For the last 3-5 days (since about the time of detachable devices ?),
current kernels on my Quadra 610 have been unusable. They die,
typically with 'Panic: MMU fault trap" during rc file processing.

I have seen it die in fsck, in usb, and to day in sh.

This kernel was made with a fresh config, then
make depend&&make clean&&make.

A ddb traceback from a few minutes ago says:

_Debugger
_panic
_trap
faultstackadj
_uvm_anfree(4e6a840) + 50
_amap_wipeout
_amap_unref
_uvm_unmap_detach
_uvm_unmap
_uvmspace_exec
_sys_execve
_syscall(3b)
_trap0

Further information can be provided on request.