[QPID-5117] Java client deadlocks if connection is closed while onMessage() is creating a session

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.22
• Fix Version/s: 0.31
• Component/s: JMS AMQP 0-x
• Assignee: Unassigned
• Reporter: Phil Harvey
• Created: 05/Sep/13 15:44
• Updated: 19/Mar/15 12:23
• Resolved: 10/Feb/15 09:47

Description

I have run the java systests with the JCarder agent attached. JCarder detected a potential deadlock when the following are done concurrently:

• Application thread closes a connection
• A MessageListener creates a new session on that connection inside onMessage().

Here is a sketch of the wrongly-ordered locking:

Thread "main"
	AMQConnection.close()
		AMQConnection.doClose()
			lock AMQConnection._sessionCreationLock
			lock AMQSession.getMessageDeliveryLock()

Thread "Dispatcher-1-Conn-780"
	AMQSession$Dispatcher.dispatchMessage()
		lock AMQSession.this._messageDeliveryLock
		myMessageListener.onMessage()
			AMQConnection.createSession()
				lock AMQConnection._sessionCreationLock

I've attached JCarder's GraphViz-format .dot file which represents this slightly more comprehensively.

Issue Links

• is part of: QPID-6374 [Java Client] Eliminate deadlocks by acquiring locks in a consistent order
• relates to: QPID-4574 [JMS] Deadlock involving _failoverMutex and _messageDeliveryLock