1 /* 2 * Copyright (c) 1995 Terrence R. Lambert 3 * All rights reserved. 4 * 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 8.9 (Berkeley) 1/21/94 42 * $Id: init_main.c,v 1.102 1998/12/30 10:38:58 dfr Exp $ 43 */ 44 45 #include "opt_devfs.h" 46 47 #include <sys/param.h> 48 #include <sys/file.h> 49 #include <sys/filedesc.h> 50 #include <sys/kernel.h> 51 #include <sys/mount.h> 52 #include <sys/sysctl.h> 53 #include <sys/proc.h> 54 #include <sys/resourcevar.h> 55 #include <sys/signalvar.h> 56 #include <sys/systm.h> 57 #include <sys/vnode.h> 58 #include <sys/sysent.h> 59 #include <sys/reboot.h> 60 #include <sys/sysproto.h> 61 #include <sys/vmmeter.h> 62 #include <sys/unistd.h> 63 #include <sys/malloc.h> 64 65 #include <machine/cpu.h> 66 67 #include <vm/vm.h> 68 #include <vm/vm_param.h> 69 #include <vm/vm_prot.h> 70 #include <sys/lock.h> 71 #include <vm/pmap.h> 72 #include <vm/vm_map.h> 73 #include <sys/user.h> 74 #include <sys/copyright.h> 75 76 extern struct linker_set sysinit_set; /* XXX */ 77 78 extern void __main __P((void)); 79 extern void main __P((void *framep)); 80 81 /* Components of the first process -- never freed. */ 82 static struct session session0; 83 static struct pgrp pgrp0; 84 struct proc proc0; 85 static struct pcred cred0; 86 #ifdef COMPAT_LINUX_THREADS 87 static struct procsig procsig0; 88 #endif /* COMPAT_LINUX_THREADS */ 89 static struct filedesc0 filedesc0; 90 static struct plimit limit0; 91 static struct vmspace vmspace0; 92 struct proc *initproc; 93 94 int cmask = CMASK; 95 extern struct user *proc0paddr; 96 97 struct vnode *rootvp; 98 int boothowto = 0; /* initialized so that it can be patched */ 99 100 struct timeval boottime; 101 SYSCTL_STRUCT(_kern, KERN_BOOTTIME, boottime, 102 CTLFLAG_RD, &boottime, timeval, ""); 103 104 static int shutdowntimeout = 120; 105 SYSCTL_INT(_kern, OID_AUTO, shutdown_timeout, 106 CTLFLAG_RW, &shutdowntimeout, 0, ""); 107 108 /* 109 * Promiscuous argument pass for start_init() 110 * 111 * This is a kludge because we use a return from main() rather than a call 112 * to a new routine in locore.s to kick the kernel alive from locore.s. 113 */ 114 static void *init_framep; 115 116 117 #if __GNUC__ >= 2 118 void __main() {} 119 #endif 120 121 122 /* 123 * This ensures that there is at least one entry so that the sysinit_set 124 * symbol is not undefined. A sybsystem ID of SI_SUB_DUMMY is never 125 * executed. 126 */ 127 SYSINIT(placeholder, SI_SUB_DUMMY,SI_ORDER_ANY, NULL, NULL) 128 129 /* 130 * The sysinit table itself. Items are checked off as the are run. 131 * If we want to register new sysinit types, add them to newsysinit. 132 */ 133 struct sysinit **sysinit = (struct sysinit **)sysinit_set.ls_items; 134 struct sysinit **newsysinit; 135 136 /* 137 * Merge a new sysinit set into the current set, reallocating it if 138 * necessary. This can only be called after malloc is running. 139 */ 140 void 141 sysinit_add(set) 142 struct sysinit **set; 143 { 144 struct sysinit **newset; 145 struct sysinit **sipp; 146 struct sysinit **xipp; 147 int count = 0; 148 149 if (newsysinit) 150 for (sipp = newsysinit; *sipp; sipp++) 151 count++; 152 else 153 for (sipp = sysinit; *sipp; sipp++) 154 count++; 155 for (sipp = set; *sipp; sipp++) 156 count++; 157 count++; /* Trailing NULL */ 158 newset = malloc(count * sizeof(*sipp), M_TEMP, M_NOWAIT); 159 if (newset == NULL) 160 panic("cannot malloc for sysinit"); 161 xipp = newset; 162 if (newsysinit) 163 for (sipp = newsysinit; *sipp; sipp++) 164 *xipp++ = *sipp; 165 else 166 for (sipp = sysinit; *sipp; sipp++) 167 *xipp++ = *sipp; 168 for (sipp = set; *sipp; sipp++) 169 *xipp++ = *sipp; 170 *xipp = NULL; 171 if (newsysinit) 172 free(newsysinit, M_TEMP); 173 newsysinit = newset; 174 } 175 176 /* 177 * System startup; initialize the world, create process 0, mount root 178 * filesystem, and fork to create init and pagedaemon. Most of the 179 * hard work is done in the lower-level initialization routines including 180 * startup(), which does memory initialization and autoconfiguration. 181 * 182 * This allows simple addition of new kernel subsystems that require 183 * boot time initialization. It also allows substitution of subsystem 184 * (for instance, a scheduler, kernel profiler, or VM system) by object 185 * module. Finally, it allows for optional "kernel threads". 186 */ 187 void 188 main(framep) 189 void *framep; 190 { 191 192 register struct sysinit **sipp; /* system initialization*/ 193 register struct sysinit **xipp; /* interior loop of sort*/ 194 register struct sysinit *save; /* bubble*/ 195 196 /* 197 * Copy the locore.s frame pointer for proc0, this is forked into 198 * all other processes. 199 */ 200 init_framep = framep; 201 202 restart: 203 /* 204 * Perform a bubble sort of the system initialization objects by 205 * their subsystem (primary key) and order (secondary key). 206 */ 207 for (sipp = sysinit; *sipp; sipp++) { 208 for (xipp = sipp + 1; *xipp; xipp++) { 209 if ((*sipp)->subsystem < (*xipp)->subsystem || 210 ((*sipp)->subsystem == (*xipp)->subsystem && 211 (*sipp)->order < (*xipp)->order)) 212 continue; /* skip*/ 213 save = *sipp; 214 *sipp = *xipp; 215 *xipp = save; 216 } 217 } 218 219 /* 220 * Traverse the (now) ordered list of system initialization tasks. 221 * Perform each task, and continue on to the next task. 222 * 223 * The last item on the list is expected to be the scheduler, 224 * which will not return. 225 */ 226 for (sipp = sysinit; *sipp; sipp++) { 227 228 if ((*sipp)->subsystem == SI_SUB_DUMMY) 229 continue; /* skip dummy task(s)*/ 230 231 if ((*sipp)->subsystem == SI_SUB_DONE) 232 continue; 233 234 switch( (*sipp)->type) { 235 case SI_TYPE_DEFAULT: 236 /* no special processing*/ 237 (*((*sipp)->func))((*sipp)->udata); 238 break; 239 240 case SI_TYPE_KTHREAD: 241 #if !defined(SMP) 242 /* kernel thread*/ 243 if (fork1(&proc0, RFMEM|RFFDG|RFPROC)) 244 panic("fork kernel thread"); 245 cpu_set_fork_handler(pfind(proc0.p_retval[0]), 246 (*sipp)->func, (*sipp)->udata); 247 break; 248 #endif 249 250 case SI_TYPE_KPROCESS: 251 if (fork1(&proc0, RFFDG|RFPROC)) 252 panic("fork kernel process"); 253 cpu_set_fork_handler(pfind(proc0.p_retval[0]), 254 (*sipp)->func, (*sipp)->udata); 255 break; 256 257 default: 258 panic("init_main: unrecognized init type"); 259 } 260 261 /* Check off the one we're just done */ 262 (*sipp)->subsystem = SI_SUB_DONE; 263 264 /* Check if we've installed more sysinit items via KLD */ 265 if (newsysinit != NULL) { 266 if (sysinit != (struct sysinit **)sysinit_set.ls_items) 267 free(sysinit, M_TEMP); 268 sysinit = newsysinit; 269 newsysinit = NULL; 270 goto restart; 271 } 272 } 273 274 panic("Shouldn't get here!"); 275 /* NOTREACHED*/ 276 } 277 278 279 /* 280 * Start a kernel process. This is called after a fork() call in 281 * main() in the file kern/init_main.c. 282 * 283 * This function is used to start "internal" daemons. 284 */ 285 /* ARGSUSED*/ 286 void 287 kproc_start(udata) 288 void *udata; 289 { 290 struct kproc_desc *kp = udata; 291 struct proc *p = curproc; 292 293 #ifdef DIAGNOSTIC 294 printf("Start pid=%d <%s>\n",p->p_pid, kp->arg0); 295 #endif 296 297 /* save a global descriptor, if desired*/ 298 if( kp->global_procpp != NULL) 299 *kp->global_procpp = p; 300 301 /* this is a non-swapped system process*/ 302 p->p_flag |= P_INMEM | P_SYSTEM; 303 304 /* set up arg0 for 'ps', et al*/ 305 strcpy( p->p_comm, kp->arg0); 306 307 /* call the processes' main()...*/ 308 (*kp->func)(); 309 310 /* NOTREACHED */ 311 panic("kproc_start: %s", kp->arg0); 312 } 313 314 315 /* 316 *************************************************************************** 317 **** 318 **** The following SYSINIT's belong elsewhere, but have not yet 319 **** been moved. 320 **** 321 *************************************************************************** 322 */ 323 #ifdef OMIT 324 /* 325 * Handled by vfs_mountroot (bad idea) at this time... should be 326 * done the same as 4.4Lite2. 327 */ 328 SYSINIT(swapinit, SI_SUB_SWAP, SI_ORDER_FIRST, swapinit, NULL) 329 #endif /* OMIT*/ 330 331 static void print_caddr_t __P((void *data)); 332 static void 333 print_caddr_t(data) 334 void *data; 335 { 336 printf("%s", (char *)data); 337 } 338 SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t, copyright) 339 340 341 /* 342 *************************************************************************** 343 **** 344 **** The two following SYSINT's are proc0 specific glue code. I am not 345 **** convinced that they can not be safely combined, but their order of 346 **** operation has been maintained as the same as the original init_main.c 347 **** for right now. 348 **** 349 **** These probably belong in init_proc.c or kern_proc.c, since they 350 **** deal with proc0 (the fork template process). 351 **** 352 *************************************************************************** 353 */ 354 /* ARGSUSED*/ 355 static void proc0_init __P((void *dummy)); 356 static void 357 proc0_init(dummy) 358 void *dummy; 359 { 360 register struct proc *p; 361 register struct filedesc0 *fdp; 362 register unsigned i; 363 364 /* 365 * Initialize the current process pointer (curproc) before 366 * any possible traps/probes to simplify trap processing. 367 */ 368 p = &proc0; 369 curproc = p; /* XXX redundant*/ 370 371 /* 372 * Initialize process and pgrp structures. 373 */ 374 procinit(); 375 376 /* 377 * Initialize sleep queue hash table 378 */ 379 sleepinit(); 380 381 /* 382 * additional VM structures 383 */ 384 vm_init2(); 385 386 /* 387 * Create process 0 (the swapper). 388 */ 389 LIST_INSERT_HEAD(&allproc, p, p_list); 390 p->p_pgrp = &pgrp0; 391 LIST_INSERT_HEAD(PGRPHASH(0), &pgrp0, pg_hash); 392 LIST_INIT(&pgrp0.pg_members); 393 LIST_INSERT_HEAD(&pgrp0.pg_members, p, p_pglist); 394 395 pgrp0.pg_session = &session0; 396 session0.s_count = 1; 397 session0.s_leader = p; 398 399 p->p_sysent = &aout_sysvec; 400 401 p->p_flag = P_INMEM | P_SYSTEM; 402 p->p_stat = SRUN; 403 p->p_nice = NZERO; 404 p->p_rtprio.type = RTP_PRIO_NORMAL; 405 p->p_rtprio.prio = 0; 406 407 /* 408 * Link for kernel based threads 409 */ 410 p->p_peers = 0; 411 p->p_leader = p; 412 413 bcopy("swapper", p->p_comm, sizeof ("swapper")); 414 415 /* Create credentials. */ 416 cred0.p_refcnt = 1; 417 p->p_cred = &cred0; 418 p->p_ucred = crget(); 419 p->p_ucred->cr_ngroups = 1; /* group 0 */ 420 421 #ifdef COMPAT_LINUX_THREADS 422 /* Create procsig. */ 423 p->p_procsig = &procsig0; 424 p->p_procsig->ps_refcnt = 2; 425 426 #endif /* COMPAT_LINUX_THREADS */ 427 /* Create the file descriptor table. */ 428 fdp = &filedesc0; 429 p->p_fd = &fdp->fd_fd; 430 fdp->fd_fd.fd_refcnt = 1; 431 fdp->fd_fd.fd_cmask = cmask; 432 fdp->fd_fd.fd_ofiles = fdp->fd_dfiles; 433 fdp->fd_fd.fd_ofileflags = fdp->fd_dfileflags; 434 fdp->fd_fd.fd_nfiles = NDFILE; 435 436 /* Create the limits structures. */ 437 p->p_limit = &limit0; 438 for (i = 0; i < sizeof(p->p_rlimit)/sizeof(p->p_rlimit[0]); i++) 439 limit0.pl_rlimit[i].rlim_cur = 440 limit0.pl_rlimit[i].rlim_max = RLIM_INFINITY; 441 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_cur = 442 limit0.pl_rlimit[RLIMIT_NOFILE].rlim_max = maxfiles; 443 limit0.pl_rlimit[RLIMIT_NPROC].rlim_cur = 444 limit0.pl_rlimit[RLIMIT_NPROC].rlim_max = maxproc; 445 i = ptoa(cnt.v_free_count); 446 limit0.pl_rlimit[RLIMIT_RSS].rlim_max = i; 447 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_max = i; 448 limit0.pl_rlimit[RLIMIT_MEMLOCK].rlim_cur = i / 3; 449 limit0.p_cpulimit = RLIM_INFINITY; 450 limit0.p_refcnt = 1; 451 452 453 /* Allocate a prototype map so we have something to fork. */ 454 pmap_pinit0(&vmspace0.vm_pmap); 455 p->p_vmspace = &vmspace0; 456 vmspace0.vm_refcnt = 1; 457 vm_map_init(&vmspace0.vm_map, round_page(VM_MIN_ADDRESS), 458 trunc_page(VM_MAXUSER_ADDRESS)); 459 vmspace0.vm_map.pmap = &vmspace0.vm_pmap; 460 p->p_addr = proc0paddr; /* XXX */ 461 462 #ifndef __alpha__ /* XXX what is this? */ 463 #define INCOMPAT_LITES2 464 #ifdef INCOMPAT_LITES2 465 /* 466 * proc0 needs to have a coherent frame base in its stack. 467 */ 468 cpu_set_init_frame(p, init_framep); /* XXX! */ 469 #endif /* INCOMPAT_LITES2*/ 470 #endif 471 472 /* 473 * We continue to place resource usage info and signal 474 * actions in the user struct so they're pageable. 475 */ 476 p->p_stats = &p->p_addr->u_stats; 477 p->p_sigacts = &p->p_addr->u_sigacts; 478 479 /* 480 * Charge root for one process. 481 */ 482 (void)chgproccnt(0, 1); 483 484 /* 485 * Initialize the procfs flags (to 0, of course) 486 */ 487 p->p_stops = p->p_stype = p->p_step = 0; 488 489 } 490 SYSINIT(p0init, SI_SUB_INTRINSIC, SI_ORDER_FIRST, proc0_init, NULL) 491 492 /* ARGSUSED*/ 493 static void proc0_post __P((void *dummy)); 494 static void 495 proc0_post(dummy) 496 void *dummy; 497 { 498 struct timespec ts; 499 500 /* 501 * Now can look at time, having had a chance to verify the time 502 * from the file system. Reset p->p_runtime as it may have been 503 * munched in mi_switch() after the time got set. Set 504 * p->p_switchtime to be consistent with this unmunching. 505 */ 506 microtime(&proc0.p_stats->p_start); 507 proc0.p_runtime = 0; 508 microuptime(&proc0.p_switchtime); 509 510 /* 511 * Give the ``random'' number generator a thump. 512 * XXX: Does read_random() contain enough bits to be used here ? 513 */ 514 nanotime(&ts); 515 srandom(ts.tv_sec ^ ts.tv_nsec); 516 517 /* Initialize signal state for process 0. */ 518 siginit(&proc0); 519 } 520 SYSINIT(p0post, SI_SUB_INTRINSIC_POST, SI_ORDER_FIRST, proc0_post, NULL) 521 522 523 524 525 /* 526 *************************************************************************** 527 **** 528 **** The following SYSINIT's and glue code should be moved to the 529 **** respective files on a per subsystem basis. 530 **** 531 *************************************************************************** 532 */ 533 534 /* ARGSUSED */ 535 static void root_conf __P((void *dummy)); 536 static void 537 root_conf(dummy) 538 void *dummy; 539 { 540 cpu_rootconf(); 541 } 542 SYSINIT(root_conf, SI_SUB_ROOT_CONF, SI_ORDER_FIRST, root_conf, NULL) 543 544 /* ARGSUSED*/ 545 static void xxx_vfs_root_fdtab __P((void *dummy)); 546 static void 547 xxx_vfs_root_fdtab(dummy) 548 void *dummy; 549 { 550 register struct filedesc0 *fdp = &filedesc0; 551 552 /* Get the vnode for '/'. Set fdp->fd_fd.fd_cdir to reference it. */ 553 if (VFS_ROOT(mountlist.cqh_first, &rootvnode)) 554 panic("cannot find root vnode"); 555 fdp->fd_fd.fd_cdir = rootvnode; 556 VREF(fdp->fd_fd.fd_cdir); 557 VOP_UNLOCK(rootvnode, 0, &proc0); 558 fdp->fd_fd.fd_rdir = rootvnode; 559 } 560 SYSINIT(retrofit, SI_SUB_ROOT_FDTAB, SI_ORDER_FIRST, xxx_vfs_root_fdtab, NULL) 561 562 563 /* 564 *************************************************************************** 565 **** 566 **** The following code probably belongs in another file, like 567 **** kern/init_init.c. It is here for two reasons only: 568 **** 569 **** 1) This code returns to startup the system; this is 570 **** abnormal for a kernel thread. 571 **** 2) This code promiscuously uses init_frame 572 **** 573 *************************************************************************** 574 */ 575 576 static void kthread_init __P((void *dummy)); 577 SYSINIT_KP(init,SI_SUB_KTHREAD_INIT, SI_ORDER_FIRST, kthread_init, NULL) 578 579 580 extern void prepare_usermode __P((void)); 581 static void start_init __P((struct proc *p)); 582 583 /* ARGSUSED*/ 584 static void 585 kthread_init(dummy) 586 void *dummy; 587 { 588 /* Create process 1 (init(8)). */ 589 start_init(curproc); 590 591 prepare_usermode(); 592 593 /* 594 * This returns to the fork trampoline, then to user mode. 595 */ 596 return; 597 } 598 599 600 /* 601 * List of paths to try when searching for "init". 602 */ 603 static char *initpaths[] = { 604 "/sbin/init", 605 "/sbin/oinit", 606 "/sbin/init.bak", 607 "/stand/sysinstall", 608 NULL, 609 }; 610 611 /* 612 * Start the initial user process; try exec'ing each pathname in "initpaths". 613 * The program is invoked with one argument containing the boot flags. 614 */ 615 static void 616 start_init(p) 617 struct proc *p; 618 { 619 vm_offset_t addr; 620 struct execve_args args; 621 int options, i, error; 622 char **pathp, *path, *ucp, **uap, *arg0, *arg1; 623 624 initproc = p; 625 626 /* 627 * Need just enough stack to hold the faked-up "execve()" arguments. 628 */ 629 addr = trunc_page(USRSTACK - PAGE_SIZE); 630 if (vm_map_find(&p->p_vmspace->vm_map, NULL, 0, &addr, PAGE_SIZE, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0) != 0) 631 panic("init: couldn't allocate argument space"); 632 p->p_vmspace->vm_maxsaddr = (caddr_t)addr; 633 p->p_vmspace->vm_ssize = 1; 634 635 for (pathp = &initpaths[0]; (path = *pathp) != NULL; pathp++) { 636 /* 637 * Move out the boot flag argument. 638 */ 639 options = 0; 640 ucp = (char *)USRSTACK; 641 (void)subyte(--ucp, 0); /* trailing zero */ 642 if (boothowto & RB_SINGLE) { 643 (void)subyte(--ucp, 's'); 644 options = 1; 645 } 646 #ifdef notyet 647 if (boothowto & RB_FASTBOOT) { 648 (void)subyte(--ucp, 'f'); 649 options = 1; 650 } 651 #endif 652 653 #ifdef BOOTCDROM 654 (void)subyte(--ucp, 'C'); 655 options = 1; 656 #endif 657 if (options == 0) 658 (void)subyte(--ucp, '-'); 659 (void)subyte(--ucp, '-'); /* leading hyphen */ 660 arg1 = ucp; 661 662 /* 663 * Move out the file name (also arg 0). 664 */ 665 for (i = strlen(path) + 1; i >= 0; i--) 666 (void)subyte(--ucp, path[i]); 667 arg0 = ucp; 668 669 /* 670 * Move out the arg pointers. 671 */ 672 uap = (char **)((intptr_t)ucp & ~(sizeof(intptr_t)-1)); 673 (void)suword((caddr_t)--uap, (long)0); /* terminator */ 674 (void)suword((caddr_t)--uap, (long)(intptr_t)arg1); 675 (void)suword((caddr_t)--uap, (long)(intptr_t)arg0); 676 677 /* 678 * Point at the arguments. 679 */ 680 args.fname = arg0; 681 args.argv = uap; 682 args.envv = NULL; 683 684 /* 685 * Now try to exec the program. If can't for any reason 686 * other than it doesn't exist, complain. 687 * 688 * Otherwise return to main() which returns to btext 689 * which completes the system startup. 690 */ 691 if ((error = execve(p, &args)) == 0) 692 return; 693 if (error != ENOENT) 694 printf("exec %s: error %d\n", path, error); 695 } 696 printf("init: not found\n"); 697 panic("no init"); 698 } 699