init_main.c revision 1.208 1 /* $NetBSD: init_main.c,v 1.208 2002/10/01 18:11:58 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1995 Christopher G. Demetriou. All rights reserved.
5 * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
6 * The Regents of the University of California. All rights reserved.
7 * (c) UNIX System Laboratories, Inc.
8 * All or some portions of this file are derived from material licensed
9 * to the University of California by American Telephone and Telegraph
10 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
11 * the permission of UNIX System Laboratories, Inc.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. All advertising materials mentioning features or use of this software
22 * must display the following acknowledgement:
23 * This product includes software developed by the University of
24 * California, Berkeley and its contributors.
25 * 4. Neither the name of the University nor the names of its contributors
26 * may be used to endorse or promote products derived from this software
27 * without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * SUCH DAMAGE.
40 *
41 * @(#)init_main.c 8.16 (Berkeley) 5/14/95
42 */
43
44 #include <sys/cdefs.h>
45 __KERNEL_RCSID(0, "$NetBSD: init_main.c,v 1.208 2002/10/01 18:11:58 thorpej Exp $");
46
47 #include "fs_nfs.h"
48 #include "opt_nfsserver.h"
49 #include "opt_sysv.h"
50 #include "opt_maxuprc.h"
51 #include "opt_multiprocessor.h"
52 #include "opt_pipe.h"
53 #include "opt_syscall_debug.h"
54 #include "opt_systrace.h"
55
56 #include "rnd.h"
57
58 #include <sys/param.h>
59 #include <sys/acct.h>
60 #include <sys/filedesc.h>
61 #include <sys/file.h>
62 #include <sys/errno.h>
63 #include <sys/callout.h>
64 #include <sys/kernel.h>
65 #include <sys/mount.h>
66 #include <sys/proc.h>
67 #include <sys/kthread.h>
68 #include <sys/resourcevar.h>
69 #include <sys/signalvar.h>
70 #include <sys/systm.h>
71 #include <sys/vnode.h>
72 #include <sys/tty.h>
73 #include <sys/conf.h>
74 #include <sys/disklabel.h>
75 #include <sys/buf.h>
76 #include <sys/device.h>
77 #include <sys/disk.h>
78 #include <sys/exec.h>
79 #include <sys/socketvar.h>
80 #include <sys/protosw.h>
81 #include <sys/reboot.h>
82 #include <sys/user.h>
83 #include <sys/sysctl.h>
84 #ifdef SYSVSHM
85 #include <sys/shm.h>
86 #endif
87 #ifdef SYSVSEM
88 #include <sys/sem.h>
89 #endif
90 #ifdef SYSVMSG
91 #include <sys/msg.h>
92 #endif
93 #ifdef SYSTRACE
94 #include <sys/systrace.h>
95 #endif
96 #include <sys/domain.h>
97 #include <sys/mbuf.h>
98 #include <sys/namei.h>
99 #if NRND > 0
100 #include <sys/rnd.h>
101 #endif
102 #ifndef PIPE_SOCKETPAIR
103 #include <sys/pipe.h>
104 #endif
105
106 #include <sys/syscall.h>
107 #include <sys/syscallargs.h>
108
109 #include <ufs/ufs/quota.h>
110
111 #include <miscfs/genfs/genfs.h>
112 #include <miscfs/syncfs/syncfs.h>
113
114 #include <machine/cpu.h>
115
116 #include <uvm/uvm.h>
117
118 #include <dev/cons.h>
119
120 #include <net/if.h>
121 #include <net/raw_cb.h>
122
123 const char copyright[] =
124 "Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002\n"
125 " The NetBSD Foundation, Inc. All rights reserved.\n"
126 "Copyright (c) 1982, 1986, 1989, 1991, 1993\n"
127 " The Regents of the University of California. All rights reserved.\n"
128 "\n";
129
130 /* Components of the first process -- never freed. */
131 struct session session0;
132 struct pgrp pgrp0;
133 struct proc proc0;
134 struct pcred cred0;
135 struct filedesc0 filedesc0;
136 struct cwdinfo cwdi0;
137 struct plimit limit0;
138 struct vmspace vmspace0;
139 struct sigacts sigacts0;
140 #ifndef curproc
141 struct proc *curproc = &proc0;
142 #endif
143 struct proc *initproc;
144
145 int cmask = CMASK;
146 extern struct user *proc0paddr;
147
148 struct vnode *rootvp, *swapdev_vp;
149 int boothowto;
150 int cold = 1; /* still working on startup */
151 struct timeval boottime;
152
153 __volatile int start_init_exec; /* semaphore for start_init() */
154
155 static void check_console(struct proc *p);
156 static void start_init(void *);
157 void main(void);
158
159 extern const struct emul emul_netbsd; /* defined in kern_exec.c */
160
161 /*
162 * System startup; initialize the world, create process 0, mount root
163 * filesystem, and fork to create init and pagedaemon. Most of the
164 * hard work is done in the lower-level initialization routines including
165 * startup(), which does memory initialization and autoconfiguration.
166 */
167 void
168 main(void)
169 {
170 struct proc *p;
171 struct pdevinit *pdev;
172 int s, error;
173 u_int i;
174 rlim_t lim;
175 extern struct pdevinit pdevinit[];
176 extern void schedcpu(void *);
177 #if defined(NFSSERVER) || defined(NFS)
178 extern void nfs_init(void);
179 #endif
180 #ifdef NVNODE_IMPLICIT
181 int usevnodes;
182 #endif
183
184 /*
185 * Initialize the current process pointer (curproc) before
186 * any possible traps/probes to simplify trap processing.
187 */
188 simple_lock_init(&proc0.p_raslock);
189 p = &proc0;
190 curproc = p;
191 p->p_cpu = curcpu();
192 /*
193 * Attempt to find console and initialize
194 * in case of early panic or other messages.
195 */
196 consinit();
197 printf("%s", copyright);
198
199 KERNEL_LOCK_INIT();
200
201 uvm_init();
202
203 /* Do machine-dependent initialization. */
204 cpu_startup();
205
206 /* Initialize callouts. */
207 callout_startup();
208
209 /*
210 * Initialize mbuf's. Do this now because we might attempt to
211 * allocate mbufs or mbuf clusters during autoconfiguration.
212 */
213 mbinit();
214
215 /* Initialize sockets. */
216 soinit();
217
218 /*
219 * The following 3 things must be done before autoconfiguration.
220 */
221 disk_init(); /* initialize disk list */
222 tty_init(); /* initialize tty list */
223 #if NRND > 0
224 rnd_init(); /* initialize RNG */
225 #endif
226
227 /* Initialize the sysctl subsystem. */
228 sysctl_init();
229
230 /*
231 * Initialize process and pgrp structures.
232 */
233 procinit();
234
235 /*
236 * Create process 0 (the swapper).
237 */
238 s = proclist_lock_write();
239 LIST_INSERT_HEAD(&allproc, p, p_list);
240 LIST_INSERT_HEAD(PIDHASH(p->p_pid), p, p_hash);
241 proclist_unlock_write(s);
242
243 p->p_pgrp = &pgrp0;
244 LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash);
245 LIST_INIT(&pgrp0.pg_members);
246 LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist);
247
248 pgrp0.pg_session = &session0;
249 session0.s_count = 1;
250 session0.s_sid = p->p_pid;
251 session0.s_leader = p;
252
253 /*
254 * Set P_NOCLDWAIT so that kernel threads are reparented to
255 * init(8) when they exit. init(8) can easily wait them out
256 * for us.
257 */
258 p->p_flag = P_INMEM | P_SYSTEM | P_NOCLDWAIT;
259 p->p_stat = SONPROC;
260 p->p_nice = NZERO;
261 p->p_emul = &emul_netbsd;
262 #ifdef __HAVE_SYSCALL_INTERN
263 (*p->p_emul->e_syscall_intern)(p);
264 #endif
265 strncpy(p->p_comm, "swapper", MAXCOMLEN);
266
267 callout_init(&p->p_realit_ch);
268 callout_init(&p->p_tsleep_ch);
269
270 /* Create credentials. */
271 cred0.p_refcnt = 1;
272 p->p_cred = &cred0;
273 p->p_ucred = crget();
274 p->p_ucred->cr_ngroups = 1; /* group 0 */
275
276 /* Create the file descriptor table. */
277 finit();
278 p->p_fd = &filedesc0.fd_fd;
279 fdinit1(&filedesc0);
280
281 /* Create the CWD info. */
282 p->p_cwdi = &cwdi0;
283 cwdi0.cwdi_cmask = cmask;
284 cwdi0.cwdi_refcnt = 1;
285
286 /* Create the limits structures. */
287 p->p_limit = &limit0;
288 for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++)
289 limit0.pl_rlimit[i].rlim_cur =
290 limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY;
291
292 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles;
293 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur =
294 maxfiles < NOFILE ? maxfiles : NOFILE;
295
296 limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc;
297 limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur =
298 maxproc < MAXUPRC ? maxproc : MAXUPRC;
299
300 lim = ptoa(uvmexp.free);
301 limit0.pl_rlimit[RLIMIT_RSS].rlim_max = lim;
302 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = lim;
303 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = lim / 3;
304 limit0.pl_corename = defcorename;
305 limit0.p_refcnt = 1;
306
307 /*
308 * Initialize proc0's vmspace, which uses the kernel pmap.
309 * All kernel processes (which never have user space mappings)
310 * share proc0's vmspace, and thus, the kernel pmap.
311 */
312 uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS),
313 trunc_page(VM_MAX_ADDRESS));
314 p->p_vmspace = &vmspace0;
315
316 p->p_addr = proc0paddr; /* XXX */
317
318 /*
319 * We continue to place resource usage info in the
320 * user struct so they're pageable.
321 */
322 p->p_stats = &p->p_addr->u_stats;
323
324 /*
325 * Charge root for one process.
326 */
327 (void)chgproccnt(0, 1);
328
329 rqinit();
330
331 /* Configure virtual memory system, set vm rlimits. */
332 uvm_init_limits(p);
333
334 /* Initialize the file systems. */
335 #if defined(NFSSERVER) || defined(NFS)
336 nfs_init(); /* initialize server/shared data */
337 #endif
338 #ifdef NVNODE_IMPLICIT
339 /*
340 * If maximum number of vnodes in namei vnode cache is not explicitly
341 * defined in kernel config, adjust the number such as we use roughly
342 * 0.5% of memory for vnode cache (but not less than NVNODE vnodes).
343 */
344 usevnodes = (ptoa((unsigned)physmem) / 200) / sizeof(struct vnode);
345 if (usevnodes > desiredvnodes)
346 desiredvnodes = usevnodes;
347 #endif
348 vfsinit();
349
350 /* Configure the system hardware. This will enable interrupts. */
351 configure();
352
353 ubc_init(); /* must be after autoconfig */
354
355 /* Lock the kernel on behalf of proc0. */
356 KERNEL_PROC_LOCK(p);
357
358 #ifdef SYSVSHM
359 /* Initialize System V style shared memory. */
360 shminit();
361 #endif
362
363 #ifdef SYSVSEM
364 /* Initialize System V style semaphores. */
365 seminit();
366 #endif
367
368 #ifdef SYSVMSG
369 /* Initialize System V style message queues. */
370 msginit();
371 #endif
372
373 /* Attach pseudo-devices. */
374 for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++)
375 (*pdev->pdev_attach)(pdev->pdev_count);
376
377 /*
378 * Initialize protocols. Block reception of incoming packets
379 * until everything is ready.
380 */
381 s = splnet();
382 ifinit();
383 domaininit();
384 if_attachdomain();
385 splx(s);
386
387 #ifdef GPROF
388 /* Initialize kernel profiling. */
389 kmstartup();
390 #endif
391
392 /* Initialize system accouting. */
393 acct_init();
394
395 #ifdef SYSTRACE
396 systrace_init();
397 #endif
398 /*
399 * Initialize signal-related data structures, and signal state
400 * for proc0.
401 */
402 signal_init();
403 p->p_sigacts = &sigacts0;
404 siginit(p);
405
406 /* Kick off timeout driven events by calling first time. */
407 schedcpu(NULL);
408
409 /*
410 * Create process 1 (init(8)). We do this now, as Unix has
411 * historically had init be process 1, and changing this would
412 * probably upset a lot of people.
413 *
414 * Note that process 1 won't immediately exec init(8), but will
415 * wait for us to inform it that the root file system has been
416 * mounted.
417 */
418 if (fork1(p, 0, SIGCHLD, NULL, 0, start_init, NULL, NULL, &initproc))
419 panic("fork init");
420
421 /*
422 * Create any kernel threads who's creation was deferred because
423 * initproc had not yet been created.
424 */
425 kthread_run_deferred_queue();
426
427 /*
428 * Now that device driver threads have been created, wait for
429 * them to finish any deferred autoconfiguration. Note we don't
430 * need to lock this semaphore, since we haven't booted any
431 * secondary processors, yet.
432 */
433 while (config_pending)
434 (void) tsleep((void *)&config_pending, PWAIT, "cfpend", 0);
435
436 /*
437 * Finalize configuration now that all real devices have been
438 * found. This needs to be done before the root device is
439 * selected, since finalization may create the root device.
440 */
441 config_finalize();
442
443 /*
444 * Now that autoconfiguration has completed, we can determine
445 * the root and dump devices.
446 */
447 cpu_rootconf();
448 cpu_dumpconf();
449
450 /* Mount the root file system. */
451 do {
452 domountroothook();
453 if ((error = vfs_mountroot())) {
454 printf("cannot mount root, error = %d\n", error);
455 boothowto |= RB_ASKNAME;
456 setroot(root_device,
457 (rootdev != NODEV) ? DISKPART(rootdev) : 0);
458 }
459 } while (error != 0);
460 mountroothook_destroy();
461
462 CIRCLEQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS;
463 CIRCLEQ_FIRST(&mountlist)->mnt_op->vfs_refcount++;
464
465 /*
466 * Get the vnode for '/'. Set filedesc0.fd_fd.fd_cdir to
467 * reference it.
468 */
469 if (VFS_ROOT(CIRCLEQ_FIRST(&mountlist), &rootvnode))
470 panic("cannot find root vnode");
471 cwdi0.cwdi_cdir = rootvnode;
472 VREF(cwdi0.cwdi_cdir);
473 VOP_UNLOCK(rootvnode, 0);
474 cwdi0.cwdi_rdir = NULL;
475
476 /*
477 * Now that root is mounted, we can fixup initproc's CWD
478 * info. All other processes are kthreads, which merely
479 * share proc0's CWD info.
480 */
481 initproc->p_cwdi->cwdi_cdir = rootvnode;
482 VREF(initproc->p_cwdi->cwdi_cdir);
483 initproc->p_cwdi->cwdi_rdir = NULL;
484
485 /*
486 * Now can look at time, having had a chance to verify the time
487 * from the file system. Reset p->p_rtime as it may have been
488 * munched in mi_switch() after the time got set.
489 */
490 proclist_lock_read();
491 s = splsched();
492 for (p = LIST_FIRST(&allproc); p != NULL;
493 p = LIST_NEXT(p, p_list)) {
494 p->p_stats->p_start = mono_time = boottime = time;
495 if (p->p_cpu != NULL)
496 p->p_cpu->ci_schedstate.spc_runtime = time;
497 p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0;
498 }
499 splx(s);
500 proclist_unlock_read();
501
502 /* Create the pageout daemon kernel thread. */
503 uvm_swap_init();
504 if (kthread_create1(uvm_pageout, NULL, NULL, "pagedaemon"))
505 panic("fork pagedaemon");
506
507 /* Create the process reaper kernel thread. */
508 if (kthread_create1(reaper, NULL, NULL, "reaper"))
509 panic("fork reaper");
510
511 /* Create the filesystem syncer kernel thread. */
512 if (kthread_create1(sched_sync, NULL, NULL, "ioflush"))
513 panic("fork syncer");
514
515 /* Create the aiodone daemon kernel thread. */
516 if (kthread_create1(uvm_aiodone_daemon, NULL, NULL, "aiodoned"))
517 panic("fork aiodoned");
518
519 #if defined(MULTIPROCESSOR)
520 /* Boot the secondary processors. */
521 cpu_boot_secondary_processors();
522 #endif
523
524 /* Initialize exec structures */
525 exec_init(1);
526
527 #ifndef PIPE_SOCKETPAIR
528 /* Initialize pipe structures */
529 pipe_init();
530 #endif
531
532 /*
533 * Okay, now we can let init(8) exec! It's off to userland!
534 */
535 start_init_exec = 1;
536 wakeup((void *)&start_init_exec);
537
538 /* The scheduler is an infinite loop. */
539 uvm_scheduler();
540 /* NOTREACHED */
541 }
542
543 static void
544 check_console(struct proc *p)
545 {
546 struct nameidata nd;
547 int error;
548
549 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p);
550 error = namei(&nd);
551 if (error == 0)
552 vrele(nd.ni_vp);
553 else if (error == ENOENT)
554 printf("warning: no /dev/console\n");
555 else
556 printf("warning: lookup /dev/console: error %d\n", error);
557 }
558
559 /*
560 * List of paths to try when searching for "init".
561 */
562 static const char *initpaths[] = {
563 "/sbin/init",
564 "/sbin/oinit",
565 "/sbin/init.bak",
566 NULL,
567 };
568
569 /*
570 * Start the initial user process; try exec'ing each pathname in "initpaths".
571 * The program is invoked with one argument containing the boot flags.
572 */
573 static void
574 start_init(void *arg)
575 {
576 struct proc *p = arg;
577 vaddr_t addr;
578 struct sys_execve_args /* {
579 syscallarg(const char *) path;
580 syscallarg(char * const *) argp;
581 syscallarg(char * const *) envp;
582 } */ args;
583 int options, i, error;
584 register_t retval[2];
585 char flags[4], *flagsp;
586 const char *path, *slash;
587 char *ucp, **uap, *arg0, *arg1 = NULL;
588 char ipath[129];
589 int ipx, len;
590
591 /*
592 * Now in process 1.
593 */
594 strncpy(p->p_comm, "init", MAXCOMLEN);
595
596 /*
597 * Wait for main() to tell us that it's safe to exec.
598 */
599 while (start_init_exec == 0)
600 (void) tsleep((void *)&start_init_exec, PWAIT, "initexec", 0);
601
602 /*
603 * This is not the right way to do this. We really should
604 * hand-craft a descriptor onto /dev/console to hand to init,
605 * but that's a _lot_ more work, and the benefit from this easy
606 * hack makes up for the "good is the enemy of the best" effect.
607 */
608 check_console(p);
609
610 /*
611 * Need just enough stack to hold the faked-up "execve()" arguments.
612 */
613 addr = USRSTACK - PAGE_SIZE;
614 if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE,
615 NULL, UVM_UNKNOWN_OFFSET, 0,
616 UVM_MAPFLAG(UVM_PROT_ALL, UVM_PROT_ALL, UVM_INH_COPY,
617 UVM_ADV_NORMAL,
618 UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW)) != 0)
619 panic("init: couldn't allocate argument space");
620 p->p_vmspace->vm_maxsaddr = (caddr_t)addr;
621
622 ipx = 0;
623 while (1) {
624 if (boothowto & RB_ASKNAME) {
625 printf("init path");
626 if (initpaths[ipx])
627 printf(" (default %s)", initpaths[ipx]);
628 printf(": ");
629 len = cngetsn(ipath, sizeof(ipath)-1);
630 if (len == 0) {
631 if (initpaths[ipx])
632 path = initpaths[ipx++];
633 else
634 continue;
635 } else {
636 ipath[len] = '\0';
637 path = ipath;
638 }
639 } else {
640 if ((path = initpaths[ipx++]) == NULL)
641 break;
642 }
643
644 ucp = (char *)(addr + PAGE_SIZE);
645
646 /*
647 * Construct the boot flag argument.
648 */
649 flagsp = flags;
650 *flagsp++ = '-';
651 options = 0;
652
653 if (boothowto & RB_SINGLE) {
654 *flagsp++ = 's';
655 options = 1;
656 }
657 #ifdef notyet
658 if (boothowto & RB_FASTBOOT) {
659 *flagsp++ = 'f';
660 options = 1;
661 }
662 #endif
663
664 /*
665 * Move out the flags (arg 1), if necessary.
666 */
667 if (options != 0) {
668 *flagsp++ = '\0';
669 i = flagsp - flags;
670 #ifdef DEBUG
671 printf("init: copying out flags `%s' %d\n", flags, i);
672 #endif
673 (void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i);
674 arg1 = ucp;
675 }
676
677 /*
678 * Move out the file name (also arg 0).
679 */
680 i = strlen(path) + 1;
681 #ifdef DEBUG
682 printf("init: copying out path `%s' %d\n", path, i);
683 #else
684 if (boothowto & RB_ASKNAME || path != initpaths[0])
685 printf("init: trying %s\n", path);
686 #endif
687 (void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i);
688 arg0 = ucp;
689
690 /*
691 * Move out the arg pointers.
692 */
693 uap = (char **)((long)ucp & ~ALIGNBYTES);
694 (void)suword((caddr_t)--uap, 0); /* terminator */
695 if (options != 0)
696 (void)suword((caddr_t)--uap, (long)arg1);
697 slash = strrchr(path, '/');
698 if (slash)
699 (void)suword((caddr_t)--uap,
700 (long)arg0 + (slash + 1 - path));
701 else
702 (void)suword((caddr_t)--uap, (long)arg0);
703
704 /*
705 * Point at the arguments.
706 */
707 SCARG(&args, path) = arg0;
708 SCARG(&args, argp) = uap;
709 SCARG(&args, envp) = NULL;
710
711 /*
712 * Now try to exec the program. If can't for any reason
713 * other than it doesn't exist, complain.
714 */
715 error = sys_execve(p, &args, retval);
716 if (error == 0 || error == EJUSTRETURN) {
717 KERNEL_PROC_UNLOCK(p);
718 return;
719 }
720 printf("exec %s: error %d\n", path, error);
721 }
722 printf("init: not found\n");
723 panic("no init");
724 }
725