vmupdate: wait for full VM shutdown before next queued update

VMs with assigned PCI devices must be fully shut down before the next
update starts, because the hypervisor holds resources until shutdown
completes. Previously, qube_connection.py called vm.shutdown() and
moved on immediately, leaving PCI resources held.

Use shutdown_domains() from vmupdate.utils to issue a force shutdown
and wait for the domain to finish. Regular VMs (no PCI devices) are
unaffected and still use the fast non-blocking path.

Add unit tests covering:
- shutdown_domains is called and vm.shutdown is not for PCI VMs
- vm.shutdown is called and shutdown_domains is not for non-PCI VMs
- neither is called when the VM was already running before the update

Fixes: QubesOS/qubes-issues#10617

Author: Jayant-kernel

vmupdate/tests/test_qube_connection.py

@@ -0,0 +1,80 @@
+# coding=utf-8
+#
+# The Qubes OS Project, https://www.qubes-os.org
+#
+# Copyright (C) 2025  Jayant Saxena <jayantmcom@gmail.com>
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License
+# as published by the Free Software Foundation; either version 2
+# of the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+# USA.
+from unittest.mock import Mock, patch
+
+from vmupdate.qube_connection import QubeConnection
+
+
+@patch("vmupdate.qube_connection.shutdown_domains")
+def test_wait_for_shutdown_when_vm_started_by_update(shutdown_domains):
+    vm = Mock()
+    vm.name = "hvm1"
+    vm.is_running.side_effect = [False, True]
+    vm.devices = {'pci': Mock()}
+    vm.devices['pci'].get_assigned_devices.return_value = ["00_1f.2"]
+    status_notifier = Mock()
+    logger = Mock()
+
+    with QubeConnection(
+            vm, "/tmp/qubes-update", cleanup=False, logger=logger,
+            show_progress=False, status_notifier=status_notifier):
+        pass
+
+    shutdown_domains.assert_called_once_with([vm], logger)
+    vm.shutdown.assert_not_called()
+
+
+@patch("vmupdate.qube_connection.shutdown_domains")
+def test_do_not_wait_for_shutdown_without_assigned_pci(shutdown_domains):
+    vm = Mock()
+    vm.name = "hvm2"
+    vm.is_running.side_effect = [False, True]
+    vm.devices = {'pci': Mock()}
+    vm.devices['pci'].get_assigned_devices.return_value = []
+    status_notifier = Mock()
+    logger = Mock()
+
+    with QubeConnection(
+            vm, "/tmp/qubes-update", cleanup=False, logger=logger,
+            show_progress=False, status_notifier=status_notifier):
+        pass
+
+    vm.shutdown.assert_called_once_with()
+    shutdown_domains.assert_not_called()
+
+
+@patch("vmupdate.qube_connection.shutdown_domains")
+def test_do_not_shutdown_if_vm_was_already_running(shutdown_domains):
+    vm = Mock()
+    vm.name = "hvm3"
+    vm.is_running.return_value = True
+    vm.devices = {'pci': Mock()}
+    vm.devices['pci'].get_assigned_devices.return_value = ["00_1f.2"]
+    status_notifier = Mock()
+    logger = Mock()
+
+    with QubeConnection(
+            vm, "/tmp/qubes-update", cleanup=False, logger=logger,
+            show_progress=False, status_notifier=status_notifier):
+        pass
+
+    vm.shutdown.assert_not_called()
+    shutdown_domains.assert_not_called()