Only issue with that is up time. Laptops have a tendency to go into sleep mode so if it does you lose DNS. Just gotta make sure it doesn't do that. I know some are incredibly annoying with power settings and you can't get rid of that behavior (Lenovo...).
Yo_2T
joined 1 year ago
Just disable dnsmasq or configure it to run on a different port.
This is old, but the diagrams in the first answer show you how to tag the ports to get the same setup as you described above:
https://superuser.com/questions/789294/can-i-send-a-wan-and-lan-connection-over-the-same-cable