get_channel_info(hv_dev, device_info);
 
        if (!strcmp(dev_attr->attr.name, "class_id")) {
-               ret = sprintf(buf, "{%02x%02x%02x%02x-%02x%02x-%02x%02x-"
-                              "%02x%02x%02x%02x%02x%02x%02x%02x}\n",
-                              device_info->chn_type.b[3],
-                              device_info->chn_type.b[2],
-                              device_info->chn_type.b[1],
-                              device_info->chn_type.b[0],
-                              device_info->chn_type.b[5],
-                              device_info->chn_type.b[4],
-                              device_info->chn_type.b[7],
-                              device_info->chn_type.b[6],
-                              device_info->chn_type.b[8],
-                              device_info->chn_type.b[9],
-                              device_info->chn_type.b[10],
-                              device_info->chn_type.b[11],
-                              device_info->chn_type.b[12],
-                              device_info->chn_type.b[13],
-                              device_info->chn_type.b[14],
-                              device_info->chn_type.b[15]);
+               ret = sprintf(buf, "{%pUl}\n", device_info->chn_type.b);
        } else if (!strcmp(dev_attr->attr.name, "device_id")) {
-               ret = sprintf(buf, "{%02x%02x%02x%02x-%02x%02x-%02x%02x-"
-                              "%02x%02x%02x%02x%02x%02x%02x%02x}\n",
-                              device_info->chn_instance.b[3],
-                              device_info->chn_instance.b[2],
-                              device_info->chn_instance.b[1],
-                              device_info->chn_instance.b[0],
-                              device_info->chn_instance.b[5],
-                              device_info->chn_instance.b[4],
-                              device_info->chn_instance.b[7],
-                              device_info->chn_instance.b[6],
-                              device_info->chn_instance.b[8],
-                              device_info->chn_instance.b[9],
-                              device_info->chn_instance.b[10],
-                              device_info->chn_instance.b[11],
-                              device_info->chn_instance.b[12],
-                              device_info->chn_instance.b[13],
-                              device_info->chn_instance.b[14],
-                              device_info->chn_instance.b[15]);
+               ret = sprintf(buf, "{%pUl}\n", device_info->chn_instance.b);
        } else if (!strcmp(dev_attr->attr.name, "modalias")) {
                print_alias_name(hv_dev, alias_name);
                ret = sprintf(buf, "vmbus:%s\n", alias_name);