The patch that satmandu mentioned in https://bugs.launchpad.net/ubuntu/+source/virtualbox/+bug/1830961/comments/16 fixes the v5.2.0 mainline kernel build as well.
The patch that satmandu mentioned in https:/ /bugs.launchpad .net/ubuntu/ +source/ virtualbox/ +bug/1830961/ comments/ 16 fixes the v5.2.0 mainline kernel build as well.