virtio: do not reset msix state on soft reset

msix state is managed by OS, not the
driver, so it's wrong to touch it
on io from driver.
Mark all vectors unused instead.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

hw/virtio-pci.c

@@ -185,8 +185,10 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val)
         break;
     case VIRTIO_PCI_QUEUE_PFN:
         pa = (target_phys_addr_t)val << VIRTIO_PCI_QUEUE_ADDR_SHIFT;
-        if (pa == 0)
-            virtio_pci_reset(&proxy->pci_dev.qdev);
+        if (pa == 0) {
+            virtio_reset(proxy->vdev);
+            msix_unuse_all_vectors(&proxy->pci_dev);
+        }
         else
             virtio_queue_set_addr(vdev, vdev->queue_sel, pa);
         break;
@@ -199,8 +201,10 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val)
         break;
     case VIRTIO_PCI_STATUS:
         vdev->status = val & 0xFF;
-        if (vdev->status == 0)
-            virtio_pci_reset(&proxy->pci_dev.qdev);
+        if (vdev->status == 0) {
+            virtio_reset(proxy->vdev);
+            msix_unuse_all_vectors(&proxy->pci_dev);
+        }
         break;
     case VIRTIO_MSI_CONFIG_VECTOR:
         msix_vector_unuse(&proxy->pci_dev, vdev->config_vector);