--- old/test/java/rmi/testlibrary/RMID.java	2016-10-03 15:48:37.953635450 +0100
+++ new/test/java/rmi/testlibrary/RMID.java	2016-10-03 15:48:37.793638846 +0100
@@ -22,6 +22,17 @@
  */
 
 import java.io.*;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.ProtocolFamily;
+import java.net.ServerSocket;
+import java.nio.channels.Channel;
+import java.nio.channels.DatagramChannel;
+import java.nio.channels.Pipe;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.nio.channels.spi.AbstractSelector;
+import java.nio.channels.spi.SelectorProvider;
 import java.rmi.*;
 import java.rmi.activation.*;
 import java.rmi.registry.*;
@@ -49,8 +60,14 @@
 
     public static String MANAGER_OPTION="-Djava.security.manager=";
 
-    /** Test port for rmid */
-    private final int port;
+    /**
+     * Test port for rmid.
+     *
+     * May initially be 0, which means that the child rmid process will choose
+     * an ephemeral port and report it back to the parent process. This field
+     * will then be set to the child rmid's ephemeral port value.
+     */
+    private volatile int port;
 
     /** Initial log name */
     protected static String log = "log";
@@ -62,7 +79,7 @@
     }
 
     /** make test options and arguments */
-    private static String makeOptions(boolean debugExec) {
+    private static String makeOptions(int port, boolean debugExec) {
 
         String options = " -Dsun.rmi.server.activation.debugExec=" +
             debugExec;
@@ -87,6 +104,18 @@
         // to avoid spurious timeouts on slow machines.
         options += " -Dsun.rmi.activation.execTimeout=60000";
 
+        // Disable redirection of System.err to /tmp, even when using the
+        // inheritChannel mechanism.
+        options += " -Dsun.rmi.server.activation.disableErrRedirect";
+
+        if (port == 0) {
+            // Ephemeral port, so have the rmid child process create the
+            // server socket channel and report its port number, over stdin.
+            options += " -classpath " + TestParams.testClassPath;
+            options += " --add-exports=java.base/sun.nio.ch=ALL-UNNAMED";
+            options += " -Djava.nio.channels.spi.SelectorProvider=RMID$RMIDSelectorProvider";
+        }
+
         return options;
     }
 
@@ -107,7 +136,8 @@
         String args =
             " -log " + (new File(LOGDIR, log)).getAbsolutePath();
 
-        if (includePortArg) {
+        // 0 = ephemeral port, do no include an explicit port number
+        if (includePortArg && port != 0) {
             args += " -port " + port;
         }
 
@@ -160,7 +190,7 @@
                                   boolean debugExec, boolean includePortArg,
                                   int port)
     {
-        String options = makeOptions(debugExec);
+        String options = makeOptions(port, debugExec);
         String args = makeArgs(includePortArg, port);
         RMID rmid = new RMID("sun.rmi.server.Activation", options, args,
                              out, err, port);
@@ -169,6 +199,17 @@
         return rmid;
     }
 
+    public static RMID createRMIDOnEphemeralPort() {
+        return createRMID(System.out, System.err, true, true, 0);
+    }
+
+    public static RMID createRMIDOnEphemeralPort(OutputStream out,
+                                                 OutputStream err,
+                                                 boolean debugExec)
+    {
+        return createRMID(out, err, debugExec, true, 0);
+    }
+
 
     /**
      * Private constructor. RMID instances should be created
@@ -247,7 +288,10 @@
         // a well recognized exception (port already in use...).
 
         mesg("Starting rmid on port " + port + ".");
-        super.start();
+        int p = super.startAndGetPort();
+        if (p != -1)
+            port = p;
+        mesg("Started rmid on port " + port + ".");
 
         // int slopFactor = 1;
         // try {
@@ -271,8 +315,11 @@
 
             try {
                 int status = vm.exitValue();
+                waitFor(TIMEOUT_SHUTDOWN_MS);
                 TestLibrary.bomb("Rmid process exited with status " + status + " after " +
                     (System.currentTimeMillis() - startTime) + "ms.");
+            } catch (InterruptedException | TimeoutException e) {
+                mesg(e);
             } catch (IllegalThreadStateException ignore) { }
 
             // The rmid process is alive; check to see whether
@@ -307,6 +354,8 @@
      */
     public void restart() throws IOException {
         destroy();
+        options = makeOptions(port, true);
+        args = makeArgs(true, port);
         start();
     }
 
@@ -401,4 +450,68 @@
     public int getPort() {
         return port;
     }
+
+
+    /**
+     * A SelectorProvider, that can be loaded by the child rmid process, whose
+     * inheritedChannel method will create a new server socket channel and
+     * report it back to the parent process, over stdout.
+     */
+    public static class RMIDSelectorProvider extends SelectorProvider {
+
+        private final SelectorProvider provider;
+        private ServerSocketChannel channel;
+
+        public RMIDSelectorProvider() {
+            provider = sun.nio.ch.DefaultSelectorProvider.create();
+        }
+
+        public DatagramChannel openDatagramChannel()
+            throws IOException
+        {
+            return provider.openDatagramChannel();
+        }
+
+        public DatagramChannel openDatagramChannel(ProtocolFamily family)
+            throws IOException
+        {
+            return provider.openDatagramChannel(family);
+        }
+
+        public Pipe openPipe()
+            throws IOException
+        {
+            return provider.openPipe();
+        }
+
+        public AbstractSelector openSelector()
+                throws IOException
+        {
+            return provider.openSelector();
+        }
+
+        public ServerSocketChannel openServerSocketChannel()
+            throws IOException
+        {
+            return provider.openServerSocketChannel();
+        }
+
+        public SocketChannel openSocketChannel()
+            throws IOException
+        {
+            return provider.openSocketChannel();
+        }
+
+        public static final String MESSAGE = "RmidSelectorProvider-listening On:";
+
+        public synchronized Channel inheritedChannel() throws IOException {
+            System.out.println("RMIDSelectorProvider.inheritedChannel");
+            if (channel == null) {
+                // Create and bind a new server socket channel
+                channel = ServerSocketChannel.open().bind(new InetSocketAddress(0));
+                System.out.println(MESSAGE + channel.socket().getLocalPort());
+            }
+            return channel;
+        }
+    }
 }