HEADSUP: KDB framework

Gang,

A new debugging framework has been committed. Besides adding support
for kernel threads to both DDB and remote GDB and other nice features,
there are some kernel configuration changes one needs to be aware of:

o  The DDB option is not to be used for conditional compilation of
   debugging related code or checks. The option is now controls the
   inclusion of the DDB debugger backend only. A new option, KDB,
   has been added for the conditional compilation of debugging code.
   Note that the KDB option does *not* affect the KDB frontend code.
   That code is non-conditional so that it can be used by modules
   without having to worry about it's presence.

o  The WITNESS_DDB, DDB_TRACE and DDB_UNATTENDED options have been
   renamed to WITNESS_KDB, KDB_TRACE and KDB_UNATTENDED as per the
   previous bullet. The options have no relation to the DDB backend.

o  There's no seperate option to use the symbols in the kernel image
   for symbol lookups instead of the kernel linker in DDB. Both are
   supported at the same time.

o  Support for remote GDB has been removed from DDB and added as a
   seperate debugger backend. Use option GDB to enable it.

o  The GDB debugger backend exports a simple interface to device so
   that they can register themselves as debug ports. Remote debugging
   is now possible using a more richer set of devices. The sio(4)
   driver has been converted, but the dcons(4) driver is a victim.
   Someone with the necessary firewire links needs to help out here.

There's probably more, but I've had enough for today :-)

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel_at_xcllnt.net