From e1921703395cdc8807caa92813dcf1936d0ab64f Mon Sep 17 00:00:00 2001
From: John Griffith <john.griffith@solidfire.com>
Date: Thu, 7 Feb 2013 16:45:03 -0700
Subject: Fix missing key error in libvirt.driver

The libvirt disk mapping refactor change introduced
a bug in libvirt.driver.get_guest_config where we were
attempting to perform instance_update using a non-existent
key in the disk_mapping.

Given that we already parsed out the root_device_name and stored
it in a variable, and then verify that it's set in an if
statement before this method we should be just using what
we've already parsed.

Fixes bug: 1118829

Change-Id: Ifd80e67740d6f257ee537b68e9afe028273484d2
---
 nova/tests/test_libvirt.py  | 23 +++++++++++++++++++++++
 nova/virt/libvirt/driver.py |  2 +-
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index cef9252c5..e1a4ee294 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -433,6 +433,29 @@ class LibvirtConnTestCase(test.TestCase):
         self.assertEquals(type(cfg.devices[7]),
                           vconfig.LibvirtConfigGuestGraphics)
 
+    def test_get_guest_config_bug_1118829(self):
+        self.flags(libvirt_type='uml')
+        conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
+        instance_ref = db.instance_create(self.context, self.test_instance)
+
+        disk_info = {'disk_bus': 'virtio',
+                     'cdrom_bus': 'ide',
+                     'mapping': {u'vda': {'bus': 'virtio',
+                                          'type': 'disk',
+                                          'dev': u'vda'},
+                                 'root': {'bus': 'virtio',
+                                          'type': 'disk',
+                                          'dev': 'vda'}}}
+
+        # NOTE(jdg): For this specific test leave this blank
+        # This will exercise the failed code path still,
+        # and won't require fakes and stubs of the iscsi discovery
+        block_device_info = {}
+        cfg = conn.get_guest_config(instance_ref, [], None, disk_info,
+                                    None, block_device_info)
+        instance_ref = db.instance_get(self.context, instance_ref['id'])
+        self.assertEquals(instance_ref['root_device_name'], '/dev/vda')
+
     def test_get_guest_config_with_root_device_name(self):
         self.flags(libvirt_type='uml')
         conn = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 666eb66f3..9c6da127c 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -1789,7 +1789,7 @@ class LibvirtDriver(driver.ComputeDriver):
             # for nova.api.ec2.cloud.CloudController.get_metadata()
             self.virtapi.instance_update(
                 nova_context.get_admin_context(), instance['uuid'],
-                {'root_device_name': '/dev/' + disk_mapping['disk']['dev']})
+                {'root_device_name': root_device_name})
 
         guest.os_type = vm_mode.get_from_instance(instance)
 
-- 
cgit