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.

11 files changed, 1089 insertions, 0 deletions

diff --git a/gnu/usr.bin/gdb/kgdb/Makefile b/gnu/usr.bin/gdb/kgdb/Makefile
new file mode 100644
index 0000000..561e22b
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/Makefile
@@ -0,0 +1,14 @@
+# $FreeBSD$
+
+PROG=	kgdb
+SRCS=	kthr.c main.c trgt.c trgt_${MACHINE_ARCH}.c
+WARNS?=	2
+
+BULIBS= ${OBJ_BU}/libbfd/libbfd.a ${OBJ_BU}/libopcodes/libopcodes.a \
+	${OBJ_BU}/libiberty/libiberty.a
+GDBLIBS= ${OBJ_GDB}/libgdb/libgdb.a
+
+DPADD=	${GDBLIBS} ${BULIBS} ${LIBKVM} ${LIBM} ${LIBREADLINE} ${LIBTERMCAP}
+LDADD=	${GDBLIBS} ${BULIBS} -lkvm -lm -lreadline -ltermcap
+
+.include <bsd.prog.mk>
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 .
diff --git a/gnu/usr.bin/gdb/kgdb/kgdb.h b/gnu/usr.bin/gdb/kgdb/kgdb.h
new file mode 100644
index 0000000..eb38032
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/kgdb.h
@@ -0,0 +1,55 @@
+/*
+ * 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.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _KGDB_H_
+#define	_KGDB_H_
+
+extern kvm_t *kvm;
+extern int verbose;
+
+struct kthr {
+	struct kthr	*next;
+	uintptr_t	kaddr;
+	uintptr_t	kstack;
+	uintptr_t	pcb;
+	int		tid;
+};
+
+extern struct kthr *curkthr;
+
+void kgdb_target(void);
+void kgdb_trgt_fetch_registers(int);
+void kgdb_trgt_store_registers(int);
+
+struct kthr *kgdb_thr_first(void);
+struct kthr *kgdb_thr_init(void);
+struct kthr *kgdb_thr_lookup(int);
+struct kthr *kgdb_thr_next(struct kthr *);
+struct kthr *kgdb_thr_select(struct kthr *);
+
+#endif /* _KGDB_H_ */
diff --git a/gnu/usr.bin/gdb/kgdb/kthr.c b/gnu/usr.bin/gdb/kgdb/kthr.c
new file mode 100644
index 0000000..25f8d49
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/kthr.c
@@ -0,0 +1,141 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/proc.h>
+#include <sys/types.h>
+#include <sys/signal.h>
+#include <err.h>
+#include <inttypes.h>
+#include <kvm.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "kgdb.h"
+
+static uintptr_t dumppcb;
+static int dumptid;
+
+static struct kthr *first;
+struct kthr *curkthr;
+
+static uintptr_t
+lookup(const char *sym)
+{
+	struct nlist nl[2];
+
+	nl[0].n_name = (char *)(uintptr_t)sym;
+	nl[1].n_name = NULL;
+	if (kvm_nlist(kvm, nl) != 0) {
+		warnx("kvm_nlist(%s): %s", sym, kvm_geterr(kvm));
+		return (0);
+	}
+	return (nl[0].n_value);
+}
+
+struct kthr *
+kgdb_thr_first(void)
+{
+	return (first);
+}
+
+struct kthr *
+kgdb_thr_init(void)
+{
+	struct proc p;
+	struct thread td;
+	struct kthr *kt;
+	uintptr_t addr, paddr;
+
+	addr = lookup("_allproc");
+	if (addr == 0)
+		return (NULL);
+	kvm_read(kvm, addr, &paddr, sizeof(paddr));
+
+	dumppcb = lookup("_dumppcb");
+	if (dumppcb == 0)
+		return (NULL);
+
+	addr = lookup("_dumptid");
+	if (addr != 0)
+		kvm_read(kvm, addr, &dumptid, sizeof(dumptid));
+	else
+		dumptid = -1;
+
+	while (paddr != 0) {
+		if (kvm_read(kvm, paddr, &p, sizeof(p)) != sizeof(p))
+			warnx("kvm_read: %s", kvm_geterr(kvm));
+		addr = (uintptr_t)TAILQ_FIRST(&p.p_threads);
+		while (addr != 0) {
+			if (kvm_read(kvm, addr, &td, sizeof(td)) != sizeof(td))
+				warnx("kvm_read: %s", kvm_geterr(kvm));
+			kt = malloc(sizeof(*kt));
+			kt->next = first;
+			kt->kaddr = addr;
+			kt->pcb = (td.td_tid == dumptid) ? dumppcb :
+			    (uintptr_t)td.td_pcb;
+			kt->kstack = td.td_kstack;
+			kt->tid = td.td_tid;
+			first = kt;
+			addr = (uintptr_t)TAILQ_NEXT(&td, td_plist);
+		}
+		paddr = (uintptr_t)LIST_NEXT(&p, p_list);
+	}
+	curkthr = kgdb_thr_lookup(dumptid);
+	if (curkthr == NULL)
+		curkthr = first;
+	return (first);
+}
+
+struct kthr *
+kgdb_thr_lookup(int tid)
+{
+	struct kthr *kt;
+
+	kt = first;
+	while (kt != NULL && kt->tid != tid)
+		kt = kt->next;
+	return (kt);
+}
+
+struct kthr *
+kgdb_thr_next(struct kthr *kt)
+{
+	return (kt->next);
+}
+
+struct kthr *
+kgdb_thr_select(struct kthr *kt)
+{
+	struct kthr *pcur;
+
+	pcur = curkthr;
+	curkthr = kt;
+	return (pcur);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/main.c b/gnu/usr.bin/gdb/kgdb/main.c
new file mode 100644
index 0000000..6204c0b
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/main.c
@@ -0,0 +1,288 @@
+/*
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <sys/resource.h>
+#include <sys/select.h>
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <errno.h>
+#include <err.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <kvm.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/* libgdb stuff. */
+#include <defs.h>
+#include <frame.h>
+#include <inferior.h>
+#include <interps.h>
+#include <cli-out.h>
+#include <main.h>
+#include <target.h>
+#include <top.h>
+
+extern void (*init_ui_hook)(char *);
+
+extern void symbol_file_add_main (char *args, int from_tty);
+
+#include "kgdb.h"
+
+kvm_t *kvm;
+
+static int dumpnr;
+static int verbose;
+
+static char crashdir[PATH_MAX];
+static char *kernel;
+static char *vmcore;
+
+static void (*kgdb_new_objfile_chain)(struct objfile * objfile);
+
+static void
+usage(void)
+{
+	fprintf(stderr,
+	    "usage: %s [-v] [-d crashdir] [-n dumpnr] [kernel [core]]\n",
+	    getprogname());
+	exit(1);
+}
+
+static void
+use_dump(int nr)
+{
+	char path[PATH_MAX];
+	FILE *info;
+	char *s;
+	struct stat st;
+	int l;
+
+	snprintf(path, sizeof(path), "%s/vmcore.%d", crashdir, nr);
+	if (stat(path, &st) == -1)
+		err(1, path);
+	if (!S_ISREG(st.st_mode))
+		errx(1, "%s: not a regular file", path);
+
+	vmcore = strdup(path);
+
+	/*
+	 * See if there's a kernel image right here, use it. The kernel
+	 * image is either called kernel.<nr> or is in a subdirectory
+	 * kernel.<nr> and called kernel.
+	 */
+	snprintf(path, sizeof(path), "%s/kernel.%d", crashdir, nr);
+	if (stat(path, &st) == 0) {
+		if (S_ISREG(st.st_mode)) {
+			kernel = strdup(path);
+			return;
+		}
+		if (S_ISDIR(st.st_mode)) {
+			snprintf(path, sizeof(path), "%s/kernel.%d/kernel",
+			    crashdir, nr);
+			if (stat(path, &st) == 0 && S_ISREG(st.st_mode)) {
+				kernel = strdup(path);
+				return;
+			}
+		}
+	}
+
+	/*
+	 * No kernel image here. Parse the dump header. The kernel object
+	 * directory can be found there and we probably have the kernel
+	 * image in it still.
+	 */
+	snprintf(path, sizeof(path), "%s/info.%d", crashdir, nr);
+	info = fopen(path, "r");
+	if (info == NULL) {
+		warn(path);
+		return;
+	}
+	while (fgets(path, sizeof(path), info) != NULL) {
+		l = strlen(path);
+		if (l > 0 && path[l - 1] == '\n')
+			path[--l] = '\0';
+		if (strncmp(path, "    ", 4) == 0) {
+			s = strchr(path, ':');
+			s = (s == NULL) ? path + 4 : s + 1;
+			l = snprintf(path, sizeof(path), "%s/kernel.debug", s);
+			if (stat(path, &st) == -1 || !S_ISREG(st.st_mode)) {
+				path[l - 6] = '\0';
+				if (stat(path, &st) == -1 ||
+				    !S_ISREG(st.st_mode))
+					break;
+			}
+			kernel = strdup(path);
+			break;
+		}
+	}
+	fclose(info);
+
+	if (verbose && kernel == NULL)
+		warnx("dump %d: no kernel found", nr);
+}
+
+static void
+kgdb_new_objfile(struct objfile *objfile)
+{
+#if 0
+	printf("XXX: %s(%p)\n", __func__, objfile);
+	if (objfile != NULL) {
+		goto out;
+	}
+
+out:
+#endif
+	if (kgdb_new_objfile_chain != NULL)
+		kgdb_new_objfile_chain(objfile);
+}
+
+static void
+kgdb_interp_command_loop(void *data)
+{
+	static int once = 0;
+
+	if (!once) {
+		symbol_file_add_main (kernel, 0);
+		print_stack_frame(get_current_frame(), -1, 0);
+		once = 1;
+	}
+	command_loop();
+}
+
+static void
+kgdb_init(char *argv0 __unused)
+{
+	static struct interp_procs procs = {
+		NULL,
+		NULL,
+		NULL,
+		NULL,
+		NULL,
+		kgdb_interp_command_loop
+	};
+	struct interp *kgdb;
+	kgdb = interp_new("kgdb", NULL, cli_out_new(gdb_stdout), &procs);
+	interp_add(kgdb);
+
+	set_prompt("(kgdb) ");
+	kgdb_target();
+	kgdb_new_objfile_chain = target_new_objfile_hook;
+	target_new_objfile_hook = kgdb_new_objfile;
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct captured_main_args args;
+	char *s;
+	int ch;
+
+	dumpnr = -1;
+
+	strlcpy(crashdir, "/var/crash", sizeof(crashdir));
+	s = getenv("KGDB_CRASH_DIR");
+	if (s != NULL)
+		strlcpy(crashdir, s, sizeof(crashdir));
+
+	while ((ch = getopt(argc, argv, "d:n:v")) != -1) {
+		switch (ch) {
+		case 'd':
+			strlcpy(crashdir, optarg, sizeof(crashdir));
+			break;
+		case 'n':
+			dumpnr = strtol(optarg, &s, 0);
+			if (dumpnr < 0 || *s != '\0') {
+				warnx("option %c: invalid kernel dump number",
+				    optopt);
+				usage();
+				/* NOTREACHED */
+			}
+			break;
+		case 'v':
+			verbose++;
+			break;
+		case '?':
+		default:
+			usage();
+		}
+	}
+
+	if (verbose > 1)
+		warnx("using %s as the crash directory", crashdir);
+
+	if (dumpnr >= 0)
+		use_dump(dumpnr);
+
+	if (argc > optind) {
+		if (kernel != NULL)
+			free(kernel);
+		kernel = strdup(argv[optind++]);
+	}
+	while (argc > optind) {
+		if (vmcore != NULL)
+			errx(1, "multiple core files specified");
+		vmcore = strdup(argv[optind++]);
+	}
+
+	if (kernel == NULL)
+		errx(1, "kernel not specified");
+	if (vmcore == NULL)
+		errx(1, "core file not specified");
+
+	if (verbose) {
+		warnx("kernel image: %s", kernel);
+		warnx("core file: %s", vmcore);
+	}
+
+	s = malloc(_POSIX2_LINE_MAX);
+	kvm = kvm_openfiles(kernel, vmcore, NULL, O_RDONLY, s);
+	if (kvm == NULL)
+		errx(1, s);
+	free(s);
+
+	kgdb_thr_init();
+
+	memset (&args, 0, sizeof args);
+	args.argc = 1;
+	args.argv = argv;
+	args.use_windows = 0;
+	args.interpreter_p = "kgdb";
+
+	init_ui_hook = kgdb_init;
+
+	return (gdb_main(&args));
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt.c b/gnu/usr.bin/gdb/kgdb/trgt.c
new file mode 100644
index 0000000..5c889eb
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt.c
@@ -0,0 +1,112 @@
+/*
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <kvm.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <target.h>
+
+static struct target_ops kgdb_trgt_ops;
+
+static char *
+kgdb_trgt_extra_thread_info(struct thread_info *ti __unused)
+{
+	return (NULL);
+}
+
+static void
+kgdb_trgt_find_new_threads(void)
+{
+}
+
+static char *
+kgdb_trgt_pid_to_str(ptid_t ptid)
+{
+	static char buf[16];
+
+	snprintf(buf, sizeof(buf), "TID %d", ptid_get_pid(ptid));
+	return (buf);
+}
+
+static int
+kgdb_trgt_thread_alive(ptid_t ptid)
+{
+	return (kgdb_thr_lookup(ptid_get_pid(ptid)) != NULL);
+}
+
+static int
+kgdb_trgt_xfer_memory(CORE_ADDR memaddr, char *myaddr, int len, int write,
+    struct mem_attrib *attrib __unused, struct target_ops *target __unused)
+{
+	if (len == 0)
+		return (0);
+
+	if (!write)
+		return (kvm_read(kvm, memaddr, myaddr, len));
+	else
+		return (kvm_write(kvm, memaddr, myaddr, len));
+}
+
+void
+kgdb_target(void)
+{
+	struct kthr *kt;
+	struct thread_info *ti;
+
+	kgdb_trgt_ops.to_magic = OPS_MAGIC;
+	kgdb_trgt_ops.to_shortname = "kernel";
+	kgdb_trgt_ops.to_longname = "kernel core files.";
+	kgdb_trgt_ops.to_doc = "Kernel core files.";
+	kgdb_trgt_ops.to_stratum = thread_stratum;
+	kgdb_trgt_ops.to_has_memory = 1;
+	kgdb_trgt_ops.to_has_registers = 1;
+	kgdb_trgt_ops.to_has_stack = 1;
+
+	kgdb_trgt_ops.to_extra_thread_info = kgdb_trgt_extra_thread_info;
+	kgdb_trgt_ops.to_fetch_registers = kgdb_trgt_fetch_registers;
+	kgdb_trgt_ops.to_find_new_threads = kgdb_trgt_find_new_threads;
+	kgdb_trgt_ops.to_pid_to_str = kgdb_trgt_pid_to_str;
+	kgdb_trgt_ops.to_store_registers = kgdb_trgt_store_registers;
+	kgdb_trgt_ops.to_thread_alive = kgdb_trgt_thread_alive;
+	kgdb_trgt_ops.to_xfer_memory = kgdb_trgt_xfer_memory;
+	add_target(&kgdb_trgt_ops);
+	push_target(&kgdb_trgt_ops);
+
+	kt = kgdb_thr_first();
+	while (kt != NULL) {
+		ti = add_thread(ptid_build(kt->tid, 0, 0));
+		kt = kgdb_thr_next(kt);
+	}
+	inferior_ptid = ptid_build(curkthr->tid, 0, 0);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_alpha.c b/gnu/usr.bin/gdb/kgdb/trgt_alpha.c
new file mode 100644
index 0000000..891b0eb
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_alpha.c
@@ -0,0 +1,73 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/pcb.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;
+
+	kt = kgdb_thr_lookup(ptid_get_pid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+
+	supply_register(9, (char *)&pcb.pcb_context[0]);
+	supply_register(10, (char *)&pcb.pcb_context[1]);
+	supply_register(11, (char *)&pcb.pcb_context[2]);
+	supply_register(12, (char *)&pcb.pcb_context[3]);
+	supply_register(13, (char *)&pcb.pcb_context[4]);
+	supply_register(14, (char *)&pcb.pcb_context[5]);
+	supply_register(15, (char *)&pcb.pcb_context[6]);
+	supply_register(30, (char *)&pcb.pcb_hw.apcb_ksp);
+	supply_register(64, (char *)&pcb.pcb_context[7]);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_amd64.c b/gnu/usr.bin/gdb/kgdb/trgt_amd64.c
new file mode 100644
index 0000000..e193969
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_amd64.c
@@ -0,0 +1,73 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/pcb.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;
+
+	kt = kgdb_thr_lookup(ptid_get_pid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+
+	supply_register(1, (char *)&pcb.pcb_rbx);
+	supply_register(6, (char *)&pcb.pcb_rbp);
+	supply_register(7, (char *)&pcb.pcb_rsp);
+	supply_register(12, (char *)&pcb.pcb_r12);
+	supply_register(13, (char *)&pcb.pcb_r13);
+	supply_register(14, (char *)&pcb.pcb_r14);
+	supply_register(15, (char *)&pcb.pcb_r15);
+	supply_register(16, (char *)&pcb.pcb_rip);
+	supply_register(17, (char *)&pcb.pcb_rflags);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_i386.c b/gnu/usr.bin/gdb/kgdb/trgt_i386.c
new file mode 100644
index 0000000..36c1ed0
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_i386.c
@@ -0,0 +1,69 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/pcb.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;
+
+	kt = kgdb_thr_lookup(ptid_get_pid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+	supply_register(3, (char *)&pcb.pcb_ebx);
+	supply_register(4, (char *)&pcb.pcb_esp);
+	supply_register(5, (char *)&pcb.pcb_ebp);
+	supply_register(6, (char *)&pcb.pcb_esi);
+	supply_register(7, (char *)&pcb.pcb_edi);
+	supply_register(8, (char *)&pcb.pcb_eip);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_ia64.c b/gnu/usr.bin/gdb/kgdb/trgt_ia64.c
new file mode 100644
index 0000000..15609af
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_ia64.c
@@ -0,0 +1,133 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/md_var.h>
+#include <machine/pcb.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;
+	uint64_t r;
+
+	kt = kgdb_thr_lookup(ptid_get_pid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+
+	/* Registers 0-127: general registers. */
+	supply_register(1, (char *)&pcb.pcb_special.gp);
+	supply_register(4, (char *)&pcb.pcb_preserved.gr4);
+	supply_register(5, (char *)&pcb.pcb_preserved.gr5);
+	supply_register(6, (char *)&pcb.pcb_preserved.gr6);
+	supply_register(7, (char *)&pcb.pcb_preserved.gr7);
+	supply_register(12, (char *)&pcb.pcb_special.sp);
+	supply_register(13, (char *)&pcb.pcb_special.tp);
+
+	/* Registers 128-255: floating-point registers. */
+	supply_register(130, (char *)&pcb.pcb_preserved_fp.fr2);
+	supply_register(131, (char *)&pcb.pcb_preserved_fp.fr3);
+	supply_register(132, (char *)&pcb.pcb_preserved_fp.fr4);
+	supply_register(133, (char *)&pcb.pcb_preserved_fp.fr5);
+	supply_register(144, (char *)&pcb.pcb_preserved_fp.fr16);
+	supply_register(145, (char *)&pcb.pcb_preserved_fp.fr17);
+	supply_register(146, (char *)&pcb.pcb_preserved_fp.fr18);
+	supply_register(147, (char *)&pcb.pcb_preserved_fp.fr19);
+	supply_register(148, (char *)&pcb.pcb_preserved_fp.fr20);
+	supply_register(149, (char *)&pcb.pcb_preserved_fp.fr21);
+	supply_register(150, (char *)&pcb.pcb_preserved_fp.fr22);
+	supply_register(151, (char *)&pcb.pcb_preserved_fp.fr23);
+	supply_register(152, (char *)&pcb.pcb_preserved_fp.fr24);
+	supply_register(153, (char *)&pcb.pcb_preserved_fp.fr25);
+	supply_register(154, (char *)&pcb.pcb_preserved_fp.fr26);
+	supply_register(155, (char *)&pcb.pcb_preserved_fp.fr27);
+	supply_register(156, (char *)&pcb.pcb_preserved_fp.fr28);
+	supply_register(157, (char *)&pcb.pcb_preserved_fp.fr29);
+	supply_register(158, (char *)&pcb.pcb_preserved_fp.fr30);
+	supply_register(159, (char *)&pcb.pcb_preserved_fp.fr31);
+
+	/* Registers 320-327: branch registers. */
+	if (pcb.pcb_special.__spare == ~0UL)
+		supply_register(320, (char *)&pcb.pcb_special.rp);
+	supply_register(321, (char *)&pcb.pcb_preserved.br1);
+	supply_register(322, (char *)&pcb.pcb_preserved.br2);
+	supply_register(323, (char *)&pcb.pcb_preserved.br3);
+	supply_register(324, (char *)&pcb.pcb_preserved.br4);
+	supply_register(325, (char *)&pcb.pcb_preserved.br5);
+
+	/* Registers 328-333: misc. other registers. */
+	supply_register(330, (char *)&pcb.pcb_special.pr);
+	if (pcb.pcb_special.__spare == ~0UL) {
+		r = pcb.pcb_special.iip + ((pcb.pcb_special.psr >> 41) & 3);
+		supply_register(331, (char *)&r);
+		supply_register(333, (char *)&pcb.pcb_special.cfm);
+	} else {
+		supply_register(331, (char *)&pcb.pcb_special.rp);
+		supply_register(333, (char *)&pcb.pcb_special.pfs);
+	}
+
+	/* Registers 334-461: application registers. */
+	supply_register(350, (char *)&pcb.pcb_special.rsc);
+	r = pcb.pcb_special.bspstore;
+	if (pcb.pcb_special.__spare == ~0UL)
+		r += pcb.pcb_special.ndirty;
+	else
+		r = ia64_bsp_adjust(r, IA64_CFM_SOF(pcb.pcb_special.pfs) -
+		    IA64_CFM_SOL(pcb.pcb_special.pfs));
+	supply_register(351, (char *)&r);	/* bsp */
+	supply_register(352, (char *)&r);	/* bspstore */
+	supply_register(353, (char *)&pcb.pcb_special.rnat);
+	supply_register(370, (char *)&pcb.pcb_special.unat);
+	supply_register(374, (char *)&pcb.pcb_special.fpsr);
+	if (pcb.pcb_special.__spare == ~0UL)
+		supply_register(398, (char *)&pcb.pcb_special.pfs);
+	supply_register(399, (char *)&pcb.pcb_preserved.lc);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}
diff --git a/gnu/usr.bin/gdb/kgdb/trgt_sparc64.c b/gnu/usr.bin/gdb/kgdb/trgt_sparc64.c
new file mode 100644
index 0000000..81f9a86
--- /dev/null
+++ b/gnu/usr.bin/gdb/kgdb/trgt_sparc64.c
@@ -0,0 +1,81 @@
+/*
+ * 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 AUTHORS ``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 AUTHORS 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/types.h>
+#include <machine/asm.h>
+#include <machine/pcb.h>
+#include <err.h>
+#include <kvm.h>
+#include <string.h>
+
+#include "kgdb.h"
+
+#include <defs.h>
+#include <target.h>
+#include <gdbthread.h>
+#include <inferior.h>
+#include <regcache.h>
+
+void
+kgdb_trgt_fetch_registers(int regno __unused)
+{
+	struct kthr *kt;
+	struct pcb pcb;
+	uint64_t r;
+
+	kt = kgdb_thr_lookup(ptid_get_pid(inferior_ptid));
+	if (kt == NULL)
+		return;
+	if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
+		warnx("kvm_read: %s", kvm_geterr(kvm));
+		memset(&pcb, 0, sizeof(pcb));
+	}
+
+	/* 0-7: global registers (g0-g7) */
+
+	/* 8-15: output registers (o0-o7) */
+	r = pcb.pcb_sp - CCFSZ;
+	supply_register(14, (char *)&r);
+
+	/* 16-23: local registers (l0-l7) */
+
+	/* 24-31: input registers (i0-i7) */
+	supply_register(30, (char *)&pcb.pcb_sp);
+
+	/* 32-63: single precision FP (f0-f31) */
+
+	/* 64-79: double precision FP (f32-f62) */
+	supply_register(80, (char *)&pcb.pcb_pc);
+}
+
+void
+kgdb_trgt_store_registers(int regno __unused)
+{
+	fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
+}