Index: sys/dev/virtio/pci/virtio_pci.c
===================================================================
--- sys/dev/virtio/pci/virtio_pci.c
+++ sys/dev/virtio/pci/virtio_pci.c
@@ -288,8 +288,17 @@
 	sc->vtpci_res = bus_alloc_resource_any(dev, SYS_RES_IOPORT, &rid,
 	    RF_ACTIVE);
 	if (sc->vtpci_res == NULL) {
-		device_printf(dev, "cannot map I/O space\n");
-		return (ENXIO);
+		/*
+		 * We should try harder as the common configuration structure is
+		 * possible to be in memory space.
+		 */
+		rid = PCIR_BAR(0);
+		sc->vtpci_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
+		    RF_ACTIVE);
+		if (sc->vtpci_res == NULL) {
+			device_printf(dev, "cannot map I/O nor memory space\n");
+			return (ENXIO);
+		}
 	}
 
 	if (pci_find_cap(dev, PCIY_MSI, NULL) != 0)