[libvirt PATCH] qemu: ramfb video device doesn't support PCI address

[Jonathon Jongsma]

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=1847259

Signed-off-by: Jonathon Jongsma <jjongsma at redhat.com>
---
 src/conf/domain_conf.c   | 7 +++++++
 tests/qemuxml2argvtest.c | 1 +
 2 files changed, 8 insertions(+)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index fc7fcfb0c6..1a06cb3f4b 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -6608,6 +6608,13 @@ virDomainVideoDefValidate(const virDomainVideoDef *video,
         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;
+    }
+
     /* it doesn't make sense to pair video device type 'none' with any other
      * types, there can be only a single video device in such case
      */
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 1195f9c982..f2522fa530 100644
--- a/tests/qemuxml2argvtest.c
+++ b/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);
-- 
2.21.3