diff --git a/.zuul.yaml b/.zuul.yaml
index 3000c196b22..b3926585328 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -326,6 +326,10 @@
       devstack_services:
         openstack-cli-server: true
       devstack_local_conf:
+        post-config:
+          $NOVA_CPU_CONF:
+            libvirt:
+              images_address_space_limit: 2
         test-config:
           $TEMPEST_CONFIG:
             compute-feature-enabled:
@@ -787,6 +791,9 @@
               images_rbd_glance_store_name: robust
             workarounds:
               never_download_image_if_on_rbd: True
+          $NOVA_CPU_CONF:
+            libvirt:
+              images_address_space_limit: 2
           $GLANCE_API_CONF:
             DEFAULT:
               enabled_backends: "cheap:file, robust:rbd, web:http"
diff --git a/nova/cmd/baseproxy.py b/nova/cmd/baseproxy.py
index 9c8d298bce5..3f3604473e5 100644
--- a/nova/cmd/baseproxy.py
+++ b/nova/cmd/baseproxy.py
@@ -81,7 +81,7 @@ def proxy(host, port, security_proxy=None):
         ssl_minimum_version=CONF.console.ssl_minimum_version,
         daemon=CONF.daemon,
         record=CONF.record,
-        traffic=not CONF.daemon,
+        traffic=not CONF.daemon and CONF.debug,
         web=CONF.web,
         file_only=True,
         RequestHandlerClass=websocketproxy.NovaProxyRequestHandler,
diff --git a/nova/compute/api.py b/nova/compute/api.py
index ca6d9e58a64..6db75882369 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -2270,6 +2270,10 @@ def create(
                 msg = _('The requested availability zone is not available')
                 raise exception.InvalidRequest(msg)
 
+        if scheduler_hints:
+            scheduler_hints = {k: v for k, v in scheduler_hints.items()
+                               if not k.startswith('_nova')}
+
         filter_properties = scheduler_utils.build_filter_properties(
             scheduler_hints, forced_host, forced_node, flavor)
 
diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index ce6b98ddcd9..8c9614d334d 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -1151,10 +1151,14 @@ def _validate_vtpm_configuration(self, instances):
         if self.driver.capabilities.get('supports_vtpm', False):
             return
 
-        for instance in instances:
+        total_instances = len(instances)
+        for i, instance in enumerate(instances):
             if instance.deleted:
                 continue
 
+            LOG.debug('Checking vTPM constraint for instance %d/%d: %s',
+                      i + 1, total_instances, instance.uuid)
+
             # NOTE(stephenfin): We don't have an attribute on the instance to
             # check for this, so we need to inspect the flavor/image metadata
             if hardware.get_vtpm_constraint(
@@ -1781,10 +1785,13 @@ def init_host(self, service_ref):
         # startup before we start mucking with instances we think are
         # ours.
         self._check_for_host_rename(nodes_by_uuid)
-
+        expected_attrs = ['info_cache', 'metadata', 'system_metadata',
+                          'numa_topology', 'flavor']
+        LOG.debug('Loading instances for host %s with expected_attrs: %s',
+                  self.host, ', '.join(expected_attrs))
         instances = objects.InstanceList.get_by_host(
-            context, self.host,
-            expected_attrs=['info_cache', 'metadata', 'numa_topology'])
+            context, self.host, expected_attrs=expected_attrs)
+        LOG.debug('Loaded %d instances for host', len(instances))
 
         self.init_virt_events()
 
diff --git a/nova/conf/libvirt.py b/nova/conf/libvirt.py
index d65cdccbe5f..cadb19d9e21 100644
--- a/nova/conf/libvirt.py
+++ b/nova/conf/libvirt.py
@@ -1078,6 +1078,12 @@
 * Qemu >= 1.5 (raw format)
 * Qemu >= 1.6 (qcow2 format)
 """),
+    cfg.IntOpt('images_cpu_time_limit',
+               default=30,
+               help='CPU time process limit in seconds for qemu-img'),
+    cfg.IntOpt('images_address_space_limit',
+               default=1,
+               help='Address space process limit in gigabytes for qemu-img'),
 ]
 
 libvirt_lvm_opts = [
diff --git a/nova/console/websocketproxy.py b/nova/console/websocketproxy.py
index f71b9e1ebbe..c2b4e7f0494 100644
--- a/nova/console/websocketproxy.py
+++ b/nova/console/websocketproxy.py
@@ -203,7 +203,7 @@ def new_websocket_client(self):
                 expected_origin_hostname = e.split(']')[0][1:]
             else:
                 expected_origin_hostname = e.split(':')[0]
-        expected_origin_hostnames = CONF.console.allowed_origins
+        expected_origin_hostnames = list(CONF.console.allowed_origins)
         expected_origin_hostnames.append(expected_origin_hostname)
         origin_url = self.headers.get('Origin')
         # missing origin header indicates non-browser client which is OK
diff --git a/nova/privsep/qemu.py b/nova/privsep/qemu.py
index f1334b9dbb7..d70fc896f9f 100644
--- a/nova/privsep/qemu.py
+++ b/nova/privsep/qemu.py
@@ -25,15 +25,18 @@
 from oslo_log import log as logging
 from oslo_utils import units
 
+import nova.conf
 from nova import exception
 from nova.i18n import _
 import nova.privsep.utils
 
 LOG = logging.getLogger(__name__)
 
+CONF = nova.conf.CONF
+
 QEMU_IMG_LIMITS = processutils.ProcessLimits(
-    cpu_time=30,
-    address_space=1 * units.Gi)
+    cpu_time=CONF.libvirt.images_cpu_time_limit,
+    address_space=CONF.libvirt.images_address_space_limit * units.Gi)
 
 
 class EncryptionOptions(ty.TypedDict):
diff --git a/nova/tests/unit/cmd/test_baseproxy.py b/nova/tests/unit/cmd/test_baseproxy.py
index 25f3905f246..5d56413c849 100644
--- a/nova/tests/unit/cmd/test_baseproxy.py
+++ b/nova/tests/unit/cmd/test_baseproxy.py
@@ -71,7 +71,7 @@ def test_proxy(self, mock_select_ssl_version, mock_start, mock_init,
             listen_host='0.0.0.0', listen_port='6080', source_is_ipv6=False,
             cert='self.pem', key=None, ssl_only=False, ssl_ciphers=None,
             ssl_minimum_version='default', daemon=False, record=None,
-            security_proxy=None, traffic=True,
+            security_proxy=None, traffic=False,
             web='/usr/share/spice-html5', file_only=True,
             RequestHandlerClass=websocketproxy.NovaProxyRequestHandler)
         mock_start.assert_called_once_with()
@@ -98,6 +98,31 @@ def test_proxy_ssl_settings(self, mock_start, mock_init, mock_exists):
             listen_host='0.0.0.0', listen_port='6080', source_is_ipv6=False,
             cert='self.pem', key=None, ssl_only=False,
             ssl_ciphers='ALL:!aNULL', ssl_minimum_version='tlsv1_3',
-            daemon=False, record=None, security_proxy=None, traffic=True,
+            daemon=False, record=None, security_proxy=None, traffic=False,
             web='/usr/share/spice-html5', file_only=True,
             RequestHandlerClass=websocketproxy.NovaProxyRequestHandler)
+
+    @mock.patch('os.path.exists', return_value=True)
+    @mock.patch.object(logging, 'setup')
+    @mock.patch.object(gmr.TextGuruMeditation, 'setup_autorun')
+    @mock.patch('nova.console.websocketproxy.NovaWebSocketProxy.__init__',
+                return_value=None)
+    @mock.patch('nova.console.websocketproxy.NovaWebSocketProxy.start_server')
+    @mock.patch('websockify.websocketproxy.select_ssl_version',
+                return_value=None)
+    def test_proxy_with_traffic_logging(
+        self, mock_select_ssl_version, mock_start, mock_init, mock_gmr,
+        mock_log, mock_exists,
+    ):
+        self.flags(debug=True)
+        baseproxy.proxy('0.0.0.0', '6080')
+        mock_log.assert_called_once_with(baseproxy.CONF, 'nova')
+        mock_gmr.assert_called_once_with(version, conf=baseproxy.CONF)
+        mock_init.assert_called_once_with(
+            listen_host='0.0.0.0', listen_port='6080', source_is_ipv6=False,
+            cert='self.pem', key=None, ssl_only=False, ssl_ciphers=None,
+            ssl_minimum_version='default', daemon=False, record=None,
+            security_proxy=None, traffic=True,
+            web='/usr/share/spice-html5', file_only=True,
+            RequestHandlerClass=websocketproxy.NovaProxyRequestHandler)
+        mock_start.assert_called_once_with()
diff --git a/nova/tests/unit/compute/test_api.py b/nova/tests/unit/compute/test_api.py
index f68b5d774b2..4dd95f797b4 100644
--- a/nova/tests/unit/compute/test_api.py
+++ b/nova/tests/unit/compute/test_api.py
@@ -219,6 +219,24 @@ def _obj_to_list_obj(self, list_obj, obj):
         list_obj.obj_reset_changes()
         return list_obj
 
+    @mock.patch('nova.scheduler.utils.build_filter_properties')
+    def test_create_strips_internal_scheduler_hints(self,
+                                                    mock_build_filter):
+        mock_build_filter.side_effect = (
+            test.TestingException('stop early'))
+        flavor = self._create_flavor()
+        self.assertRaises(
+            test.TestingException,
+            self.compute_api.create,
+            self.context, flavor, 'image_id',
+            scheduler_hints={
+                '_nova_check_type': 'rebuild',
+                '_nova_future': 'something',
+                'group': 'valid-group-uuid',
+            })
+        actual_hints = mock_build_filter.call_args[0][0]
+        self.assertEqual({'group': 'valid-group-uuid'}, actual_hints)
+
     @mock.patch(
         'nova.network.neutron.API.is_remote_managed_port',
         new=mock.Mock(return_value=False),
diff --git a/nova/tests/unit/compute/test_compute_mgr.py b/nova/tests/unit/compute/test_compute_mgr.py
index 4b6980aff82..4772283b80a 100644
--- a/nova/tests/unit/compute/test_compute_mgr.py
+++ b/nova/tests/unit/compute/test_compute_mgr.py
@@ -1131,7 +1131,8 @@ def _do_mock_calls(mock_update_scheduler, mock_inst_init,
 
             mock_init_host.assert_called_once_with(host=our_host)
             mock_host_get.assert_called_once_with(self.context, our_host,
-                expected_attrs=['info_cache', 'metadata', 'numa_topology'])
+                expected_attrs=['info_cache', 'metadata', 'system_metadata',
+                                'numa_topology', 'flavor'])
 
             mock_update_scheduler.assert_called_once_with(
                 self.context, inst_list)
@@ -1307,7 +1308,8 @@ def test_init_host_with_evacuated_instance(self, mock_save, mock_mig_get,
 
         mock_init_host.assert_called_once_with(host=our_host)
         mock_host_get.assert_called_once_with(self.context, our_host,
-            expected_attrs=['info_cache', 'metadata', 'numa_topology'])
+            expected_attrs=['info_cache', 'metadata', 'system_metadata',
+                            'numa_topology', 'flavor'])
         mock_init_virt.assert_called_once_with()
         mock_temp_mut.assert_called_once_with(self.context, read_deleted='yes')
         mock_get_inst.assert_called_once_with(self.context)
diff --git a/nova/tests/unit/console/test_websocketproxy.py b/nova/tests/unit/console/test_websocketproxy.py
index 088ed8e64d2..8c3660bab24 100644
--- a/nova/tests/unit/console/test_websocketproxy.py
+++ b/nova/tests/unit/console/test_websocketproxy.py
@@ -658,6 +658,81 @@ def test_reject_open_redirect(self, url='//example.com/%2F..'):
     def test_reject_open_redirect_3_slashes(self):
         self.test_reject_open_redirect(url='///example.com/%2F..')
 
+    @mock.patch('nova.console.websocketproxy.NovaProxyRequestHandler.'
+                '_check_console_port')
+    @mock.patch('nova.objects.ConsoleAuthToken.validate')
+    def test_host_header_does_not_poison_allowed_origins(
+            self, validate, check_port):
+        """Verify that the Host header from one request does not persist in
+        CONF.console.allowed_origins and affect subsequent origin checks.
+
+        Regression test for bug 2158919.
+        """
+        params = {
+            'id': 1,
+            'token': '123-456-789',
+            'instance_uuid': uuids.instance,
+            'host': 'node1',
+            'port': '10000',
+            'console_type': 'novnc',
+            'access_url_base': 'https://example.net:6080'
+        }
+        validate.return_value = objects.ConsoleAuthToken(**params)
+
+        self.wh.socket.return_value = '<socket>'
+        self.wh.path = "http://127.0.0.1/?token=123-456-789"
+        self.wh.headers = self.fake_header
+
+        original_conf_origins = list(CONF.console.allowed_origins)
+
+        self.wh.new_websocket_client()
+
+        self.assertEqual(original_conf_origins,
+                         CONF.console.allowed_origins)
+
+    @mock.patch('nova.console.websocketproxy.NovaProxyRequestHandler.'
+                '_check_console_port')
+    @mock.patch('nova.objects.ConsoleAuthToken.validate')
+    def test_previous_host_does_not_bypass_origin_check(
+            self, validate, check_port):
+        """Verify that a Host header from a prior request cannot be used to
+        bypass the origin check on a subsequent request.
+
+        Regression test for bug 2158919.
+        """
+        params = {
+            'id': 1,
+            'token': '123-456-789',
+            'instance_uuid': uuids.instance,
+            'host': 'node1',
+            'port': '10000',
+            'console_type': 'novnc',
+            'access_url_base': 'https://example.net:6080'
+        }
+        validate.return_value = objects.ConsoleAuthToken(**params)
+
+        self.wh.socket.return_value = '<socket>'
+        self.wh.path = "http://127.0.0.1/?token=123-456-789"
+
+        # First request: Host header introduces evil.com
+        self.wh.headers = {
+            'cookie': 'token="123-456-789"',
+            'Origin': 'https://evil.com:6080',
+            'Host': 'evil.com:6080',
+        }
+        self.wh.new_websocket_client()
+
+        # Second request: Origin is evil.com but Host is legitimate.
+        # This must be rejected — evil.com should not have been persisted
+        # into the allow-list by the first request.
+        self.wh.headers = {
+            'cookie': 'token="123-456-789"',
+            'Origin': 'https://evil.com:6080',
+            'Host': 'example.net:6080',
+        }
+        self.assertRaises(exception.ValidationError,
+                          self.wh.new_websocket_client)
+
     @mock.patch('nova.objects.ConsoleAuthToken.validate')
     def test_no_compute_rpcapi_with_invalid_token(self, mock_validate):
         """Tests that we don't create a ComputeAPI object until we actually
diff --git a/nova/tests/unit/privsep/test_qemu.py b/nova/tests/unit/privsep/test_qemu.py
index e0554637e07..a1d720e8702 100644
--- a/nova/tests/unit/privsep/test_qemu.py
+++ b/nova/tests/unit/privsep/test_qemu.py
@@ -13,9 +13,11 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import importlib
 from unittest import mock
 
 import ddt
+from oslo_utils import units
 
 import nova.privsep.qemu
 from nova import test
@@ -203,9 +205,24 @@ def _test_qemu_img_info(self, method, mock_isdir, mock_execute):
         # Assert that the expected command is used
         mock_execute.assert_called_once_with(
             *expected_cmd, prlimit=nova.privsep.qemu.QEMU_IMG_LIMITS)
+        return mock_execute.call_args
 
     def test_privileged_qemu_img_info(self):
         self._test_qemu_img_info(nova.privsep.qemu.privileged_qemu_img_info)
 
     def test_unprivileged_qemu_img_info(self):
         self._test_qemu_img_info(nova.privsep.qemu.unprivileged_qemu_img_info)
+
+    def test_qemu_img_info_limits_config(self):
+        self.flags(images_cpu_time_limit=60, group='libvirt')
+        self.flags(images_address_space_limit=3, group='libvirt')
+        # Reload the nova.privsep.qemu module after setting the conf options
+        # because QEMU_IMG_LIMITS is global.
+        importlib.reload(nova.privsep.qemu)
+        # Save the call args of execute() to assert.
+        call_args = self._test_qemu_img_info(
+                nova.privsep.qemu.unprivileged_qemu_img_info)
+        # Verify that execute() was called with the configured values.
+        self.assertEqual(60, call_args.kwargs['prlimit'].cpu_time)
+        self.assertEqual(3 * units.Gi,
+                         call_args.kwargs['prlimit'].address_space)
diff --git a/releasenotes/notes/bug-2141981-5d5d3559c3b0a838.yaml b/releasenotes/notes/bug-2141981-5d5d3559c3b0a838.yaml
new file mode 100644
index 00000000000..0aa55fa99f2
--- /dev/null
+++ b/releasenotes/notes/bug-2141981-5d5d3559c3b0a838.yaml
@@ -0,0 +1,9 @@
+---
+fixes:
+  - |
+    Fixed slow nova-compute startup caused by lazy-loading instance
+    attributes. During init_host(), the _validate_vtpm_configuration()
+    method accesses instance.flavor and instance.image_meta, which
+    triggered 2*N sequential database queries for N instances. These
+    attributes are now pre-loaded in the initial InstanceList query,
+    reducing startup time significantly for hosts with many instances.
diff --git a/releasenotes/notes/console-token-origin-poison-f251ab9e3f63d6bd.yaml b/releasenotes/notes/console-token-origin-poison-f251ab9e3f63d6bd.yaml
new file mode 100644
index 00000000000..8f8c3df972f
--- /dev/null
+++ b/releasenotes/notes/console-token-origin-poison-f251ab9e3f63d6bd.yaml
@@ -0,0 +1,6 @@
+---
+security:
+  - |
+    Bug #2158919 is fixed, which involved an authenticated user able to poison
+    the server-side allowed origins list (and potentially exhaust memory by
+    extending it until failure).
diff --git a/releasenotes/notes/qemu-img-limits-config-dd49ea73c84a7cd4.yaml b/releasenotes/notes/qemu-img-limits-config-dd49ea73c84a7cd4.yaml
new file mode 100644
index 00000000000..22fa27c71ad
--- /dev/null
+++ b/releasenotes/notes/qemu-img-limits-config-dd49ea73c84a7cd4.yaml
@@ -0,0 +1,11 @@
+features:
+  - |
+    New configuration options ``[libvirt]images_cpu_time_limit`` and
+    ``[libvirt]images_address_space_limit`` have been added to enable tuning of
+    process limits for qemu-img. The default for
+    ``[libvirt]images_address_space_limit`` is unchanged from the hard-coded 1G
+    limit in order to maintain existing behavior. If you are using newer versions
+    of Ceph this should be increased. For more details, see bug `#2116852`_.
+
+    .. _#2116852: https://bugs.launchpad.net/nova/+bug/2116852
+