cloud-init retry serial open

reopen.patch

diff --git a/cloudinit/sources/DataSourceSmartOS.py b/cloudinit/sources/DataSourceSmartOS.py
index 32655131..b1676f92 100644
--- a/cloudinit/sources/DataSourceSmartOS.py
+++ b/cloudinit/sources/DataSourceSmartOS.py
@@ -28,6 +29,7 @@ import os
 import random
 import re
 import socket
+import time
 
 from cloudinit import log as logging
 from cloudinit import serial
@@ -492,7 +494,23 @@ class JoyentMetadataSerialClient(JoyentMetadataClient):
     def open_transport(self):
         ser = serial.Serial(self.device, timeout=self.timeout)
         if not ser.isOpen():
-            raise SystemError("Unable to open %s" % self.device)
+            # There is some sort of a race between cloud-init and mdata-get
+            # that can cause the serial device to not open on the initial
+            # attempt.
+            for tries in range(1, 11):
+                try:
+                    ser.open()
+                    assert(ser.isOpen())
+                    break
+                except OSError as exc:
+                    # This is probably a SerialException, which is a subclass
+                    # of OSError.  SerialException is not used becasue of
+                    # existing efforts to make pyserial optional.
+                    LOG.debug("Failed to open %s on try %d: %s", self.device,
+                              tries, exc)
+                    time.sleep(0.1)
+            else:
+                raise SystemError("Unable to open %s" % self.device)
         fcntl.lockf(ser, fcntl.LOCK_EX)
         self.fp = ser