What does WARNING: [something] overlaps [something] in Windows Debugger mean?

I am editing the Windows Research Kernel (WRK) for part of a uni project, and occasionally when I start up the virtual machine running my kernel, the Windows Debugger says things like:

WARNING: rdpdr overlaps raspptp_baa74000
WARNING: ks overlaps rdpdr_baa26000
WARNING: ks overlaps raspptp_baa74000
WARNING: update_baa11000 overlaps ks_ba9fe000
WARNING: update_baa11000 overlaps rdpdr_baa26000
WARNING: tcpip overlaps tcpip_ba83e000

What does this actually mean?