diff --git a/scripts/qemu.py b/scripts/qemu.py
index fd4249f7a8..768611f1de 100644
--- a/scripts/qemu.py
+++ b/scripts/qemu.py
@@ -148,11 +148,19 @@ class QEMUMachine(object):
         if opts:
             options.append(opts)
 
+        # This did not exist before 3.4, but since then it is
+        # mandatory for our purpose
+        if hasattr(os, 'set_inheritable'):
+            os.set_inheritable(fd, True)
+
         self._args.append('-add-fd')
         self._args.append(','.join(options))
         return self
 
-    def send_fd_scm(self, fd_file_path):
+    # Exactly one of fd and file_path must be given.
+    # (If it is file_path, the helper will open that file and pass its
+    # own fd)
+    def send_fd_scm(self, fd=None, file_path=None):
         # In iotest.py, the qmp should always use unix socket.
         assert self._qmp.is_scm_available()
         if self._socket_scm_helper is None:
@@ -160,12 +168,27 @@ class QEMUMachine(object):
         if not os.path.exists(self._socket_scm_helper):
             raise QEMUMachineError("%s does not exist" %
                                    self._socket_scm_helper)
+
+        # This did not exist before 3.4, but since then it is
+        # mandatory for our purpose
+        if hasattr(os, 'set_inheritable'):
+            os.set_inheritable(self._qmp.get_sock_fd(), True)
+            if fd is not None:
+                os.set_inheritable(fd, True)
+
         fd_param = ["%s" % self._socket_scm_helper,
-                    "%d" % self._qmp.get_sock_fd(),
-                    "%s" % fd_file_path]
+                    "%d" % self._qmp.get_sock_fd()]
+
+        if file_path is not None:
+            assert fd is None
+            fd_param.append(file_path)
+        else:
+            assert fd is not None
+            fd_param.append(str(fd))
+
         devnull = open(os.path.devnull, 'rb')
         proc = subprocess.Popen(fd_param, stdin=devnull, stdout=subprocess.PIPE,
-                                stderr=subprocess.STDOUT)
+                                stderr=subprocess.STDOUT, close_fds=False)
         output = proc.communicate()[0]
         if output:
             LOG.debug(output)
@@ -286,7 +309,8 @@ class QEMUMachine(object):
                                        stdin=devnull,
                                        stdout=self._qemu_log_file,
                                        stderr=subprocess.STDOUT,
-                                       shell=False)
+                                       shell=False,
+                                       close_fds=False)
         self._post_launch()
 
     def wait(self):
diff --git a/tests/qemu-iotests/045 b/tests/qemu-iotests/045
index 6be8fc4912..55a5d31ca8 100755
--- a/tests/qemu-iotests/045
+++ b/tests/qemu-iotests/045
@@ -140,7 +140,7 @@ class TestSCMFd(iotests.QMPTestCase):
         os.remove(image0)
 
     def _send_fd_by_SCM(self):
-        ret = self.vm.send_fd_scm(image0)
+        ret = self.vm.send_fd_scm(file_path=image0)
         self.assertEqual(ret, 0, 'Failed to send fd with UNIX SCM')
 
     def test_add_fd(self):
diff --git a/tests/qemu-iotests/147 b/tests/qemu-iotests/147
index d2081df84b..05b374b7d3 100755
--- a/tests/qemu-iotests/147
+++ b/tests/qemu-iotests/147
@@ -229,7 +229,7 @@ class BuiltinNBD(NBDBlockdevAddBase):
         sockfd = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
         sockfd.connect(unix_socket)
 
-        result = self.vm.send_fd_scm(str(sockfd.fileno()))
+        result = self.vm.send_fd_scm(fd=sockfd.fileno())
         self.assertEqual(result, 0, 'Failed to send socket FD')
 
         result = self.vm.qmp('getfd', fdname='nbd-fifo')