
Add a 'serial' option to allow user to specify this value explicitly. And the default value is changed to an empty string as what we did in "hw/block/virtio-blk.c". Signed-off-by: Xie Yongji <xieyongji@bytedance.com> Message-Id: <20220614051532.92-6-xieyongji@bytedance.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>