Subject: remote kernel debugging - need some clarification
To: None <tech-kern@NetBSD.ORG, port-i386@NetBSD.ORG>
From: Matthias Drochner <drochner@zelux6.zel.kfa-juelich.de>
List: tech-kern
Date: 02/03/1997 22:37:52
It would be nice to have kgdb for the i386 too,
at least I'm a bit sick of finding the source of the
function calling points in machine-level DDB
stacktraces.
An example for i386 comes with gdb, and other ports
show how to integrate this. So far no problem.
I'm only confused about the variety of
implementations in the NetBSD tree and about the
meaning of some probably dead stubs in the i386
code.

My questions in particular:
1. A couple of ports (eg hp300, sun) use a protocol
  which is completely different from the original
  gdb one. Why? Are there historical reasons?
  Which debugger hangs on the other side?
2. ipkdb is again different - where does this protocol
  come from?
3. Why do these ports attach the debugger only at
  autoconfiguration time? Many interesting things can
  happen before... Or am I missing something?
4. Are there solutions for a reasonable coexistence
  of DDB and KGDB?
5. There are  #ifdef KGDB stubs in i386/locore.s,
  i386/machdep.c and isa/com.c. Has there been a
  kgdb implementation in former times, and do they
  serve any purpose now?

Any hints are welcome.

best regards
Matthias Drochner