Another possibility to test: 1) Confirm behaviour is present on a NetBSD-10 kernel running on a NetBSD-9 install 2) Checkout trunk from the git mirror from around the netbsd-9 branch, build & test GENERIC kernel on netbsd-9 install 3) Checkout trunk from the git mirror from around the netbsd-10 branch, build & test GENERIC kernel on netbsd-9 install
Assuming the problem is absent in 2) and present in 3), 'git bisect good' and 'git bisect bad' them respectively then use git bisect to find out where the issue first occurred David
