fix device hotplug

ChangeLog

+Thu Dec 18 17:46:06 CET 2008 Guido Günther <agx@sigxcpu.org>
+
+	* src/qemu_driver.c (qemudDomainAttachDevice): only
+	  free dev on failure
+
 Thu Dec 18 16:13:56 CET 2008 Guido Günther <agx@sigxcpu.org>
 
 	Let qemu/kvm instances write a pid file

src/qemu_driver.c

@@ -3222,7 +3222,8 @@ static int qemudDomainAttachDevice(virDomainPtr dom,
     }
 
 cleanup:
-    virDomainDeviceDefFree(dev);
+    if (ret < 0)
+        virDomainDeviceDefFree(dev);
     if (vm)
         virDomainObjUnlock(vm);
     return ret;