Add the beginnings of kernel debugging support. the kgdb(1) tool

is basicly a shell on top of libgdb that knows about kernel threads,
kernel modules and kvm(3). As the word "beginnings" implies, not
all of the features have been implemented yet. The tool is useful
and I'd like feedback on the taken route.

The simplest way to debug a kernel core file is:
	kgdb -n 0

This opens /var/crash/vmcore.0 with the corresponding kernel in
the object directory (kernel.debug is used if it exists).

Typical things that need to be added are:
o  Auto loading of kernel modules,
o  Handling of trapframes so that backtraces can be taken across
   them,
o  Some fancy commands to extract useful information out of a core
   file,
o  Various (probably many) other things.

1 files changed, 50 insertions, 0 deletions

diff --git a/gnu/usr.bin/gdb/kgdb/kgdb.1 b/gnu/usr.bin/gdb/kgdb/kgdb.1
new file mode 100644
index 0000000..2ade68b
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/kgdb.1
@@ -0,0 +1,50 @@
+.\" Copyright (c) 2004 Marcel Moolenaar
+.\" All rights reserved.
+.\"
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\"
+.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.
+.\"
+.\" $FreeBSD$
+.Dd August 1, 2004
+.Os
+.Dt KGDB 1
+.Sh NAME
+.Nm kgdb
+.Nd The kernel debugger
+.Sh SYNOPSIS
+.Nm
+.Op Ar -v
+.Op Ar -d crashdir
+.Op Ar -n dumpnr
+.Op Ar kernel [ Ar core ]
+.Sh DESCRIPTION
+The
+.Nm
+utility is a debugger based on
+.Xr gdb 1
+that allows debugging of kernel core files.
+.Sh SEE ALSO
+.Xr gdb 1
+.Sh HISTORY
+The
+.Nm
+utility first appeared in its current form in
+.Fx 5.3 .