Deadlock problem between unregisterClassLoader and normal classloader usage --------------------------------------------------------------------------- Key: JBCL-26 URL: https://jira.jboss.org/jira/browse/JBCL-26 Project: JBoss ClassLoader Issue Type: Bug Components: ClassLoaderSystem Affects Versions: JBossCL.2.0.0.Beta12 Reporter: Adrian Brock Assignee: Adrian Brock Fix For: JBossCL.2.0.0.CR1 There's a deadlock problem between ClassLoaderDomain.unregisterClassLoader() and normal classloader usage, as shown by this thread dump during SHUTDOWN: Found one Java-level deadlock: ============================= "JBoss Shutdown Hook": waiting to lock monitor 0x09314444 (object 0xaef03488, a org.jboss.classloader.spi.base.BaseClassLoader), which is held by "main" "main": waiting to lock monitor 0x09314484 (object 0xaef029b8, a org.jboss.classloader.spi.ClassLoaderDomain), which is held by "JBoss Shutdown Hook" Java stack information for the threads listed above: =================================================== "JBoss Shutdown Hook": at org.jboss.mx.server.MBeanServerImpl.unregisterMBean(MBeanServerImpl.java:395) at org.jboss.classloader.spi.ClassLoaderDomain.unregisterClassLoaderMBean(ClassLoaderDomain.java:685) at org.jboss.classloader.spi.ClassLoaderDomain.beforeUnregisterClassLoader(ClassLoaderDomain.java:643) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.unregisterClassLoader(BaseClassLoaderDomain.java:1236) - locked <0xaef029b8> (a org.jboss.classloader.spi.ClassLoaderDomain) at org.jboss.classloader.spi.base.BaseClassLoaderSystem.unregisterClassLoaderPolicy(BaseClassLoaderSystem.java:147) at org.jboss.classloader.spi.ClassLoaderSystem.unregisterClassLoaderPolicy(ClassLoaderSystem.java:470) at org.jboss.classloading.spi.dependency.policy.ClassLoaderPolicyModule.removeClassLoader(ClassLoaderPolicyModule.java:147) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.jboss.reflect.plugins.introspection.ReflectionUtils.invoke(ReflectionUtils.java:56) at org.jboss.reflect.plugins.introspection.ReflectMethodInfoImpl.invoke(ReflectMethodInfoImpl.java:110) at org.jboss.joinpoint.plugins.BasicMethodJoinPoint.dispatch(BasicMethodJoinPoint.java:66) at org.jboss.beans.info.plugins.AbstractBeanInfo.invoke(AbstractBeanInfo.java:300) at org.jboss.kernel.plugins.dependency.AbstractKernelControllerContext.invoke(AbstractKernelControllerContext.java:279) at org.jboss.kernel.plugins.dispatch.InvokeDispatchHelper.invoke(InvokeDispatchHelper.java:104) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.doUninstalls(InstallsAwareAction.java:214) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.doUninstalls(InstallsAwareAction.java:170) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.uninstallAction(InstallsAwareAction.java:156) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.uninstallAction(InstallsAwareAction.java:42) at org.jboss.dependency.plugins.action.SimpleControllerContextAction.simpleUninstallAction(SimpleControllerContextAction.java:79) at org.jboss.dependency.plugins.action.AccessControllerContextAction.uninstall(AccessControllerContextAction.java:131) at org.jboss.dependency.plugins.AbstractControllerContextActions.uninstall(AbstractControllerContextActions.java:58) at org.jboss.dependency.plugins.AbstractControllerContext.uninstall(AbstractControllerContext.java:354) at org.jboss.dependency.plugins.AbstractController.uninstall(AbstractController.java:1406) at org.jboss.dependency.plugins.AbstractController.uninstallContext(AbstractController.java:1064) at org.jboss.dependency.plugins.AbstractController.uninstallContext(AbstractController.java:986) at org.jboss.dependency.plugins.AbstractController.uninstall(AbstractController.java:513) at org.jboss.dependency.plugins.AbstractController.uninstall(AbstractController.java:470) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.undeployBean(AbstractKernelDeployer.java:406) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.undeployBeans(AbstractKernelDeployer.java:385) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.undeploy(AbstractKernelDeployer.java:162) at org.jboss.kernel.plugins.deployment.BasicKernelDeployer.undeploy(BasicKernelDeployer.java:88) at org.jboss.kernel.plugins.deployment.xml.BasicXMLDeployer.undeploy(BasicXMLDeployer.java:95) at org.jboss.kernel.plugins.deployment.BasicKernelDeployer.shutdown(BasicKernelDeployer.java:102) at org.jboss.bootstrap.microcontainer.ServerImpl.doShutdown(ServerImpl.java:165) at org.jboss.bootstrap.AbstractServerImpl.shutdownServer(AbstractServerImpl.java:523) at org.jboss.bootstrap.AbstractServerImpl$ShutdownHook.run(AbstractServerImpl.java:827) "main": at org.jboss.classloader.spi.base.BaseClassLoaderDomain.getClassLoaderSystem(BaseClassLoaderDomain.java:103) - waiting to lock <0xaef029b8> (a org.jboss.classloader.spi.ClassLoaderDomain) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.findLoader(BaseClassLoaderDomain.java:246) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.loadClass(BaseClassLoaderDomain.java:190) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.loadClass(BaseClassLoaderDomain.java:1009) at org.jboss.classloader.spi.base.BaseClassLoader.loadClassFromDomain(BaseClassLoader.java:728) at org.jboss.classloader.spi.base.BaseClassLoader.loadClass(BaseClassLoader.java:372) - locked <0xaef03488> (a org.jboss.classloader.spi.base.BaseClassLoader) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) - locked <0xaef03488> (a org.jboss.classloader.spi.base.BaseClassLoader) at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:620) at org.jboss.classloader.spi.base.BaseClassLoader.access$200(BaseClassLoader.java:63) at org.jboss.classloader.spi.base.BaseClassLoader$2.run(BaseClassLoader.java:502) at org.jboss.classloader.spi.base.BaseClassLoader$2.run(BaseClassLoader.java:462) at java.security.AccessController.doPrivileged(Native Method) at org.jboss.classloader.spi.base.BaseClassLoader.loadClassLocally(BaseClassLoader.java:460) - locked <0xaef03488> (a org.jboss.classloader.spi.base.BaseClassLoader) at org.jboss.classloader.spi.base.BaseClassLoader.loadClassLocally(BaseClassLoader.java:437) at org.jboss.classloader.spi.base.BaseDelegateLoader.loadClass(BaseDelegateLoader.java:134) at org.jboss.classloader.spi.filter.FilteredDelegateLoader.loadClass(FilteredDelegateLoader.java:131) at org.jboss.classloader.spi.base.ClassLoadingTask$ThreadTask.run(ClassLoadingTask.java:452) at org.jboss.classloader.spi.base.ClassLoaderManager.nextTask(ClassLoaderManager.java:254) at org.jboss.classloader.spi.base.ClassLoaderManager.process(ClassLoaderManager.java:148) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.loadClass(BaseClassLoaderDomain.java:196) at org.jboss.classloader.spi.base.BaseClassLoaderDomain.loadClass(BaseClassLoaderDomain.java:1009) at org.jboss.classloader.spi.base.BaseClassLoader.loadClassFromDomain(BaseClassLoader.java:728) at org.jboss.classloader.spi.base.BaseClassLoader.loadClass(BaseClassLoader.java:372) - locked <0xaef03488> (a org.jboss.classloader.spi.base.BaseClassLoader) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319) - locked <0xaef03488> (a org.jboss.classloader.spi.base.BaseClassLoader) at org.jboss.system.microcontainer.ServiceControllerContextActions.getLifecycleOnly(ServiceControllerContextActions.java:75) at org.jboss.system.microcontainer.ServiceControllerContext.<init>(ServiceControllerContext.java:88) at org.jboss.system.microcontainer.ServiceControllerContext.<init>(ServiceControllerContext.java:76) at org.jboss.system.ServiceController.postRegister(ServiceController.java:612) at org.jboss.mx.server.AbstractMBeanInvoker.invokePostRegister(AbstractMBeanInvoker.java:974) at org.jboss.mx.server.AbstractMBeanInvoker.postRegister(AbstractMBeanInvoker.java:681) at org.jboss.mx.server.registry.BasicMBeanRegistry.registerMBean(BasicMBeanRegistry.java:338) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:157) at org.jboss.mx.server.Invocation.dispatch(Invocation.java:96) at org.jboss.mx.interceptor.AbstractInterceptor.invoke(AbstractInterceptor.java:138) at org.jboss.mx.server.Invocation.invoke(Invocation.java:90) at org.jboss.mx.interceptor.ModelMBeanOperationInterceptor.invoke(ModelMBeanOperationInterceptor.java:140) at org.jboss.mx.server.Invocation.invoke(Invocation.java:90) at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:668) at org.jboss.mx.server.MBeanServerImpl$3.run(MBeanServerImpl.java:1431) at java.security.AccessController.doPrivileged(Native Method) at org.jboss.mx.server.MBeanServerImpl.registerMBean(MBeanServerImpl.java:1426) at org.jboss.mx.server.MBeanServerImpl.registerMBean(MBeanServerImpl.java:376) at org.jboss.system.server.jmx.JMXKernel.start(JMXKernel.java:191) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:585) at org.jboss.reflect.plugins.introspection.ReflectionUtils.invoke(ReflectionUtils.java:56) at org.jboss.reflect.plugins.introspection.ReflectMethodInfoImpl.invoke(ReflectMethodInfoImpl.java:110) at org.jboss.joinpoint.plugins.BasicMethodJoinPoint.dispatch(BasicMethodJoinPoint.java:66) at org.jboss.kernel.plugins.dependency.KernelControllerContextAction$JoinpointDispatchWrapper.execute(KernelControllerContextAction.java:241) at org.jboss.kernel.plugins.dependency.ExecutionWrapper.execute(ExecutionWrapper.java:45) at org.jboss.kernel.plugins.dependency.KernelControllerContextAction.dispatchExecutionWrapper(KernelControllerContextAction.java:109) at org.jboss.kernel.plugins.dependency.KernelControllerContextAction.dispatchJoinPoint(KernelControllerContextAction.java:70) at org.jboss.kernel.plugins.dependency.LifecycleAction.installActionInternal(LifecycleAction.java:221) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.installAction(InstallsAwareAction.java:54) at org.jboss.kernel.plugins.dependency.InstallsAwareAction.installAction(InstallsAwareAction.java:42) at org.jboss.dependency.plugins.action.SimpleControllerContextAction.simpleInstallAction(SimpleControllerContextAction.java:62) at org.jboss.dependency.plugins.action.AccessControllerContextAction.install(AccessControllerContextAction.java:71) at org.jboss.dependency.plugins.AbstractControllerContextActions.install(AbstractControllerContextActions.java:51) at org.jboss.dependency.plugins.AbstractControllerContext.install(AbstractControllerContext.java:348) at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:1392) at org.jboss.dependency.plugins.AbstractController.incrementState(AbstractController.java:784) at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:912) at org.jboss.dependency.plugins.AbstractController.resolveContexts(AbstractController.java:834) at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:624) at org.jboss.dependency.plugins.AbstractController.install(AbstractController.java:442) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.deployBean(AbstractKernelDeployer.java:331) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.deployBeans(AbstractKernelDeployer.java:309) at org.jboss.kernel.plugins.deployment.AbstractKernelDeployer.deploy(AbstractKernelDeployer.java:130) at org.jboss.kernel.plugins.deployment.BasicKernelDeployer.deploy(BasicKernelDeployer.java:76) at org.jboss.kernel.plugins.deployment.xml.BasicXMLDeployer.deploy(BasicXMLDeployer.java:88) at org.jboss.kernel.plugins.deployment.xml.BasicXMLDeployer.deploy(BasicXMLDeployer.java:158) at org.jboss.bootstrap.microcontainer.ServerImpl.doStart(ServerImpl.java:117) at org.jboss.bootstrap.AbstractServerImpl.start(AbstractServerImpl.java:398) at org.jboss.Main.boot(Main.java:209) at org.jboss.Main$1.run(Main.java:544) at java.lang.Thread.run(Thread.java:595) Found 1 deadlock. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: https://jira.jboss.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira