1 /*- 2 * Copyright (c) 1986, 1988, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. 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 * @(#)kern_shutdown.c 8.3 (Berkeley) 1/21/94 39 * $FreeBSD$ 40 */ 41 42 #include "opt_ddb.h" 43 #include "opt_ddb_trace.h" 44 #include "opt_ddb_unattended.h" 45 #include "opt_hw_wdog.h" 46 #include "opt_mac.h" 47 #include "opt_panic.h" 48 #include "opt_show_busybufs.h" 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/bio.h> 53 #include <sys/buf.h> 54 #include <sys/conf.h> 55 #include <sys/cons.h> 56 #include <sys/disklabel.h> 57 #include <sys/eventhandler.h> 58 #include <sys/kernel.h> 59 #include <sys/kthread.h> 60 #include <sys/mac.h> 61 #include <sys/malloc.h> 62 #include <sys/mount.h> 63 #include <sys/proc.h> 64 #include <sys/reboot.h> 65 #include <sys/resourcevar.h> 66 #include <sys/smp.h> /* smp_active */ 67 #include <sys/sysctl.h> 68 #include <sys/sysproto.h> 69 #include <sys/vnode.h> 70 71 #include <machine/pcb.h> 72 #include <machine/md_var.h> 73 #include <machine/smp.h> 74 75 #include <sys/signalvar.h> 76 #ifdef DDB 77 #include <ddb/ddb.h> 78 #endif 79 80 #ifndef PANIC_REBOOT_WAIT_TIME 81 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 82 #endif 83 84 /* 85 * Note that stdarg.h and the ANSI style va_start macro is used for both 86 * ANSI and traditional C compilers. 87 */ 88 #include <machine/stdarg.h> 89 90 #ifdef DDB 91 #ifdef DDB_UNATTENDED 92 int debugger_on_panic = 0; 93 #else 94 int debugger_on_panic = 1; 95 #endif 96 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 97 &debugger_on_panic, 0, "Run debugger on kernel panic"); 98 99 #ifdef DDB_TRACE 100 int trace_on_panic = 1; 101 #else 102 int trace_on_panic = 0; 103 #endif 104 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 105 &trace_on_panic, 0, "Print stack trace on kernel panic"); 106 #endif 107 108 int sync_on_panic = 1; 109 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 110 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 111 112 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 113 114 #ifdef HW_WDOG 115 /* 116 * If there is a hardware watchdog, point this at the function needed to 117 * hold it off. 118 * It's needed when the kernel needs to do some lengthy operations. 119 * e.g. in wd.c when dumping core.. It's most annoying to have 120 * your precious core-dump only half written because the wdog kicked in. 121 */ 122 watchdog_tickle_fn wdog_tickler = NULL; 123 #endif /* HW_WDOG */ 124 125 /* 126 * Variable panicstr contains argument to first call to panic; used as flag 127 * to indicate that the kernel has already called panic. 128 */ 129 const char *panicstr; 130 131 int dumping; /* system is dumping */ 132 static struct dumperinfo dumper; /* our selected dumper */ 133 static struct pcb dumppcb; /* "You Are Here" sign for dump-debuggers */ 134 135 static void boot(int) __dead2; 136 static void poweroff_wait(void *, int); 137 static void shutdown_halt(void *junk, int howto); 138 static void shutdown_panic(void *junk, int howto); 139 static void shutdown_reset(void *junk, int howto); 140 141 /* register various local shutdown events */ 142 static void 143 shutdown_conf(void *unused) 144 { 145 146 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 147 SHUTDOWN_PRI_FIRST); 148 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 149 SHUTDOWN_PRI_LAST + 100); 150 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 151 SHUTDOWN_PRI_LAST + 100); 152 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 153 SHUTDOWN_PRI_LAST + 200); 154 } 155 156 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 157 158 /* 159 * The system call that results in a reboot 160 * 161 * MPSAFE 162 */ 163 /* ARGSUSED */ 164 int 165 reboot(struct thread *td, struct reboot_args *uap) 166 { 167 int error; 168 169 error = 0; 170 #ifdef MAC 171 error = mac_check_system_reboot(td->td_ucred, uap->opt); 172 #endif 173 if (error == 0) 174 error = suser(td); 175 if (error == 0) { 176 mtx_lock(&Giant); 177 boot(uap->opt); 178 mtx_unlock(&Giant); 179 } 180 return (error); 181 } 182 183 /* 184 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 185 */ 186 static int shutdown_howto = 0; 187 188 void 189 shutdown_nice(int howto) 190 { 191 192 shutdown_howto = howto; 193 194 /* Send a signal to init(8) and have it shutdown the world */ 195 if (initproc != NULL) { 196 PROC_LOCK(initproc); 197 psignal(initproc, SIGINT); 198 PROC_UNLOCK(initproc); 199 } else { 200 /* No init(8) running, so simply reboot */ 201 boot(RB_NOSYNC); 202 } 203 return; 204 } 205 static int waittime = -1; 206 207 static void 208 print_uptime(void) 209 { 210 int f; 211 struct timespec ts; 212 213 getnanouptime(&ts); 214 printf("Uptime: "); 215 f = 0; 216 if (ts.tv_sec >= 86400) { 217 printf("%ldd", (long)ts.tv_sec / 86400); 218 ts.tv_sec %= 86400; 219 f = 1; 220 } 221 if (f || ts.tv_sec >= 3600) { 222 printf("%ldh", (long)ts.tv_sec / 3600); 223 ts.tv_sec %= 3600; 224 f = 1; 225 } 226 if (f || ts.tv_sec >= 60) { 227 printf("%ldm", (long)ts.tv_sec / 60); 228 ts.tv_sec %= 60; 229 f = 1; 230 } 231 printf("%lds\n", (long)ts.tv_sec); 232 } 233 234 static void 235 doadump(void) 236 { 237 238 savectx(&dumppcb); 239 dumping++; 240 dumpsys(&dumper); 241 } 242 243 /* 244 * Go through the rigmarole of shutting down.. 245 * this used to be in machdep.c but I'll be dammned if I could see 246 * anything machine dependant in it. 247 */ 248 static void 249 boot(int howto) 250 { 251 252 /* collect extra flags that shutdown_nice might have set */ 253 howto |= shutdown_howto; 254 255 #ifdef DDB 256 /* We are out of the debugger now. */ 257 db_active = 0; 258 #endif 259 260 #ifdef SMP 261 if (smp_active) 262 printf("boot() called on cpu#%d\n", PCPU_GET(cpuid)); 263 #endif 264 /* 265 * Do any callouts that should be done BEFORE syncing the filesystems. 266 */ 267 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 268 269 /* 270 * Now sync filesystems 271 */ 272 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 273 register struct buf *bp; 274 int iter, nbusy, pbusy; 275 int subiter; 276 277 waittime = 0; 278 printf("\nsyncing disks, buffers remaining... "); 279 280 sync(&thread0, NULL); 281 282 /* 283 * With soft updates, some buffers that are 284 * written will be remarked as dirty until other 285 * buffers are written. 286 */ 287 for (iter = pbusy = 0; iter < 20; iter++) { 288 nbusy = 0; 289 for (bp = &buf[nbuf]; --bp >= buf; ) { 290 if ((bp->b_flags & B_INVAL) == 0 && 291 BUF_REFCNT(bp) > 0) { 292 nbusy++; 293 } else if ((bp->b_flags & (B_DELWRI | B_INVAL)) 294 == B_DELWRI) { 295 /* bawrite(bp);*/ 296 nbusy++; 297 } 298 } 299 if (nbusy == 0) 300 break; 301 printf("%d ", nbusy); 302 if (nbusy < pbusy) 303 iter = 0; 304 pbusy = nbusy; 305 sync(&thread0, NULL); 306 if (curthread != NULL) { 307 DROP_GIANT(); 308 for (subiter = 0; subiter < 50 * iter; subiter++) { 309 mtx_lock_spin(&sched_lock); 310 curthread->td_proc->p_stats->p_ru.ru_nvcsw++; 311 mi_switch(); /* Allow interrupt threads to run */ 312 mtx_unlock_spin(&sched_lock); 313 DELAY(1000); 314 } 315 PICKUP_GIANT(); 316 } else 317 DELAY(50000 * iter); 318 } 319 printf("\n"); 320 /* 321 * Count only busy local buffers to prevent forcing 322 * a fsck if we're just a client of a wedged NFS server 323 */ 324 nbusy = 0; 325 for (bp = &buf[nbuf]; --bp >= buf; ) { 326 if (((bp->b_flags&B_INVAL) == 0 && BUF_REFCNT(bp)) || 327 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 328 if (bp->b_dev == NODEV) { 329 TAILQ_REMOVE(&mountlist, 330 bp->b_vp->v_mount, mnt_list); 331 continue; 332 } 333 nbusy++; 334 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 335 printf( 336 "%d: dev:%s, flags:%0x, blkno:%ld, lblkno:%ld\n", 337 nbusy, devtoname(bp->b_dev), 338 bp->b_flags, (long)bp->b_blkno, 339 (long)bp->b_lblkno); 340 #endif 341 } 342 } 343 if (nbusy) { 344 /* 345 * Failed to sync all blocks. Indicate this and don't 346 * unmount filesystems (thus forcing an fsck on reboot). 347 */ 348 printf("giving up on %d buffers\n", nbusy); 349 DELAY(5000000); /* 5 seconds */ 350 } else { 351 printf("done\n"); 352 /* 353 * Unmount filesystems 354 */ 355 if (panicstr == 0) 356 vfs_unmountall(); 357 } 358 DELAY(100000); /* wait for console output to finish */ 359 } 360 361 print_uptime(); 362 363 /* 364 * Ok, now do things that assume all filesystem activity has 365 * been completed. 366 */ 367 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 368 splhigh(); 369 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && 370 !cold && dumper.dumper != NULL && !dumping) 371 doadump(); 372 373 /* Now that we're going to really halt the system... */ 374 EVENTHANDLER_INVOKE(shutdown_final, howto); 375 376 for(;;) ; /* safety against shutdown_reset not working */ 377 /* NOTREACHED */ 378 } 379 380 /* 381 * If the shutdown was a clean halt, behave accordingly. 382 */ 383 static void 384 shutdown_halt(void *junk, int howto) 385 { 386 387 if (howto & RB_HALT) { 388 printf("\n"); 389 printf("The operating system has halted.\n"); 390 printf("Please press any key to reboot.\n\n"); 391 switch (cngetc()) { 392 case -1: /* No console, just die */ 393 cpu_halt(); 394 /* NOTREACHED */ 395 default: 396 howto &= ~RB_HALT; 397 break; 398 } 399 } 400 } 401 402 /* 403 * Check to see if the system paniced, pause and then reboot 404 * according to the specified delay. 405 */ 406 static void 407 shutdown_panic(void *junk, int howto) 408 { 409 int loop; 410 411 if (howto & RB_DUMP) { 412 if (PANIC_REBOOT_WAIT_TIME != 0) { 413 if (PANIC_REBOOT_WAIT_TIME != -1) { 414 printf("Automatic reboot in %d seconds - " 415 "press a key on the console to abort\n", 416 PANIC_REBOOT_WAIT_TIME); 417 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 418 loop > 0; --loop) { 419 DELAY(1000 * 100); /* 1/10th second */ 420 /* Did user type a key? */ 421 if (cncheckc() != -1) 422 break; 423 } 424 if (!loop) 425 return; 426 } 427 } else { /* zero time specified - reboot NOW */ 428 return; 429 } 430 printf("--> Press a key on the console to reboot,\n"); 431 printf("--> or switch off the system now.\n"); 432 cngetc(); 433 } 434 } 435 436 /* 437 * Everything done, now reset 438 */ 439 static void 440 shutdown_reset(void *junk, int howto) 441 { 442 443 printf("Rebooting...\n"); 444 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 445 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 446 cpu_reset(); 447 /* NOTREACHED */ /* assuming reset worked */ 448 } 449 450 /* 451 * Print a backtrace if we can. 452 */ 453 454 void 455 backtrace(void) 456 { 457 458 #ifdef DDB 459 printf("Stack backtrace:\n"); 460 db_print_backtrace(); 461 #else 462 printf("Sorry, need DDB option to print backtrace"); 463 #endif 464 } 465 466 #ifdef SMP 467 static u_int panic_cpu = NOCPU; 468 #endif 469 470 /* 471 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 472 * and then reboots. If we are called twice, then we avoid trying to sync 473 * the disks as this often leads to recursive panics. 474 * 475 * MPSAFE 476 */ 477 void 478 panic(const char *fmt, ...) 479 { 480 struct thread *td = curthread; 481 int bootopt, newpanic; 482 va_list ap; 483 static char buf[256]; 484 485 #ifdef SMP 486 /* 487 * We don't want multiple CPU's to panic at the same time, so we 488 * use panic_cpu as a simple spinlock. We have to keep checking 489 * panic_cpu if we are spinning in case the panic on the first 490 * CPU is canceled. 491 */ 492 if (panic_cpu != PCPU_GET(cpuid)) 493 while (atomic_cmpset_int(&panic_cpu, NOCPU, 494 PCPU_GET(cpuid)) == 0) 495 while (panic_cpu != NOCPU) 496 ; /* nothing */ 497 #endif 498 499 bootopt = RB_AUTOBOOT | RB_DUMP; 500 newpanic = 0; 501 if (panicstr) 502 bootopt |= RB_NOSYNC; 503 else { 504 panicstr = fmt; 505 newpanic = 1; 506 } 507 508 va_start(ap, fmt); 509 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 510 if (panicstr == fmt) 511 panicstr = buf; 512 va_end(ap); 513 printf("panic: %s\n", buf); 514 #ifdef SMP 515 /* two separate prints in case of an unmapped page and trap */ 516 printf("cpuid = %d; ", PCPU_GET(cpuid)); 517 #ifdef APIC_IO 518 printf("lapic.id = %08x\n", lapic.id); 519 #else 520 printf("\n"); 521 #endif 522 #endif 523 524 #if defined(DDB) 525 if (newpanic && trace_on_panic) 526 backtrace(); 527 if (debugger_on_panic) 528 Debugger ("panic"); 529 #ifdef RESTARTABLE_PANICS 530 /* See if the user aborted the panic, in which case we continue. */ 531 if (panicstr == NULL) { 532 #ifdef SMP 533 atomic_store_rel_int(&panic_cpu, NOCPU); 534 #endif 535 return; 536 } 537 #endif 538 #endif 539 td->td_flags |= TDF_INPANIC; 540 if (!sync_on_panic) 541 bootopt |= RB_NOSYNC; 542 boot(bootopt); 543 } 544 545 /* 546 * Support for poweroff delay. 547 */ 548 #ifndef POWEROFF_DELAY 549 # define POWEROFF_DELAY 5000 550 #endif 551 static int poweroff_delay = POWEROFF_DELAY; 552 553 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 554 &poweroff_delay, 0, ""); 555 556 static void 557 poweroff_wait(void *junk, int howto) 558 { 559 560 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 561 return; 562 DELAY(poweroff_delay * 1000); 563 } 564 565 /* 566 * Some system processes (e.g. syncer) need to be stopped at appropriate 567 * points in their main loops prior to a system shutdown, so that they 568 * won't interfere with the shutdown process (e.g. by holding a disk buf 569 * to cause sync to fail). For each of these system processes, register 570 * shutdown_kproc() as a handler for one of shutdown events. 571 */ 572 static int kproc_shutdown_wait = 60; 573 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 574 &kproc_shutdown_wait, 0, ""); 575 576 void 577 kproc_shutdown(void *arg, int howto) 578 { 579 struct proc *p; 580 int error; 581 582 if (panicstr) 583 return; 584 585 p = (struct proc *)arg; 586 printf("Waiting (max %d seconds) for system process `%s' to stop...", 587 kproc_shutdown_wait, p->p_comm); 588 error = kthread_suspend(p, kproc_shutdown_wait * hz); 589 590 if (error == EWOULDBLOCK) 591 printf("timed out\n"); 592 else 593 printf("stopped\n"); 594 } 595 596 /* Registration of dumpers */ 597 int 598 set_dumper(struct dumperinfo *di) 599 { 600 601 if (di == NULL) { 602 bzero(&dumper, sizeof dumper); 603 return (0); 604 } 605 if (dumper.dumper != NULL) 606 return (EBUSY); 607 dumper = *di; 608 return (0); 609 } 610 611 #if defined(__powerpc__) 612 void 613 dumpsys(struct dumperinfo *di __unused) 614 { 615 616 printf("Kernel dumps not implemented on this architecture\n"); 617 } 618 #endif 619