xref: /openbsd-src/sys/kern/init_main.c (revision 7350f337b9e3eb4461d99580e625c7ef148d107c)
1 /*	$OpenBSD: init_main.c,v 1.290 2019/06/21 09:39:48 visa Exp $	*/
2 /*	$NetBSD: init_main.c,v 1.84.4.1 1996/06/02 09:08:06 mrg Exp $	*/
3 
4 /*
5  * Copyright (c) 1995 Christopher G. Demetriou.  All rights reserved.
6  * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  * (c) UNIX System Laboratories, Inc.
9  * All or some portions of this file are derived from material licensed
10  * to the University of California by American Telephone and Telegraph
11  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
12  * the permission of UNIX System Laboratories, Inc.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 3. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *	@(#)init_main.c	8.9 (Berkeley) 1/21/94
39  */
40 
41 #include <sys/param.h>
42 #include <sys/filedesc.h>
43 #include <sys/file.h>
44 #include <sys/errno.h>
45 #include <sys/exec.h>
46 #include <sys/kernel.h>
47 #include <sys/kthread.h>
48 #include <sys/mount.h>
49 #include <sys/proc.h>
50 #include <sys/resourcevar.h>
51 #include <sys/signalvar.h>
52 #include <sys/systm.h>
53 #include <sys/namei.h>
54 #include <sys/vnode.h>
55 #include <sys/tty.h>
56 #include <sys/conf.h>
57 #include <sys/buf.h>
58 #include <sys/device.h>
59 #include <sys/socketvar.h>
60 #include <sys/lockf.h>
61 #include <sys/protosw.h>
62 #include <sys/reboot.h>
63 #include <sys/user.h>
64 #ifdef SYSVSHM
65 #include <sys/shm.h>
66 #endif
67 #ifdef SYSVSEM
68 #include <sys/sem.h>
69 #endif
70 #ifdef SYSVMSG
71 #include <sys/msg.h>
72 #endif
73 #include <sys/domain.h>
74 #include <sys/msgbuf.h>
75 #include <sys/mbuf.h>
76 #include <sys/pipe.h>
77 #include <sys/task.h>
78 #include <sys/witness.h>
79 #include <sys/smr.h>
80 
81 #include <sys/syscall.h>
82 #include <sys/syscallargs.h>
83 
84 #include <uvm/uvm_extern.h>
85 
86 #include <dev/rndvar.h>
87 
88 #include <ufs/ufs/quota.h>
89 
90 #include <net/if.h>
91 #include <net/rtable.h>
92 #include <net/netisr.h>
93 
94 #if defined(CRYPTO)
95 #include <crypto/cryptodev.h>
96 #include <crypto/cryptosoft.h>
97 #endif
98 
99 #if defined(KUBSAN)
100 extern void kubsan_init(void);
101 extern void kubsan_start(void);
102 #endif
103 
104 #if defined(NFSSERVER) || defined(NFSCLIENT)
105 extern void nfs_init(void);
106 #endif
107 
108 #include "mpath.h"
109 #include "vscsi.h"
110 #include "softraid.h"
111 
112 const char	copyright[] =
113 "Copyright (c) 1982, 1986, 1989, 1991, 1993\n"
114 "\tThe Regents of the University of California.  All rights reserved.\n"
115 "Copyright (c) 1995-2019 OpenBSD. All rights reserved.  https://www.OpenBSD.org\n";
116 
117 /* Components of the first process -- never freed. */
118 struct	session session0;
119 struct	pgrp pgrp0;
120 struct	proc proc0;
121 struct	process process0;
122 struct	plimit limit0;
123 struct	vmspace vmspace0;
124 struct	sigacts sigacts0;
125 struct	process *initprocess;
126 struct	proc *reaperproc;
127 
128 extern	struct user *proc0paddr;
129 
130 struct	vnode *rootvp, *swapdev_vp;
131 int	boothowto;
132 int	db_active = 0;
133 int	ncpus =  1;
134 int	ncpusfound = 1;			/* number of cpus we find */
135 volatile int start_init_exec;		/* semaphore for start_init() */
136 
137 #if !defined(NO_PROPOLICE)
138 long	__guard_local __attribute__((section(".openbsd.randomdata")));
139 #endif
140 
141 /* XXX return int so gcc -Werror won't complain */
142 int	main(void *);
143 void	check_console(struct proc *);
144 void	start_init(void *);
145 void	crypto_init(void);
146 void	db_ctf_init(void);
147 void	prof_init(void);
148 void	init_exec(void);
149 void	kqueue_init(void);
150 void	futex_init(void);
151 void	taskq_init(void);
152 void	timeout_proc_init(void);
153 void	pool_gc_pages(void *);
154 void	percpu_init(void);
155 
156 extern char sigcode[], esigcode[], sigcoderet[];
157 #ifdef SYSCALL_DEBUG
158 extern char *syscallnames[];
159 #endif
160 
161 struct emul emul_native = {
162 	"native",
163 	NULL,
164 	SYS_syscall,
165 	SYS_MAXSYSCALL,
166 	sysent,
167 #ifdef SYSCALL_DEBUG
168 	syscallnames,
169 #else
170 	NULL,
171 #endif
172 	0,
173 	copyargs,
174 	setregs,
175 	NULL,		/* fixup */
176 	NULL,		/* coredump */
177 	sigcode,
178 	esigcode,
179 	sigcoderet
180 };
181 
182 #ifdef DIAGNOSTIC
183 int pdevinit_done = 0;
184 #endif
185 
186 /*
187  * System startup; initialize the world, create process 0, mount root
188  * filesystem, and fork to create init and pagedaemon.  Most of the
189  * hard work is done in the lower-level initialization routines including
190  * startup(), which does memory initialization and autoconfiguration.
191  */
192 /* XXX return int, so gcc -Werror won't complain */
193 int
194 main(void *framep)
195 {
196 	struct proc *p;
197 	struct process *pr;
198 	struct pdevinit *pdev;
199 	extern struct pdevinit pdevinit[];
200 	extern void disk_init(void);
201 
202 	/*
203 	 * Initialize the current process pointer (curproc) before
204 	 * any possible traps/probes to simplify trap processing.
205 	 */
206 	curproc = p = &proc0;
207 	p->p_cpu = curcpu();
208 
209 	/*
210 	 * Initialize timeouts.
211 	 */
212 	timeout_startup();
213 
214 	/*
215 	 * Attempt to find console and initialize
216 	 * in case of early panic or other messages.
217 	 */
218 	config_init();		/* init autoconfiguration data structures */
219 	consinit();
220 
221 	printf("%s\n", copyright);
222 
223 #ifdef KUBSAN
224 	/* Initialize kubsan. */
225 	kubsan_init();
226 #endif
227 
228 	WITNESS_INITIALIZE();
229 
230 	KERNEL_LOCK_INIT();
231 	SCHED_LOCK_INIT();
232 
233 	uvm_init();
234 	disk_init();		/* must come before autoconfiguration */
235 	tty_init();		/* initialise tty's */
236 	cpu_startup();
237 
238 	random_start();		/* Start the flow */
239 
240 	/*
241 	 * Initialize mbuf's.  Do this now because we might attempt to
242 	 * allocate mbufs or mbuf clusters during autoconfiguration.
243 	 */
244 	mbinit();
245 
246 	/* Initialize sockets. */
247 	soinit();
248 
249 	/* Initialize SRP subsystem. */
250 	srp_startup();
251 
252 	/* Initialize SMR subsystem. */
253 	smr_startup();
254 
255 	/*
256 	 * Initialize process and pgrp structures.
257 	 */
258 	procinit();
259 
260 	/* Initialize file locking. */
261 	lf_init();
262 
263 	/*
264 	 * Initialize filedescriptors.
265 	 */
266 	filedesc_init();
267 
268 	/*
269 	 * Initialize pipes.
270 	 */
271 	pipe_init();
272 
273 	/*
274 	 * Initialize kqueues.
275 	 */
276 	kqueue_init();
277 
278 	/*
279 	 * Initialize futexes.
280 	 */
281 	futex_init();
282 
283 	/* Create credentials. */
284 	p->p_ucred = crget();
285 	p->p_ucred->cr_ngroups = 1;	/* group 0 */
286 
287 	/*
288 	 * Create process 0 (the swapper).
289 	 */
290 	pr = &process0;
291 	process_initialize(pr, p);
292 
293 	LIST_INSERT_HEAD(&allprocess, pr, ps_list);
294 	LIST_INSERT_HEAD(PIDHASH(0), pr, ps_hash);
295 	atomic_setbits_int(&pr->ps_flags, PS_SYSTEM);
296 
297 	/* Set the default routing table/domain. */
298 	process0.ps_rtableid = 0;
299 
300 	LIST_INSERT_HEAD(&allproc, p, p_list);
301 	pr->ps_pgrp = &pgrp0;
302 	LIST_INSERT_HEAD(TIDHASH(0), p, p_hash);
303 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
304 	LIST_INIT(&pgrp0.pg_members);
305 	LIST_INSERT_HEAD(&pgrp0.pg_members, pr, ps_pglist);
306 
307 	pgrp0.pg_session = &session0;
308 	session0.s_count = 1;
309 	session0.s_leader = pr;
310 
311 	atomic_setbits_int(&p->p_flag, P_SYSTEM);
312 	p->p_stat = SONPROC;
313 	pr->ps_nice = NZERO;
314 	pr->ps_emul = &emul_native;
315 	strlcpy(pr->ps_comm, "swapper", sizeof(pr->ps_comm));
316 
317 	/* Init timeouts. */
318 	timeout_set(&p->p_sleep_to, endtsleep, p);
319 
320 	/* Initialize signal state for process 0. */
321 	signal_init();
322 	pr->ps_sigacts = &sigacts0;
323 	siginit(pr);
324 
325 	/* Create the file descriptor table. */
326 	p->p_fd = pr->ps_fd = fdinit();
327 
328 	/* Create the limits structures. */
329 	lim_startup(&limit0);
330 	pr->ps_limit = &limit0;
331 
332 	/* Allocate a prototype map so we have something to fork. */
333 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
334 	    trunc_page(VM_MAX_ADDRESS), TRUE, TRUE);
335 	p->p_vmspace = pr->ps_vmspace = &vmspace0;
336 
337 	p->p_addr = proc0paddr;				/* XXX */
338 
339 	/*
340 	 * Charge root for one process.
341 	 */
342 	(void)chgproccnt(0, 1);
343 
344 	/* Initialize run queues */
345 	sched_init_runqueues();
346 	sleep_queue_init();
347 	sched_init_cpu(curcpu());
348 	p->p_cpu->ci_randseed = (arc4random() & 0x7fffffff) + 1;
349 
350 	/* Initialize timeouts in process context. */
351 	timeout_proc_init();
352 
353 	/* Initialize task queues */
354 	taskq_init();
355 
356 #ifdef KUBSAN
357 	/* Start reporting kubsan findings. */
358 	kubsan_start();
359 #endif
360 
361 	/* Initialize the interface/address trees */
362 	ifinit();
363 
364 	/* Lock the kernel on behalf of proc0. */
365 	KERNEL_LOCK();
366 
367 #if NMPATH > 0
368 	/* Attach mpath before hardware */
369 	config_rootfound("mpath", NULL);
370 #endif
371 
372 	/* Configure the devices */
373 	cpu_configure();
374 
375 	/* Configure virtual memory system, set vm rlimits. */
376 	uvm_init_limits(&limit0);
377 
378 	/* Per CPU memory allocation */
379 	percpu_init();
380 
381 	/* Initialize the file systems. */
382 #if defined(NFSSERVER) || defined(NFSCLIENT)
383 	nfs_init();			/* initialize server/shared data */
384 #endif
385 	vfsinit();
386 
387 	/* Start real time and statistics clocks. */
388 	initclocks();
389 
390 #ifdef SYSVSHM
391 	/* Initialize System V style shared memory. */
392 	shminit();
393 #endif
394 
395 #ifdef SYSVSEM
396 	/* Initialize System V style semaphores. */
397 	seminit();
398 #endif
399 
400 #ifdef SYSVMSG
401 	/* Initialize System V style message queues. */
402 	msginit();
403 #endif
404 
405 	/* Create default routing table before attaching lo0. */
406 	rtable_init();
407 
408 	/* Attach pseudo-devices. */
409 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
410 		if (pdev->pdev_count > 0)
411 			(*pdev->pdev_attach)(pdev->pdev_count);
412 #ifdef DIAGNOSTIC
413 	pdevinit_done = 1;
414 #endif
415 
416 #ifdef CRYPTO
417 	crypto_init();
418 	swcr_init();
419 #endif /* CRYPTO */
420 
421 	/*
422 	 * Initialize protocols.
423 	 */
424 	domaininit();
425 
426 	initconsbuf();
427 
428 #if defined(GPROF) || defined(DDBPROF)
429 	/* Initialize kernel profiling. */
430 	prof_init();
431 #endif
432 
433 	mbcpuinit();	/* enable per cpu mbuf data */
434 
435 	/* init exec and emul */
436 	init_exec();
437 
438 	/* Start the scheduler */
439 	scheduler_start();
440 
441 	/*
442 	 * Create process 1 (init(8)).  We do this now, as Unix has
443 	 * historically had init be process 1, and changing this would
444 	 * probably upset a lot of people.
445 	 *
446 	 * Note that process 1 won't immediately exec init(8), but will
447 	 * wait for us to inform it that the root file system has been
448 	 * mounted.
449 	 */
450 	{
451 		struct proc *initproc;
452 
453 		if (fork1(p, FORK_FORK, start_init, NULL, NULL, &initproc))
454 			panic("fork init");
455 		initprocess = initproc->p_p;
456 	}
457 
458 	randompid = 1;
459 
460 	/*
461 	 * Create any kernel threads whose creation was deferred because
462 	 * initprocess had not yet been created.
463 	 */
464 	kthread_run_deferred_queue();
465 
466 	/*
467 	 * Now that device driver threads have been created, wait for
468 	 * them to finish any deferred autoconfiguration.  Note we don't
469 	 * need to lock this semaphore, since we haven't booted any
470 	 * secondary processors, yet.
471 	 */
472 	while (config_pending)
473 		(void) tsleep((void *)&config_pending, PWAIT, "cfpend", 0);
474 
475 	dostartuphooks();
476 
477 #if NVSCSI > 0
478 	config_rootfound("vscsi", NULL);
479 #endif
480 #if NSOFTRAID > 0
481 	config_rootfound("softraid", NULL);
482 #endif
483 
484 	/* Configure root/swap devices */
485 	diskconf();
486 
487 #ifdef DDB
488 	/* Make debug symbols available in ddb. */
489 	db_ctf_init();
490 #endif
491 
492 	if (mountroot == NULL || ((*mountroot)() != 0))
493 		panic("cannot mount root");
494 
495 	TAILQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
496 
497 	/* Get the vnode for '/'.  Set p->p_fd->fd_cdir to reference it. */
498 	if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode))
499 		panic("cannot find root vnode");
500 	p->p_fd->fd_cdir = rootvnode;
501 	vref(p->p_fd->fd_cdir);
502 	VOP_UNLOCK(rootvnode);
503 	p->p_fd->fd_rdir = NULL;
504 
505 	/*
506 	 * Now that root is mounted, we can fixup initprocess's CWD
507 	 * info.  All other processes are kthreads, which merely
508 	 * share proc0's CWD info.
509 	 */
510 	initprocess->ps_fd->fd_cdir = rootvnode;
511 	vref(initprocess->ps_fd->fd_cdir);
512 	initprocess->ps_fd->fd_rdir = NULL;
513 
514 	/*
515 	 * Now can look at time, having had a chance to verify the time
516 	 * from the file system.  Reset p->p_rtime as it may have been
517 	 * munched in mi_switch() after the time got set.
518 	 */
519 	LIST_FOREACH(pr, &allprocess, ps_list) {
520 		getnanotime(&pr->ps_start);
521 		TAILQ_FOREACH(p, &pr->ps_threads, p_thr_link) {
522 			nanouptime(&p->p_cpu->ci_schedstate.spc_runtime);
523 			timespecclear(&p->p_rtime);
524 		}
525 	}
526 
527 	uvm_swap_init();
528 
529 	/* Create the pageout daemon kernel thread. */
530 	if (kthread_create(uvm_pageout, NULL, NULL, "pagedaemon"))
531 		panic("fork pagedaemon");
532 
533 	/* Create the reaper daemon kernel thread. */
534 	if (kthread_create(reaper, NULL, &reaperproc, "reaper"))
535 		panic("fork reaper");
536 
537 	/* Create the cleaner daemon kernel thread. */
538 	if (kthread_create(buf_daemon, NULL, &cleanerproc, "cleaner"))
539 		panic("fork cleaner");
540 
541 	/* Create the update daemon kernel thread. */
542 	if (kthread_create(syncer_thread, NULL, &syncerproc, "update"))
543 		panic("fork update");
544 
545 	/* Create the aiodone daemon kernel thread. */
546 	if (kthread_create(uvm_aiodone_daemon, NULL, NULL, "aiodoned"))
547 		panic("fork aiodoned");
548 
549 #if !defined(__hppa__)
550 	/* Create the page zeroing kernel thread. */
551 	if (kthread_create(uvm_pagezero_thread, NULL, NULL, "zerothread"))
552 		panic("fork zerothread");
553 #endif
554 
555 #if defined(MULTIPROCESSOR)
556 	/* Boot the secondary processors. */
557 	cpu_boot_secondary_processors();
558 #endif
559 
560 	config_process_deferred_mountroot();
561 
562 	/*
563 	 * Okay, now we can let init(8) exec!  It's off to userland!
564 	 */
565 	start_init_exec = 1;
566 	wakeup((void *)&start_init_exec);
567 
568 	/*
569 	 * Start the idle pool page garbage collector
570 	 */
571 #if !(defined(__m88k__) && defined(MULTIPROCESSOR))	/* XXX */
572 	pool_gc_pages(NULL);
573 #endif
574 
575 	start_periodic_resettodr();
576 
577         /*
578          * proc0: nothing to do, back to sleep
579          */
580         while (1)
581                 tsleep(&proc0, PVM, "scheduler", 0);
582 	/* NOTREACHED */
583 }
584 
585 /*
586  * List of paths to try when searching for "init".
587  */
588 static char *initpaths[] = {
589 	"/sbin/init",
590 	"/sbin/oinit",
591 	"/sbin/init.bak",
592 	NULL,
593 };
594 
595 void
596 check_console(struct proc *p)
597 {
598 	struct nameidata nd;
599 	int error;
600 
601 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p);
602 	error = namei(&nd);
603 	if (error) {
604 		if (error == ENOENT)
605 			printf("warning: /dev/console does not exist\n");
606 		else
607 			printf("warning: /dev/console error %d\n", error);
608 	} else
609 		vrele(nd.ni_vp);
610 }
611 
612 /*
613  * Start the initial user process; try exec'ing each pathname in "initpaths".
614  * The program is invoked with one argument containing the boot flags.
615  */
616 void
617 start_init(void *arg)
618 {
619 	struct proc *p = arg;
620 	vaddr_t addr;
621 	struct sys_execve_args /* {
622 		syscallarg(const char *) path;
623 		syscallarg(char *const *) argp;
624 		syscallarg(char *const *) envp;
625 	} */ args;
626 	int options, error;
627 	long i;
628 	register_t retval[2];
629 	char flags[4], *flagsp;
630 	char **pathp, *path, *ucp, **uap, *arg0, *arg1 = NULL;
631 
632 	/*
633 	 * Now in process 1.
634 	 */
635 
636 	/*
637 	 * Wait for main() to tell us that it's safe to exec.
638 	 */
639 	while (start_init_exec == 0)
640 		(void) tsleep((void *)&start_init_exec, PWAIT, "initexec", 0);
641 
642 	check_console(p);
643 
644 	/* process 0 ignores SIGCHLD, but we can't */
645 	p->p_p->ps_sigacts->ps_flags = 0;
646 
647 	/*
648 	 * Need just enough stack to hold the faked-up "execve()" arguments.
649 	 */
650 #ifdef MACHINE_STACK_GROWS_UP
651 	addr = USRSTACK;
652 #else
653 	addr = USRSTACK - PAGE_SIZE;
654 #endif
655 	p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
656 	p->p_vmspace->vm_minsaddr = (caddr_t)(addr + PAGE_SIZE);
657 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
658 	    NULL, UVM_UNKNOWN_OFFSET, 0,
659 	    UVM_MAPFLAG(PROT_READ | PROT_WRITE, PROT_MASK, MAP_INHERIT_COPY,
660 	    MADV_NORMAL, UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW|UVM_FLAG_STACK)))
661 		panic("init: couldn't allocate argument space");
662 
663 	for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
664 #ifdef MACHINE_STACK_GROWS_UP
665 		ucp = (char *)addr;
666 #else
667 		ucp = (char *)(addr + PAGE_SIZE);
668 #endif
669 		/*
670 		 * Construct the boot flag argument.
671 		 */
672 		flagsp = flags;
673 		*flagsp++ = '-';
674 		options = 0;
675 
676 		if (boothowto & RB_SINGLE) {
677 			*flagsp++ = 's';
678 			options = 1;
679 		}
680 #ifdef notyet
681 		if (boothowto & RB_FASTBOOT) {
682 			*flagsp++ = 'f';
683 			options = 1;
684 		}
685 #endif
686 
687 		/*
688 		 * Move out the flags (arg 1), if necessary.
689 		 */
690 		if (options != 0) {
691 			*flagsp++ = '\0';
692 			i = flagsp - flags;
693 #ifdef DEBUG
694 			printf("init: copying out flags `%s' %ld\n", flags, i);
695 #endif
696 #ifdef MACHINE_STACK_GROWS_UP
697 			arg1 = ucp;
698 			(void)copyout((caddr_t)flags, (caddr_t)ucp, i);
699 			ucp += i;
700 #else
701 			(void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i);
702 			arg1 = ucp;
703 #endif
704 		}
705 
706 		/*
707 		 * Move out the file name (also arg 0).
708 		 */
709 		i = strlen(path) + 1;
710 #ifdef DEBUG
711 		printf("init: copying out path `%s' %ld\n", path, i);
712 #endif
713 #ifdef MACHINE_STACK_GROWS_UP
714 		arg0 = ucp;
715 		(void)copyout((caddr_t)path, (caddr_t)ucp, i);
716 		ucp += i;
717 		ucp = (caddr_t)ALIGN((u_long)ucp);
718 		uap = (char **)ucp + 3;
719 #else
720 		(void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i);
721 		arg0 = ucp;
722 		uap = (char **)((u_long)ucp & ~ALIGNBYTES);
723 #endif
724 
725 		/*
726 		 * Move out the arg pointers.
727 		 */
728 		i = 0;
729 		copyout(&i, (caddr_t)--uap, sizeof(register_t)); /* terminator */
730 		if (options != 0)
731 			copyout(&arg1, (caddr_t)--uap, sizeof(register_t));
732 		copyout(&arg0, (caddr_t)--uap, sizeof(register_t));
733 
734 		/*
735 		 * Point at the arguments.
736 		 */
737 		SCARG(&args, path) = arg0;
738 		SCARG(&args, argp) = uap;
739 		SCARG(&args, envp) = NULL;
740 
741 		/*
742 		 * Now try to exec the program.  If can't for any reason
743 		 * other than it doesn't exist, complain.
744 		 */
745 		if ((error = sys_execve(p, &args, retval)) == 0) {
746 			KERNEL_UNLOCK();
747 			return;
748 		}
749 		if (error != ENOENT)
750 			printf("exec %s: error %d\n", path, error);
751 	}
752 	printf("init: not found\n");
753 	panic("no init");
754 }
755