xref: /netbsd-src/sys/kern/init_main.c (revision c71562d660be5e4ad22016bce45e96f08af190cc)
1 /*	$NetBSD: init_main.c,v 1.265 2006/04/10 11:16:22 onoe 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 1.265 2006/04/10 11:16:22 onoe Exp $");
75 
76 #include "opt_ipsec.h"
77 #include "opt_sysv.h"
78 #include "opt_multiprocessor.h"
79 #include "opt_pipe.h"
80 #include "opt_syscall_debug.h"
81 #include "opt_posix.h"
82 #include "opt_kcont.h"
83 #include "opt_verified_exec.h"
84 
85 #include "rnd.h"
86 
87 #include <sys/param.h>
88 #include <sys/acct.h>
89 #include <sys/filedesc.h>
90 #include <sys/file.h>
91 #include <sys/errno.h>
92 #include <sys/callout.h>
93 #include <sys/kernel.h>
94 #include <sys/kcont.h>
95 #include <sys/mount.h>
96 #include <sys/proc.h>
97 #include <sys/kthread.h>
98 #include <sys/resourcevar.h>
99 #include <sys/signalvar.h>
100 #include <sys/systm.h>
101 #include <sys/vnode.h>
102 #include <sys/tty.h>
103 #include <sys/conf.h>
104 #include <sys/disklabel.h>
105 #include <sys/buf.h>
106 #include <sys/device.h>
107 #include <sys/exec.h>
108 #include <sys/socketvar.h>
109 #include <sys/protosw.h>
110 #include <sys/reboot.h>
111 #include <sys/user.h>
112 #include <sys/sysctl.h>
113 #include <sys/event.h>
114 #include <sys/mbuf.h>
115 #ifdef FAST_IPSEC
116 #include <netipsec/ipsec.h>
117 #endif
118 #ifdef SYSVSHM
119 #include <sys/shm.h>
120 #endif
121 #ifdef SYSVSEM
122 #include <sys/sem.h>
123 #endif
124 #ifdef SYSVMSG
125 #include <sys/msg.h>
126 #endif
127 #ifdef P1003_1B_SEMAPHORE
128 #include <sys/ksem.h>
129 #endif
130 #include <sys/domain.h>
131 #include <sys/namei.h>
132 #if NRND > 0
133 #include <sys/rnd.h>
134 #endif
135 #ifndef PIPE_SOCKETPAIR
136 #include <sys/pipe.h>
137 #endif
138 #ifdef LKM
139 #include <sys/lkm.h>
140 #endif
141 #ifdef VERIFIED_EXEC
142 #include <sys/verified_exec.h>
143 #endif
144 #include <net80211/ieee80211_netbsd.h>
145 
146 #include <sys/syscall.h>
147 #include <sys/sa.h>
148 #include <sys/syscallargs.h>
149 
150 #include <ufs/ufs/quota.h>
151 
152 #include <miscfs/genfs/genfs.h>
153 #include <miscfs/syncfs/syncfs.h>
154 
155 #include <machine/cpu.h>
156 
157 #include <uvm/uvm.h>
158 
159 #include <dev/cons.h>
160 
161 #include <net/if.h>
162 #include <net/raw_cb.h>
163 
164 extern struct proc proc0;
165 extern struct lwp lwp0;
166 extern struct cwdinfo cwdi0;
167 
168 #ifndef curlwp
169 struct	lwp *curlwp = &lwp0;
170 #endif
171 struct	proc *initproc;
172 
173 struct	vnode *rootvp, *swapdev_vp;
174 int	boothowto;
175 int	cold = 1;			/* still working on startup */
176 struct	timeval boottime;
177 time_t	rootfstime;			/* recorded root fs time, if known */
178 
179 volatile int start_init_exec;		/* semaphore for start_init() */
180 
181 static void check_console(struct lwp *l);
182 static void start_init(void *);
183 void main(void);
184 
185 /*
186  * System startup; initialize the world, create process 0, mount root
187  * filesystem, and fork to create init and pagedaemon.  Most of the
188  * hard work is done in the lower-level initialization routines including
189  * startup(), which does memory initialization and autoconfiguration.
190  */
191 void
192 main(void)
193 {
194 	struct lwp *l;
195 	struct proc *p;
196 	struct pdevinit *pdev;
197 	int s, error;
198 	extern struct pdevinit pdevinit[];
199 	extern void schedcpu(void *);
200 #ifdef NVNODE_IMPLICIT
201 	int usevnodes;
202 #endif
203 
204 	/*
205 	 * Initialize the current LWP pointer (curlwp) before
206 	 * any possible traps/probes to simplify trap processing.
207 	 */
208 	l = &lwp0;
209 	curlwp = l;
210 	l->l_cpu = curcpu();
211 	l->l_proc = &proc0;
212 	l->l_lid = 1;
213 
214 	/*
215 	 * Attempt to find console and initialize
216 	 * in case of early panic or other messages.
217 	 */
218 	consinit();
219 
220 	KERNEL_LOCK_INIT();
221 
222 	uvm_init();
223 
224 	/* Do machine-dependent initialization. */
225 	cpu_startup();
226 
227 	/* Initialize callouts. */
228 	callout_startup();
229 
230 	/* Initialize the buffer cache */
231 	bufinit();
232 
233 	/*
234 	 * Initialize mbuf's.  Do this now because we might attempt to
235 	 * allocate mbufs or mbuf clusters during autoconfiguration.
236 	 */
237 	mbinit();
238 
239 	/* Initialize sockets. */
240 	soinit();
241 
242 #ifdef KCONT
243 	/* Initialize kcont. */
244         kcont_init();
245 #endif
246 
247 	/*
248 	 * The following things must be done before autoconfiguration.
249 	 */
250 	evcnt_init();		/* initialize event counters */
251 #if NRND > 0
252 	rnd_init();		/* initialize RNG */
253 #endif
254 	/* Initialize the sysctl subsystem. */
255 	sysctl_init();
256 
257 	/* Initialize process and pgrp structures. */
258 	procinit();
259 
260 	/* Initialize signal-related data structures. */
261 	signal_init();
262 
263 	/* Create process 0 (the swapper). */
264 	proc0_init();
265 
266 	/*
267 	 * Charge root for one process.
268 	 */
269 	(void)chgproccnt(0, 1);
270 
271 	rqinit();
272 
273 	/* Initialize the file systems. */
274 #ifdef NVNODE_IMPLICIT
275 	/*
276 	 * If maximum number of vnodes in namei vnode cache is not explicitly
277 	 * defined in kernel config, adjust the number such as we use roughly
278 	 * 1.0% of memory for vnode cache (but not less than NVNODE vnodes).
279 	 */
280 	usevnodes = (ptoa((unsigned)physmem) / 100) / sizeof(struct vnode);
281 	if (usevnodes > desiredvnodes)
282 		desiredvnodes = usevnodes;
283 #endif
284 	vfsinit();
285 
286 	/* Configure the system hardware.  This will enable interrupts. */
287 	configure();
288 
289 	ubc_init();		/* must be after autoconfig */
290 
291 	/* Lock the kernel on behalf of proc0. */
292 	KERNEL_PROC_LOCK(l);
293 
294 #ifdef SYSVSHM
295 	/* Initialize System V style shared memory. */
296 	shminit();
297 #endif
298 
299 #ifdef SYSVSEM
300 	/* Initialize System V style semaphores. */
301 	seminit();
302 #endif
303 
304 #ifdef SYSVMSG
305 	/* Initialize System V style message queues. */
306 	msginit();
307 #endif
308 
309 #ifdef P1003_1B_SEMAPHORE
310 	/* Initialize posix semaphores */
311 	ksem_init();
312 #endif
313 
314 #ifdef VERIFIED_EXEC
315 	  /*
316 	   * Initialise the fingerprint operations vectors before
317 	   * fingerprints can be loaded.
318 	   */
319 	veriexec_init_fp_ops();
320 #endif
321 
322 	/* Attach pseudo-devices. */
323 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
324 		(*pdev->pdev_attach)(pdev->pdev_count);
325 
326 #ifdef	FAST_IPSEC
327 	/* Attach network crypto subsystem */
328 	ipsec_attach();
329 #endif
330 
331 	/*
332 	 * Initialize protocols.  Block reception of incoming packets
333 	 * until everything is ready.
334 	 */
335 	s = splnet();
336 	ifinit();
337 	domaininit();
338 	if_attachdomain();
339 	splx(s);
340 
341 #ifdef GPROF
342 	/* Initialize kernel profiling. */
343 	kmstartup();
344 #endif
345 
346 	/* Initialize system accouting. */
347 	acct_init();
348 
349 	/* Kick off timeout driven events by calling first time. */
350 	schedcpu(NULL);
351 
352 	/*
353 	 * Create process 1 (init(8)).  We do this now, as Unix has
354 	 * historically had init be process 1, and changing this would
355 	 * probably upset a lot of people.
356 	 *
357 	 * Note that process 1 won't immediately exec init(8), but will
358 	 * wait for us to inform it that the root file system has been
359 	 * mounted.
360 	 */
361 	if (fork1(l, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL, &initproc))
362 		panic("fork init");
363 
364 	/*
365 	 * Create any kernel threads who's creation was deferred because
366 	 * initproc had not yet been created.
367 	 */
368 	kthread_run_deferred_queue();
369 
370 	/*
371 	 * Now that device driver threads have been created, wait for
372 	 * them to finish any deferred autoconfiguration.  Note we don't
373 	 * need to lock this semaphore, since we haven't booted any
374 	 * secondary processors, yet.
375 	 */
376 	while (config_pending)
377 		(void) tsleep(&config_pending, PWAIT, "cfpend", 0);
378 
379 	/*
380 	 * Finalize configuration now that all real devices have been
381 	 * found.  This needs to be done before the root device is
382 	 * selected, since finalization may create the root device.
383 	 */
384 	config_finalize();
385 
386 	/*
387 	 * Now that autoconfiguration has completed, we can determine
388 	 * the root and dump devices.
389 	 */
390 	cpu_rootconf();
391 	cpu_dumpconf();
392 
393 	/* Mount the root file system. */
394 	do {
395 		domountroothook();
396 		if ((error = vfs_mountroot())) {
397 			printf("cannot mount root, error = %d\n", error);
398 			boothowto |= RB_ASKNAME;
399 			setroot(root_device,
400 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
401 		}
402 	} while (error != 0);
403 	mountroothook_destroy();
404 
405 	/*
406 	 * Initialise the time-of-day clock, passing the time recorded
407 	 * in the root filesystem (if any) for use by systems that
408 	 * don't have a non-volatile time-of-day device.
409 	 */
410 	inittodr(rootfstime);
411 
412 	CIRCLEQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
413 	CIRCLEQ_FIRST(&mountlist)->mnt_op->vfs_refcount++;
414 
415 	/*
416 	 * Get the vnode for '/'.  Set filedesc0.fd_fd.fd_cdir to
417 	 * reference it.
418 	 */
419 	error = VFS_ROOT(CIRCLEQ_FIRST(&mountlist), &rootvnode);
420 	if (error)
421 		panic("cannot find root vnode, error=%d", error);
422 	cwdi0.cwdi_cdir = rootvnode;
423 	VREF(cwdi0.cwdi_cdir);
424 	VOP_UNLOCK(rootvnode, 0);
425 	cwdi0.cwdi_rdir = NULL;
426 
427 	/*
428 	 * Now that root is mounted, we can fixup initproc's CWD
429 	 * info.  All other processes are kthreads, which merely
430 	 * share proc0's CWD info.
431 	 */
432 	initproc->p_cwdi->cwdi_cdir = rootvnode;
433 	VREF(initproc->p_cwdi->cwdi_cdir);
434 	initproc->p_cwdi->cwdi_rdir = NULL;
435 
436 	/*
437 	 * Now can look at time, having had a chance to verify the time
438 	 * from the file system.  Reset p->p_rtime as it may have been
439 	 * munched in mi_switch() after the time got set.
440 	 */
441 	proclist_lock_read();
442 	s = splsched();
443 	LIST_FOREACH(p, &allproc, p_list) {
444 		KASSERT((p->p_flag & P_MARKER) == 0);
445 		p->p_stats->p_start = mono_time = boottime = time;
446 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
447 			if (l->l_cpu != NULL)
448 				l->l_cpu->ci_schedstate.spc_runtime = time;
449 		}
450 		p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
451 	}
452 	splx(s);
453 	proclist_unlock_read();
454 
455 	/* Create the pageout daemon kernel thread. */
456 	uvm_swap_init();
457 	if (kthread_create1(uvm_pageout, NULL, NULL, "pagedaemon"))
458 		panic("fork pagedaemon");
459 
460 	/* Create the filesystem syncer kernel thread. */
461 	if (kthread_create1(sched_sync, NULL, NULL, "ioflush"))
462 		panic("fork syncer");
463 
464 	/* Create the aiodone daemon kernel thread. */
465 	if (kthread_create1(uvm_aiodone_daemon, NULL, &uvm.aiodoned_proc,
466 	    "aiodoned"))
467 		panic("fork aiodoned");
468 
469 #if defined(MULTIPROCESSOR)
470 	/* Boot the secondary processors. */
471 	cpu_boot_secondary_processors();
472 #endif
473 
474 	/* Initialize exec structures */
475 	exec_init(1);
476 
477 	/*
478 	 * Okay, now we can let init(8) exec!  It's off to userland!
479 	 */
480 	start_init_exec = 1;
481 	wakeup(&start_init_exec);
482 
483 	/* The scheduler is an infinite loop. */
484 	uvm_scheduler();
485 	/* NOTREACHED */
486 }
487 
488 void
489 setrootfstime(time_t t)
490 {
491 	rootfstime = t;
492 }
493 
494 static void
495 check_console(struct lwp *l)
496 {
497 	struct nameidata nd;
498 	int error;
499 
500 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", l);
501 	error = namei(&nd);
502 	if (error == 0)
503 		vrele(nd.ni_vp);
504 	else if (error == ENOENT)
505 		printf("warning: no /dev/console\n");
506 	else
507 		printf("warning: lookup /dev/console: error %d\n", error);
508 }
509 
510 /*
511  * List of paths to try when searching for "init".
512  */
513 static const char *initpaths[] = {
514 	"/sbin/init",
515 	"/sbin/oinit",
516 	"/sbin/init.bak",
517 	NULL,
518 };
519 
520 /*
521  * Start the initial user process; try exec'ing each pathname in "initpaths".
522  * The program is invoked with one argument containing the boot flags.
523  */
524 static void
525 start_init(void *arg)
526 {
527 	struct lwp *l = arg;
528 	struct proc *p = l->l_proc;
529 	vaddr_t addr;
530 	struct sys_execve_args /* {
531 		syscallarg(const char *) path;
532 		syscallarg(char * const *) argp;
533 		syscallarg(char * const *) envp;
534 	} */ args;
535 	int options, i, error;
536 	register_t retval[2];
537 	char flags[4], *flagsp;
538 	const char *path, *slash;
539 	char *ucp, **uap, *arg0, *arg1 = NULL;
540 	char ipath[129];
541 	int ipx, len;
542 
543 	/*
544 	 * Now in process 1.
545 	 */
546 	strncpy(p->p_comm, "init", MAXCOMLEN);
547 
548 	/*
549 	 * Wait for main() to tell us that it's safe to exec.
550 	 */
551 	while (start_init_exec == 0)
552 		(void) tsleep(&start_init_exec, PWAIT, "initexec", 0);
553 
554 	/*
555 	 * This is not the right way to do this.  We really should
556 	 * hand-craft a descriptor onto /dev/console to hand to init,
557 	 * but that's a _lot_ more work, and the benefit from this easy
558 	 * hack makes up for the "good is the enemy of the best" effect.
559 	 */
560 	check_console(l);
561 
562 	/*
563 	 * Need just enough stack to hold the faked-up "execve()" arguments.
564 	 */
565 	addr = (vaddr_t)STACK_ALLOC(USRSTACK, PAGE_SIZE);
566 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
567                     NULL, UVM_UNKNOWN_OFFSET, 0,
568                     UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
569 		    UVM_ADV_NORMAL,
570                     UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)) != 0)
571 		panic("init: couldn't allocate argument space");
572 	p->p_vmspace->vm_maxsaddr = (caddr_t)STACK_MAX(addr, PAGE_SIZE);
573 
574 	ipx = 0;
575 	while (1) {
576 		if (boothowto & RB_ASKNAME) {
577 			printf("init path");
578 			if (initpaths[ipx])
579 				printf(" (default %s)", initpaths[ipx]);
580 			printf(": ");
581 			len = cngetsn(ipath, sizeof(ipath)-1);
582 			if (len == 0) {
583 				if (initpaths[ipx])
584 					path = initpaths[ipx++];
585 				else
586 					continue;
587 			} else {
588 				ipath[len] = '\0';
589 				path = ipath;
590 			}
591 		} else {
592 			if ((path = initpaths[ipx++]) == NULL)
593 				break;
594 		}
595 
596 		ucp = (char *)USRSTACK;
597 
598 		/*
599 		 * Construct the boot flag argument.
600 		 */
601 		flagsp = flags;
602 		*flagsp++ = '-';
603 		options = 0;
604 
605 		if (boothowto & RB_SINGLE) {
606 			*flagsp++ = 's';
607 			options = 1;
608 		}
609 #ifdef notyet
610 		if (boothowto & RB_FASTBOOT) {
611 			*flagsp++ = 'f';
612 			options = 1;
613 		}
614 #endif
615 
616 		/*
617 		 * Move out the flags (arg 1), if necessary.
618 		 */
619 		if (options != 0) {
620 			*flagsp++ = '\0';
621 			i = flagsp - flags;
622 #ifdef DEBUG
623 			printf("init: copying out flags `%s' %d\n", flags, i);
624 #endif
625 			arg1 = STACK_ALLOC(ucp, i);
626 			ucp = STACK_MAX(arg1, i);
627 			(void)copyout((caddr_t)flags, arg1, i);
628 		}
629 
630 		/*
631 		 * Move out the file name (also arg 0).
632 		 */
633 		i = strlen(path) + 1;
634 #ifdef DEBUG
635 		printf("init: copying out path `%s' %d\n", path, i);
636 #else
637 		if (boothowto & RB_ASKNAME || path != initpaths[0])
638 			printf("init: trying %s\n", path);
639 #endif
640 		arg0 = STACK_ALLOC(ucp, i);
641 		ucp = STACK_MAX(arg0, i);
642 		(void)copyout(path, arg0, i);
643 
644 		/*
645 		 * Move out the arg pointers.
646 		 */
647 		ucp = (caddr_t)STACK_ALIGN(ucp, ALIGNBYTES);
648 		uap = (char **)STACK_ALLOC(ucp, sizeof(char *) * 3);
649 		SCARG(&args, path) = arg0;
650 		SCARG(&args, argp) = uap;
651 		SCARG(&args, envp) = NULL;
652 		slash = strrchr(path, '/');
653 		if (slash)
654 			(void)suword((caddr_t)uap++,
655 			    (long)arg0 + (slash + 1 - path));
656 		else
657 			(void)suword((caddr_t)uap++, (long)arg0);
658 		if (options != 0)
659 			(void)suword((caddr_t)uap++, (long)arg1);
660 		(void)suword((caddr_t)uap++, 0);	/* terminator */
661 
662 		/*
663 		 * Now try to exec the program.  If can't for any reason
664 		 * other than it doesn't exist, complain.
665 		 */
666 		error = sys_execve(l, &args, retval);
667 		if (error == 0 || error == EJUSTRETURN) {
668 			KERNEL_PROC_UNLOCK(l);
669 			return;
670 		}
671 		printf("exec %s: error %d\n", path, error);
672 	}
673 	printf("init: not found\n");
674 	panic("no init");
675 }
676