diff --git a/vendor/github.com/hashicorp/go-plugin/client.go b/vendor/github.com/hashicorp/go-plugin/client.go
index e559f713eee..3692736dae9 100644
--- a/vendor/github.com/hashicorp/go-plugin/client.go
+++ b/vendor/github.com/hashicorp/go-plugin/client.go
@@ -243,8 +243,16 @@ func (c *Client) Kill() {
 		return
 	}
 
-	// Kill the process
-	c.process.Kill()
+	// Close the client to cleanly exit the process
+	client, err := c.Client()
+	if err == nil {
+		err = client.Close()
+	}
+	if err != nil {
+		// If something went wrong somewhere gracefully quitting the
+		// plugin, we just force kill it.
+		c.process.Kill()
+	}
 
 	// Wait for the client to finish logging so we have a complete log
 	<-c.doneLogging
diff --git a/vendor/github.com/hashicorp/go-plugin/rpc_client.go b/vendor/github.com/hashicorp/go-plugin/rpc_client.go
index e6d613bc61d..29f9bf063e7 100644
--- a/vendor/github.com/hashicorp/go-plugin/rpc_client.go
+++ b/vendor/github.com/hashicorp/go-plugin/rpc_client.go
@@ -76,6 +76,13 @@ func (c *RPCClient) SyncStreams(stdout io.Writer, stderr io.Writer) error {
 // Close closes the connection. The client is no longer usable after this
 // is called.
 func (c *RPCClient) Close() error {
+	// Call the control channel and ask it to gracefully exit. If this
+	// errors, then we save it so that we always return an error but we
+	// want to try to close the other channels anyways.
+	var empty struct{}
+	returnErr := c.control.Call("Control.Quit", true, &empty)
+
+	// Close the other streams we have
 	if err := c.control.Close(); err != nil {
 		return err
 	}
@@ -85,8 +92,14 @@ func (c *RPCClient) Close() error {
 	if err := c.stderr.Close(); err != nil {
 		return err
 	}
+	if err := c.broker.Close(); err != nil {
+		return err
+	}
 
-	return c.broker.Close()
+	// Return back the error we got from Control.Quit. This is very important
+	// since we MUST return non-nil error if this fails so that Client.Kill
+	// will properly try a process.Kill.
+	return returnErr
 }
 
 func (c *RPCClient) Dispense(name string) (interface{}, error) {
diff --git a/vendor/github.com/hashicorp/go-plugin/rpc_server.go b/vendor/github.com/hashicorp/go-plugin/rpc_server.go
index 714b047dc5f..33601e207aa 100644
--- a/vendor/github.com/hashicorp/go-plugin/rpc_server.go
+++ b/vendor/github.com/hashicorp/go-plugin/rpc_server.go
@@ -22,6 +22,10 @@ type RPCServer struct {
 	// make our own custom one we pipe across.
 	Stdout io.Reader
 	Stderr io.Reader
+
+	// DoneCh should be set to a non-nil channel that will be closed
+	// when the control requests the RPC server to end.
+	DoneCh chan<- struct{}
 }
 
 // Accept accepts connections on a listener and serves requests for
@@ -84,6 +88,9 @@ func (s *RPCServer) ServeConn(conn io.ReadWriteCloser) {
 	// Use the control connection to build the dispenser and serve the
 	// connection.
 	server := rpc.NewServer()
+	server.RegisterName("Control", &controlServer{
+		server: s,
+	})
 	server.RegisterName("Dispenser", &dispenseServer{
 		broker:  broker,
 		plugins: s.Plugins,
@@ -91,6 +98,31 @@ func (s *RPCServer) ServeConn(conn io.ReadWriteCloser) {
 	server.ServeConn(control)
 }
 
+// done is called internally by the control server to trigger the
+// doneCh to close which is listened to by the main process to cleanly
+// exit.
+func (s *RPCServer) done() {
+	if s.DoneCh != nil {
+		close(s.DoneCh)
+	}
+}
+
+// dispenseServer dispenses variousinterface implementations for Terraform.
+type controlServer struct {
+	server *RPCServer
+}
+
+func (c *controlServer) Quit(
+	null bool, response *struct{}) error {
+	// End the server
+	c.server.done()
+
+	// Always return true
+	*response = struct{}{}
+
+	return nil
+}
+
 // dispenseServer dispenses variousinterface implementations for Terraform.
 type dispenseServer struct {
 	broker  *MuxBroker
diff --git a/vendor/github.com/hashicorp/go-plugin/server.go b/vendor/github.com/hashicorp/go-plugin/server.go
index 9d0de871f1e..b5c5270a7d8 100644
--- a/vendor/github.com/hashicorp/go-plugin/server.go
+++ b/vendor/github.com/hashicorp/go-plugin/server.go
@@ -98,11 +98,15 @@ func Serve(opts *ServeConfig) {
 	}
 	defer listener.Close()
 
+	// Create the channel to tell us when we're done
+	doneCh := make(chan struct{})
+
 	// Create the RPC server to dispense
 	server := &RPCServer{
 		Plugins: opts.Plugins,
 		Stdout:  stdout_r,
 		Stderr:  stderr_r,
+		DoneCh:  doneCh,
 	}
 
 	// Output the address and service name to stdout so that core can bring it up.
@@ -134,7 +138,10 @@ func Serve(opts *ServeConfig) {
 	os.Stderr = stderr_w
 
 	// Serve
-	server.Accept(listener)
+	go server.Accept(listener)
+
+	// Wait for the graceful exit
+	<-doneCh
 }
 
 func serverListener() (net.Listener, error) {
diff --git a/vendor/vendor.json b/vendor/vendor.json
index 5fdb65f305b..ab2c284b5da 100644
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@@ -461,10 +461,10 @@
 			"revision": "d30f09973e19c1dfcd120b2d9c4f168e68d6b5d5"
 		},
 		{
-			"checksumSHA1": "FK7oNTTXthoohAwDgVo/nmf1w9A=",
+			"checksumSHA1": "Jh6jdEjDeajnpEG8xlrLrnYw210=",
 			"path": "github.com/hashicorp/go-plugin",
-			"revision": "6691772c4e872547b2e6cfc54c853a6d61bc0edb",
-			"revisionTime": "2016-06-02T23:01:53Z"
+			"revision": "8cf118f7a2f0c7ef1c82f66d4f6ac77c7e27dc12",
+			"revisionTime": "2016-06-08T02:21:58Z"
 		},
 		{
 			"path": "github.com/hashicorp/go-syslog",