virtio-pci: Set the QEMU_PCI_CAP_EXPRESS capability early in its DeviceClass realize method

In 1811e64 'hw/virtio: Add PCIe capability to virtio devices', the
QEMU_PCI_CAP_EXPRESS capability was added to virtio's pci_dev, within
'virtio_pci_realize' - the pci device object realization method.

This occurs to late, as 'pci_qdev_realize' (DeviceClass.realize of
TYPE_PCI_DEVICE) has already been called, without knowing that the
device instance is indeed an "express" instance, thus allocating
insufficient pci config space.

As a result, device may crash upon attempt to write to the PCIE config
space.

Fix, by arming the QEMU_PCI_CAP_EXPRESS capability early in virtio-pci's
own DeviceClass realize method.

This also makes code cleaner, as 'virtio_pci_realize' may now access the
'pci_is_express' predicate when needed.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Tested-by: Marcel Apfelbaum <marcel@redhat.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index ffb74bb908..a104ff2072 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -105,6 +105,7 @@ typedef struct {
 
 typedef struct VirtioPCIClass {
     PCIDeviceClass parent_class;
+    DeviceRealize parent_dc_realize;
     void (*realize)(VirtIOPCIProxy *vpci_dev, Error **errp);
 } VirtioPCIClass;