diff --git a/devicemodel/core/vmmapi.c b/devicemodel/core/vmmapi.c
index 16944fac7..3985ae01b 100644
--- a/devicemodel/core/vmmapi.c
+++ b/devicemodel/core/vmmapi.c
@@ -468,6 +468,7 @@ vm_map_gpa(struct vmctx *ctx, vm_paddr_t gaddr, size_t len)
 		}
 	}
 
+	pr_dbg("%s context memory is not valid!\n", __func__);
 	return NULL;
 }
 
diff --git a/devicemodel/hw/pci/virtio/virtio.c b/devicemodel/hw/pci/virtio/virtio.c
index 018b9c9e4..e176a0f87 100644
--- a/devicemodel/hw/pci/virtio/virtio.c
+++ b/devicemodel/hw/pci/virtio/virtio.c
@@ -342,18 +342,25 @@ virtio_vq_enable(struct virtio_base *base)
 	phys = (((uint64_t)vq->gpa_desc[1]) << 32) | vq->gpa_desc[0];
 	size = qsz * sizeof(struct vring_desc);
 	vb = paddr_guest2host(base->dev->vmctx, phys, size);
+	if (!vb)
+		goto error;
 	vq->desc = (struct vring_desc *)vb;
 
 	/* available ring */
 	phys = (((uint64_t)vq->gpa_avail[1]) << 32) | vq->gpa_avail[0];
 	size = (2 + qsz + 1) * sizeof(uint16_t);
 	vb = paddr_guest2host(base->dev->vmctx, phys, size);
+	if (!vb)
+		goto error;
+
 	vq->avail = (struct vring_avail *)vb;
 
 	/* used ring */
 	phys = (((uint64_t)vq->gpa_used[1]) << 32) | vq->gpa_used[0];
 	size = sizeof(uint16_t) * 3 + sizeof(struct vring_used_elem) * qsz;
 	vb = paddr_guest2host(base->dev->vmctx, phys, size);
+	if (!vb)
+		goto error;
 	vq->used = (struct vring_used *)vb;
 
 	/* Start at 0 when we use it. */
@@ -366,6 +373,9 @@ virtio_vq_enable(struct virtio_base *base)
 	/* Mark queue as allocated after initialization is complete. */
 	mb();
 	vq->flags = VQ_ALLOC;
+ error:
+	vq->flags = 0;
+	pr_err("%s: vq enable failed\n", __func__);
 }
 
 /*
diff --git a/devicemodel/hw/pci/virtio/virtio_console.c b/devicemodel/hw/pci/virtio/virtio_console.c
index c48a8307c..e44b3e955 100644
--- a/devicemodel/hw/pci/virtio/virtio_console.c
+++ b/devicemodel/hw/pci/virtio/virtio_console.c
@@ -412,7 +412,9 @@ virtio_console_notify_rx(void *vdev, struct virtio_vq_info *vq)
 
 	if (!port->rx_ready) {
 		port->rx_ready = 1;
-		vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+		if (vq_has_descs(vq)) {
+			vq->used->flags |= VRING_USED_F_NO_NOTIFY;
+		}
 	}
 }