During an internal test on Linux we sometimes crash the JVM. It is probably related to opening and closing many datagram sockets. Here is the dump from the JVM:

#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
#  SIGSEGV (0xb) at pc=0xf162655c, pid=14107, tid=3450862512
#
# Java VM: Java HotSpot(TM) Server VM (1.5.0_12-b04 mixed mode)
# Problematic frame:
# v  ~BufferBlob::jni_fast_GetIntField
#
# Can not save log file, dump to screen..
#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
#  SIGSEGV (0xb) at pc=0xf162655c, pid=14107, tid=3450862512
#
# Java VM: Java HotSpot(TM) Server VM (1.5.0_12-b04 mixed mode)
# Problematic frame:
# v  ~BufferBlob::jni_fast_GetIntField
#

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

Current thread (0x081040e8):  JavaThread "Finalizer" daemon [_thread_in_native, id=14116]

siginfo:si_signo=11, si_errno=0, si_code=1, si_addr=0x00000000

Registers:
EAX=0x00000022, EBX=0xcbe47304, ECX=0x00000026, EDX=0x00000000
ESP=0xcdafe890, EBP=0xcdafe8ac, ESI=0x081041a8, EDI=0x081040e8
EIP=0xf162655c, CR2=0x00000000, EFLAGS=0x00010246

Top of Stack: (sp=0xcdafe890)
0xcdafe890:   cbe444d3 081041a8 00000000 00000022
0xcdafe8a0:   cdafe8cc cdafe8d4 cbe47304 cdafe8cc
0xcdafe8b0:   cbe43ee9 081041a8 00000000 ce546f20
0xcdafe8c0:   cdafe8d4 ce546fa8 ce546fa0 cdafe8fc
0xcdafe8d0:   f15eb898 081041a8 cdafe904 00000000
0xcdafe8e0:   cdafe8e0 00000000 cdafe90c ce547b18
0xcdafe8f0:   00000000 ce546fa8 cdafe90c cdafe92c
0xcdafe900:   f15e5b6b ce547a88 f15e96b9 00000000 

Instructions: (pc=0xf162655c)
0xf162654c:   00 00 00 8b c1 83 e0 01 8b 54 04 08 8b 44 24 0c
0xf162655c:   8b 12 c1 e8 02 8b 04 02 8b d0 81 f2 f4 96 bb f7 

Stack: [0xcda7f000,0xcdb00000),  sp=0xcdafe890,  free space=510k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
v  ~BufferBlob::jni_fast_GetIntField
C  [libnio.so+0x3ee9]  Java_sun_nio_ch_FileDispatcher_preClose0+0x29
j  sun.nio.ch.FileDispatcher.preClose0(Ljava/io/FileDescriptor;)V+0
j  sun.nio.ch.DatagramDispatcher.preClose(Ljava/io/FileDescriptor;)V+1
j  sun.nio.ch.DatagramChannelImpl.implCloseSelectableChannel()V+14
j  java.nio.channels.spi.AbstractSelectableChannel.implCloseChannel()V+1
C  [libnio.so+0x3ee9]  Java_sun_nio_ch_FileDispatcher_preClose0+0x29
j  sun.nio.ch.FileDispatcher.preClose0(Ljava/io/FileDescriptor;)V+0
j  sun.nio.ch.DatagramDispatcher.preClose(Ljava/io/FileDescriptor;)V+1
j  sun.nio.ch.DatagramChannelImpl.implCloseSelectableChannel()V+14
j  java.nio.channels.spi.AbstractSelectableChannel.implCloseChannel()V+1
j  java.nio.channels.spi.AbstractInterruptibleChannel.close()V+23
j  sun.nio.ch.DatagramChannelImpl.finalize()V+1
v  ~StubRoutines::call_stub
V  [libjvm.so+0x267d7c]
V  [libjvm.so+0x437618]
V  [libjvm.so+0x267baf]
V  [libjvm.so+0x292a33]
V  [libjvm.so+0x278db4]
C  [libjava.so+0xb3fe]  Java_java_lang_ref_Finalizer_invokeFinalizeMethod+0x6e
j  java.lang.ref.Finalizer.invokeFinalizeMethod(Ljava/lang/Object;)V+0
j  java.lang.ref.Finalizer.runFinalizer()V+45
j  java.lang.ref.Finalizer.access$100(Ljava/lang/ref/Finalizer;)V+1
j  java.lang.ref.Finalizer$FinalizerThread.run()V+11
v  ~StubRoutines::call_stub
V  [libjvm.so+0x267d7c]
V  [libjvm.so+0x437618]
V  [libjvm.so+0x2675d5]
V  [libjvm.so+0x26766e]
V  [libjvm.so+0x2df635]
V  [libjvm.so+0x4d7d13]
V  [libjvm.so+0x438228]
C  [libpthread.so.0+0x5371]

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
j  sun.nio.ch.FileDispatcher.preClose0(Ljava/io/FileDescriptor;)V+0
j  sun.nio.ch.DatagramDispatcher.preClose(Ljava/io/FileDescriptor;)V+1
j  sun.nio.ch.DatagramChannelImpl.implCloseSelectableChannel()V+14
j  java.nio.channels.spi.AbstractSelectableChannel.implCloseChannel()V+1
j  java.nio.channels.spi.AbstractInterruptibleChannel.close()V+23
j  sun.nio.ch.DatagramChannelImpl.finalize()V+1
v  ~StubRoutines::call_stub
j  java.lang.ref.Finalizer.invokeFinalizeMethod(Ljava/lang/Object;)V+0
j  java.lang.ref.Finalizer.runFinalizer()V+45
j  java.lang.ref.Finalizer.access$100(Ljava/lang/ref/Finalizer;)V+1
j  java.lang.ref.Finalizer$FinalizerThread.run()V+11
v  ~StubRoutines::call_stub

---------------  P R O C E S S  ---------------

Java Threads: ( => current thread )
  0x0812b298 JavaThread "Thread-318" [_thread_in_native, id=15839]

... a lot of threads, so no place in the bug Description window...
(see comments)

  0xcc459ac0 JavaThread "Job_Executor0" daemon [_thread_in_native, id=14127]
  0xcc428348 JavaThread "RMI TCP Accept-19009" daemon [_thread_in_native, id=14124]
  0xcc424d30 JavaThread "RMI TCP Accept-0" daemon [_thread_in_native, id=14123]
  0xcc424760 JavaThread "Timer-0" daemon [_thread_blocked, id=14122]
  0x081125f8 JavaThread "Low Memory Detector" daemon [_thread_blocked, id=14121]
  0x08111120 JavaThread "CompilerThread1" daemon [_thread_in_native, id=14120]
  0x08110070 JavaThread "CompilerThread0" daemon [_thread_in_native, id=14119]
  0x0810eef0 JavaThread "AdapterThread" daemon [_thread_blocked, id=14118]
  0x0810e038 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=14117]
#
# Java VM: Java HotSpot(TM) Server VM (1.5.0_12-b04 mixed mode)
# Problematic frame:
# v  ~BufferBlob::jni_fast_GetIntField
#
# Can not save log file, dump to screen..
#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
#  SIGSEGV (0xb) at pc=0xf162655c, pid=14107, tid=3450862512
#
# Java VM: Java HotSpot(TM) Server VM (1.5.0_12-b04 mixed mode)
# Problematic frame:
# v  ~BufferBlob::jni_fast_GetIntField
#

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

Current thread (0x081040e8):  JavaThread "Finalizer" daemon [_thread_in_native, id=14116]

siginfo:si_signo=11, si_errno=0, si_code=1, si_addr=0x00000000

Registers:
EAX=0x00000022, EBX=0xcbe47304, ECX=0x00000026, EDX=0x00000000
ESP=0xcdafe890, EBP=0xcdafe8ac, ESI=0x081041a8, EDI=0x081040e8
EIP=0xf162655c, CR2=0x00000000, EFLAGS=0x00010246

Top of Stack: (sp=0xcdafe890)
0xcdafe890:   cbe444d3 081041a8 00000000 00000022
0xcdafe8a0:   cdafe8cc cdafe8d4 cbe47304 cdafe8cc
0xcdafe8b0:   cbe43ee9 081041a8 00000000 ce546f20
0xcdafe8c0:   cdafe8d4 ce546fa8 ce546fa0 cdafe8fc
0xcdafe8d0:   f15eb898 081041a8 cdafe904 00000000
0xcdafe8e0:   cdafe8e0 00000000 cdafe90c ce547b18
0xcdafe8f0:   00000000 ce546fa8 cdafe90c cdafe92c
0xcdafe900:   f15e5b6b ce547a88 f15e96b9 00000000 

Instructions: (pc=0xf162655c)
0xf162654c:   00 00 00 8b c1 83 e0 01 8b 54 04 08 8b 44 24 0c
0xf162655c:   8b 12 c1 e8 02 8b 04 02 8b d0 81 f2 f4 96 bb f7 

Stack: [0xcda7f000,0xcdb00000),  sp=0xcdafe890,  free space=510k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
v  ~BufferBlob::jni_fast_GetIntField
C  [libnio.so+0x3ee9]  Java_sun_nio_ch_FileDispatcher_preClose0+0x29
j  sun.nio.ch.FileDispatcher.preClose0(Ljava/io/FileDescriptor;)V+0
j  sun.nio.ch.DatagramDispatcher.preClose(Ljava/io/FileDescriptor;)V+1
j  sun.nio.ch.DatagramChannelImpl.implCloseSelectableChannel()V+14
j  java.nio.channels.spi.AbstractSelectableChannel.implCloseChannel()V+1
j  java.nio.channels.spi.AbstractInterruptibleChannel.close()V+23
j  sun.nio.ch.DatagramChannelImpl.finalize()V+1
v  ~StubRoutines::call_stub
V  [libjvm.so+0x267d7c]
V  [libjvm.so+0x437618]
V  [libjvm.so+0x267baf]
V  [libjvm.so+0x292a33]
V  [libjvm.so+0x278db4]
C  [libjava.so+0xb3fe]  Java_java_lang_ref_Finalizer_invokeFinalizeMethod+0x6e
j  java.lang.ref.Finalizer.invokeFinalizeMethod(Ljava/lang/Object;)V+0
j  java.lang.ref.Finalizer.runFinalizer()V+45
j  java.lang.ref.Finalizer.access$100(Ljava/lang/ref/Finalizer;)V+1
j  java.lang.ref.Finalizer$FinalizerThread.run()V+11
v  ~StubRoutines::call_stub
V  [libjvm.so+0x267d7c]
V  [libjvm.so+0x437618]
V  [libjvm.so+0x2675d5]
V  [libjvm.so+0x26766e]
V  [libjvm.so+0x2df635]
V  [libjvm.so+0x4d7d13]
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