xref: /netbsd-src/sys/kern/init_main.c (revision 0920b4f20b78ab1ccd9f2312fbe10deaf000cbf3)
1 /*	$NetBSD: init_main.c,v 1.312 2007/08/04 11:03:00 ad 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 1.312 2007/08/04 11:03:00 ad Exp $");
75 
76 #include "opt_ipsec.h"
77 #include "opt_multiprocessor.h"
78 #include "opt_ntp.h"
79 #include "opt_pipe.h"
80 #include "opt_posix.h"
81 #include "opt_syscall_debug.h"
82 #include "opt_sysv.h"
83 #include "opt_systrace.h"
84 #include "opt_fileassoc.h"
85 #include "opt_ktrace.h"
86 #include "opt_pax.h"
87 
88 #include "sysmon_taskq.h"
89 #include "rnd.h"
90 #include "sysmon_envsys.h"
91 #include "sysmon_power.h"
92 #include "veriexec.h"
93 
94 #include <sys/param.h>
95 #include <sys/acct.h>
96 #include <sys/filedesc.h>
97 #include <sys/file.h>
98 #include <sys/errno.h>
99 #include <sys/callout.h>
100 #include <sys/cpu.h>
101 #include <sys/kernel.h>
102 #include <sys/kmem.h>
103 #include <sys/mount.h>
104 #include <sys/proc.h>
105 #include <sys/kthread.h>
106 #include <sys/resourcevar.h>
107 #include <sys/signalvar.h>
108 #include <sys/systm.h>
109 #include <sys/vnode.h>
110 #include <sys/fstrans.h>
111 #include <sys/tty.h>
112 #include <sys/conf.h>
113 #include <sys/disklabel.h>
114 #include <sys/buf.h>
115 #include <sys/device.h>
116 #include <sys/exec.h>
117 #include <sys/socketvar.h>
118 #include <sys/protosw.h>
119 #include <sys/reboot.h>
120 #include <sys/user.h>
121 #include <sys/sysctl.h>
122 #include <sys/event.h>
123 #include <sys/mbuf.h>
124 #include <sys/sched.h>
125 #include <sys/sleepq.h>
126 #include <sys/iostat.h>
127 #include <sys/vmem.h>
128 #include <sys/uuid.h>
129 #include <sys/extent.h>
130 #include <sys/disk.h>
131 #ifdef FAST_IPSEC
132 #include <netipsec/ipsec.h>
133 #endif
134 #ifdef SYSVSHM
135 #include <sys/shm.h>
136 #endif
137 #ifdef SYSVSEM
138 #include <sys/sem.h>
139 #endif
140 #ifdef SYSVMSG
141 #include <sys/msg.h>
142 #endif
143 #ifdef SYSTRACE
144 #include <sys/systrace.h>
145 #endif
146 #ifdef P1003_1B_SEMAPHORE
147 #include <sys/ksem.h>
148 #endif
149 #include <sys/domain.h>
150 #include <sys/namei.h>
151 #if NRND > 0
152 #include <sys/rnd.h>
153 #endif
154 #include <sys/pipe.h>
155 #ifdef LKM
156 #include <sys/lkm.h>
157 #endif
158 #if NVERIEXEC > 0
159 #include <sys/verified_exec.h>
160 #endif /* NVERIEXEC > 0 */
161 #ifdef KTRACE
162 #include <sys/ktrace.h>
163 #endif
164 #include <sys/debug.h>
165 #include <sys/kauth.h>
166 #include <net80211/ieee80211_netbsd.h>
167 
168 #include <sys/syscall.h>
169 #include <sys/syscallargs.h>
170 
171 #if defined(PAX_MPROTECT) || defined(PAX_SEGVGUARD)
172 #include <sys/pax.h>
173 #endif /* PAX_MPROTECT || PAX_SEGVGUARD */
174 #include <ufs/ufs/quota.h>
175 
176 #include <miscfs/genfs/genfs.h>
177 #include <miscfs/syncfs/syncfs.h>
178 
179 #include <machine/cpu.h>
180 
181 #include <uvm/uvm.h>
182 
183 #if NSYSMON_TASKQ > 0
184 #include <dev/sysmon/sysmon_taskq.h>
185 #endif
186 
187 #include <dev/cons.h>
188 
189 #if NSYSMON_ENVSYS > 0 || NSYSMON_POWER > 0
190 #include <dev/sysmon/sysmonvar.h>
191 #endif
192 
193 #include <net/if.h>
194 #include <net/raw_cb.h>
195 
196 #include <secmodel/secmodel.h>
197 
198 extern struct proc proc0;
199 extern struct lwp lwp0;
200 extern struct cwdinfo cwdi0;
201 extern time_t rootfstime;
202 
203 #ifndef curlwp
204 struct	lwp *curlwp = &lwp0;
205 #endif
206 struct	proc *initproc;
207 
208 struct	vnode *rootvp, *swapdev_vp;
209 int	boothowto;
210 int	cold = 1;			/* still working on startup */
211 struct timeval boottime;	        /* time at system startup - will only follow settime deltas */
212 int	ncpu = 0;			/* number of CPUs configured, assume 1 */
213 
214 volatile int start_init_exec;		/* semaphore for start_init() */
215 
216 static void check_console(struct lwp *l);
217 static void start_init(void *);
218 void main(void);
219 
220 #if defined(__SSP__) || defined(__SSP_ALL__)
221 long __stack_chk_guard[8] = {0, 0, 0, 0, 0, 0, 0, 0};
222 void __stack_chk_fail(void);
223 
224 void
225 __stack_chk_fail(void)
226 {
227 	panic("stack overflow detected; terminated");
228 }
229 #endif
230 
231 void __secmodel_none(void);
232 __weak_alias(secmodel_start,__secmodel_none);
233 void
234 __secmodel_none(void)
235 {
236 	return;
237 }
238 
239 /*
240  * System startup; initialize the world, create process 0, mount root
241  * filesystem, and fork to create init and pagedaemon.  Most of the
242  * hard work is done in the lower-level initialization routines including
243  * startup(), which does memory initialization and autoconfiguration.
244  */
245 void
246 main(void)
247 {
248 #ifdef __HAVE_TIMECOUNTER
249 	struct timeval time;
250 #endif
251 	struct lwp *l;
252 	struct proc *p;
253 	struct pdevinit *pdev;
254 	int s, error;
255 	extern struct pdevinit pdevinit[];
256 #ifdef NVNODE_IMPLICIT
257 	int usevnodes;
258 #endif
259 	CPU_INFO_ITERATOR cii;
260 	struct cpu_info *ci;
261 
262 	/*
263 	 * Initialize the current LWP pointer (curlwp) before
264 	 * any possible traps/probes to simplify trap processing.
265 	 */
266 	l = &lwp0;
267 	curlwp = l;
268 	l->l_cpu = curcpu();
269 	l->l_proc = &proc0;
270 	l->l_lid = 1;
271 
272 	/*
273 	 * Attempt to find console and initialize
274 	 * in case of early panic or other messages.
275 	 */
276 	consinit();
277 
278 	KERNEL_LOCK_INIT();
279 
280 	uvm_init();
281 
282 #ifdef DEBUG
283 	debug_init();
284 #endif
285 
286 	kmem_init();
287 
288 	/* Initialize the extent manager. */
289 	extent_init();
290 
291 	/* Do machine-dependent initialization. */
292 	cpu_startup();
293 
294 	/* Initialize callouts, part 1. */
295 	callout_startup();
296 
297 	/*
298 	 * Initialize the kernel authorization subsystem and start the
299 	 * default security model, if any. We need to do this early
300 	 * enough so that subsystems relying on any of the aforementioned
301 	 * can work properly. Since the security model may dictate the
302 	 * credential inheritance policy, it is needed at least before
303 	 * any process is created, specifically proc0.
304 	 */
305 	kauth_init();
306 	secmodel_start();
307 
308 	/* Initialize the buffer cache */
309 	bufinit();
310 
311 	/*
312 	 * Initialize mbuf's.  Do this now because we might attempt to
313 	 * allocate mbufs or mbuf clusters during autoconfiguration.
314 	 */
315 	mbinit();
316 
317 	/* Initialize sockets. */
318 	soinit();
319 
320 	/*
321 	 * The following things must be done before autoconfiguration.
322 	 */
323 	evcnt_init();		/* initialize event counters */
324 #if NRND > 0
325 	rnd_init();		/* initialize RNG */
326 #endif
327 
328 	/* Initialize process and pgrp structures. */
329 	procinit();
330 	lwpinit();
331 
332 	/* Initialize signal-related data structures. */
333 	signal_init();
334 
335 	/* Create process 0 (the swapper). */
336 	proc0_init();
337 
338 	/* Initialize the UID hash table. */
339 	uid_init();
340 
341 	/* Charge root for one process. */
342 	(void)chgproccnt(0, 1);
343 
344 	/* Initialize the run queues, turnstiles and sleep queues. */
345 	mutex_init(&cpu_lock, MUTEX_DEFAULT, IPL_NONE);
346 	sched_rqinit();
347 	turnstile_init();
348 	sleeptab_init(&sleeptab);
349 
350 	/* MI initialization of the boot cpu */
351 	error = mi_cpu_attach(curcpu());
352 	KASSERT(error == 0);
353 
354 	/* Initialize the sysctl subsystem. */
355 	sysctl_init();
356 
357 	/* Initialize I/O statistics. */
358 	iostat_init();
359 
360 	/* Initialize the file systems. */
361 #ifdef NVNODE_IMPLICIT
362 	/*
363 	 * If maximum number of vnodes in namei vnode cache is not explicitly
364 	 * defined in kernel config, adjust the number such as we use roughly
365 	 * 1.0% of memory for vnode cache (but not less than NVNODE vnodes).
366 	 */
367 	usevnodes = (ptoa((unsigned)physmem) / 100) / sizeof(struct vnode);
368 	if (usevnodes > desiredvnodes)
369 		desiredvnodes = usevnodes;
370 #endif
371 	vfsinit();
372 
373 	/* Initialize fstrans. */
374 	fstrans_init();
375 
376 	/* Initialize the select()/poll() system calls. */
377 	selsysinit();
378 
379 	/* Initialize asynchronous I/O. */
380 	aio_sysinit();
381 
382 #if NSYSMON_TASKQ > 0
383 	sysmon_task_queue_preinit();
384 #endif
385 
386 #if NSYSMON_ENVSYS > 0
387 	sysmon_envsys_init();
388 #endif
389 
390 #if NSYSMON_POWER > 0
391 	sysmon_power_init();
392 #endif
393 #ifdef __HAVE_TIMECOUNTER
394 	inittimecounter();
395 	ntp_init();
396 #endif /* __HAVE_TIMECOUNTER */
397 
398 	/* Initialize the device switch tables. */
399 	devsw_init();
400 
401 	/* Initialize the disk wedge subsystem. */
402 	dkwedge_init();
403 
404 	/* Configure the system hardware.  This will enable interrupts. */
405 	configure();
406 
407 #if defined(__SSP__) || defined(__SSP_ALL__)
408 	{
409 #ifdef DIAGNOSTIC
410 		printf("Initializing SSP:");
411 #endif
412 		/*
413 		 * We initialize ssp here carefully:
414 		 *	1. after we got some entropy
415 		 *	2. without calling a function
416 		 */
417 		size_t i;
418 		long guard[__arraycount(__stack_chk_guard)];
419 
420 		arc4randbytes(guard, sizeof(guard));
421 		for (i = 0; i < __arraycount(guard); i++)
422 			__stack_chk_guard[i] = guard[i];
423 #ifdef DIAGNOSTIC
424 		for (i = 0; i < __arraycount(guard); i++)
425 			printf("%lx ", guard[i]);
426 		printf("\n");
427 #endif
428 	}
429 #endif
430 	ubc_init();		/* must be after autoconfig */
431 
432 	/* Lock the kernel on behalf of proc0. */
433 	KERNEL_LOCK(1, l);
434 
435 #ifdef SYSTRACE
436 	systrace_init();
437 #endif
438 
439 #ifdef SYSVSHM
440 	/* Initialize System V style shared memory. */
441 	shminit();
442 #endif
443 
444 #ifdef SYSVSEM
445 	/* Initialize System V style semaphores. */
446 	seminit();
447 #endif
448 
449 #ifdef SYSVMSG
450 	/* Initialize System V style message queues. */
451 	msginit();
452 #endif
453 
454 #ifdef P1003_1B_SEMAPHORE
455 	/* Initialize posix semaphores */
456 	ksem_init();
457 #endif
458 
459 #if NVERIEXEC > 0
460 	/*
461 	 * Initialise the Veriexec subsystem.
462 	 */
463 	veriexec_init();
464 #endif /* NVERIEXEC > 0 */
465 
466 #if defined(PAX_MPROTECT) || defined(PAX_SEGVGUARD)
467 	pax_init();
468 #endif /* PAX_MPROTECT || PAX_SEGVGUARD */
469 
470 	/* Attach pseudo-devices. */
471 	for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
472 		(*pdev->pdev_attach)(pdev->pdev_count);
473 
474 #ifdef	FAST_IPSEC
475 	/* Attach network crypto subsystem */
476 	ipsec_attach();
477 #endif
478 
479 	/*
480 	 * Initialize protocols.  Block reception of incoming packets
481 	 * until everything is ready.
482 	 */
483 	s = splnet();
484 	ifinit();
485 	domaininit();
486 	if_attachdomain();
487 	splx(s);
488 
489 #ifdef GPROF
490 	/* Initialize kernel profiling. */
491 	kmstartup();
492 #endif
493 
494 	/* Initialize system accouting. */
495 	acct_init();
496 
497 #ifndef PIPE_SOCKETPAIR
498 	/* Initialize pipes. */
499 	pipe_init();
500 #endif
501 
502 	/* Setup the scheduler */
503 	sched_init();
504 
505 #ifdef KTRACE
506 	/* Initialize ktrace. */
507 	ktrinit();
508 #endif
509 
510 	/* Initialize the UUID system calls. */
511 	uuid_init();
512 
513 	/*
514 	 * Create process 1 (init(8)).  We do this now, as Unix has
515 	 * historically had init be process 1, and changing this would
516 	 * probably upset a lot of people.
517 	 *
518 	 * Note that process 1 won't immediately exec init(8), but will
519 	 * wait for us to inform it that the root file system has been
520 	 * mounted.
521 	 */
522 	if (fork1(l, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL, &initproc))
523 		panic("fork init");
524 
525 	/*
526 	 * Now that device driver threads have been created, wait for
527 	 * them to finish any deferred autoconfiguration.  Note we don't
528 	 * need to lock this semaphore, since we haven't booted any
529 	 * secondary processors, yet.
530 	 */
531 	while (config_pending)
532 		(void) tsleep(&config_pending, PWAIT, "cfpend", 0);
533 
534 	/*
535 	 * Finalize configuration now that all real devices have been
536 	 * found.  This needs to be done before the root device is
537 	 * selected, since finalization may create the root device.
538 	 */
539 	config_finalize();
540 
541 	/*
542 	 * Now that autoconfiguration has completed, we can determine
543 	 * the root and dump devices.
544 	 */
545 	cpu_rootconf();
546 	cpu_dumpconf();
547 
548 	/* Mount the root file system. */
549 	do {
550 		domountroothook();
551 		if ((error = vfs_mountroot())) {
552 			printf("cannot mount root, error = %d\n", error);
553 			boothowto |= RB_ASKNAME;
554 			setroot(root_device,
555 			    (rootdev != NODEV) ? DISKPART(rootdev) : 0);
556 		}
557 	} while (error != 0);
558 	mountroothook_destroy();
559 
560 	/*
561 	 * Initialise the time-of-day clock, passing the time recorded
562 	 * in the root filesystem (if any) for use by systems that
563 	 * don't have a non-volatile time-of-day device.
564 	 */
565 	inittodr(rootfstime);
566 
567 	CIRCLEQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
568 	CIRCLEQ_FIRST(&mountlist)->mnt_op->vfs_refcount++;
569 
570 	/*
571 	 * Get the vnode for '/'.  Set filedesc0.fd_fd.fd_cdir to
572 	 * reference it.
573 	 */
574 	error = VFS_ROOT(CIRCLEQ_FIRST(&mountlist), &rootvnode);
575 	if (error)
576 		panic("cannot find root vnode, error=%d", error);
577 	cwdi0.cwdi_cdir = rootvnode;
578 	VREF(cwdi0.cwdi_cdir);
579 	VOP_UNLOCK(rootvnode, 0);
580 	cwdi0.cwdi_rdir = NULL;
581 
582 	/*
583 	 * Now that root is mounted, we can fixup initproc's CWD
584 	 * info.  All other processes are kthreads, which merely
585 	 * share proc0's CWD info.
586 	 */
587 	initproc->p_cwdi->cwdi_cdir = rootvnode;
588 	VREF(initproc->p_cwdi->cwdi_cdir);
589 	initproc->p_cwdi->cwdi_rdir = NULL;
590 
591 	/*
592 	 * Now can look at time, having had a chance to verify the time
593 	 * from the file system.  Reset l->l_rtime as it may have been
594 	 * munched in mi_switch() after the time got set.
595 	 */
596 #ifdef __HAVE_TIMECOUNTER
597 	getmicrotime(&time);
598 #else
599 	mono_time = time;
600 #endif
601 	boottime = time;
602 	mutex_enter(&proclist_lock);
603 	LIST_FOREACH(p, &allproc, p_list) {
604 		KASSERT((p->p_flag & PK_MARKER) == 0);
605 		mutex_enter(&p->p_smutex);
606 		p->p_stats->p_start = time;
607 		LIST_FOREACH(l, &p->p_lwps, l_sibling) {
608 			lwp_lock(l);
609 			l->l_cpu->ci_schedstate.spc_runtime = time;
610 			l->l_rtime.tv_sec = l->l_rtime.tv_usec = 0;
611 			lwp_unlock(l);
612 		}
613 		mutex_exit(&p->p_smutex);
614 	}
615 	mutex_exit(&proclist_lock);
616 
617 	for (CPU_INFO_FOREACH(cii, ci)) {
618 		ci->ci_schedstate.spc_lastmod = time_second;
619 	}
620 
621 	/* Create the pageout daemon kernel thread. */
622 	uvm_swap_init();
623 	if (kthread_create(PVM, 0, NULL, uvm_pageout,
624 	    NULL, NULL, "pgdaemon"))
625 		panic("fork pagedaemon");
626 
627 	/* Create the filesystem syncer kernel thread. */
628 	if (kthread_create(PINOD, 0, NULL, sched_sync, NULL, NULL, "ioflush"))
629 		panic("fork syncer");
630 
631 	/* Create the aiodone daemon kernel thread. */
632 	if (workqueue_create(&uvm.aiodone_queue, "aiodoned",
633 	    uvm_aiodone_worker, NULL, PVM, IPL_BIO, 0))
634 		panic("fork aiodoned");
635 
636 	vmem_rehash_start();
637 
638 #if defined(MULTIPROCESSOR)
639 	/* Boot the secondary processors. */
640 	cpu_boot_secondary_processors();
641 #endif
642 
643 	/* Initialize exec structures */
644 	exec_init(1);
645 
646 	/*
647 	 * Okay, now we can let init(8) exec!  It's off to userland!
648 	 */
649 	start_init_exec = 1;
650 	wakeup(&start_init_exec);
651 
652 	/* The scheduler is an infinite loop. */
653 	uvm_scheduler();
654 	/* NOTREACHED */
655 }
656 
657 static void
658 check_console(struct lwp *l)
659 {
660 	struct nameidata nd;
661 	int error;
662 
663 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", l);
664 	error = namei(&nd);
665 	if (error == 0)
666 		vrele(nd.ni_vp);
667 	else if (error == ENOENT)
668 		printf("warning: no /dev/console\n");
669 	else
670 		printf("warning: lookup /dev/console: error %d\n", error);
671 }
672 
673 /*
674  * List of paths to try when searching for "init".
675  */
676 static const char *initpaths[] = {
677 	"/sbin/init",
678 	"/sbin/oinit",
679 	"/sbin/init.bak",
680 	NULL,
681 };
682 
683 /*
684  * Start the initial user process; try exec'ing each pathname in "initpaths".
685  * The program is invoked with one argument containing the boot flags.
686  */
687 static void
688 start_init(void *arg)
689 {
690 	struct lwp *l = arg;
691 	struct proc *p = l->l_proc;
692 	vaddr_t addr;
693 	struct sys_execve_args /* {
694 		syscallarg(const char *) path;
695 		syscallarg(char * const *) argp;
696 		syscallarg(char * const *) envp;
697 	} */ args;
698 	int options, i, error;
699 	register_t retval[2];
700 	char flags[4], *flagsp;
701 	const char *path, *slash;
702 	char *ucp, **uap, *arg0, *arg1 = NULL;
703 	char ipath[129];
704 	int ipx, len;
705 
706 	/*
707 	 * Now in process 1.
708 	 */
709 	strncpy(p->p_comm, "init", MAXCOMLEN);
710 
711 	/*
712 	 * Wait for main() to tell us that it's safe to exec.
713 	 */
714 	while (start_init_exec == 0)
715 		(void) tsleep(&start_init_exec, PWAIT, "initexec", 0);
716 
717 	/*
718 	 * This is not the right way to do this.  We really should
719 	 * hand-craft a descriptor onto /dev/console to hand to init,
720 	 * but that's a _lot_ more work, and the benefit from this easy
721 	 * hack makes up for the "good is the enemy of the best" effect.
722 	 */
723 	check_console(l);
724 
725 	/*
726 	 * Need just enough stack to hold the faked-up "execve()" arguments.
727 	 */
728 	addr = (vaddr_t)STACK_ALLOC(USRSTACK, PAGE_SIZE);
729 	if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
730                     NULL, UVM_UNKNOWN_OFFSET, 0,
731                     UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
732 		    UVM_ADV_NORMAL,
733                     UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)) != 0)
734 		panic("init: couldn't allocate argument space");
735 	p->p_vmspace->vm_maxsaddr = (void *)STACK_MAX(addr, PAGE_SIZE);
736 
737 	ipx = 0;
738 	while (1) {
739 		if (boothowto & RB_ASKNAME) {
740 			printf("init path");
741 			if (initpaths[ipx])
742 				printf(" (default %s)", initpaths[ipx]);
743 			printf(": ");
744 			len = cngetsn(ipath, sizeof(ipath)-1);
745 			if (len == 0) {
746 				if (initpaths[ipx])
747 					path = initpaths[ipx++];
748 				else
749 					continue;
750 			} else {
751 				ipath[len] = '\0';
752 				path = ipath;
753 			}
754 		} else {
755 			if ((path = initpaths[ipx++]) == NULL)
756 				break;
757 		}
758 
759 		ucp = (char *)USRSTACK;
760 
761 		/*
762 		 * Construct the boot flag argument.
763 		 */
764 		flagsp = flags;
765 		*flagsp++ = '-';
766 		options = 0;
767 
768 		if (boothowto & RB_SINGLE) {
769 			*flagsp++ = 's';
770 			options = 1;
771 		}
772 #ifdef notyet
773 		if (boothowto & RB_FASTBOOT) {
774 			*flagsp++ = 'f';
775 			options = 1;
776 		}
777 #endif
778 
779 		/*
780 		 * Move out the flags (arg 1), if necessary.
781 		 */
782 		if (options != 0) {
783 			*flagsp++ = '\0';
784 			i = flagsp - flags;
785 #ifdef DEBUG
786 			printf("init: copying out flags `%s' %d\n", flags, i);
787 #endif
788 			arg1 = STACK_ALLOC(ucp, i);
789 			ucp = STACK_MAX(arg1, i);
790 			(void)copyout((void *)flags, arg1, i);
791 		}
792 
793 		/*
794 		 * Move out the file name (also arg 0).
795 		 */
796 		i = strlen(path) + 1;
797 #ifdef DEBUG
798 		printf("init: copying out path `%s' %d\n", path, i);
799 #else
800 		if (boothowto & RB_ASKNAME || path != initpaths[0])
801 			printf("init: trying %s\n", path);
802 #endif
803 		arg0 = STACK_ALLOC(ucp, i);
804 		ucp = STACK_MAX(arg0, i);
805 		(void)copyout(path, arg0, i);
806 
807 		/*
808 		 * Move out the arg pointers.
809 		 */
810 		ucp = (void *)STACK_ALIGN(ucp, ALIGNBYTES);
811 		uap = (char **)STACK_ALLOC(ucp, sizeof(char *) * 3);
812 		SCARG(&args, path) = arg0;
813 		SCARG(&args, argp) = uap;
814 		SCARG(&args, envp) = NULL;
815 		slash = strrchr(path, '/');
816 		if (slash)
817 			(void)suword((void *)uap++,
818 			    (long)arg0 + (slash + 1 - path));
819 		else
820 			(void)suword((void *)uap++, (long)arg0);
821 		if (options != 0)
822 			(void)suword((void *)uap++, (long)arg1);
823 		(void)suword((void *)uap++, 0);	/* terminator */
824 
825 		/*
826 		 * Now try to exec the program.  If can't for any reason
827 		 * other than it doesn't exist, complain.
828 		 */
829 		error = sys_execve(l, &args, retval);
830 		if (error == 0 || error == EJUSTRETURN) {
831 			KERNEL_UNLOCK_LAST(l);
832 			return;
833 		}
834 		printf("exec %s: error %d\n", path, error);
835 	}
836 	printf("init: not found\n");
837 	panic("no init");
838 }
839