testscript: Test that setting a function ID in a BDF fails

We need a negative test that shows, that adding a function ID when
entering a BDF result in libvirt generating a failure and CHV not
crashing.

Signed-off-by: Pascal Scholz <[email protected]>
On-behalf-of: SAP [email protected]

Author: scholzp

tests/common.nix

@@ -27,6 +27,8 @@ let
       serial ? "pty",
       # Whether all device will be assigned a static BDF through the XML or only some
       all_static_bdf ? false,
+      # Whether we add a function ID to specific BDFs or not
+      use_bdf_function ? false,
     }:
     ''
       <domain type='kvm' id='21050'>
@@ -136,9 +138,14 @@ let
             ${
               # Assign a fixed BDF that would normally be acquired by the implicit RNG device
               if all_static_bdf then
-                ''
-                  <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
-                ''
+                if use_bdf_function then
+                  ''
+                    <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+                  ''
+                else
+                  ''
+                    <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'/>
+                  ''
               else
                 ""
             }
@@ -569,6 +576,14 @@ in
             })}";
           };
         };
+        "/etc/domain-chv-static-bdf-with-function.xml" = {
+          "C+" = {
+            argument = "${pkgs.writeText "domain-chv-static-bdf-with-function.xml" (virsh_ch_xml {
+              all_static_bdf = true;
+              use_bdf_function = true;
+            })}";
+          };
+        };
         "/etc/new_interface.xml" = {
           "C+" = {
             argument = "${pkgs.writeText "new_interface.xml" (new_interface { })}";

tests/testscript.py

@@ -1850,13 +1850,50 @@ def test_bdf_invalid_device_id(self):
         )
         assert number_of_devices(controllerVM) == num_before_expected_failure
 
+    def test_bdf_valid_device_id_with_function_id(self):
+        """
+        Test that a BDFs containing a function ID leads to errors.
+
+        CHV currently doesn't support multi function devices. So we need
+        to checks that libvirt does not allow to attach such devices. We
+        check that instantiating a domain with function ID doesn't work.
+        Then we test that we cannot hotplug a device with a function ID
+        in its BDF definition.
+        """
+        # We don't support multi function devices currently. The config
+        # below defines a device with function ID, so instantiating it
+        # should fail.
+        controllerVM.fail("virsh define /etc/domain-chv-static-bdf-with-function.xml")
+
+        # Now create a VM from a definition that does not contain any
+        # function IDs in it device definition.
+        controllerVM.succeed("virsh define /etc/domain-chv.xml")
+        controllerVM.succeed("virsh start testvm")
+        assert wait_for_ssh(controllerVM)
+
+        # We need to check that no devices are added, so let's save how
+        # many devices are present in the VM after creating it.
+        num_before_expected_failure = number_of_devices(controllerVM)
+        # Now we create a disk that we hotplug to a BDF with a function
+        # ID. This should fail.
+        controllerVM.succeed(
+            "qemu-img create -f raw /var/lib/libvirt/storage-pools/nfs-share/vdb.img 5M"
+        )
+        controllerVM.fail(
+            "virsh attach-disk --domain testvm --target vdb --source /var/lib/libvirt/storage-pools/nfs-share/vdb.img --persistent --address pci:0.0.1f.5"
+        )
+        # Even though we only land here if the command above failed, we
+        # should still ensure that no new devices magically appeared.
+        assert number_of_devices(controllerVM) == num_before_expected_failure
+
 
 def suite():
     # Test cases in alphabetical order
     testcases = [
         LibvirtTests.test_bdf_explicit_assignment,
         LibvirtTests.test_bdf_implicit_assignment,
         LibvirtTests.test_bdf_invalid_device_id,
+        LibvirtTests.test_bdf_valid_device_id_with_function_id,
         LibvirtTests.test_bdfs_dont_conflict_after_transient_unplug,
         LibvirtTests.test_bdfs_implicitly_assgined_same_after_recreate,
         LibvirtTests.test_disk_is_locked,