In your previous mail you wrote:

   has anybody got some experience using remote debugging with (k)gdb?
   
   I have built a kernel with 
   
   options KGDB                    # support for kernel gdb
   options KGDBDEV=0xc01, KGDBRATE=38400   # device & baud rate
   
   and I have connected 2 hosts with a serial line, but when I boot one with
   netbsd -d and run gdb on the other one and enter 'target remote /dev/ttyb'
   there is no connection established. Also, looking at the source for gdb
   and sparc/kgdb_* it seems to me, like they are talking 2 different
   protocols.
   
   Is it my fault or is KGDB not working on the sparc?
   
=> kgdb works only with the LBL gdb not the standard GNU gdb
(your hint is accurate, protocols are different). I had the same
problem with 4.4BSD...

Voila

Francis.Dupont@inria.fr

PS: here is the README.LBL of LBL gdb-4.7 I use :

Mon Apr 26 13:48:46 PDT 1993

This source tree contains kgdb, gdb-4.7 with kernel debugging
and control structure support from LBL (among many other changes
and bug fixes), developed by Van Jacobson, Steven McCanne,
Chris Torek, and  Craig Leres ({van,mccanne,torek,leres}@ee.lbl.gov).
This version of gdb also includes our X11 interface (type 'make xgdb'
in the gdb subdirectory after configuration -- it has only been tested
under R5).

This is an alpha release of the LBL contribution.  We are making
it available at this time so it can be included on the 4.4BSD tape.
We are in the progress of writing documention, which when complete,
will prompt the general release of kgdb.  Look for it via anonymous
ftp on ftp.ee.lbl.gov.

Please direct questions or problems to Steve McCanne (mccanne@ee.lbl.gov).