1 /* $OpenBSD: init_main.c,v 1.159 2009/04/19 17:53:38 deraadt 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/core.h> 43 #include <sys/filedesc.h> 44 #include <sys/file.h> 45 #include <sys/errno.h> 46 #include <sys/exec.h> 47 #include <sys/kernel.h> 48 #include <sys/kthread.h> 49 #include <sys/mount.h> 50 #include <sys/proc.h> 51 #include <sys/resourcevar.h> 52 #include <sys/signalvar.h> 53 #include <sys/systm.h> 54 #include <sys/namei.h> 55 #include <sys/vnode.h> 56 #include <sys/tty.h> 57 #include <sys/conf.h> 58 #include <sys/buf.h> 59 #include <sys/device.h> 60 #include <sys/socketvar.h> 61 #include <sys/lockf.h> 62 #include <sys/protosw.h> 63 #include <sys/reboot.h> 64 #include <sys/user.h> 65 #ifdef SYSVSHM 66 #include <sys/shm.h> 67 #endif 68 #ifdef SYSVSEM 69 #include <sys/sem.h> 70 #endif 71 #ifdef SYSVMSG 72 #include <sys/msg.h> 73 #endif 74 #include <sys/domain.h> 75 #include <sys/mbuf.h> 76 #include <sys/pipe.h> 77 #include <sys/workq.h> 78 79 #include <sys/syscall.h> 80 #include <sys/syscallargs.h> 81 82 #include <dev/rndvar.h> 83 84 #include <ufs/ufs/quota.h> 85 86 #include <machine/cpu.h> 87 88 #include <uvm/uvm.h> 89 90 #include <net/if.h> 91 #include <net/raw_cb.h> 92 93 #if defined(CRYPTO) 94 #include <crypto/cryptodev.h> 95 #include <crypto/cryptosoft.h> 96 #endif 97 98 #if defined(NFSSERVER) || defined(NFSCLIENT) 99 extern void nfs_init(void); 100 #endif 101 102 #include "vscsi.h" 103 #include "softraid.h" 104 105 const char copyright[] = 106 "Copyright (c) 1982, 1986, 1989, 1991, 1993\n" 107 "\tThe Regents of the University of California. All rights reserved.\n" 108 "Copyright (c) 1995-2009 OpenBSD. All rights reserved. http://www.OpenBSD.org\n"; 109 110 /* Components of the first process -- never freed. */ 111 struct session session0; 112 struct pgrp pgrp0; 113 struct proc proc0; 114 struct process process0; 115 struct pcred cred0; 116 struct plimit limit0; 117 struct vmspace vmspace0; 118 struct sigacts sigacts0; 119 struct proc *initproc; 120 121 int cmask = CMASK; 122 extern struct user *proc0paddr; 123 124 struct vnode *rootvp, *swapdev_vp; 125 int boothowto; 126 struct timeval boottime; 127 int ncpus = 1; 128 int ncpusfound = 1; /* number of cpus we find */ 129 __volatile int start_init_exec; /* semaphore for start_init() */ 130 131 #if !defined(NO_PROPOLICE) 132 long __guard[8]; 133 #endif 134 135 /* XXX return int so gcc -Werror won't complain */ 136 int main(void *); 137 void check_console(struct proc *); 138 void start_init(void *); 139 void start_cleaner(void *); 140 void start_update(void *); 141 void start_reaper(void *); 142 void init_crypto(void); 143 void init_exec(void); 144 void kqueue_init(void); 145 void workq_init(void); 146 147 extern char sigcode[], esigcode[]; 148 #ifdef SYSCALL_DEBUG 149 extern char *syscallnames[]; 150 #endif 151 152 struct emul emul_native = { 153 "native", 154 NULL, 155 sendsig, 156 SYS_syscall, 157 SYS_MAXSYSCALL, 158 sysent, 159 #ifdef SYSCALL_DEBUG 160 syscallnames, 161 #else 162 NULL, 163 #endif 164 0, 165 copyargs, 166 setregs, 167 NULL, 168 coredump_trad, 169 sigcode, 170 esigcode, 171 EMUL_ENABLED | EMUL_NATIVE, 172 }; 173 174 175 /* 176 * System startup; initialize the world, create process 0, mount root 177 * filesystem, and fork to create init and pagedaemon. Most of the 178 * hard work is done in the lower-level initialization routines including 179 * startup(), which does memory initialization and autoconfiguration. 180 */ 181 /* XXX return int, so gcc -Werror won't complain */ 182 int 183 main(void *framep) 184 { 185 struct proc *p; 186 struct pdevinit *pdev; 187 struct timeval rtv; 188 quad_t lim; 189 int s, i; 190 extern struct pdevinit pdevinit[]; 191 extern void scheduler_start(void); 192 extern void disk_init(void); 193 extern void endtsleep(void *); 194 extern void realitexpire(void *); 195 196 /* 197 * Initialize the current process pointer (curproc) before 198 * any possible traps/probes to simplify trap processing. 199 */ 200 curproc = p = &proc0; 201 p->p_cpu = curcpu(); 202 203 /* 204 * Initialize timeouts. 205 */ 206 timeout_startup(); 207 208 /* 209 * Attempt to find console and initialize 210 * in case of early panic or other messages. 211 */ 212 config_init(); /* init autoconfiguration data structures */ 213 consinit(); 214 215 printf("%s\n", copyright); 216 217 KERNEL_LOCK_INIT(); 218 219 uvm_init(); 220 disk_init(); /* must come before autoconfiguration */ 221 tty_init(); /* initialise tty's */ 222 cpu_startup(); 223 224 /* 225 * Initialize mbuf's. Do this now because we might attempt to 226 * allocate mbufs or mbuf clusters during autoconfiguration. 227 */ 228 mbinit(); 229 230 /* Initialize sockets. */ 231 soinit(); 232 233 /* 234 * Initialize process and pgrp structures. 235 */ 236 procinit(); 237 238 /* Initialize file locking. */ 239 lf_init(); 240 241 /* 242 * Initialize filedescriptors. 243 */ 244 filedesc_init(); 245 246 /* 247 * Initialize pipes. 248 */ 249 pipe_init(); 250 251 /* 252 * Initialize kqueues. 253 */ 254 kqueue_init(); 255 256 /* 257 * Create process 0 (the swapper). 258 */ 259 260 process0.ps_mainproc = p; 261 TAILQ_INIT(&process0.ps_threads); 262 TAILQ_INSERT_TAIL(&process0.ps_threads, p, p_thr_link); 263 process0.ps_refcnt = 1; 264 p->p_p = &process0; 265 266 LIST_INSERT_HEAD(&allproc, p, p_list); 267 p->p_pgrp = &pgrp0; 268 LIST_INSERT_HEAD(PIDHASH(0), p, p_hash); 269 LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash); 270 LIST_INIT(&pgrp0.pg_members); 271 LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist); 272 273 pgrp0.pg_session = &session0; 274 session0.s_count = 1; 275 session0.s_leader = p; 276 277 atomic_setbits_int(&p->p_flag, P_SYSTEM | P_NOCLDWAIT); 278 p->p_stat = SONPROC; 279 p->p_nice = NZERO; 280 p->p_emul = &emul_native; 281 bcopy("swapper", p->p_comm, sizeof ("swapper")); 282 283 /* Init timeouts. */ 284 timeout_set(&p->p_sleep_to, endtsleep, p); 285 timeout_set(&p->p_realit_to, realitexpire, p); 286 287 /* Create credentials. */ 288 cred0.p_refcnt = 1; 289 p->p_cred = &cred0; 290 p->p_ucred = crget(); 291 p->p_ucred->cr_ngroups = 1; /* group 0 */ 292 293 /* Initialize signal state for process 0. */ 294 signal_init(); 295 p->p_sigacts = &sigacts0; 296 siginit(p); 297 298 /* Create the file descriptor table. */ 299 p->p_fd = fdinit(NULL); 300 301 /* Create the limits structures. */ 302 p->p_p->ps_limit = &limit0; 303 for (i = 0; i < nitems(p->p_rlimit); i++) 304 limit0.pl_rlimit[i].rlim_cur = 305 limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY; 306 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur = NOFILE; 307 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = MIN(NOFILE_MAX, 308 (maxfiles - NOFILE > NOFILE) ? maxfiles - NOFILE : NOFILE); 309 limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur = MAXUPRC; 310 lim = ptoa(uvmexp.free); 311 limit0.pl_rlimit[RLIMIT_RSS].rlim_max = lim; 312 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = lim; 313 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = lim / 3; 314 limit0.p_refcnt = 1; 315 316 /* Allocate a prototype map so we have something to fork. */ 317 uvmspace_init(&vmspace0, pmap_kernel(), round_page(VM_MIN_ADDRESS), 318 trunc_page(VM_MAX_ADDRESS), TRUE, TRUE); 319 p->p_vmspace = &vmspace0; 320 321 p->p_addr = proc0paddr; /* XXX */ 322 323 /* 324 * We continue to place resource usage info in the 325 * user struct so they're pageable. 326 */ 327 p->p_stats = &p->p_addr->u_stats; 328 329 /* 330 * Charge root for one process. 331 */ 332 (void)chgproccnt(0, 1); 333 334 /* Initialize run queues */ 335 sched_init_runqueues(); 336 sleep_queue_init(); 337 sched_init_cpu(curcpu()); 338 339 /* Initialize work queues */ 340 workq_init(); 341 342 /* Configure the devices */ 343 cpu_configure(); 344 345 /* Configure virtual memory system, set vm rlimits. */ 346 uvm_init_limits(p); 347 348 /* Initialize the file systems. */ 349 #if defined(NFSSERVER) || defined(NFSCLIENT) 350 nfs_init(); /* initialize server/shared data */ 351 #endif 352 vfsinit(); 353 354 /* Start real time and statistics clocks. */ 355 initclocks(); 356 357 /* Lock the kernel on behalf of proc0. */ 358 KERNEL_PROC_LOCK(p); 359 360 #ifdef SYSVSHM 361 /* Initialize System V style shared memory. */ 362 shminit(); 363 #endif 364 365 #ifdef SYSVSEM 366 /* Initialize System V style semaphores. */ 367 seminit(); 368 #endif 369 370 #ifdef SYSVMSG 371 /* Initialize System V style message queues. */ 372 msginit(); 373 #endif 374 375 /* Attach pseudo-devices. */ 376 randomattach(); 377 for (pdev = pdevinit; pdev->pdev_attach != NULL; pdev++) 378 if (pdev->pdev_count > 0) 379 (*pdev->pdev_attach)(pdev->pdev_count); 380 381 #ifdef CRYPTO 382 swcr_init(); 383 #endif /* CRYPTO */ 384 385 /* 386 * Initialize protocols. Block reception of incoming packets 387 * until everything is ready. 388 */ 389 s = splnet(); 390 ifinit(); 391 domaininit(); 392 if_attachdomain(); 393 splx(s); 394 395 #ifdef GPROF 396 /* Initialize kernel profiling. */ 397 kmstartup(); 398 #endif 399 400 #if !defined(NO_PROPOLICE) 401 { 402 volatile long newguard[8]; 403 404 arc4random_buf((long *)newguard, sizeof(newguard)); 405 406 for (i = nitems(__guard) - 1; i; i--) 407 __guard[i] = newguard[i]; 408 } 409 #endif 410 411 /* init exec and emul */ 412 init_exec(); 413 414 /* Start the scheduler */ 415 scheduler_start(); 416 417 /* 418 * Create process 1 (init(8)). We do this now, as Unix has 419 * historically had init be process 1, and changing this would 420 * probably upset a lot of people. 421 * 422 * Note that process 1 won't immediately exec init(8), but will 423 * wait for us to inform it that the root file system has been 424 * mounted. 425 */ 426 if (fork1(p, SIGCHLD, FORK_FORK, NULL, 0, start_init, NULL, NULL, 427 &initproc)) 428 panic("fork init"); 429 430 /* 431 * Create any kernel threads whose creation was deferred because 432 * initproc had not yet been created. 433 */ 434 kthread_run_deferred_queue(); 435 436 /* 437 * Now that device driver threads have been created, wait for 438 * them to finish any deferred autoconfiguration. Note we don't 439 * need to lock this semaphore, since we haven't booted any 440 * secondary processors, yet. 441 */ 442 while (config_pending) 443 (void) tsleep((void *)&config_pending, PWAIT, "cfpend", 0); 444 445 dostartuphooks(); 446 447 #if NVSCSI > 0 448 config_rootfound("vscsi", NULL); 449 #endif 450 #if NSOFTRAID > 0 451 config_rootfound("softraid", NULL); 452 #endif 453 454 /* Configure root/swap devices */ 455 diskconf(); 456 457 if (mountroot == NULL || ((*mountroot)() != 0)) 458 panic("cannot mount root"); 459 460 CIRCLEQ_FIRST(&mountlist)->mnt_flag |= MNT_ROOTFS; 461 462 /* Get the vnode for '/'. Set p->p_fd->fd_cdir to reference it. */ 463 if (VFS_ROOT(CIRCLEQ_FIRST(&mountlist), &rootvnode)) 464 panic("cannot find root vnode"); 465 p->p_fd->fd_cdir = rootvnode; 466 VREF(p->p_fd->fd_cdir); 467 VOP_UNLOCK(rootvnode, 0, p); 468 p->p_fd->fd_rdir = NULL; 469 470 /* 471 * Now that root is mounted, we can fixup initproc's CWD 472 * info. All other processes are kthreads, which merely 473 * share proc0's CWD info. 474 */ 475 initproc->p_fd->fd_cdir = rootvnode; 476 VREF(initproc->p_fd->fd_cdir); 477 initproc->p_fd->fd_rdir = NULL; 478 479 /* 480 * Now can look at time, having had a chance to verify the time 481 * from the file system. Reset p->p_rtime as it may have been 482 * munched in mi_switch() after the time got set. 483 */ 484 #ifdef __HAVE_TIMECOUNTER 485 microtime(&boottime); 486 #else 487 boottime = mono_time = time; 488 #endif 489 LIST_FOREACH(p, &allproc, p_list) { 490 p->p_stats->p_start = boottime; 491 microuptime(&p->p_cpu->ci_schedstate.spc_runtime); 492 p->p_rtime.tv_sec = p->p_rtime.tv_usec = 0; 493 } 494 495 uvm_swap_init(); 496 497 /* Create the pageout daemon kernel thread. */ 498 if (kthread_create(uvm_pageout, NULL, NULL, "pagedaemon")) 499 panic("fork pagedaemon"); 500 501 /* Create the reaper daemon kernel thread. */ 502 if (kthread_create(start_reaper, NULL, NULL, "reaper")) 503 panic("fork reaper"); 504 505 /* Create the cleaner daemon kernel thread. */ 506 if (kthread_create(start_cleaner, NULL, NULL, "cleaner")) 507 panic("fork cleaner"); 508 509 /* Create the update daemon kernel thread. */ 510 if (kthread_create(start_update, NULL, NULL, "update")) 511 panic("fork update"); 512 513 /* Create the aiodone daemon kernel thread. */ 514 if (kthread_create(uvm_aiodone_daemon, NULL, NULL, "aiodoned")) 515 panic("fork aiodoned"); 516 517 #ifdef CRYPTO 518 /* Create the crypto kernel thread. */ 519 init_crypto(); 520 #endif /* CRYPTO */ 521 522 microtime(&rtv); 523 srandom((u_int32_t)(rtv.tv_sec ^ rtv.tv_usec) ^ arc4random()); 524 525 randompid = 1; 526 527 #if defined(MULTIPROCESSOR) 528 /* Boot the secondary processors. */ 529 cpu_boot_secondary_processors(); 530 #endif 531 532 domountroothooks(); 533 534 /* 535 * Okay, now we can let init(8) exec! It's off to userland! 536 */ 537 start_init_exec = 1; 538 wakeup((void *)&start_init_exec); 539 540 /* The scheduler is an infinite loop. */ 541 uvm_scheduler(); 542 /* NOTREACHED */ 543 } 544 545 /* 546 * List of paths to try when searching for "init". 547 */ 548 static char *initpaths[] = { 549 "/sbin/init", 550 "/sbin/oinit", 551 "/sbin/init.bak", 552 NULL, 553 }; 554 555 void 556 check_console(struct proc *p) 557 { 558 struct nameidata nd; 559 int error; 560 561 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, "/dev/console", p); 562 error = namei(&nd); 563 if (error) { 564 if (error == ENOENT) 565 printf("warning: /dev/console does not exist\n"); 566 else 567 printf("warning: /dev/console error %d\n", error); 568 } else 569 vrele(nd.ni_vp); 570 } 571 572 /* 573 * Start the initial user process; try exec'ing each pathname in "initpaths". 574 * The program is invoked with one argument containing the boot flags. 575 */ 576 void 577 start_init(void *arg) 578 { 579 struct proc *p = arg; 580 vaddr_t addr; 581 struct sys_execve_args /* { 582 syscallarg(const char *) path; 583 syscallarg(char *const *) argp; 584 syscallarg(char *const *) envp; 585 } */ args; 586 int options, error; 587 long i; 588 register_t retval[2]; 589 char flags[4], *flagsp; 590 char **pathp, *path, *ucp, **uap, *arg0, *arg1 = NULL; 591 592 /* 593 * Now in process 1. 594 */ 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 check_console(p); 603 604 /* 605 * Need just enough stack to hold the faked-up "execve()" arguments. 606 */ 607 #ifdef MACHINE_STACK_GROWS_UP 608 addr = USRSTACK; 609 #else 610 addr = USRSTACK - PAGE_SIZE; 611 #endif 612 if (uvm_map(&p->p_vmspace->vm_map, &addr, PAGE_SIZE, 613 NULL, UVM_UNKNOWN_OFFSET, 0, 614 UVM_MAPFLAG(UVM_PROT_RW, UVM_PROT_ALL, UVM_INH_COPY, 615 UVM_ADV_NORMAL, UVM_FLAG_FIXED|UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW))) 616 panic("init: couldn't allocate argument space"); 617 p->p_vmspace->vm_maxsaddr = (caddr_t)addr; 618 619 for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) { 620 #ifdef MACHINE_STACK_GROWS_UP 621 ucp = (char *)addr; 622 #else 623 ucp = (char *)(addr + PAGE_SIZE); 624 #endif 625 /* 626 * Construct the boot flag argument. 627 */ 628 flagsp = flags; 629 *flagsp++ = '-'; 630 options = 0; 631 632 if (boothowto & RB_SINGLE) { 633 *flagsp++ = 's'; 634 options = 1; 635 } 636 #ifdef notyet 637 if (boothowto & RB_FASTBOOT) { 638 *flagsp++ = 'f'; 639 options = 1; 640 } 641 #endif 642 643 /* 644 * Move out the flags (arg 1), if necessary. 645 */ 646 if (options != 0) { 647 *flagsp++ = '\0'; 648 i = flagsp - flags; 649 #ifdef DEBUG 650 printf("init: copying out flags `%s' %d\n", flags, i); 651 #endif 652 #ifdef MACHINE_STACK_GROWS_UP 653 arg1 = ucp; 654 (void)copyout((caddr_t)flags, (caddr_t)ucp, i); 655 ucp += i; 656 #else 657 (void)copyout((caddr_t)flags, (caddr_t)(ucp -= i), i); 658 arg1 = ucp; 659 #endif 660 } 661 662 /* 663 * Move out the file name (also arg 0). 664 */ 665 i = strlen(path) + 1; 666 #ifdef DEBUG 667 printf("init: copying out path `%s' %d\n", path, i); 668 #endif 669 #ifdef MACHINE_STACK_GROWS_UP 670 arg0 = ucp; 671 (void)copyout((caddr_t)path, (caddr_t)ucp, i); 672 ucp += i; 673 ucp = (caddr_t)ALIGN((u_long)ucp); 674 uap = (char **)ucp + 3; 675 #else 676 (void)copyout((caddr_t)path, (caddr_t)(ucp -= i), i); 677 arg0 = ucp; 678 uap = (char **)((u_long)ucp & ~ALIGNBYTES); 679 #endif 680 681 /* 682 * Move out the arg pointers. 683 */ 684 i = 0; 685 copyout(&i, (caddr_t)--uap, sizeof(register_t)); /* terminator */ 686 if (options != 0) 687 copyout(&arg1, (caddr_t)--uap, sizeof(register_t)); 688 copyout(&arg0, (caddr_t)--uap, sizeof(register_t)); 689 690 /* 691 * Point at the arguments. 692 */ 693 SCARG(&args, path) = arg0; 694 SCARG(&args, argp) = uap; 695 SCARG(&args, envp) = NULL; 696 697 /* 698 * Now try to exec the program. If can't for any reason 699 * other than it doesn't exist, complain. 700 */ 701 if ((error = sys_execve(p, &args, retval)) == 0) { 702 KERNEL_PROC_UNLOCK(p); 703 return; 704 } 705 if (error != ENOENT) 706 printf("exec %s: error %d\n", path, error); 707 } 708 printf("init: not found\n"); 709 panic("no init"); 710 } 711 712 void 713 start_update(void *arg) 714 { 715 sched_sync(curproc); 716 /* NOTREACHED */ 717 } 718 719 void 720 start_cleaner(void *arg) 721 { 722 buf_daemon(curproc); 723 /* NOTREACHED */ 724 } 725 726 void 727 start_reaper(void *arg) 728 { 729 reaper(); 730 /* NOTREACHED */ 731 } 732