diff --git a/sys/kern/kern_shutdown.c b/sys/kern/kern_shutdown.c
new file mode 100644
index 000000000000..1c217becaecc
--- /dev/null
+++ b/sys/kern/kern_shutdown.c
@@ -0,0 +1,429 @@
+/*-
+ * Copyright (c) 1986, 1988, 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ * (c) UNIX System Laboratories, Inc.
+ * All or some portions of this file are derived from material licensed
+ * to the University of California by American Telephone and Telegraph
+ * Co. or Unix System Laboratories, Inc. and are reproduced herein with
+ * the permission of UNIX System Laboratories, Inc.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
+ *
+ *	@(#)kern_shutdown.c	8.3 (Berkeley) 1/21/94
+ * $Id: subr_prf.c,v 1.37 1996/05/09 18:58:06 gpalmer Exp $
+ */
+
+#include "opt_ddb.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/reboot.h>
+#include <sys/msgbuf.h>
+#include <sys/proc.h>
+#include <sys/vnode.h>
+#include <sys/tty.h>
+#include <sys/tprintf.h>
+#include <sys/syslog.h>
+#include <sys/malloc.h>
+#include <sys/kernel.h>
+#include <sys/sysctl.h>
+#include <sys/devconf.h>
+#include <sys/conf.h>
+#include <sys/sysproto.h>
+
+#include <machine/pcb.h>
+#include <machine/clock.h>
+#include <machine/cons.h>
+#include <machine/md_var.h>
+
+#include <sys/utsname.h>
+#include <sys/signalvar.h>
+
+#ifndef PANIC_REBOOT_WAIT_TIME
+#define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
+#endif
+
+/*
+ * Note that stdarg.h and the ANSI style va_start macro is used for both
+ * ANSI and traditional C compilers.
+ */
+#include <machine/stdarg.h>
+
+#if defined(DDB)
+#ifdef DDB_UNATTENDED
+	static int debugger_on_panic = 0;
+#else
+	static int debugger_on_panic = 1;
+#endif
+
+SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
+	&debugger_on_panic, 0, "");
+#endif
+
+
+/*
+ * Variable panicstr contains argument to first call to panic; used as flag
+ * to indicate that the kernel has already called panic.
+ */
+const char *panicstr;
+
+/*
+ * callout list for things to do a shutdown
+ */
+typedef struct shutdown_list_element {
+	struct shutdown_list_element *next;
+	bootlist_fn function;
+	void *arg;
+} *sle_p;
+
+static sle_p shutdown_list;
+
+
+
+/* This implements a "TEXT_SET" for cleanup functions */
+static void	dummy_cleanup __P((void));
+static void
+dummy_cleanup() {}
+TEXT_SET(cleanup_set, dummy_cleanup);
+
+typedef void (*cleanup_func_t)(void);
+extern const struct linker_set cleanup_set;
+static const cleanup_func_t *cleanups =
+        (const cleanup_func_t *)&cleanup_set.ls_items[0];
+static void dumpsys(void);
+
+#ifndef _SYS_SYSPROTO_H_
+struct reboot_args {
+	int	opt;
+};
+#endif
+/* ARGSUSED */
+
+/*
+ * The system call that results in a reboot
+ */
+int
+reboot(p, uap, retval)
+	struct proc *p;
+	struct reboot_args *uap;
+	int *retval;
+{
+	int error;
+
+	if ((error = suser(p->p_ucred, &p->p_acflag)))
+		return (error);
+
+	boot(uap->opt);
+	return (0);
+}
+
+/*
+ * Called by events that want to shut down.. e.g  <CTL><ALT><DEL> on a PC
+ */
+void
+shutdown_nice(void)
+{
+	/* Send a signal to init(8) and have it shutdown the world */
+	if (initproc != NULL) {
+		psignal(initproc, SIGINT);
+	} else {
+		/* No init(8) running, so simply reboot */
+		boot(RB_NOSYNC);
+	}
+	return;
+}
+static int	waittime = -1;
+static struct pcb dumppcb;
+
+/*
+ *  Go through the rigmarole of shutting down..
+ * this used to be in machdep.c but I'll be dammned if I could see
+ * anything machine dependant in it.
+ */
+__dead void
+boot(howto)
+	int howto;
+{
+	sle_p ep = shutdown_list;
+
+	/*
+	 * eventually the at_shutdown() method will totally replace the
+	 * linker set but for now leave them both (so 3rd partys
+	 * modules that might use it can not break).
+	 * The linker set is no good for LKMs etc.
+	 */
+	if ((howto & RB_NOSYNC) == 0 ) {
+		printf("\ncleaning up... ");
+                while(*cleanups) {
+			printf("Using obsolete shutdown callout..\n");
+			printf("update code to use at_shutdown()\n");
+                        (**cleanups++)();
+                }
+	}
+	while(ep) {
+		shutdown_list = ep->next;
+		(*ep->function)(howto, ep->arg);
+		ep = ep->next;
+	}
+	if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
+		register struct buf *bp;
+		int iter, nbusy;
+
+		waittime = 0;
+		printf("\nsyncing disks... ");
+
+		sync(&proc0, NULL, NULL);
+
+		for (iter = 0; iter < 20; iter++) {
+			nbusy = 0;
+			for (bp = &buf[nbuf]; --bp >= buf; ) {
+				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
+					nbusy++;
+				}
+			}
+			if (nbusy == 0)
+				break;
+			printf("%d ", nbusy);
+			DELAY(40000 * iter);
+		}
+		if (nbusy) {
+			/*
+			 * Failed to sync all blocks. Indicate this and don't
+			 * unmount filesystems (thus forcing an fsck on reboot).
+			 */
+			printf("giving up\n");
+#ifdef SHOW_BUSYBUFS
+			nbusy = 0;
+			for (bp = &buf[nbuf]; --bp >= buf; ) {
+				if ((bp->b_flags & (B_BUSY | B_INVAL)) == B_BUSY) {
+					nbusy++;
+					printf("%d: dev:%08x, flags:%08x, blkno:%d, lblkno:%d\n", nbusy, bp->b_dev, bp->b_flags, bp->b_blkno, bp->b_lblkno);
+				}
+			}
+			DELAY(5000000);	/* 5 seconds */
+#endif
+		} else {
+			printf("done\n");
+			/*
+			 * Unmount filesystems
+			 */
+			if (panicstr == 0)
+				vfs_unmountall();
+		}
+		DELAY(100000);			/* wait for console output to finish */
+		dev_shutdownall(FALSE);
+	}
+	splhigh();
+	if (howto & RB_HALT) {
+		printf("\n");
+		printf("The operating system has halted.\n");
+		printf("Please press any key to reboot.\n\n");
+		cngetc();
+	} else {
+		if (howto & RB_DUMP) {
+			if (!cold) {
+				savectx(&dumppcb);
+				dumppcb.pcb_cr3 = rcr3();
+				dumpsys();
+			}
+
+			if (PANIC_REBOOT_WAIT_TIME != 0) {
+				if (PANIC_REBOOT_WAIT_TIME != -1) {
+					int loop;
+					printf("Automatic reboot in %d seconds - press a key on the console to abort\n",
+						PANIC_REBOOT_WAIT_TIME);
+					for (loop = PANIC_REBOOT_WAIT_TIME * 10; loop > 0; --loop) {
+						DELAY(1000 * 100); /* 1/10th second */
+						if (cncheckc()) /* Did user type a key? */
+							break;
+					}
+					if (!loop)
+						goto die;
+				}
+			} else { /* zero time specified - reboot NOW */
+				goto die;
+			}
+			printf("--> Press a key on the console to reboot <--\n");
+			cngetc();
+		}
+	}
+die:
+	printf("Rebooting...\n");
+	DELAY(1000000);	/* wait 1 sec for printf's to complete and be read */
+	cpu_reset();
+	for(;;) ;
+	/* NOTREACHED */
+}
+
+/*
+ * Magic number for savecore
+ *
+ * exported (symorder) and used at least by savecore(8)
+ *
+ */
+static u_long const	dumpmag = 0x8fca0101UL;	
+
+static int	dumpsize = 0;		/* also for savecore */
+
+static int	dodump = 1;
+SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, "");
+
+/*
+ * Doadump comes here after turning off memory management and
+ * getting on the dump stack, either when called above, or by
+ * the auto-restart code.
+ */
+static void
+dumpsys(void)
+{
+
+	if (!dodump)
+		return;
+	if (dumpdev == NODEV)
+		return;
+	if ((minor(dumpdev)&07) != 1)
+		return;
+	if (!(bdevsw[major(dumpdev)]))
+		return;
+	if (!(bdevsw[major(dumpdev)]->d_dump))
+		return;
+	dumpsize = Maxmem;
+	printf("\ndumping to dev %lx, offset %ld\n", dumpdev, dumplo);
+	printf("dump ");
+	switch ((*bdevsw[major(dumpdev)]->d_dump)(dumpdev)) {
+
+	case ENXIO:
+		printf("device bad\n");
+		break;
+
+	case EFAULT:
+		printf("device not ready\n");
+		break;
+
+	case EINVAL:
+		printf("area improper\n");
+		break;
+
+	case EIO:
+		printf("i/o error\n");
+		break;
+
+	case EINTR:
+		printf("aborted from console\n");
+		break;
+
+	default:
+		printf("succeeded\n");
+		break;
+	}
+}
+
+/*
+ * Panic is called on unresolvable fatal errors.  It prints "panic: mesg",
+ * and then reboots.  If we are called twice, then we avoid trying to sync
+ * the disks as this often leads to recursive panics.
+ */
+#ifdef __GNUC__
+__dead			/* panic() does not return */
+#endif
+void
+panic(const char *fmt, ...)
+{
+	int bootopt;
+	va_list ap;
+
+	bootopt = RB_AUTOBOOT | RB_DUMP;
+	if (panicstr)
+		bootopt |= RB_NOSYNC;
+	else
+		panicstr = fmt;
+
+	printf("panic: ");
+	va_start(ap, fmt);
+	vprintf(fmt, ap);
+	va_end(ap);
+	printf("\n");
+
+#if defined(DDB)
+	if (debugger_on_panic)
+		Debugger ("panic");
+#endif
+	boot(bootopt);
+}
+
+
+/*********************************************************
+ * general routines to handle adding/deleting items on the
+ * shutdown callout list
+ *****
+ * Take the arguments given and put them onto the shutdown callout list.
+ * However first make sure that it's not already there.
+ * returns 0 on success.
+ */
+int
+at_shutdown(bootlist_fn function, void *arg)
+{
+	sle_p ep;
+	if(rm_at_shutdown(function, arg)) {
+		printf("exit callout entry already present\n");
+	}
+	ep = malloc(sizeof(*ep),M_TEMP,M_NOWAIT);
+	if(!ep) return ENOMEM;
+	ep->next = shutdown_list;
+	ep->function = function;
+	ep->arg = arg;
+	shutdown_list = ep;
+	return 0;
+}
+/*
+ * Scan the exit callout list for the given items and remove them.
+ * Returns the number of items removed.
+ */
+int
+rm_at_shutdown(bootlist_fn function, void *arg)
+{
+	sle_p *epp,ep;
+	int count = 0;
+
+	epp = &shutdown_list;
+	ep = *epp;
+	while(ep) {
+		if((ep->function == function) && (ep->arg = arg)) {
+			*epp = ep->next;
+			free(ep,M_TEMP);
+			count++;
+		} else {
+			epp = &ep->next;
+		}
+		ep = *epp;
+	}
+	return count;
+}
+
+
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index 36099e9af30e..8a4ccc2bbeb5 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)systm.h	8.7 (Berkeley) 3/29/95
- * $Id: systm.h,v 1.39 1996/05/08 04:29:01 gpalmer Exp $
+ * $Id: systm.h,v 1.40 1996/07/01 18:12:13 bde Exp $
  */
 
 #ifndef _SYS_SYSTM_H_
@@ -117,6 +117,7 @@ void	*phashinit __P((int count, int type, u_long *nentries));
 
 __dead void	panic __P((const char *, ...)) __dead2;
 __dead void	boot __P((int)) __dead2;
+__dead void	cpu_boot __P((int)) __dead2;
 void	tablefull __P((const char *));
 int	addlog __P((const char *, ...));
 int	kvprintf __P((char const *, void (*)(int, void*), void *, int, va_list));
@@ -188,4 +189,20 @@ void timeout(timeout_func_t, void *, int);
 void untimeout(timeout_func_t, void *);
 void	logwakeup __P((void));
 
+/* Various other callout lists that modules might want to know about */
+/* shutdown */
+typedef void (*bootlist_fn)(int,void *);
+int at_shutdown(bootlist_fn function, void *arg);
+int rm_at_shutdown(bootlist_fn function, void *arg);
+
+/* forking */ /* XXX not yet */
+typedef void (*forklist_fn)(struct proc *parent,struct proc *child,int flags);
+int at_fork(forklist_fn function);
+int rm_at_fork(forklist_fn function);
+
+/* exiting */
+typedef void (*exitlist_fn)(struct proc *procp);
+int at_exit(exitlist_fn function);
+int rm_at_exit(exitlist_fn function);
+
 #endif /* !_SYS_SYSTM_H_ */