xref: /openbsd-src/sys/kern/init_main.c (revision 1b4a394fde7ee125bb7af82662ad3ea96d51265f)
1 /*	$OpenBSD: init_main.c,v 1.318 2022/10/30 17:43:40 guenther 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/errno.h>
44 #include <sys/kthread.h>
45 #include <sys/mount.h>
46 #include <sys/proc.h>
47 #include <sys/resourcevar.h>
48 #include <sys/signalvar.h>
49 #include <sys/systm.h>
50 #include <sys/namei.h>
51 #include <sys/vnode.h>
52 #include <sys/tty.h>
53 #include <sys/buf.h>
54 #include <sys/device.h>
55 #include <sys/socketvar.h>
56 #include <sys/lockf.h>
57 #include <sys/reboot.h>
58 #ifdef SYSVSHM
59 #include <sys/shm.h>
60 #endif
61 #ifdef SYSVSEM
62 #include <sys/sem.h>
63 #endif
64 #ifdef SYSVMSG
65 #include <sys/msg.h>
66 #endif
67 #include <sys/domain.h>
68 #include <sys/event.h>
69 #include <sys/msgbuf.h>
70 #include <sys/mbuf.h>
71 #include <sys/pipe.h>
72 #include <sys/witness.h>
73 #include <sys/smr.h>
74 
75 #include <sys/syscallargs.h>
76 
77 #include <uvm/uvm_extern.h>
78 
79 #include <net/if.h>
80 #include <net/rtable.h>
81 
82 #if defined(CRYPTO)
83 #include <crypto/cryptodev.h>
84 #include <crypto/cryptosoft.h>
85 #endif
86 
87 #if defined(KUBSAN)
88 extern void kubsan_init(void);
89 #endif
90 
91 #if defined(NFSSERVER) || defined(NFSCLIENT)
92 extern void nfs_init(void);
93 #endif
94 
95 #include "stoeplitz.h"
96 #if NSTOEPLITZ > 0
97 extern void stoeplitz_init(void);
98 #endif
99 
100 #include "mpath.h"
101 #include "vscsi.h"
102 #include "softraid.h"
103 
104 const char	copyright[] =
105 "Copyright (c) 1982, 1986, 1989, 1991, 1993\n"
106 "\tThe Regents of the University of California.  All rights reserved.\n"
107 "Copyright (c) 1995-2022 OpenBSD. All rights reserved.  https://www.OpenBSD.org\n";
108 
109 /* Components of the first process -- never freed. */
110 struct	session session0;
111 struct	pgrp pgrp0;
112 struct	proc proc0;
113 struct	process process0;
114 struct	plimit limit0;
115 struct	vmspace vmspace0;
116 struct	sigacts sigacts0;
117 struct	process *initprocess;
118 struct	proc *reaperproc;
119 
120 extern	struct user *proc0paddr;
121 
122 struct	vnode *rootvp, *swapdev_vp;
123 int	boothowto;
124 int	db_active = 0;
125 int	ncpus =  1;
126 int	ncpusfound = 1;			/* number of cpus we find */
127 volatile int start_init_exec;		/* semaphore for start_init() */
128 
129 #if !defined(NO_PROPOLICE)
130 long	__guard_local __attribute__((section(".openbsd.randomdata")));
131 #endif
132 
133 /* XXX return int so gcc -Werror won't complain */
134 int	main(void *);
135 void	check_console(struct proc *);
136 void	start_init(void *);
137 void	db_ctf_init(void);
138 void	prof_init(void);
139 void	init_exec(void);
140 void	futex_init(void);
141 void	taskq_init(void);
142 void	timeout_proc_init(void);
143 void	pool_gc_pages(void *);
144 void	percpu_init(void);
145 
146 #ifdef DIAGNOSTIC
147 int pdevinit_done = 0;
148 #endif
149 
150 /*
151  * System startup; initialize the world, create process 0, mount root
152  * filesystem, and fork to create init and pagedaemon.  Most of the
153  * hard work is done in the lower-level initialization routines including
154  * startup(), which does memory initialization and autoconfiguration.
155  */
156 /* XXX return int, so gcc -Werror won't complain */
157 int
158 main(void *framep)
159 {
160 	struct proc *p;
161 	struct process *pr;
162 	struct pdevinit *pdev;
163 	extern struct pdevinit pdevinit[];
164 	extern void disk_init(void);
165 
166 	/*
167 	 * Initialize the current process pointer (curproc) before
168 	 * any possible traps/probes to simplify trap processing.
169 	 */
170 	curproc = p = &proc0;
171 	p->p_cpu = curcpu();
172 
173 	/*
174 	 * Initialize timeouts.
175 	 */
176 	timeout_startup();
177 
178 	/*
179 	 * Attempt to find console and initialize
180 	 * in case of early panic or other messages.
181 	 */
182 	config_init();		/* init autoconfiguration data structures */
183 	consinit();
184 
185 	printf("%s\n", copyright);
186 
187 #ifdef KUBSAN
188 	/* Initialize kubsan. */
189 	kubsan_init();
190 #endif
191 
192 	WITNESS_INITIALIZE();
193 
194 	KERNEL_LOCK_INIT();
195 	SCHED_LOCK_INIT();
196 
197 	rw_obj_init();
198 	uvm_init();
199 	disk_init();		/* must come before autoconfiguration */
200 	tty_init();		/* initialise tty's */
201 	cpu_startup();
202 
203 	random_start(boothowto & RB_GOODRANDOM);	/* Start the flow */
204 
205 	/*
206 	 * Initialize mbuf's.  Do this now because we might attempt to
207 	 * allocate mbufs or mbuf clusters during autoconfiguration.
208 	 */
209 	mbinit();
210 
211 #if NSTOEPLITZ > 0
212 	stoeplitz_init();
213 #endif
214 
215 	/* Initialize sockets. */
216 	soinit();
217 
218 	/* Initialize SRP subsystem. */
219 	srp_startup();
220 
221 	/* Initialize SMR subsystem. */
222 	smr_startup();
223 
224 	/*
225 	 * Initialize process and pgrp structures.
226 	 */
227 	procinit();
228 
229 	/* Initialize file locking. */
230 	lf_init();
231 
232 	/*
233 	 * Initialize filedescriptors.
234 	 */
235 	filedesc_init();
236 
237 	/*
238 	 * Initialize pipes.
239 	 */
240 	pipe_init();
241 
242 	/*
243 	 * Initialize kqueues.
244 	 */
245 	kqueue_init();
246 
247 	/*
248 	 * Initialize futexes.
249 	 */
250 	futex_init();
251 
252 	/* Create credentials. */
253 	p->p_ucred = crget();
254 	p->p_ucred->cr_ngroups = 1;	/* group 0 */
255 
256 	/*
257 	 * Create process 0 (the swapper).
258 	 */
259 	pr = &process0;
260 	process_initialize(pr, p);
261 
262 	LIST_INSERT_HEAD(&allprocess, pr, ps_list);
263 	LIST_INSERT_HEAD(PIDHASH(0), pr, ps_hash);
264 	atomic_setbits_int(&pr->ps_flags, PS_SYSTEM);
265 
266 	/* Set the default routing table/domain. */
267 	process0.ps_rtableid = 0;
268 
269 	LIST_INSERT_HEAD(&allproc, p, p_list);
270 	pr->ps_pgrp = &pgrp0;
271 	LIST_INSERT_HEAD(TIDHASH(0), p, p_hash);
272 	LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
273 	LIST_INIT(&pgrp0.pg_members);
274 	LIST_INSERT_HEAD(&pgrp0.pg_members, pr, ps_pglist);
275 
276 	pgrp0.pg_session = &session0;
277 	session0.s_count = 1;
278 	session0.s_leader = pr;
279 
280 	atomic_setbits_int(&p->p_flag, P_SYSTEM);
281 	p->p_stat = SONPROC;
282 	pr->ps_nice = NZERO;
283 	strlcpy(pr->ps_comm, "swapper", sizeof(pr->ps_comm));
284 
285 	/* Init timeouts. */
286 	timeout_set(&p->p_sleep_to, endtsleep, p);
287 
288 	/* Initialize signal state for process 0. */
289 	signal_init();
290 	siginit(&sigacts0);
291 	pr->ps_sigacts = &sigacts0;
292 
293 	/* Create the file descriptor table. */
294 	p->p_fd = pr->ps_fd = fdinit();
295 
296 	/* Create the limits structures. */
297 	lim_startup(&limit0);
298 	pr->ps_limit = &limit0;
299 
300 	/* Allocate a prototype map so we have something to fork. */
301 	uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
302 	    trunc_page(VM_MAX_ADDRESS), TRUE, TRUE);
303 	p->p_vmspace = pr->ps_vmspace = &vmspace0;
304 
305 	p->p_addr = proc0paddr;				/* XXX */
306 
307 	/*
308 	 * Charge root for one process.
309 	 */
310 	(void)chgproccnt(0, 1);
311 
312 	/* Initialize run queues */
313 	sched_init_runqueues();
314 	sleep_queue_init();
315 	sched_init_cpu(curcpu());
316 	p->p_cpu->ci_randseed = (arc4random() & 0x7fffffff) + 1;
317 
318 	/* Initialize timeouts in process context. */
319 	timeout_proc_init();
320 
321 	/* Initialize task queues */
322 	taskq_init();
323 
324 	/* Initialize the interface/address trees */
325 	ifinit();
326 
327 	/* Lock the kernel on behalf of proc0. */
328 	KERNEL_LOCK();
329 
330 #if NMPATH > 0
331 	/* Attach mpath before hardware */
332 	config_rootfound("mpath", NULL);
333 #endif
334 
335 	/* Configure the devices */
336 	cpu_configure();
337 
338 	/* Configure virtual memory system, set vm rlimits. */
339 	uvm_init_limits(&limit0);
340 
341 	/* Per CPU memory allocation */
342 	percpu_init();
343 
344 	/* Initialize the file systems. */
345 #if defined(NFSSERVER) || defined(NFSCLIENT)
346 	nfs_init();			/* initialize server/shared data */
347 #endif
348 	vfsinit();
349 
350 	/* Start real time and statistics clocks. */
351 	initclocks();
352 
353 #ifdef SYSVSHM
354 	/* Initialize System V style shared memory. */
355 	shminit();
356 #endif
357 
358 #ifdef SYSVSEM
359 	/* Initialize System V style semaphores. */
360 	seminit();
361 #endif
362 
363 #ifdef SYSVMSG
364 	/* Initialize System V style message queues. */
365 	msginit();
366 #endif
367 
368 	/* Create default routing table before attaching lo0. */
369 	rtable_init();
370 
371 	/* Attach pseudo-devices. */
372 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
373 		if (pdev->pdev_count > 0)
374 			(*pdev->pdev_attach)(pdev->pdev_count);
375 #ifdef DIAGNOSTIC
376 	pdevinit_done = 1;
377 #endif
378 
379 #ifdef CRYPTO
380 	crypto_init();
381 	swcr_init();
382 #endif /* CRYPTO */
383 
384 	/*
385 	 * Initialize protocols.
386 	 */
387 	domaininit();
388 
389 	initconsbuf();
390 
391 #if defined(GPROF) || defined(DDBPROF)
392 	/* Initialize kernel profiling. */
393 	prof_init();
394 #endif
395 
396 	/* Enable per-CPU data. */
397 	mbcpuinit();
398 	kqueue_init_percpu();
399 	uvm_init_percpu();
400 
401 	/* init exec */
402 	init_exec();
403 
404 	/* Start the scheduler */
405 	scheduler_start();
406 
407 	/*
408 	 * Create process 1 (init(8)).  We do this now, as Unix has
409 	 * historically had init be process 1, and changing this would
410 	 * probably upset a lot of people.
411 	 *
412 	 * Note that process 1 won't immediately exec init(8), but will
413 	 * wait for us to inform it that the root file system has been
414 	 * mounted.
415 	 */
416 	{
417 		struct proc *initproc;
418 
419 		if (fork1(p, FORK_FORK, start_init, NULL, NULL, &initproc))
420 			panic("fork init");
421 		initprocess = initproc->p_p;
422 	}
423 
424 	/*
425 	 * Create any kernel threads whose creation was deferred because
426 	 * initprocess had not yet been created.
427 	 */
428 	kthread_run_deferred_queue();
429 
430 	/*
431 	 * Now that device driver threads have been created, wait for
432 	 * them to finish any deferred autoconfiguration.  Note we don't
433 	 * need to lock this semaphore, since we haven't booted any
434 	 * secondary processors, yet.
435 	 */
436 	while (config_pending)
437 		tsleep_nsec(&config_pending, PWAIT, "cfpend", INFSLP);
438 
439 	dostartuphooks();
440 
441 #if NVSCSI > 0
442 	config_rootfound("vscsi", NULL);
443 #endif
444 #if NSOFTRAID > 0
445 	config_rootfound("softraid", NULL);
446 #endif
447 
448 	/* Configure root/swap devices */
449 	diskconf();
450 
451 #ifdef DDB
452 	/* Make debug symbols available in ddb. */
453 	db_ctf_init();
454 #endif
455 
456 	if (mountroot == NULL || ((*mountroot)() != 0))
457 		panic("cannot mount root");
458 
459 	TAILQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
460 
461 	/* Get the vnode for '/'.  Set p->p_fd->fd_cdir to reference it. */
462 	if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode))
463 		panic("cannot find root vnode");
464 	p->p_fd->fd_cdir = rootvnode;
465 	vref(p->p_fd->fd_cdir);
466 	VOP_UNLOCK(rootvnode);
467 	p->p_fd->fd_rdir = NULL;
468 
469 	/*
470 	 * Now that root is mounted, we can fixup initprocess's CWD
471 	 * info.  All other processes are kthreads, which merely
472 	 * share proc0's CWD info.
473 	 */
474 	initprocess->ps_fd->fd_cdir = rootvnode;
475 	vref(initprocess->ps_fd->fd_cdir);
476 	initprocess->ps_fd->fd_rdir = NULL;
477 
478 	/*
479 	 * Now can look at time, having had a chance to verify the time
480 	 * from the file system.  Reset p->p_rtime as it may have been
481 	 * munched in mi_switch() after the time got set.
482 	 */
483 	LIST_FOREACH(pr, &allprocess, ps_list) {
484 		nanouptime(&pr->ps_start);
485 		TAILQ_FOREACH(p, &pr->ps_threads, p_thr_link) {
486 			nanouptime(&p->p_cpu->ci_schedstate.spc_runtime);
487 			timespecclear(&p->p_rtime);
488 		}
489 	}
490 
491 	uvm_swap_init();
492 
493 	/* Create the pageout daemon kernel thread. */
494 	if (kthread_create(uvm_pageout, NULL, NULL, "pagedaemon"))
495 		panic("fork pagedaemon");
496 
497 	/* Create the reaper daemon kernel thread. */
498 	if (kthread_create(reaper, NULL, &reaperproc, "reaper"))
499 		panic("fork reaper");
500 
501 	/* Create the cleaner daemon kernel thread. */
502 	if (kthread_create(buf_daemon, NULL, &cleanerproc, "cleaner"))
503 		panic("fork cleaner");
504 
505 	/* Create the update daemon kernel thread. */
506 	if (kthread_create(syncer_thread, NULL, &syncerproc, "update"))
507 		panic("fork update");
508 
509 	/* Create the aiodone daemon kernel thread. */
510 	if (kthread_create(uvm_aiodone_daemon, NULL, NULL, "aiodoned"))
511 		panic("fork aiodoned");
512 
513 #if !defined(__hppa__)
514 	/* Create the page zeroing kernel thread. */
515 	if (kthread_create(uvm_pagezero_thread, NULL, NULL, "zerothread"))
516 		panic("fork zerothread");
517 #endif
518 
519 #if defined(MULTIPROCESSOR)
520 	/* Boot the secondary processors. */
521 	cpu_boot_secondary_processors();
522 #endif
523 
524 	/* Now that all CPUs partake in scheduling, start SMR thread. */
525 	smr_startup_thread();
526 
527 	config_process_deferred_mountroot();
528 
529 	/*
530 	 * Okay, now we can let init(8) exec!  It's off to userland!
531 	 */
532 	start_init_exec = 1;
533 	wakeup((void *)&start_init_exec);
534 
535 	/*
536 	 * Start the idle pool page garbage collector
537 	 */
538 #if !(defined(__m88k__) && defined(MULTIPROCESSOR))	/* XXX */
539 	pool_gc_pages(NULL);
540 #endif
541 
542 	start_periodic_resettodr();
543 
544         /*
545          * proc0: nothing to do, back to sleep
546          */
547         while (1)
548                 tsleep_nsec(&proc0, PVM, "scheduler", INFSLP);
549 	/* NOTREACHED */
550 }
551 
552 /*
553  * List of paths to try when searching for "init".
554  */
555 static char *initpaths[] = {
556 	"/sbin/init",
557 	"/sbin/oinit",
558 	"/sbin/init.bak",
559 	NULL,
560 };
561 
562 void
563 check_console(struct proc *p)
564 {
565 	struct nameidata nd;
566 	int error;
567 
568 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p);
569 	error = namei(&nd);
570 	if (error) {
571 		if (error == ENOENT)
572 			printf("warning: /dev/console does not exist\n");
573 		else
574 			printf("warning: /dev/console error %d\n", error);
575 	} else
576 		vrele(nd.ni_vp);
577 }
578 
579 /*
580  * Start the initial user process; try exec'ing each pathname in "initpaths".
581  * The program is invoked with one argument containing the boot flags.
582  */
583 void
584 start_init(void *arg)
585 {
586 	struct proc *p = arg;
587 	vaddr_t addr;
588 	struct sys_execve_args /* {
589 		syscallarg(const char *) path;
590 		syscallarg(char *const *) argp;
591 		syscallarg(char *const *) envp;
592 	} */ args;
593 	int options, error;
594 	long i;
595 	register_t retval[2];
596 	char flags[4], *flagsp;
597 	char **pathp, *path, *ucp, **uap, *arg0, *arg1 = NULL;
598 
599 	/*
600 	 * Now in process 1.
601 	 */
602 
603 	/*
604 	 * Wait for main() to tell us that it's safe to exec.
605 	 */
606 	while (start_init_exec == 0)
607 		tsleep_nsec(&start_init_exec, PWAIT, "initexec", INFSLP);
608 
609 	check_console(p);
610 
611 	/* process 0 ignores SIGCHLD, but we can't */
612 	p->p_p->ps_sigacts->ps_sigflags = 0;
613 
614 	/*
615 	 * Need just enough stack to hold the faked-up "execve()" arguments.
616 	 */
617 #ifdef MACHINE_STACK_GROWS_UP
618 	addr = USRSTACK;
619 #else
620 	addr = USRSTACK - PAGE_SIZE;
621 #endif
622 	p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
623 	p->p_vmspace->vm_minsaddr = (caddr_t)(addr + PAGE_SIZE);
624 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
625 	    NULL, UVM_UNKNOWN_OFFSET, 0,
626 	    UVM_MAPFLAG(PROT_READ | PROT_WRITE, PROT_MASK, MAP_INHERIT_COPY,
627 	    MADV_NORMAL,
628 	    UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW|UVM_FLAG_STACK|UVM_FLAG_SYSCALL)))
629 		panic("init: couldn't allocate argument space");
630 
631 	for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) {
632 #ifdef MACHINE_STACK_GROWS_UP
633 		ucp = (char *)addr;
634 #else
635 		ucp = (char *)(addr + PAGE_SIZE);
636 #endif
637 		/*
638 		 * Construct the boot flag argument.
639 		 */
640 		flagsp = flags;
641 		*flagsp++ = '-';
642 		options = 0;
643 
644 		if (boothowto & RB_SINGLE) {
645 			*flagsp++ = 's';
646 			options = 1;
647 		}
648 #ifdef notyet
649 		if (boothowto & RB_FASTBOOT) {
650 			*flagsp++ = 'f';
651 			options = 1;
652 		}
653 #endif
654 
655 		/*
656 		 * Move out the flags (arg 1), if necessary.
657 		 */
658 		if (options != 0) {
659 			*flagsp++ = '\0';
660 			i = flagsp - flags;
661 #ifdef DEBUG
662 			printf("init: copying out flags `%s' %ld\n", flags, i);
663 #endif
664 #ifdef MACHINE_STACK_GROWS_UP
665 			arg1 = ucp;
666 			(void)copyout((caddr_t)flags, (caddr_t)ucp, i);
667 			ucp += i;
668 #else
669 			(void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i);
670 			arg1 = ucp;
671 #endif
672 		}
673 
674 		/*
675 		 * Move out the file name (also arg 0).
676 		 */
677 		i = strlen(path) + 1;
678 #ifdef DEBUG
679 		printf("init: copying out path `%s' %ld\n", path, i);
680 #endif
681 #ifdef MACHINE_STACK_GROWS_UP
682 		arg0 = ucp;
683 		(void)copyout((caddr_t)path, (caddr_t)ucp, i);
684 		ucp += i;
685 		ucp = (caddr_t)ALIGN((u_long)ucp);
686 		uap = (char **)ucp + 3;
687 #else
688 		(void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i);
689 		arg0 = ucp;
690 		uap = (char **)((u_long)ucp & ~ALIGNBYTES);
691 #endif
692 
693 		/*
694 		 * Move out the arg pointers.
695 		 */
696 		i = 0;
697 		copyout(&i, (caddr_t)--uap, sizeof(register_t)); /* terminator */
698 		if (options != 0)
699 			copyout(&arg1, (caddr_t)--uap, sizeof(register_t));
700 		copyout(&arg0, (caddr_t)--uap, sizeof(register_t));
701 
702 		/*
703 		 * Point at the arguments.
704 		 */
705 		SCARG(&args, path) = arg0;
706 		SCARG(&args, argp) = uap;
707 		SCARG(&args, envp) = NULL;
708 
709 		/*
710 		 * Now try to exec the program.  If can't for any reason
711 		 * other than it doesn't exist, complain.
712 		 */
713 		if ((error = sys_execve(p, &args, retval)) == EJUSTRETURN) {
714 			KERNEL_UNLOCK();
715 			return;
716 		}
717 		if (error != ENOENT)
718 			printf("exec %s: error %d\n", path, error);
719 	}
720 	printf("init: not found\n");
721 	panic("no init");
722 }
723