virtio-serial: Cleanup on device hot-unplug

Free malloc'ed memory, unregister from savevm and clean up virtio-common
bits on device hot-unplug.

This was found performing a migration after device hot-unplug.

Reported-by: <lihuang@redhat.com>
Signed-off-by: NAmit Shah <amit.shah@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

hw/virtio-pci.c

@@ -599,6 +599,14 @@ static int virtio_serial_init_pci(PCIDevice *pci_dev)
     return 0;
 }
 
+static int virtio_serial_exit_pci(PCIDevice *pci_dev)
+{
+    VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
+
+    virtio_serial_exit(proxy->vdev);
+    return virtio_exit_pci(pci_dev);
+}
+
 static int virtio_net_init_pci(PCIDevice *pci_dev)
 {
     VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
@@ -689,7 +697,7 @@ static PCIDeviceInfo virtio_info[] = {
         .qdev.alias = "virtio-serial",
         .qdev.size = sizeof(VirtIOPCIProxy),
         .init      = virtio_serial_init_pci,
-        .exit      = virtio_exit_pci,
+        .exit      = virtio_serial_exit_pci,
         .qdev.props = (Property[]) {
             DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
                                DEV_NVECTORS_UNSPECIFIED),

hw/virtio-serial-bus.c

@@ -41,6 +41,8 @@ struct VirtIOSerial {
 
     VirtIOSerialBus *bus;
 
+    DeviceState *qdev;
+
     QTAILQ_HEAD(, VirtIOSerialPort) ports;
 
     /* bitmap for identifying active ports */
@@ -792,6 +794,8 @@ VirtIODevice *virtio_serial_init(DeviceState *dev, uint32_t max_nr_ports)
     vser->vdev.get_config = get_config;
     vser->vdev.set_config = set_config;
 
+    vser->qdev = dev;
+
     /*
      * Register for the savevm section with the virtio-console name
      * to preserve backward compat
@@ -801,3 +805,16 @@ VirtIODevice *virtio_serial_init(DeviceState *dev, uint32_t max_nr_ports)
 
     return vdev;
 }
+
+void virtio_serial_exit(VirtIODevice *vdev)
+{
+    VirtIOSerial *vser = DO_UPCAST(VirtIOSerial, vdev, vdev);
+
+    unregister_savevm(vser->qdev, "virtio-console", vser);
+
+    qemu_free(vser->ivqs);
+    qemu_free(vser->ovqs);
+    qemu_free(vser->ports_map);
+
+    virtio_cleanup(vdev);
+}

hw/virtio.h

@@ -195,6 +195,7 @@ VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf);
 
 void virtio_net_exit(VirtIODevice *vdev);
 void virtio_blk_exit(VirtIODevice *vdev);
+void virtio_serial_exit(VirtIODevice *vdev);
 
 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
 	DEFINE_PROP_BIT("indirect_desc", _state, _field, \