xref: /netbsd-src/sys/kern/init_main.c (revision f81322cf185a4db50f71fcf7701f20198272620e)
1 /*	$NetBSD: init_main.c,v 1.263 2006/03/07 03:32:06 thorpej Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)init_main.c	8.16 (Berkeley) 5/14/95
37  */
38 
39 /*
40  * Copyright (c) 1995 Christopher G. Demetriou.  All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by the University of
53  *	California, Berkeley and its contributors.
54  * 4. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  *
70  *	@(#)init_main.c	8.16 (Berkeley) 5/14/95
71  */
72 
73 #include <sys/cdefs.h>
74 __KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.263 2006/03/07 03:32:06 thorpej Exp $");
75 
76 #include "opt_ipsec.h"
77 #include "opt_sysv.h"
78 #include "opt_maxuprc.h"
79 #include "opt_multiprocessor.h"
80 #include "opt_pipe.h"
81 #include "opt_syscall_debug.h"
82 #include "opt_posix.h"
83 #include "opt_kcont.h"
84 #include "opt_verified_exec.h"
85 
86 #include "rnd.h"
87 
88 #include <sys/param.h>
89 #include <sys/acct.h>
90 #include <sys/filedesc.h>
91 #include <sys/file.h>
92 #include <sys/errno.h>
93 #include <sys/callout.h>
94 #include <sys/kernel.h>
95 #include <sys/kcont.h>
96 #include <sys/mount.h>
97 #include <sys/proc.h>
98 #include <sys/kthread.h>
99 #include <sys/resourcevar.h>
100 #include <sys/signalvar.h>
101 #include <sys/systm.h>
102 #include <sys/vnode.h>
103 #include <sys/tty.h>
104 #include <sys/conf.h>
105 #include <sys/disklabel.h>
106 #include <sys/buf.h>
107 #include <sys/device.h>
108 #include <sys/exec.h>
109 #include <sys/socketvar.h>
110 #include <sys/protosw.h>
111 #include <sys/reboot.h>
112 #include <sys/user.h>
113 #include <sys/sysctl.h>
114 #include <sys/event.h>
115 #include <sys/mbuf.h>
116 #ifdef FAST_IPSEC
117 #include <netipsec/ipsec.h>
118 #endif
119 #ifdef SYSVSHM
120 #include <sys/shm.h>
121 #endif
122 #ifdef SYSVSEM
123 #include <sys/sem.h>
124 #endif
125 #ifdef SYSVMSG
126 #include <sys/msg.h>
127 #endif
128 #ifdef P1003_1B_SEMAPHORE
129 #include <sys/ksem.h>
130 #endif
131 #include <sys/domain.h>
132 #include <sys/namei.h>
133 #if NRND > 0
134 #include <sys/rnd.h>
135 #endif
136 #ifndef PIPE_SOCKETPAIR
137 #include <sys/pipe.h>
138 #endif
139 #ifdef LKM
140 #include <sys/lkm.h>
141 #endif
142 #ifdef VERIFIED_EXEC
143 #include <sys/verified_exec.h>
144 #endif
145 #include <net80211/ieee80211_netbsd.h>
146 
147 #include <sys/syscall.h>
148 #include <sys/sa.h>
149 #include <sys/syscallargs.h>
150 
151 #include <ufs/ufs/quota.h>
152 
153 #include <miscfs/genfs/genfs.h>
154 #include <miscfs/syncfs/syncfs.h>
155 
156 #include <machine/cpu.h>
157 
158 #include <uvm/uvm.h>
159 
160 #include <dev/cons.h>
161 
162 #include <net/if.h>
163 #include <net/raw_cb.h>
164 
165 extern struct proc proc0;
166 extern struct lwp lwp0;
167 extern struct cwdinfo cwdi0;
168 
169 #ifndef curlwp
170 struct	lwp *curlwp = &lwp0;
171 #endif
172 struct	proc *initproc;
173 
174 struct	vnode *rootvp, *swapdev_vp;
175 int	boothowto;
176 int	cold = 1;			/* still working on startup */
177 struct	timeval boottime;
178 time_t	rootfstime;			/* recorded root fs time, if known */
179 
180 volatile int start_init_exec;		/* semaphore for start_init() */
181 
182 static void check_console(struct lwp *l);
183 static void start_init(void *);
184 void main(void);
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 void
193 main(void)
194 {
195 	struct lwp *l;
196 	struct proc *p;
197 	struct pdevinit *pdev;
198 	int s, error;
199 	extern struct pdevinit pdevinit[];
200 	extern void schedcpu(void *);
201 #ifdef NVNODE_IMPLICIT
202 	int usevnodes;
203 #endif
204 
205 	/*
206 	 * Initialize the current LWP pointer (curlwp) before
207 	 * any possible traps/probes to simplify trap processing.
208 	 */
209 	l = &lwp0;
210 	curlwp = l;
211 	l->l_cpu = curcpu();
212 	l->l_proc = &proc0;
213 	l->l_lid = 1;
214 
215 	/*
216 	 * Attempt to find console and initialize
217 	 * in case of early panic or other messages.
218 	 */
219 	consinit();
220 
221 	KERNEL_LOCK_INIT();
222 
223 	uvm_init();
224 
225 	/* Do machine-dependent initialization. */
226 	cpu_startup();
227 
228 	/* Initialize callouts. */
229 	callout_startup();
230 
231 	/* Initialize the buffer cache */
232 	bufinit();
233 
234 	/*
235 	 * Initialize mbuf's.  Do this now because we might attempt to
236 	 * allocate mbufs or mbuf clusters during autoconfiguration.
237 	 */
238 	mbinit();
239 
240 	/* Initialize sockets. */
241 	soinit();
242 
243 #ifdef KCONT
244 	/* Initialize kcont. */
245         kcont_init();
246 #endif
247 
248 	/*
249 	 * The following things must be done before autoconfiguration.
250 	 */
251 	evcnt_init();		/* initialize event counters */
252 #if NRND > 0
253 	rnd_init();		/* initialize RNG */
254 #endif
255 	/* Initialize the sysctl subsystem. */
256 	sysctl_init();
257 
258 	/* Initialize process and pgrp structures. */
259 	procinit();
260 
261 	/* Initialize signal-related data structures. */
262 	signal_init();
263 
264 	/* Create process 0 (the swapper). */
265 	proc0_init();
266 
267 	/*
268 	 * Charge root for one process.
269 	 */
270 	(void)chgproccnt(0, 1);
271 
272 	rqinit();
273 
274 	/* Initialize the file systems. */
275 #ifdef NVNODE_IMPLICIT
276 	/*
277 	 * If maximum number of vnodes in namei vnode cache is not explicitly
278 	 * defined in kernel config, adjust the number such as we use roughly
279 	 * 1.0% of memory for vnode cache (but not less than NVNODE vnodes).
280 	 */
281 	usevnodes = (ptoa((unsigned)physmem) / 100) / sizeof(struct vnode);
282 	if (usevnodes > desiredvnodes)
283 		desiredvnodes = usevnodes;
284 #endif
285 	vfsinit();
286 
287 	/* Configure the system hardware.  This will enable interrupts. */
288 	configure();
289 
290 	ubc_init();		/* must be after autoconfig */
291 
292 	/* Lock the kernel on behalf of proc0. */
293 	KERNEL_PROC_LOCK(l);
294 
295 #ifdef SYSVSHM
296 	/* Initialize System V style shared memory. */
297 	shminit();
298 #endif
299 
300 #ifdef SYSVSEM
301 	/* Initialize System V style semaphores. */
302 	seminit();
303 #endif
304 
305 #ifdef SYSVMSG
306 	/* Initialize System V style message queues. */
307 	msginit();
308 #endif
309 
310 #ifdef P1003_1B_SEMAPHORE
311 	/* Initialize posix semaphores */
312 	ksem_init();
313 #endif
314 
315 #ifdef VERIFIED_EXEC
316 	  /*
317 	   * Initialise the fingerprint operations vectors before
318 	   * fingerprints can be loaded.
319 	   */
320 	veriexec_init_fp_ops();
321 #endif
322 
323 	/* Attach pseudo-devices. */
324 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
325 		(*pdev->pdev_attach)(pdev->pdev_count);
326 
327 #ifdef	FAST_IPSEC
328 	/* Attach network crypto subsystem */
329 	ipsec_attach();
330 #endif
331 
332 	/*
333 	 * Initialize protocols.  Block reception of incoming packets
334 	 * until everything is ready.
335 	 */
336 	s = splnet();
337 	ifinit();
338 	domaininit();
339 	if_attachdomain();
340 	splx(s);
341 
342 #ifdef GPROF
343 	/* Initialize kernel profiling. */
344 	kmstartup();
345 #endif
346 
347 	/* Initialize system accouting. */
348 	acct_init();
349 
350 	/* Kick off timeout driven events by calling first time. */
351 	schedcpu(NULL);
352 
353 	/*
354 	 * Create process 1 (init(8)).  We do this now, as Unix has
355 	 * historically had init be process 1, and changing this would
356 	 * probably upset a lot of people.
357 	 *
358 	 * Note that process 1 won't immediately exec init(8), but will
359 	 * wait for us to inform it that the root file system has been
360 	 * mounted.
361 	 */
362 	if (fork1(l, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL, &initproc))
363 		panic("fork init");
364 
365 	/*
366 	 * Create any kernel threads who's creation was deferred because
367 	 * initproc had not yet been created.
368 	 */
369 	kthread_run_deferred_queue();
370 
371 	/*
372 	 * Now that device driver threads have been created, wait for
373 	 * them to finish any deferred autoconfiguration.  Note we don't
374 	 * need to lock this semaphore, since we haven't booted any
375 	 * secondary processors, yet.
376 	 */
377 	while (config_pending)
378 		(void) tsleep(&config_pending, PWAIT, "cfpend", 0);
379 
380 	/*
381 	 * Finalize configuration now that all real devices have been
382 	 * found.  This needs to be done before the root device is
383 	 * selected, since finalization may create the root device.
384 	 */
385 	config_finalize();
386 
387 	/*
388 	 * Now that autoconfiguration has completed, we can determine
389 	 * the root and dump devices.
390 	 */
391 	cpu_rootconf();
392 	cpu_dumpconf();
393 
394 	/* Mount the root file system. */
395 	do {
396 		domountroothook();
397 		if ((error = vfs_mountroot())) {
398 			printf("cannot mount root, error = %d\n", error);
399 			boothowto |= RB_ASKNAME;
400 			setroot(root_device,
401 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
402 		}
403 	} while (error != 0);
404 	mountroothook_destroy();
405 
406 	/*
407 	 * Initialise the time-of-day clock, passing the time recorded
408 	 * in the root filesystem (if any) for use by systems that
409 	 * don't have a non-volatile time-of-day device.
410 	 */
411 	inittodr(rootfstime);
412 
413 	CIRCLEQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
414 	CIRCLEQ_FIRST(&mountlist)->mnt_op->vfs_refcount++;
415 
416 	/*
417 	 * Get the vnode for '/'.  Set filedesc0.fd_fd.fd_cdir to
418 	 * reference it.
419 	 */
420 	error = VFS_ROOT(CIRCLEQ_FIRST(&mountlist), &rootvnode);
421 	if (error)
422 		panic("cannot find root vnode, error=%d", error);
423 	cwdi0.cwdi_cdir = rootvnode;
424 	VREF(cwdi0.cwdi_cdir);
425 	VOP_UNLOCK(rootvnode, 0);
426 	cwdi0.cwdi_rdir = NULL;
427 
428 	/*
429 	 * Now that root is mounted, we can fixup initproc's CWD
430 	 * info.  All other processes are kthreads, which merely
431 	 * share proc0's CWD info.
432 	 */
433 	initproc->p_cwdi->cwdi_cdir = rootvnode;
434 	VREF(initproc->p_cwdi->cwdi_cdir);
435 	initproc->p_cwdi->cwdi_rdir = NULL;
436 
437 	/*
438 	 * Now can look at time, having had a chance to verify the time
439 	 * from the file system.  Reset p->p_rtime as it may have been
440 	 * munched in mi_switch() after the time got set.
441 	 */
442 	proclist_lock_read();
443 	s = splsched();
444 	LIST_FOREACH(p, &allproc, p_list) {
445 		KASSERT((p->p_flag & P_MARKER) == 0);
446 		p->p_stats->p_start = mono_time = boottime = time;
447 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
448 			if (l->l_cpu != NULL)
449 				l->l_cpu->ci_schedstate.spc_runtime = time;
450 		}
451 		p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
452 	}
453 	splx(s);
454 	proclist_unlock_read();
455 
456 	/* Create the pageout daemon kernel thread. */
457 	uvm_swap_init();
458 	if (kthread_create1(uvm_pageout, NULL, NULL, "pagedaemon"))
459 		panic("fork pagedaemon");
460 
461 	/* Create the filesystem syncer kernel thread. */
462 	if (kthread_create1(sched_sync, NULL, NULL, "ioflush"))
463 		panic("fork syncer");
464 
465 	/* Create the aiodone daemon kernel thread. */
466 	if (kthread_create1(uvm_aiodone_daemon, NULL, &uvm.aiodoned_proc,
467 	    "aiodoned"))
468 		panic("fork aiodoned");
469 
470 #if defined(MULTIPROCESSOR)
471 	/* Boot the secondary processors. */
472 	cpu_boot_secondary_processors();
473 #endif
474 
475 	/* Initialize exec structures */
476 	exec_init(1);
477 
478 	/*
479 	 * Okay, now we can let init(8) exec!  It's off to userland!
480 	 */
481 	start_init_exec = 1;
482 	wakeup(&start_init_exec);
483 
484 	/* The scheduler is an infinite loop. */
485 	uvm_scheduler();
486 	/* NOTREACHED */
487 }
488 
489 void
490 setrootfstime(time_t t)
491 {
492 
493 	rootfstime = t;
494 }
495 
496 static void
497 check_console(struct lwp *l)
498 {
499 	struct nameidata nd;
500 	int error;
501 
502 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", l);
503 	error = namei(&nd);
504 	if (error == 0)
505 		vrele(nd.ni_vp);
506 	else if (error == ENOENT)
507 		printf("warning: no /dev/console\n");
508 	else
509 		printf("warning: lookup /dev/console: error %d\n", error);
510 }
511 
512 /*
513  * List of paths to try when searching for "init".
514  */
515 static const char *initpaths[] = {
516 	"/sbin/init",
517 	"/sbin/oinit",
518 	"/sbin/init.bak",
519 	NULL,
520 };
521 
522 /*
523  * Start the initial user process; try exec'ing each pathname in "initpaths".
524  * The program is invoked with one argument containing the boot flags.
525  */
526 static void
527 start_init(void *arg)
528 {
529 	struct lwp *l = arg;
530 	struct proc *p = l->l_proc;
531 	vaddr_t addr;
532 	struct sys_execve_args /* {
533 		syscallarg(const char *) path;
534 		syscallarg(char * const *) argp;
535 		syscallarg(char * const *) envp;
536 	} */ args;
537 	int options, i, error;
538 	register_t retval[2];
539 	char flags[4], *flagsp;
540 	const char *path, *slash;
541 	char *ucp, **uap, *arg0, *arg1 = NULL;
542 	char ipath[129];
543 	int ipx, len;
544 
545 	/*
546 	 * Now in process 1.
547 	 */
548 	strncpy(p->p_comm, "init", MAXCOMLEN);
549 
550 	/*
551 	 * Wait for main() to tell us that it's safe to exec.
552 	 */
553 	while (start_init_exec == 0)
554 		(void) tsleep(&start_init_exec, PWAIT, "initexec", 0);
555 
556 	/*
557 	 * This is not the right way to do this.  We really should
558 	 * hand-craft a descriptor onto /dev/console to hand to init,
559 	 * but that's a _lot_ more work, and the benefit from this easy
560 	 * hack makes up for the "good is the enemy of the best" effect.
561 	 */
562 	check_console(l);
563 
564 	/*
565 	 * Need just enough stack to hold the faked-up "execve()" arguments.
566 	 */
567 	addr = (vaddr_t)STACK_ALLOC(USRSTACK, PAGE_SIZE);
568 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
569                     NULL, UVM_UNKNOWN_OFFSET, 0,
570                     UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
571 		    UVM_ADV_NORMAL,
572                     UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)) != 0)
573 		panic("init: couldn't allocate argument space");
574 	p->p_vmspace->vm_maxsaddr = (caddr_t)STACK_MAX(addr, PAGE_SIZE);
575 
576 	ipx = 0;
577 	while (1) {
578 		if (boothowto & RB_ASKNAME) {
579 			printf("init path");
580 			if (initpaths[ipx])
581 				printf(" (default %s)", initpaths[ipx]);
582 			printf(": ");
583 			len = cngetsn(ipath, sizeof(ipath)-1);
584 			if (len == 0) {
585 				if (initpaths[ipx])
586 					path = initpaths[ipx++];
587 				else
588 					continue;
589 			} else {
590 				ipath[len] = '\0';
591 				path = ipath;
592 			}
593 		} else {
594 			if ((path = initpaths[ipx++]) == NULL)
595 				break;
596 		}
597 
598 		ucp = (char *)USRSTACK;
599 
600 		/*
601 		 * Construct the boot flag argument.
602 		 */
603 		flagsp = flags;
604 		*flagsp++ = '-';
605 		options = 0;
606 
607 		if (boothowto & RB_SINGLE) {
608 			*flagsp++ = 's';
609 			options = 1;
610 		}
611 #ifdef notyet
612 		if (boothowto & RB_FASTBOOT) {
613 			*flagsp++ = 'f';
614 			options = 1;
615 		}
616 #endif
617 
618 		/*
619 		 * Move out the flags (arg 1), if necessary.
620 		 */
621 		if (options != 0) {
622 			*flagsp++ = '\0';
623 			i = flagsp - flags;
624 #ifdef DEBUG
625 			printf("init: copying out flags `%s' %d\n", flags, i);
626 #endif
627 			arg1 = STACK_ALLOC(ucp, i);
628 			ucp = STACK_MAX(arg1, i);
629 			(void)copyout((caddr_t)flags, arg1, i);
630 		}
631 
632 		/*
633 		 * Move out the file name (also arg 0).
634 		 */
635 		i = strlen(path) + 1;
636 #ifdef DEBUG
637 		printf("init: copying out path `%s' %d\n", path, i);
638 #else
639 		if (boothowto & RB_ASKNAME || path != initpaths[0])
640 			printf("init: trying %s\n", path);
641 #endif
642 		arg0 = STACK_ALLOC(ucp, i);
643 		ucp = STACK_MAX(arg0, i);
644 		(void)copyout(path, arg0, i);
645 
646 		/*
647 		 * Move out the arg pointers.
648 		 */
649 		ucp = (caddr_t)STACK_ALIGN(ucp, ALIGNBYTES);
650 		uap = (char **)STACK_ALLOC(ucp, sizeof(char *) * 3);
651 		SCARG(&args, path) = arg0;
652 		SCARG(&args, argp) = uap;
653 		SCARG(&args, envp) = NULL;
654 		slash = strrchr(path, '/');
655 		if (slash)
656 			(void)suword((caddr_t)uap++,
657 			    (long)arg0 + (slash + 1 - path));
658 		else
659 			(void)suword((caddr_t)uap++, (long)arg0);
660 		if (options != 0)
661 			(void)suword((caddr_t)uap++, (long)arg1);
662 		(void)suword((caddr_t)uap++, 0);	/* terminator */
663 
664 		/*
665 		 * Now try to exec the program.  If can't for any reason
666 		 * other than it doesn't exist, complain.
667 		 */
668 		error = sys_execve(l, &args, retval);
669 		if (error == 0 || error == EJUSTRETURN) {
670 			KERNEL_PROC_UNLOCK(l);
671 			return;
672 		}
673 		printf("exec %s: error %d\n", path, error);
674 	}
675 	printf("init: not found\n");
676 	panic("no init");
677 }
678