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 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)kern_shutdown.c 8.3 (Berkeley) 1/21/94 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_kdb.h" 41 #include "opt_hw_wdog.h" 42 #include "opt_mac.h" 43 #include "opt_panic.h" 44 #include "opt_show_busybufs.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/bio.h> 49 #include <sys/buf.h> 50 #include <sys/conf.h> 51 #include <sys/cons.h> 52 #include <sys/eventhandler.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/kthread.h> 56 #include <sys/mac.h> 57 #include <sys/malloc.h> 58 #include <sys/mount.h> 59 #include <sys/proc.h> 60 #include <sys/reboot.h> 61 #include <sys/resourcevar.h> 62 #include <sys/smp.h> /* smp_active */ 63 #include <sys/sysctl.h> 64 #include <sys/sysproto.h> 65 #include <sys/vnode.h> 66 67 #include <machine/cpu.h> 68 #include <machine/pcb.h> 69 #include <machine/smp.h> 70 71 #include <sys/signalvar.h> 72 73 #ifndef PANIC_REBOOT_WAIT_TIME 74 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 75 #endif 76 77 /* 78 * Note that stdarg.h and the ANSI style va_start macro is used for both 79 * ANSI and traditional C compilers. 80 */ 81 #include <machine/stdarg.h> 82 83 #ifdef KDB 84 #ifdef KDB_UNATTENDED 85 int debugger_on_panic = 0; 86 #else 87 int debugger_on_panic = 1; 88 #endif 89 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 90 &debugger_on_panic, 0, "Run debugger on kernel panic"); 91 92 #ifdef KDB_TRACE 93 int trace_on_panic = 1; 94 #else 95 int trace_on_panic = 0; 96 #endif 97 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 98 &trace_on_panic, 0, "Print stack trace on kernel panic"); 99 #endif /* KDB */ 100 101 int sync_on_panic = 1; 102 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 103 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 104 105 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 106 107 #ifdef HW_WDOG 108 /* 109 * If there is a hardware watchdog, point this at the function needed to 110 * hold it off. 111 * It's needed when the kernel needs to do some lengthy operations. 112 * e.g. in wd.c when dumping core.. It's most annoying to have 113 * your precious core-dump only half written because the wdog kicked in. 114 */ 115 watchdog_tickle_fn wdog_tickler = NULL; 116 #endif /* HW_WDOG */ 117 118 /* 119 * Variable panicstr contains argument to first call to panic; used as flag 120 * to indicate that the kernel has already called panic. 121 */ 122 const char *panicstr; 123 124 int dumping; /* system is dumping */ 125 static struct dumperinfo dumper; /* our selected dumper */ 126 127 /* Context information for dump-debuggers. */ 128 static struct pcb dumppcb; /* Registers. */ 129 static lwpid_t dumptid; /* Thread ID. */ 130 131 static void boot(int) __dead2; 132 static void poweroff_wait(void *, int); 133 static void shutdown_halt(void *junk, int howto); 134 static void shutdown_panic(void *junk, int howto); 135 static void shutdown_reset(void *junk, int howto); 136 137 /* register various local shutdown events */ 138 static void 139 shutdown_conf(void *unused) 140 { 141 142 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 143 SHUTDOWN_PRI_FIRST); 144 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 145 SHUTDOWN_PRI_LAST + 100); 146 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 147 SHUTDOWN_PRI_LAST + 100); 148 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 149 SHUTDOWN_PRI_LAST + 200); 150 } 151 152 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 153 154 /* 155 * The system call that results in a reboot 156 * 157 * MPSAFE 158 */ 159 /* ARGSUSED */ 160 int 161 reboot(struct thread *td, struct reboot_args *uap) 162 { 163 int error; 164 165 error = 0; 166 #ifdef MAC 167 error = mac_check_system_reboot(td->td_ucred, uap->opt); 168 #endif 169 if (error == 0) 170 error = suser(td); 171 if (error == 0) { 172 mtx_lock(&Giant); 173 boot(uap->opt); 174 mtx_unlock(&Giant); 175 } 176 return (error); 177 } 178 179 /* 180 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 181 */ 182 static int shutdown_howto = 0; 183 184 void 185 shutdown_nice(int howto) 186 { 187 188 shutdown_howto = howto; 189 190 /* Send a signal to init(8) and have it shutdown the world */ 191 if (initproc != NULL) { 192 PROC_LOCK(initproc); 193 psignal(initproc, SIGINT); 194 PROC_UNLOCK(initproc); 195 } else { 196 /* No init(8) running, so simply reboot */ 197 boot(RB_NOSYNC); 198 } 199 return; 200 } 201 static int waittime = -1; 202 203 static void 204 print_uptime(void) 205 { 206 int f; 207 struct timespec ts; 208 209 getnanouptime(&ts); 210 printf("Uptime: "); 211 f = 0; 212 if (ts.tv_sec >= 86400) { 213 printf("%ldd", (long)ts.tv_sec / 86400); 214 ts.tv_sec %= 86400; 215 f = 1; 216 } 217 if (f || ts.tv_sec >= 3600) { 218 printf("%ldh", (long)ts.tv_sec / 3600); 219 ts.tv_sec %= 3600; 220 f = 1; 221 } 222 if (f || ts.tv_sec >= 60) { 223 printf("%ldm", (long)ts.tv_sec / 60); 224 ts.tv_sec %= 60; 225 f = 1; 226 } 227 printf("%lds\n", (long)ts.tv_sec); 228 } 229 230 static void 231 doadump(void) 232 { 233 234 savectx(&dumppcb); 235 dumptid = curthread->td_tid; 236 dumping++; 237 dumpsys(&dumper); 238 } 239 240 /* 241 * Go through the rigmarole of shutting down.. 242 * this used to be in machdep.c but I'll be dammned if I could see 243 * anything machine dependant in it. 244 */ 245 static void 246 boot(int howto) 247 { 248 static int first_buf_printf = 1; 249 250 /* collect extra flags that shutdown_nice might have set */ 251 howto |= shutdown_howto; 252 253 /* We are out of the debugger now. */ 254 kdb_active = 0; 255 256 #ifdef SMP 257 if (smp_active) 258 printf("boot() called on cpu#%d\n", PCPU_GET(cpuid)); 259 #endif 260 /* 261 * Do any callouts that should be done BEFORE syncing the filesystems. 262 */ 263 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 264 265 /* 266 * Now sync filesystems 267 */ 268 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 269 register struct buf *bp; 270 int iter, nbusy, pbusy; 271 #ifndef PREEMPTION 272 int subiter; 273 #endif 274 275 waittime = 0; 276 277 sync(&thread0, NULL); 278 279 /* 280 * With soft updates, some buffers that are 281 * written will be remarked as dirty until other 282 * buffers are written. 283 */ 284 for (iter = pbusy = 0; iter < 20; iter++) { 285 nbusy = 0; 286 for (bp = &buf[nbuf]; --bp >= buf; ) { 287 if ((bp->b_flags & B_INVAL) == 0 && 288 BUF_REFCNT(bp) > 0) { 289 nbusy++; 290 } else if ((bp->b_flags & (B_DELWRI | B_INVAL)) 291 == B_DELWRI) { 292 /* bawrite(bp);*/ 293 nbusy++; 294 } 295 } 296 if (nbusy == 0) 297 break; 298 if (first_buf_printf) { 299 printf("syncing disks, buffers remaining... "); 300 first_buf_printf = 0; 301 } 302 printf("%d ", nbusy); 303 if (nbusy < pbusy) 304 iter = 0; 305 pbusy = nbusy; 306 sync(&thread0, NULL); 307 308 #ifdef PREEMPTION 309 /* 310 * Drop Giant and spin for a while to allow 311 * interrupt threads to run. 312 */ 313 DROP_GIANT(); 314 DELAY(50000 * iter); 315 PICKUP_GIANT(); 316 #else 317 /* 318 * Drop Giant and context switch several times to 319 * allow interrupt threads to run. 320 */ 321 DROP_GIANT(); 322 for (subiter = 0; subiter < 50 * iter; subiter++) { 323 mtx_lock_spin(&sched_lock); 324 mi_switch(SW_VOL, NULL); 325 mtx_unlock_spin(&sched_lock); 326 DELAY(1000); 327 } 328 PICKUP_GIANT(); 329 #endif 330 } 331 332 /* 333 * Count only busy local buffers to prevent forcing 334 * a fsck if we're just a client of a wedged NFS server 335 */ 336 nbusy = 0; 337 for (bp = &buf[nbuf]; --bp >= buf; ) { 338 if (((bp->b_flags&B_INVAL) == 0 && BUF_REFCNT(bp)) || 339 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 340 if (bp->b_dev == NULL) { 341 TAILQ_REMOVE(&mountlist, 342 bp->b_vp->v_mount, mnt_list); 343 continue; 344 } 345 nbusy++; 346 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 347 printf( 348 "%d: dev:%s, flags:%0x, blkno:%ld, lblkno:%ld\n", 349 nbusy, devtoname(bp->b_dev), 350 bp->b_flags, (long)bp->b_blkno, 351 (long)bp->b_lblkno); 352 #endif 353 } 354 } 355 if (nbusy) { 356 /* 357 * Failed to sync all blocks. Indicate this and don't 358 * unmount filesystems (thus forcing an fsck on reboot). 359 */ 360 printf("giving up on %d buffers\n", nbusy); 361 DELAY(5000000); /* 5 seconds */ 362 } else { 363 printf("done\n"); 364 /* 365 * Unmount filesystems 366 */ 367 if (panicstr == 0) 368 vfs_unmountall(); 369 } 370 DELAY(100000); /* wait for console output to finish */ 371 } 372 373 print_uptime(); 374 375 /* 376 * Ok, now do things that assume all filesystem activity has 377 * been completed. 378 */ 379 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 380 splhigh(); 381 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && 382 !cold && dumper.dumper != NULL && !dumping) 383 doadump(); 384 385 /* Now that we're going to really halt the system... */ 386 EVENTHANDLER_INVOKE(shutdown_final, howto); 387 388 for(;;) ; /* safety against shutdown_reset not working */ 389 /* NOTREACHED */ 390 } 391 392 /* 393 * If the shutdown was a clean halt, behave accordingly. 394 */ 395 static void 396 shutdown_halt(void *junk, int howto) 397 { 398 399 if (howto & RB_HALT) { 400 printf("\n"); 401 printf("The operating system has halted.\n"); 402 printf("Please press any key to reboot.\n\n"); 403 switch (cngetc()) { 404 case -1: /* No console, just die */ 405 cpu_halt(); 406 /* NOTREACHED */ 407 default: 408 howto &= ~RB_HALT; 409 break; 410 } 411 } 412 } 413 414 /* 415 * Check to see if the system paniced, pause and then reboot 416 * according to the specified delay. 417 */ 418 static void 419 shutdown_panic(void *junk, int howto) 420 { 421 int loop; 422 423 if (howto & RB_DUMP) { 424 if (PANIC_REBOOT_WAIT_TIME != 0) { 425 if (PANIC_REBOOT_WAIT_TIME != -1) { 426 printf("Automatic reboot in %d seconds - " 427 "press a key on the console to abort\n", 428 PANIC_REBOOT_WAIT_TIME); 429 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 430 loop > 0; --loop) { 431 DELAY(1000 * 100); /* 1/10th second */ 432 /* Did user type a key? */ 433 if (cncheckc() != -1) 434 break; 435 } 436 if (!loop) 437 return; 438 } 439 } else { /* zero time specified - reboot NOW */ 440 return; 441 } 442 printf("--> Press a key on the console to reboot,\n"); 443 printf("--> or switch off the system now.\n"); 444 cngetc(); 445 } 446 } 447 448 /* 449 * Everything done, now reset 450 */ 451 static void 452 shutdown_reset(void *junk, int howto) 453 { 454 455 printf("Rebooting...\n"); 456 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 457 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 458 cpu_reset(); 459 /* NOTREACHED */ /* assuming reset worked */ 460 } 461 462 #ifdef SMP 463 static u_int panic_cpu = NOCPU; 464 #endif 465 466 /* 467 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 468 * and then reboots. If we are called twice, then we avoid trying to sync 469 * the disks as this often leads to recursive panics. 470 * 471 * MPSAFE 472 */ 473 void 474 panic(const char *fmt, ...) 475 { 476 struct thread *td = curthread; 477 int bootopt, newpanic; 478 va_list ap; 479 static char buf[256]; 480 481 #ifdef SMP 482 /* 483 * We don't want multiple CPU's to panic at the same time, so we 484 * use panic_cpu as a simple spinlock. We have to keep checking 485 * panic_cpu if we are spinning in case the panic on the first 486 * CPU is canceled. 487 */ 488 if (panic_cpu != PCPU_GET(cpuid)) 489 while (atomic_cmpset_int(&panic_cpu, NOCPU, 490 PCPU_GET(cpuid)) == 0) 491 while (panic_cpu != NOCPU) 492 ; /* nothing */ 493 #endif 494 495 bootopt = RB_AUTOBOOT | RB_DUMP; 496 newpanic = 0; 497 if (panicstr) 498 bootopt |= RB_NOSYNC; 499 else { 500 panicstr = fmt; 501 newpanic = 1; 502 } 503 504 va_start(ap, fmt); 505 if (newpanic) { 506 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 507 panicstr = buf; 508 printf("panic: %s\n", buf); 509 } else { 510 printf("panic: "); 511 vprintf(fmt, ap); 512 printf("\n"); 513 } 514 va_end(ap); 515 #ifdef SMP 516 /* two separate prints in case of an unmapped page and trap */ 517 printf("cpuid = %d; ", PCPU_GET(cpuid)); 518 #ifdef APIC_IO 519 printf("lapic.id = %08x\n", lapic.id); 520 #else 521 printf("\n"); 522 #endif 523 #endif 524 525 #ifdef KDB 526 if (newpanic && trace_on_panic) 527 kdb_backtrace(); 528 if (debugger_on_panic) 529 kdb_enter("panic"); 530 #ifdef RESTARTABLE_PANICS 531 /* See if the user aborted the panic, in which case we continue. */ 532 if (panicstr == NULL) { 533 #ifdef SMP 534 atomic_store_rel_int(&panic_cpu, NOCPU); 535 #endif 536 return; 537 } 538 #endif 539 #endif 540 mtx_lock_spin(&sched_lock); 541 td->td_flags |= TDF_INPANIC; 542 mtx_unlock_spin(&sched_lock); 543 if (!sync_on_panic) 544 bootopt |= RB_NOSYNC; 545 boot(bootopt); 546 } 547 548 /* 549 * Support for poweroff delay. 550 */ 551 #ifndef POWEROFF_DELAY 552 # define POWEROFF_DELAY 5000 553 #endif 554 static int poweroff_delay = POWEROFF_DELAY; 555 556 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 557 &poweroff_delay, 0, ""); 558 559 static void 560 poweroff_wait(void *junk, int howto) 561 { 562 563 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 564 return; 565 DELAY(poweroff_delay * 1000); 566 } 567 568 /* 569 * Some system processes (e.g. syncer) need to be stopped at appropriate 570 * points in their main loops prior to a system shutdown, so that they 571 * won't interfere with the shutdown process (e.g. by holding a disk buf 572 * to cause sync to fail). For each of these system processes, register 573 * shutdown_kproc() as a handler for one of shutdown events. 574 */ 575 static int kproc_shutdown_wait = 60; 576 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 577 &kproc_shutdown_wait, 0, ""); 578 579 void 580 kproc_shutdown(void *arg, int howto) 581 { 582 struct proc *p; 583 char procname[MAXCOMLEN + 1]; 584 int error; 585 586 if (panicstr) 587 return; 588 589 p = (struct proc *)arg; 590 strlcpy(procname, p->p_comm, sizeof(procname)); 591 printf("Waiting (max %d seconds) for system process `%s' to stop...\n", 592 kproc_shutdown_wait, procname); 593 error = kthread_suspend(p, kproc_shutdown_wait * hz); 594 595 if (error == EWOULDBLOCK) 596 printf("Stop of '%s' timed out.\n", procname); 597 else 598 printf("Process '%s' stopped.\n", procname); 599 } 600 601 /* Registration of dumpers */ 602 int 603 set_dumper(struct dumperinfo *di) 604 { 605 606 if (di == NULL) { 607 bzero(&dumper, sizeof dumper); 608 return (0); 609 } 610 if (dumper.dumper != NULL) 611 return (EBUSY); 612 dumper = *di; 613 return (0); 614 } 615 616 #if defined(__powerpc__) 617 void 618 dumpsys(struct dumperinfo *di __unused) 619 { 620 621 printf("Kernel dumps not implemented on this architecture\n"); 622 } 623 #endif 624