nova_hide_kvm.patch

diff --git a/nova/tests/unit/virt/libvirt/test_config.py b/nova/tests/unit/virt/libvirt/test_config.py
index 99382f5..04b056c 100644
--- a/nova/tests/unit/virt/libvirt/test_config.py
+++ b/nova/tests/unit/virt/libvirt/test_config.py
@@ -1845,6 +1845,7 @@ class LibvirtConfigGuestFeatureTest(LibvirtConfigBaseTest):
         obj.relaxed = True
         obj.vapic = True
         obj.spinlocks = True
+        obj.vendor_id = True
 
         xml = obj.to_xml()
         self.assertXmlEqual(xml, """
@@ -1852,8 +1853,20 @@ class LibvirtConfigGuestFeatureTest(LibvirtConfigBaseTest):
             <relaxed state="on"/>
             <vapic state="on"/>
             <spinlocks state="on" retries="4095"/>
+            <vendor_id state="on" value="MyFake_KVM"/>
           </hyperv>""")
 
+    def test_feature_kvm_hidden(self):
+
+        obj = config.LibvirtConfigGuestFeatureKVM()
+        obj.hidden = True
+
+        xml = obj.to_xml()
+        self.assertXmlEqual(xml, """
+          <kvm>
+            <hidden state="on"/>
+          </kvm>""")
+
 
 class LibvirtConfigGuestTest(LibvirtConfigBaseTest):
 
diff --git a/nova/tests/unit/virt/libvirt/test_driver.py b/nova/tests/unit/virt/libvirt/test_driver.py
index 9ac130c..61857e0 100644
--- a/nova/tests/unit/virt/libvirt/test_driver.py
+++ b/nova/tests/unit/virt/libvirt/test_driver.py
@@ -3159,6 +3159,53 @@ class LibvirtConnTestCase(test.NoDBTestCase):
         self.assertEqual(8191, cfg.features[2].spinlock_retries)
         self.assertTrue(cfg.features[2].vapic)
 
+    @mock.patch.object(host.Host, 'has_min_version')
+    def test_get_guest_config_windows_hide_kvm(self, mock_version):
+        mock_version.return_value = True
+        drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
+        instance_ref = objects.Instance(**self.test_instance)
+        instance_ref['os_type'] = 'windows'
+        instance_ref.flavor.extra_specs = {'hw:hide_kvm': 'True'}
+        image_meta = objects.ImageMeta.from_dict(self.test_image_meta)
+
+        disk_info = blockinfo.get_disk_info(CONF.libvirt.virt_type,
+                                            instance_ref,
+                                            image_meta)
+        cfg = drvr._get_guest_config(instance_ref,
+                                     _fake_network_info(self, 1),
+                                     image_meta, disk_info)
+
+        self.assertEqual(4, len(cfg.features))
+        self.assertIsInstance(cfg.features[2],
+                              vconfig.LibvirtConfigGuestFeatureHyperV)
+        self.assertIsInstance(cfg.features[3],
+                              vconfig.LibvirtConfigGuestFeatureKVM)
+
+        self.assertTrue(cfg.features[2].vendor_id)
+        self.assertEqual('MyFake_KVM', cfg.features[2].vendor_id_name)
+        self.assertTrue(cfg.features[3].hidden)
+
+    @mock.patch.object(host.Host, 'has_min_version')
+    def test_get_guest_config_non_windows_hide_kvm(self, mock_version):
+        mock_version.return_value = True
+        drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
+        instance_ref = objects.Instance(**self.test_instance)
+        instance_ref.flavor.extra_specs = {'hw:hide_kvm': 'True'}
+        image_meta = objects.ImageMeta.from_dict(self.test_image_meta)
+
+        disk_info = blockinfo.get_disk_info(CONF.libvirt.virt_type,
+                                            instance_ref,
+                                            image_meta)
+        cfg = drvr._get_guest_config(instance_ref,
+                                     _fake_network_info(self, 1),
+                                     image_meta, disk_info)
+
+        self.assertEqual(3, len(cfg.features))
+        self.assertIsInstance(cfg.features[2],
+                              vconfig.LibvirtConfigGuestFeatureKVM)
+
+        self.assertTrue(cfg.features[2].hidden)
+
     def test_get_guest_config_with_two_nics(self):
         drvr = libvirt_driver.LibvirtDriver(fake.FakeVirtAPI(), True)
         instance_ref = objects.Instance(**self.test_instance)
diff --git a/nova/virt/libvirt/config.py b/nova/virt/libvirt/config.py
index 1cf4d4f..ed98ee0 100644
--- a/nova/virt/libvirt/config.py
+++ b/nova/virt/libvirt/config.py
@@ -2004,6 +2004,7 @@ class LibvirtConfigGuestFeatureHyperV(LibvirtConfigGuestFeature):
 
     # QEMU requires at least this value to be set
     MIN_SPINLOCK_RETRIES = 4095
+    DEFAULT_VENDOR_ID = "MyFake_KVM"
 
     def __init__(self, **kwargs):
         super(LibvirtConfigGuestFeatureHyperV, self).__init__("hyperv",
@@ -2013,6 +2014,8 @@ class LibvirtConfigGuestFeatureHyperV(LibvirtConfigGuestFeature):
         self.vapic = False
         self.spinlocks = False
         self.spinlock_retries = self.MIN_SPINLOCK_RETRIES
+        self.vendor_id = False
+        self.vendor_id_name = self.DEFAULT_VENDOR_ID
 
     def format_dom(self):
         root = super(LibvirtConfigGuestFeatureHyperV, self).format_dom()
@@ -2024,6 +2027,26 @@ class LibvirtConfigGuestFeatureHyperV(LibvirtConfigGuestFeature):
         if self.spinlocks:
             root.append(etree.Element("spinlocks", state="on",
                                       retries=str(self.spinlock_retries)))
+        if self.vendor_id:
+            root.append(etree.Element("vendor_id", state="on",
+                                      value=self.vendor_id_name))
+
+        return root
+
+
+class LibvirtConfigGuestFeatureKVM(LibvirtConfigGuestFeature):
+
+    def __init__(self, **kwargs):
+        super(LibvirtConfigGuestFeatureKVM, self).__init__("kvm",
+                                                              **kwargs)
+
+        self.hidden = True
+
+    def format_dom(self):
+        root = super(LibvirtConfigGuestFeatureKVM, self).format_dom()
+
+        if self.hidden:
+            root.append(etree.Element("hidden", state="on"))
 
         return root
 
diff --git a/nova/virt/libvirt/driver.py b/nova/virt/libvirt/driver.py
index 3cc061d..e33bc3f 100644
--- a/nova/virt/libvirt/driver.py
+++ b/nova/virt/libvirt/driver.py
@@ -4177,7 +4177,7 @@ class LibvirtDriver(driver.ComputeDriver):
             tmhyperv.present = True
             clk.add_timer(tmhyperv)
 
-    def _set_features(self, guest, os_type, caps, virt_type):
+    def _set_features(self, guest, os_type, caps, virt_type, flavor):
         if virt_type == "xen":
             # PAE only makes sense in X86
             if caps.host.cpu.arch in (fields.Architecture.I686,
@@ -4189,6 +4189,11 @@ class LibvirtDriver(driver.ComputeDriver):
             guest.features.append(vconfig.LibvirtConfigGuestFeatureACPI())
             guest.features.append(vconfig.LibvirtConfigGuestFeatureAPIC())
 
+        # figure out if we are supposed to configure KVM so the
+        # guest is unaware running under it
+        hide_kvm = strutils.bool_from_string(
+            flavor.extra_specs.get('hw:hide_kvm', 'no'))
+
         if (virt_type in ("qemu", "kvm") and
                 os_type == 'windows'):
             hv = vconfig.LibvirtConfigGuestFeatureHyperV()
@@ -4200,8 +4205,16 @@ class LibvirtDriver(driver.ComputeDriver):
             # with Microsoft
             hv.spinlock_retries = 8191
             hv.vapic = True
+            if hide_kvm:
+                hv.vendor_id = True
             guest.features.append(hv)
 
+        if (virt_type in ("qemu", "kvm")) and hide_kvm:
+            kv = vconfig.LibvirtConfigGuestFeatureKVM()
+            kv.hidden = True # hide KVM from guest for NVidia GPU passthrough
+            guest.features.append(kv)
+
+
     def _check_number_of_serial_console(self, num_ports):
         virt_type = CONF.libvirt.virt_type
         if (virt_type in ("kvm", "qemu") and
@@ -4716,7 +4729,7 @@ class LibvirtDriver(driver.ComputeDriver):
             self._conf_non_lxc_uml(virt_type, guest, root_device_name, rescue,
                     instance, inst_path, image_meta, disk_info)
 
-        self._set_features(guest, instance.os_type, caps, virt_type)
+        self._set_features(guest, instance.os_type, caps, virt_type, flavor)
         self._set_clock(guest, instance.os_type, image_meta, virt_type)
 
         storage_configs = self._get_guest_storage_config(