diff -r d062d91d9dec -r e70261f11307 jdk/src/share/classes/sun/nio/ch/DatagramChannelImpl.java
--- a/jdk/src/share/classes/sun/nio/ch/DatagramChannelImpl.java	Wed Apr 17 02:53:02 2013 -0700
+++ b/jdk/src/share/classes/sun/nio/ch/DatagramChannelImpl.java	Wed Apr 17 16:11:19 2013 +0100
@@ -538,7 +538,7 @@
                     return 0;
                 readerThread = NativeThread.current();
                 do {
-                    n = IOUtil.read(fd, buf, -1, nd, readLock);
+                    n = IOUtil.read(fd, buf, -1, nd);
                 } while ((n == IOStatus.INTERRUPTED) && isOpen());
                 return IOStatus.normalize(n);
             } finally {
@@ -594,7 +594,7 @@
                     return 0;
                 writerThread = NativeThread.current();
                 do {
-                    n = IOUtil.write(fd, buf, -1, nd, writeLock);
+                    n = IOUtil.write(fd, buf, -1, nd);
                 } while ((n == IOStatus.INTERRUPTED) && isOpen());
                 return IOStatus.normalize(n);
             } finally {