 3fce840b4ac4e4d2 (f: 1254417664.000000, d: 2.384047e-01)
00:13:49  FPR5 bfe7154748bef6c8 (f: 1220474624.000000, d: -7.213475e-01)
00:13:49  FPR6 3fe62e42fefa39ef (f: 4277811712.000000, d: 6.931472e-01)
00:13:49  FPR7 3fc526e57720db08 (f: 1998641920.000000, d: 1.652495e-01)
00:13:49  FPR8 bfdffffef20a4123 (f: 4060758272.000000, d: -4.999997e-01)
00:13:49  FPR9 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR10 bfe03f2a28285f5e (f: 673734464.000000, d: -5.077105e-01)
00:13:49  FPR11 3ff0000000000000 (f: 0.000000, d: 1.000000e+00)
00:13:49  FPR12 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR13 0000000000000001 (f: 1.000000, d: 4.940656e-324)
00:13:49  FPR14 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR15 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR16 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR17 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR18 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR19 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR20 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR21 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR22 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR23 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR24 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR25 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR26 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR27 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR28 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR29 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR30 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  FPR31 0000000000000000 (f: 0.000000, d: 0.000000e+00)
00:13:49  Module=/home/jenkins/workspace/Test_openjdk11_j9_sanity.openjdk_ppc64le_linux_xl_Nightly/openjdkbinary/j2sdk-image/lib/default/libj9vm29.so
00:13:49  Module_base_address=00007AEB926B0000
00:13:49  Target=2_90_20201130_358 (Linux 4.15.0-96-generic)
00:13:49  CPU=ppc64le (16 logical CPUs) (0x1fdc70000 RAM)
00:13:49  ----------- Stack Backtrace -----------
00:13:49  (0x00007AEB927583E8 [libj9vm29.so+0xa83e8])
00:13:49  (0x00007AEB927B6134 [libj9vm29.so+0x106134])
00:13:49  (0x00007AEB926C8284 [libj9vm29.so+0x18284])
00:13:49  (0x00007AEB92756110 [libj9vm29.so+0xa6110])
00:13:49  (0x00007AEB9262D508 [libj9prt29.so+0x3d508])
00:13:49  (0x00007AEB927517C4 [libj9vm29.so+0xa17c4])
00:13:49  (0x00007AEB925C1268 [libj9thr29.so+0x11268])
00:13:49  (0x00007AEB937E885C [libpthread.so.0+0x885c])
00:13:49  clone+0x98 (0x00007AEB93699028 [libc.so.6+0x159028])

[pshipton]

@tajila @gacholio fyi

[gacholio]

I'll take a look.

[gacholio]

2 cores, both crash in the exact same place dereferencing NULL somewhere in the bytecode interpreter. Neither java stack is immediately useful.

[gacholio]

Crash appears to be in:

> !j9method 0x00007aeb8c496ed0
J9Method at 0x7aeb8c496ed0 {
  Fields for J9Method:
	0x0: U8* bytecodes = !j9x 0x00007AEB1D70E5D0 // "�"
	0x8: struct J9ConstantPool* constantPool = !j9constantpool 0x00007AEB8C496BE0 (flags = 0x0)
	0x10: void* methodRunAddress = !j9x 0x0000000000000006
	0x18: volatile void* extra = !j9x 0x0000000000000F9B
}
Signature: java/util/concurrent/locks/AbstractQueuedSynchronizer$Node.compareAndSetWaitStatus(II)Z !bytecodes 0x00007AEB8C496ED0
ROM Method: !j9rommethod 0x00007AEB1D70E5BC
Next Method: !j9method 0x00007AEB8C496EF0
> !bytecodes 0x7aeb8c496ed0
  Name: compareAndSetWaitStatus
  Signature: (II)Z
  Access Flags (50010): default final 
  Max Stack: 4
  Argument Count: 3
  Temp Count: 0

    0 getstatic 16 java/util/concurrent/locks/AbstractQueuedSynchronizer$Node.WAITSTATUS Ljava/lang/invoke/VarHandle;
    3 aload0 
    4 iload1 
    5 iload2 
    6 invokevirtual 18 java/lang/invoke/VarHandle.compareAndSet(Ljava/util/concurrent/locks/AbstractQueuedSynchronizer$Node;II)Z
    9 returnZ 

at bytecode 6.

[gacholio]

Full stack:

> !stackslots 0x7aeb8c57da00,0x7aeb8c6f7078,0x7aeb8c6f70c0,0x7AEB1D70E5D6,0x7aeb8c496ed0
<7aeb8c57da00> *** BEGIN STACK WALK, flags = 00400001 walkThread = 0x00007AEB8C57DA00 ***
<7aeb8c57da00> 	ITERATE_O_SLOTS
<7aeb8c57da00> 	RECORD_BYTECODE_PC_OFFSET
<7aeb8c57da00> Initial values: walkSP = 0x00007AEB8C6F7078, PC = 0x00007AEB1D70E5D6, literals = 0x00007AEB8C496ED0, A0 = 0x00007AEB8C6F70C0, j2iFrame = 0x0000000000000000, ELS = 0x00007AEB4C4DBF90, decomp = 0x0000000000000000
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F70A8, sp = 0x00007AEB8C6F7078, pc = 0x00007AEB1D70E5D6, cp = 0x00007AEB8C496BE0, arg0EA = 0x00007AEB8C6F70C0, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/locks/AbstractQueuedSynchronizer$Node.compareAndSetWaitStatus(II)Z !j9method 0x00007AEB8C496ED0
<7aeb8c57da00> 	Bytecode index = 6
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F70C0 for 0x0000000000000003 slots
<7aeb8c57da00> 		I-Slot: a0[0x00007AEB8C6F70C0] = 0x00007AEB6C169438
<7aeb8c57da00> 		I-Slot: a1[0x00007AEB8C6F70B8] = 0x00007AEBFFFFFFFE
<7aeb8c57da00> 		I-Slot: a2[0x00007AEB8C6F70B0] = 0x0000000000000000
<7aeb8c57da00> 	Pending stack starting at 0x00007AEB8C6F7090 for UDATA(0x0000000000000004) slots
<7aeb8c57da00> 		O-Slot: p0[0x00007AEB8C6F7090] = 0x0000000000000000
<7aeb8c57da00> 		O-Slot: p1[0x00007AEB8C6F7088] = 0x00007AEB6C169438
<7aeb8c57da00> 		I-Slot: p2[0x00007AEB8C6F7080] = 0x00007AEBFFFFFFFE
<7aeb8c57da00> 		I-Slot: p3[0x00007AEB8C6F7078] = 0x0000000000000000
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F70D8, sp = 0x00007AEB8C6F70C8, pc = 0x00007AEB1D70D4D4, cp = 0x00007AEB8C491BB0, arg0EA = 0x00007AEB8C6F70E8, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/locks/AbstractQueuedSynchronizer.transferAfterCancelledWait(Ljava/util/concurrent/locks/AbstractQueuedSynchronizer$Node;)Z !j9method 0x00007AEB8C491A90
<7aeb8c57da00> 	Bytecode index = 4
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F70E8 for 0x0000000000000002 slots
<7aeb8c57da00> 		O-Slot: a0[0x00007AEB8C6F70E8] = 0x00007AEB6C0E69E8
<7aeb8c57da00> 		O-Slot: a1[0x00007AEB8C6F70E0] = 0x00007AEB6C169438
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F7100, sp = 0x00007AEB8C6F70F0, pc = 0x00007AEB1D7ABD8F, cp = 0x00007AEB8C6ACA90, arg0EA = 0x00007AEB8C6F7160, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/locks/AbstractQueuedSynchronizer$ConditionObject.awaitNanos(J)J !j9method 0x00007AEB8C6AD188
<7aeb8c57da00> 	Bytecode index = 67
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F7160 for 0x000000000000000C slots
<7aeb8c57da00> 		O-Slot: a0[0x00007AEB8C6F7160] = 0x00007AEB6C0E68F0
<7aeb8c57da00> 		I-Slot: a1[0x00007AEB8C6F7158] = 0x00007AEB8BEE2150
<7aeb8c57da00> 		I-Slot: a2[0x00007AEB8C6F7150] = 0xFFFFFFFFFF207BC5
<7aeb8c57da00> 		I-Slot: t3[0x00007AEB8C6F7148] = 0x00007AEB8C6F71BA
<7aeb8c57da00> 		I-Slot: t4[0x00007AEB8C6F7140] = 0x00443F8D6AD55C2C
<7aeb8c57da00> 		I-Slot: t5[0x00007AEB8C6F7138] = 0x00007AEB8C6AA068
<7aeb8c57da00> 		I-Slot: t6[0x00007AEB8C6F7130] = 0x0000000DF72EB444
<7aeb8c57da00> 		O-Slot: t7[0x00007AEB8C6F7128] = 0x00007AEB6C169438
<7aeb8c57da00> 		I-Slot: t8[0x00007AEB8C6F7120] = 0x0000000000000001
<7aeb8c57da00> 		I-Slot: t9[0x00007AEB8C6F7118] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t10[0x00007AEB8C6F7110] = 0x00007AEB1D96AEDC
<7aeb8c57da00> 		I-Slot: t11[0x00007AEB8C6F7108] = 0x00007AEB8C6F31A0
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F7178, sp = 0x00007AEB8C6F7168, pc = 0x00007AEB1D9695D6, cp = 0x00007AEB8C6AA6F0, arg0EA = 0x00007AEB8C6F71B8, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/ScheduledThreadPoolExecutor$DelayedWorkQueue.take()Ljava/util/concurrent/RunnableScheduledFuture; !j9method 0x00007AEB8C6AA068
<7aeb8c57da00> 	Bytecode index = 126
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F71B8 for 0x0000000000000008 slots
<7aeb8c57da00> 		O-Slot: a0[0x00007AEB8C6F71B8] = 0x00007AEB6C0E6918
<7aeb8c57da00> 		O-Slot: t1[0x00007AEB8C6F71B0] = 0x00007AEB6C0E6950
<7aeb8c57da00> 		I-Slot: t2[0x00007AEB8C6F71A8] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t3[0x00007AEB8C6F71A0] = 0x00007AEB8C6AA208
<7aeb8c57da00> 		I-Slot: t4[0x00007AEB8C6F7198] = 0x0000000DF72EB444
<7aeb8c57da00> 		O-Slot: t5[0x00007AEB8C6F7190] = 0x00007AEB6C169350
<7aeb8c57da00> 		I-Slot: t6[0x00007AEB8C6F7188] = 0x00007AEB8C6F4230
<7aeb8c57da00> 		I-Slot: t7[0x00007AEB8C6F7180] = 0x00007AEB8BEE2008
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F71D0, sp = 0x00007AEB8C6F71C0, pc = 0x00007AEB1D969D25, cp = 0x00007AEB8C6AA6F0, arg0EA = 0x00007AEB8C6F71D8, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/ScheduledThreadPoolExecutor$DelayedWorkQueue.take()Ljava/lang/Object; !j9method 0x00007AEB8C6AA208
<7aeb8c57da00> 	Bytecode index = 1
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F71D8 for 0x0000000000000001 slots
<7aeb8c57da00> 		I-Slot: a0[0x00007AEB8C6F71D8] = 0x00007AEB8BE166D8
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F71F0, sp = 0x00007AEB8C6F71E0, pc = 0x00007AEB1D7A4F7D, cp = 0x00007AEB8C6A5DC0, arg0EA = 0x00007AEB8C6F7220, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/ThreadPoolExecutor.getTask()Ljava/lang/Runnable; !j9method 0x00007AEB8C6A6B30
<7aeb8c57da00> 	Bytecode index = 149
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F7220 for 0x0000000000000006 slots
<7aeb8c57da00> 		O-Slot: a0[0x00007AEB8C6F7220] = 0x00007AEB6C0E6968
<7aeb8c57da00> 		I-Slot: t1[0x00007AEB8C6F7218] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t2[0x00007AEB8C6F7210] = 0x00007AEBE0000001
<7aeb8c57da00> 		I-Slot: t3[0x00007AEB8C6F7208] = 0x00007AEB00000001
<7aeb8c57da00> 		I-Slot: t4[0x00007AEB8C6F7200] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t5[0x00007AEB8C6F71F8] = 0x0000000000000001
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F7238, sp = 0x00007AEB8C6F7228, pc = 0x00007AEB1D7A502E, cp = 0x00007AEB8C6A5DC0, arg0EA = 0x00007AEB8C6F7278, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/ThreadPoolExecutor.runWorker(Ljava/util/concurrent/ThreadPoolExecutor$Worker;)V !j9method 0x00007AEB8C6A6B50
<7aeb8c57da00> 	Bytecode index = 26
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F7278 for 0x0000000000000008 slots
<7aeb8c57da00> 		O-Slot: a0[0x00007AEB8C6F7278] = 0x00007AEB6C0E6968
<7aeb8c57da00> 		O-Slot: a1[0x00007AEB8C6F7270] = 0x00007AEB6C169470
<7aeb8c57da00> 		O-Slot: t2[0x00007AEB8C6F7268] = 0x00007AEB6C169350
<7aeb8c57da00> 		I-Slot: t3[0x00007AEB8C6F7260] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t4[0x00007AEB8C6F7258] = 0x00007AEB00000001
<7aeb8c57da00> 		I-Slot: t5[0x00007AEB8C6F7250] = 0x0000000000000000
<7aeb8c57da00> 		I-Slot: t6[0x00007AEB8C6F7248] = 0x00007AEB8C6A6B50
<7aeb8c57da00> 		I-Slot: t7[0x00007AEB8C6F7240] = 0x00007AEB6C270338
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F7290, sp = 0x00007AEB8C6F7280, pc = 0x00007AEB1D7C6AC5, cp = 0x00007AEB8C6F4010, arg0EA = 0x00007AEB8C6F7298, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/util/concurrent/ThreadPoolExecutor$Worker.run()V !j9method 0x00007AEB8C6F41D0
<7aeb8c57da00> 	Bytecode index = 5
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F7298 for 0x0000000000000001 slots
<7aeb8c57da00> 		I-Slot: a0[0x00007AEB8C6F7298] = 0x00007AEB8BEE2008
<7aeb8c57da00> Bytecode frame: bp = 0x00007AEB8C6F72B0, sp = 0x00007AEB8C6F72A0, pc = 0x00007AEB1D49DF59, cp = 0x00007AEB8C357090, arg0EA = 0x00007AEB8C6F72B8, flags = 0x0000000000000000
<7aeb8c57da00> 	Method: java/lang/Thread.run()V !j9method 0x00007AEB8C358728
<7aeb8c57da00> 	Bytecode index = 13
<7aeb8c57da00> 	Using local mapper
<7aeb8c57da00> 	Locals starting at 0x00007AEB8C6F72B8 for 0x0000000000000001 slots
<7aeb8c57da00> 		I-Slot: a0[0x00007AEB8C6F72B8] = 0x00007AEB8BEE2150
<7aeb8c57da00> JNI call-in frame: bp = 0x00007AEB8C6F72E0, sp = 0x00007AEB8C6F72C0, pc = 0x00007AEB9285CA58, cp = 0x0000000000000000, arg0EA = 0x00007AEB8C6F72E0, flags = 0x0000000000000000
<7aeb8c57da00> 	New ELS = 0x0000000000000000
<7aeb8c57da00> JNI native method frame: bp = 0x00007AEB8C6F7308, sp = 0x00007AEB8C6F72E8, pc = 0x0000000000000007, cp = 0x0000000000000000, arg0EA = 0x00007AEB8C6F7308, flags = 0x0000000000000000
<7aeb8c57da00> <end of stack>
<7aeb8c57da00> *** END STACK WALK (rc = NONE) ***

[gacholio]

The WAITSTATUS static appears valid:

> !j9object 0x00007AEB6C2B88B0
!J9Object 0x00007AEB6C2B88B0 {
	struct J9Class* clazz = !j9class 0x7AEB8C493B00 // java/lang/invoke/InstanceFieldVarHandle
	Object flags = 0x00000000;
	J lockword = 0x0000000000000000 (offset = 0) (java/lang/Object) <hidden>
	[Ljava/lang/invoke/MethodHandle; handleTable = !fj9object 0x7aeb6c31bae8 (offset = 8) (java/lang/invoke/VarHandle)
	Ljava/lang/Class; fieldType = !fj9object 0x7aeb6c000f18 (offset = 16) (java/lang/invoke/VarHandle)
	[Ljava/lang/Class; coordinateTypes = !fj9object 0x7aeb6c31bbf0 (offset = 24) (java/lang/invoke/VarHandle)
	I modifiers = 0x00300040 (offset = 32) (java/lang/invoke/VarHandle)
	J vmslot = 0x0000000000000030 (offset = 40) (java/lang/invoke/FieldVarHandle)
	Ljava/lang/String; fieldName = !fj9object 0x7aeb6c2c8598 (offset = 48) (java/lang/invoke/FieldVarHandle)
	Ljava/lang/Class; definingClass = !fj9object 0x7aeb6c03cce8 (offset = 56) (java/lang/invoke/FieldVarHandle)
}

[gacholio]

The stack is modified by the VarHandle implementation code:

0x7AEB8C6F7070 :  00007aeb6c2b88b0 0000000000000000 [ ..+l.z.......... ] 
0x7AEB8C6F7080 :  00007aebfffffffe 00007aeb6c169438 [ .....z..8..l.z.. ] 
0x7AEB8C6F7090 :  000000000000000

The VarHandle is pushed onto the stack, and it's old stack slot is overwritten with a MethodHandle (somehow 0 in this case, which is no doubt the cause of the crash).

[gacholio]

I expect the actual crash occurs transitioning to the MH interpreter due to the NULL MH. The code which set the slot to NULL is:

https://github.com/eclipse/openj9/blob/master/runtime/vm/BytecodeInterpreter.hpp#L8469-L8553

[gacholio]

@babsingh There must be a timing hole somewhere in the caching mechanism, though I don't see it. This might also be related to weak memory ordering on PPC. I notice the callSiteType variable has been randomly marked volatile, which might trick the compiler into doing something stupid.

[pshipton]

100x grinder https://ci.eclipse.org/openj9/job/Grinder/1231/

[gacholio]

Grinder appears to be failing for an unrelated reason:

14:36:53  Error: Cannot find file: /home/jenkins/workspace/Grinder_iteration_3/openjdk-tests/TKG/../openjdk/openjdk-jdk/jdk/internal/reflect/CallerSensitive/MissingCallerSensitive.java

[pshipton]

Ya, I messed up the test name.
100x (25x on 4 machines) grinder https://ci.eclipse.org/openj9/job/Grinder/1232/ - passed