qemu: ramfb video device doesn't support PCI address

Although a ramfb video device is not a PCI device, we don't currently
report an error for ramfb device definitions containing a PCI address.
However, a guest configured with such a device will fail to start:

    # virsh start test1
    error: Failed to start domain test1
    error: internal error: qemu unexpectedly closed the monitor: 2020-06-16T05:23:02.759221Z qemu-kvm: -device ramfb,id=video0,bus=pcie.0,addr=0x1: Device 'ramfb' can't go on PCIE bus

A better approach is to reject any device definitions that contain PCI
addresses.  While this is a change in behavior, any existing
configurations were non-functional.

https://bugzilla.redhat.com/show_bug.cgi?id=1847259Signed-off-by: NJonathon Jongsma <jjongsma@redhat.com>

src/qemu/qemu_validate.c

@@ -1925,6 +1925,14 @@ qemuValidateDomainDeviceDefVideo(const virDomainVideoDef *video,
     if (qemuValidateDomainVirtioOptions(video->virtio, qemuCaps) < 0)
         return -1;
 
+    if (video->type == VIR_DOMAIN_VIDEO_TYPE_RAMFB &&
+        video->info.type != VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("'address' is not supported for 'ramfb' video devices"));
+        return -1;
+    }
+
+
     return 0;
 }
 

tests/qemuxml2argvdata/video-ramfb-display-device-pci-address.xml

+<domain type='qemu'>
+  <name>QEMUGuest1</name>
+  <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid>
+  <memory unit='KiB'>1048576</memory>
+  <currentMemory unit='KiB'>1048576</currentMemory>
+  <vcpu>1</vcpu>
+  <os>
+    <type arch='i686' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/bin/qemu-system-i386</emulator>
+    <disk type='file' device='disk'>
+      <driver name='qemu' type='qcow2' cache='none'/>
+      <source file='/var/lib/libvirt/images/QEMUGuest1'/>
+      <target dev='hda' bus='ide'/>
+      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
+    </disk>
+    <controller type='ide' index='0'/>
+    <video>
+      <model type='ramfb' />
+      <address type='pci' domain='0x000' bus='0x00' slot='0x02' function='0x0'/>
+    </video>
+    <memballoon model='virtio'/>
+  </devices>
+</domain>

tests/qemuxml2argvtest.c

@@ -2276,6 +2276,7 @@ mymain(void)
             QEMU_CAPS_VIRTIO_GPU_MAX_OUTPUTS);
     DO_TEST_CAPS_LATEST("video-bochs-display-device");
     DO_TEST_CAPS_LATEST("video-ramfb-display-device");
+    DO_TEST_CAPS_LATEST_PARSE_ERROR("video-ramfb-display-device-pci-address");
     DO_TEST("video-none-device",
             QEMU_CAPS_VNC);
     DO_TEST_PARSE_ERROR("video-invalid-multiple-devices", NONE);