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_ddb.h" 41 #include "opt_kdb.h" 42 #include "opt_panic.h" 43 #include "opt_sched.h" 44 #include "opt_watchdog.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/jail.h> 54 #include <sys/kdb.h> 55 #include <sys/kernel.h> 56 #include <sys/kerneldump.h> 57 #include <sys/kthread.h> 58 #include <sys/ktr.h> 59 #include <sys/malloc.h> 60 #include <sys/mount.h> 61 #include <sys/priv.h> 62 #include <sys/proc.h> 63 #include <sys/reboot.h> 64 #include <sys/resourcevar.h> 65 #include <sys/rwlock.h> 66 #include <sys/sched.h> 67 #include <sys/smp.h> 68 #include <sys/sysctl.h> 69 #include <sys/sysproto.h> 70 #include <sys/vnode.h> 71 #include <sys/watchdog.h> 72 73 #include <ddb/ddb.h> 74 75 #include <machine/cpu.h> 76 #include <machine/pcb.h> 77 #include <machine/smp.h> 78 79 #include <security/mac/mac_framework.h> 80 81 #include <vm/vm.h> 82 #include <vm/vm_object.h> 83 #include <vm/vm_page.h> 84 #include <vm/vm_pager.h> 85 #include <vm/swap_pager.h> 86 87 #include <sys/signalvar.h> 88 89 #ifndef PANIC_REBOOT_WAIT_TIME 90 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 91 #endif 92 93 /* 94 * Note that stdarg.h and the ANSI style va_start macro is used for both 95 * ANSI and traditional C compilers. 96 */ 97 #include <machine/stdarg.h> 98 99 #ifdef KDB 100 #ifdef KDB_UNATTENDED 101 int debugger_on_panic = 0; 102 #else 103 int debugger_on_panic = 1; 104 #endif 105 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, 106 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN, 107 &debugger_on_panic, 0, "Run debugger on kernel panic"); 108 TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic); 109 110 #ifdef KDB_TRACE 111 static int trace_on_panic = 1; 112 #else 113 static int trace_on_panic = 0; 114 #endif 115 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, 116 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN, 117 &trace_on_panic, 0, "Print stack trace on kernel panic"); 118 TUNABLE_INT("debug.trace_on_panic", &trace_on_panic); 119 #endif /* KDB */ 120 121 static int sync_on_panic = 0; 122 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN, 123 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 124 TUNABLE_INT("kern.sync_on_panic", &sync_on_panic); 125 126 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, 127 "Shutdown environment"); 128 129 #ifndef DIAGNOSTIC 130 static int show_busybufs; 131 #else 132 static int show_busybufs = 1; 133 #endif 134 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW, 135 &show_busybufs, 0, ""); 136 137 /* 138 * Variable panicstr contains argument to first call to panic; used as flag 139 * to indicate that the kernel has already called panic. 140 */ 141 const char *panicstr; 142 143 int dumping; /* system is dumping */ 144 int rebooting; /* system is rebooting */ 145 static struct dumperinfo dumper; /* our selected dumper */ 146 147 /* Context information for dump-debuggers. */ 148 static struct pcb dumppcb; /* Registers. */ 149 lwpid_t dumptid; /* Thread ID. */ 150 151 static void poweroff_wait(void *, int); 152 static void shutdown_halt(void *junk, int howto); 153 static void shutdown_panic(void *junk, int howto); 154 static void shutdown_reset(void *junk, int howto); 155 static void vpanic(const char *fmt, va_list ap) __dead2; 156 157 /* register various local shutdown events */ 158 static void 159 shutdown_conf(void *unused) 160 { 161 162 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 163 SHUTDOWN_PRI_FIRST); 164 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 165 SHUTDOWN_PRI_LAST + 100); 166 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 167 SHUTDOWN_PRI_LAST + 100); 168 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 169 SHUTDOWN_PRI_LAST + 200); 170 } 171 172 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL); 173 174 /* 175 * The system call that results in a reboot. 176 */ 177 /* ARGSUSED */ 178 int 179 sys_reboot(struct thread *td, struct reboot_args *uap) 180 { 181 int error; 182 183 error = 0; 184 #ifdef MAC 185 error = mac_system_check_reboot(td->td_ucred, uap->opt); 186 #endif 187 if (error == 0) 188 error = priv_check(td, PRIV_REBOOT); 189 if (error == 0) { 190 mtx_lock(&Giant); 191 kern_reboot(uap->opt); 192 mtx_unlock(&Giant); 193 } 194 return (error); 195 } 196 197 /* 198 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 199 */ 200 static int shutdown_howto = 0; 201 202 void 203 shutdown_nice(int howto) 204 { 205 206 shutdown_howto = howto; 207 208 /* Send a signal to init(8) and have it shutdown the world */ 209 if (initproc != NULL) { 210 PROC_LOCK(initproc); 211 kern_psignal(initproc, SIGINT); 212 PROC_UNLOCK(initproc); 213 } else { 214 /* No init(8) running, so simply reboot */ 215 kern_reboot(RB_NOSYNC); 216 } 217 return; 218 } 219 static int waittime = -1; 220 221 static void 222 print_uptime(void) 223 { 224 int f; 225 struct timespec ts; 226 227 getnanouptime(&ts); 228 printf("Uptime: "); 229 f = 0; 230 if (ts.tv_sec >= 86400) { 231 printf("%ldd", (long)ts.tv_sec / 86400); 232 ts.tv_sec %= 86400; 233 f = 1; 234 } 235 if (f || ts.tv_sec >= 3600) { 236 printf("%ldh", (long)ts.tv_sec / 3600); 237 ts.tv_sec %= 3600; 238 f = 1; 239 } 240 if (f || ts.tv_sec >= 60) { 241 printf("%ldm", (long)ts.tv_sec / 60); 242 ts.tv_sec %= 60; 243 f = 1; 244 } 245 printf("%lds\n", (long)ts.tv_sec); 246 } 247 248 int 249 doadump(boolean_t textdump) 250 { 251 boolean_t coredump; 252 253 if (dumping) 254 return (EBUSY); 255 if (dumper.dumper == NULL) 256 return (ENXIO); 257 258 savectx(&dumppcb); 259 dumptid = curthread->td_tid; 260 dumping++; 261 262 coredump = TRUE; 263 #ifdef DDB 264 if (textdump && textdump_pending) { 265 coredump = FALSE; 266 textdump_dumpsys(&dumper); 267 } 268 #endif 269 if (coredump) 270 dumpsys(&dumper); 271 272 dumping--; 273 return (0); 274 } 275 276 static int 277 isbufbusy(struct buf *bp) 278 { 279 if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 && 280 BUF_ISLOCKED(bp)) || 281 ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI)) 282 return (1); 283 return (0); 284 } 285 286 /* 287 * Shutdown the system cleanly to prepare for reboot, halt, or power off. 288 */ 289 void 290 kern_reboot(int howto) 291 { 292 static int first_buf_printf = 1; 293 294 #if defined(SMP) 295 /* 296 * Bind us to CPU 0 so that all shutdown code runs there. Some 297 * systems don't shutdown properly (i.e., ACPI power off) if we 298 * run on another processor. 299 */ 300 if (!SCHEDULER_STOPPED()) { 301 thread_lock(curthread); 302 sched_bind(curthread, 0); 303 thread_unlock(curthread); 304 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0")); 305 } 306 #endif 307 /* We're in the process of rebooting. */ 308 rebooting = 1; 309 310 /* collect extra flags that shutdown_nice might have set */ 311 howto |= shutdown_howto; 312 313 /* We are out of the debugger now. */ 314 kdb_active = 0; 315 316 /* 317 * Do any callouts that should be done BEFORE syncing the filesystems. 318 */ 319 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 320 321 /* 322 * Now sync filesystems 323 */ 324 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 325 register struct buf *bp; 326 int iter, nbusy, pbusy; 327 #ifndef PREEMPTION 328 int subiter; 329 #endif 330 331 waittime = 0; 332 333 wdog_kern_pat(WD_LASTVAL); 334 sys_sync(curthread, NULL); 335 336 /* 337 * With soft updates, some buffers that are 338 * written will be remarked as dirty until other 339 * buffers are written. 340 */ 341 for (iter = pbusy = 0; iter < 20; iter++) { 342 nbusy = 0; 343 for (bp = &buf[nbuf]; --bp >= buf; ) 344 if (isbufbusy(bp)) 345 nbusy++; 346 if (nbusy == 0) { 347 if (first_buf_printf) 348 printf("All buffers synced."); 349 break; 350 } 351 if (first_buf_printf) { 352 printf("Syncing disks, buffers remaining... "); 353 first_buf_printf = 0; 354 } 355 printf("%d ", nbusy); 356 if (nbusy < pbusy) 357 iter = 0; 358 pbusy = nbusy; 359 360 wdog_kern_pat(WD_LASTVAL); 361 sys_sync(curthread, NULL); 362 363 #ifdef PREEMPTION 364 /* 365 * Drop Giant and spin for a while to allow 366 * interrupt threads to run. 367 */ 368 DROP_GIANT(); 369 DELAY(50000 * iter); 370 PICKUP_GIANT(); 371 #else 372 /* 373 * Drop Giant and context switch several times to 374 * allow interrupt threads to run. 375 */ 376 DROP_GIANT(); 377 for (subiter = 0; subiter < 50 * iter; subiter++) { 378 thread_lock(curthread); 379 mi_switch(SW_VOL, NULL); 380 thread_unlock(curthread); 381 DELAY(1000); 382 } 383 PICKUP_GIANT(); 384 #endif 385 } 386 printf("\n"); 387 /* 388 * Count only busy local buffers to prevent forcing 389 * a fsck if we're just a client of a wedged NFS server 390 */ 391 nbusy = 0; 392 for (bp = &buf[nbuf]; --bp >= buf; ) { 393 if (isbufbusy(bp)) { 394 #if 0 395 /* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */ 396 if (bp->b_dev == NULL) { 397 TAILQ_REMOVE(&mountlist, 398 bp->b_vp->v_mount, mnt_list); 399 continue; 400 } 401 #endif 402 nbusy++; 403 if (show_busybufs > 0) { 404 printf( 405 "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:", 406 nbusy, bp, bp->b_vp, bp->b_flags, 407 (intmax_t)bp->b_blkno, 408 (intmax_t)bp->b_lblkno); 409 BUF_LOCKPRINTINFO(bp); 410 if (show_busybufs > 1) 411 vn_printf(bp->b_vp, 412 "vnode content: "); 413 } 414 } 415 } 416 if (nbusy) { 417 /* 418 * Failed to sync all blocks. Indicate this and don't 419 * unmount filesystems (thus forcing an fsck on reboot). 420 */ 421 printf("Giving up on %d buffers\n", nbusy); 422 DELAY(5000000); /* 5 seconds */ 423 } else { 424 if (!first_buf_printf) 425 printf("Final sync complete\n"); 426 /* 427 * Unmount filesystems 428 */ 429 if (panicstr == 0) 430 vfs_unmountall(); 431 } 432 swapoff_all(); 433 DELAY(100000); /* wait for console output to finish */ 434 } 435 436 print_uptime(); 437 438 cngrab(); 439 440 /* 441 * Ok, now do things that assume all filesystem activity has 442 * been completed. 443 */ 444 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 445 446 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping) 447 doadump(TRUE); 448 449 /* Now that we're going to really halt the system... */ 450 EVENTHANDLER_INVOKE(shutdown_final, howto); 451 452 for(;;) ; /* safety against shutdown_reset not working */ 453 /* NOTREACHED */ 454 } 455 456 /* 457 * If the shutdown was a clean halt, behave accordingly. 458 */ 459 static void 460 shutdown_halt(void *junk, int howto) 461 { 462 463 if (howto & RB_HALT) { 464 printf("\n"); 465 printf("The operating system has halted.\n"); 466 printf("Please press any key to reboot.\n\n"); 467 switch (cngetc()) { 468 case -1: /* No console, just die */ 469 cpu_halt(); 470 /* NOTREACHED */ 471 default: 472 howto &= ~RB_HALT; 473 break; 474 } 475 } 476 } 477 478 /* 479 * Check to see if the system paniced, pause and then reboot 480 * according to the specified delay. 481 */ 482 static void 483 shutdown_panic(void *junk, int howto) 484 { 485 int loop; 486 487 if (howto & RB_DUMP) { 488 if (PANIC_REBOOT_WAIT_TIME != 0) { 489 if (PANIC_REBOOT_WAIT_TIME != -1) { 490 printf("Automatic reboot in %d seconds - " 491 "press a key on the console to abort\n", 492 PANIC_REBOOT_WAIT_TIME); 493 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 494 loop > 0; --loop) { 495 DELAY(1000 * 100); /* 1/10th second */ 496 /* Did user type a key? */ 497 if (cncheckc() != -1) 498 break; 499 } 500 if (!loop) 501 return; 502 } 503 } else { /* zero time specified - reboot NOW */ 504 return; 505 } 506 printf("--> Press a key on the console to reboot,\n"); 507 printf("--> or switch off the system now.\n"); 508 cngetc(); 509 } 510 } 511 512 /* 513 * Everything done, now reset 514 */ 515 static void 516 shutdown_reset(void *junk, int howto) 517 { 518 519 printf("Rebooting...\n"); 520 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 521 522 /* 523 * Acquiring smp_ipi_mtx here has a double effect: 524 * - it disables interrupts avoiding CPU0 preemption 525 * by fast handlers (thus deadlocking against other CPUs) 526 * - it avoids deadlocks against smp_rendezvous() or, more 527 * generally, threads busy-waiting, with this spinlock held, 528 * and waiting for responses by threads on other CPUs 529 * (ie. smp_tlb_shootdown()). 530 * 531 * For the !SMP case it just needs to handle the former problem. 532 */ 533 #ifdef SMP 534 mtx_lock_spin(&smp_ipi_mtx); 535 #else 536 spinlock_enter(); 537 #endif 538 539 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 540 cpu_reset(); 541 /* NOTREACHED */ /* assuming reset worked */ 542 } 543 544 #if defined(WITNESS) || defined(INVARIANTS) 545 static int kassert_warn_only = 0; 546 #ifdef KDB 547 static int kassert_do_kdb = 0; 548 #endif 549 #ifdef KTR 550 static int kassert_do_ktr = 0; 551 #endif 552 static int kassert_do_log = 1; 553 static int kassert_log_pps_limit = 4; 554 static int kassert_log_mute_at = 0; 555 static int kassert_log_panic_at = 0; 556 static int kassert_warnings = 0; 557 558 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options"); 559 560 SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RW | CTLFLAG_TUN, 561 &kassert_warn_only, 0, 562 "KASSERT triggers a panic (1) or just a warning (0)"); 563 TUNABLE_INT("debug.kassert.warn_only", &kassert_warn_only); 564 565 #ifdef KDB 566 SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RW | CTLFLAG_TUN, 567 &kassert_do_kdb, 0, "KASSERT will enter the debugger"); 568 TUNABLE_INT("debug.kassert.do_kdb", &kassert_do_kdb); 569 #endif 570 571 #ifdef KTR 572 SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RW | CTLFLAG_TUN, 573 &kassert_do_ktr, 0, 574 "KASSERT does a KTR, set this to the KTRMASK you want"); 575 TUNABLE_INT("debug.kassert.do_ktr", &kassert_do_ktr); 576 #endif 577 578 SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RW | CTLFLAG_TUN, 579 &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)"); 580 TUNABLE_INT("debug.kassert.do_log", &kassert_do_log); 581 582 SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RW | CTLFLAG_TUN, 583 &kassert_warnings, 0, "number of KASSERTs that have been triggered"); 584 TUNABLE_INT("debug.kassert.warnings", &kassert_warnings); 585 586 SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RW | CTLFLAG_TUN, 587 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic"); 588 TUNABLE_INT("debug.kassert.log_panic_at", &kassert_log_panic_at); 589 590 SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RW | CTLFLAG_TUN, 591 &kassert_log_pps_limit, 0, "limit number of log messages per second"); 592 TUNABLE_INT("debug.kassert.log_pps_limit", &kassert_log_pps_limit); 593 594 SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RW | CTLFLAG_TUN, 595 &kassert_log_mute_at, 0, "max number of KASSERTS to log"); 596 TUNABLE_INT("debug.kassert.log_mute_at", &kassert_log_mute_at); 597 598 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS); 599 600 SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert, 601 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0, 602 kassert_sysctl_kassert, "I", "set to trigger a test kassert"); 603 604 static int 605 kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS) 606 { 607 int error, i; 608 609 error = sysctl_wire_old_buffer(req, sizeof(int)); 610 if (error == 0) { 611 i = 0; 612 error = sysctl_handle_int(oidp, &i, 0, req); 613 } 614 if (error != 0 || req->newptr == NULL) 615 return (error); 616 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i)); 617 return (0); 618 } 619 620 /* 621 * Called by KASSERT, this decides if we will panic 622 * or if we will log via printf and/or ktr. 623 */ 624 void 625 kassert_panic(const char *fmt, ...) 626 { 627 static char buf[256]; 628 va_list ap; 629 630 va_start(ap, fmt); 631 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 632 va_end(ap); 633 634 /* 635 * panic if we're not just warning, or if we've exceeded 636 * kassert_log_panic_at warnings. 637 */ 638 if (!kassert_warn_only || 639 (kassert_log_panic_at > 0 && 640 kassert_warnings >= kassert_log_panic_at)) { 641 va_start(ap, fmt); 642 vpanic(fmt, ap); 643 /* NORETURN */ 644 } 645 #ifdef KTR 646 if (kassert_do_ktr) 647 CTR0(ktr_mask, buf); 648 #endif /* KTR */ 649 /* 650 * log if we've not yet met the mute limit. 651 */ 652 if (kassert_do_log && 653 (kassert_log_mute_at == 0 || 654 kassert_warnings < kassert_log_mute_at)) { 655 static struct timeval lasterr; 656 static int curerr; 657 658 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) { 659 printf("KASSERT failed: %s\n", buf); 660 kdb_backtrace(); 661 } 662 } 663 #ifdef KDB 664 if (kassert_do_kdb) { 665 kdb_enter(KDB_WHY_KASSERT, buf); 666 } 667 #endif 668 atomic_add_int(&kassert_warnings, 1); 669 } 670 #endif 671 672 /* 673 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 674 * and then reboots. If we are called twice, then we avoid trying to sync 675 * the disks as this often leads to recursive panics. 676 */ 677 void 678 panic(const char *fmt, ...) 679 { 680 va_list ap; 681 682 va_start(ap, fmt); 683 vpanic(fmt, ap); 684 } 685 686 static void 687 vpanic(const char *fmt, va_list ap) 688 { 689 #ifdef SMP 690 cpuset_t other_cpus; 691 #endif 692 struct thread *td = curthread; 693 int bootopt, newpanic; 694 static char buf[256]; 695 696 spinlock_enter(); 697 698 #ifdef SMP 699 /* 700 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from 701 * concurrently entering panic. Only the winner will proceed 702 * further. 703 */ 704 if (panicstr == NULL && !kdb_active) { 705 other_cpus = all_cpus; 706 CPU_CLR(PCPU_GET(cpuid), &other_cpus); 707 stop_cpus_hard(other_cpus); 708 } 709 710 /* 711 * We set stop_scheduler here and not in the block above, 712 * because we want to ensure that if panic has been called and 713 * stop_scheduler_on_panic is true, then stop_scheduler will 714 * always be set. Even if panic has been entered from kdb. 715 */ 716 td->td_stopsched = 1; 717 #endif 718 719 bootopt = RB_AUTOBOOT; 720 newpanic = 0; 721 if (panicstr) 722 bootopt |= RB_NOSYNC; 723 else { 724 bootopt |= RB_DUMP; 725 panicstr = fmt; 726 newpanic = 1; 727 } 728 729 if (newpanic) { 730 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 731 panicstr = buf; 732 cngrab(); 733 printf("panic: %s\n", buf); 734 } else { 735 printf("panic: "); 736 vprintf(fmt, ap); 737 printf("\n"); 738 } 739 #ifdef SMP 740 printf("cpuid = %d\n", PCPU_GET(cpuid)); 741 #endif 742 743 #ifdef KDB 744 if (newpanic && trace_on_panic) 745 kdb_backtrace(); 746 if (debugger_on_panic) 747 kdb_enter(KDB_WHY_PANIC, "panic"); 748 #endif 749 /*thread_lock(td); */ 750 td->td_flags |= TDF_INPANIC; 751 /* thread_unlock(td); */ 752 if (!sync_on_panic) 753 bootopt |= RB_NOSYNC; 754 kern_reboot(bootopt); 755 } 756 757 /* 758 * Support for poweroff delay. 759 * 760 * Please note that setting this delay too short might power off your machine 761 * before the write cache on your hard disk has been flushed, leading to 762 * soft-updates inconsistencies. 763 */ 764 #ifndef POWEROFF_DELAY 765 # define POWEROFF_DELAY 5000 766 #endif 767 static int poweroff_delay = POWEROFF_DELAY; 768 769 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 770 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)"); 771 772 static void 773 poweroff_wait(void *junk, int howto) 774 { 775 776 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 777 return; 778 DELAY(poweroff_delay * 1000); 779 } 780 781 /* 782 * Some system processes (e.g. syncer) need to be stopped at appropriate 783 * points in their main loops prior to a system shutdown, so that they 784 * won't interfere with the shutdown process (e.g. by holding a disk buf 785 * to cause sync to fail). For each of these system processes, register 786 * shutdown_kproc() as a handler for one of shutdown events. 787 */ 788 static int kproc_shutdown_wait = 60; 789 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 790 &kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process"); 791 792 void 793 kproc_shutdown(void *arg, int howto) 794 { 795 struct proc *p; 796 int error; 797 798 if (panicstr) 799 return; 800 801 p = (struct proc *)arg; 802 printf("Waiting (max %d seconds) for system process `%s' to stop...", 803 kproc_shutdown_wait, p->p_comm); 804 error = kproc_suspend(p, kproc_shutdown_wait * hz); 805 806 if (error == EWOULDBLOCK) 807 printf("timed out\n"); 808 else 809 printf("done\n"); 810 } 811 812 void 813 kthread_shutdown(void *arg, int howto) 814 { 815 struct thread *td; 816 int error; 817 818 if (panicstr) 819 return; 820 821 td = (struct thread *)arg; 822 printf("Waiting (max %d seconds) for system thread `%s' to stop...", 823 kproc_shutdown_wait, td->td_name); 824 error = kthread_suspend(td, kproc_shutdown_wait * hz); 825 826 if (error == EWOULDBLOCK) 827 printf("timed out\n"); 828 else 829 printf("done\n"); 830 } 831 832 static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)]; 833 SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD, 834 dumpdevname, 0, "Device for kernel dumps"); 835 836 /* Registration of dumpers */ 837 int 838 set_dumper(struct dumperinfo *di, const char *devname) 839 { 840 size_t wantcopy; 841 842 if (di == NULL) { 843 bzero(&dumper, sizeof dumper); 844 dumpdevname[0] = '\0'; 845 return (0); 846 } 847 if (dumper.dumper != NULL) 848 return (EBUSY); 849 dumper = *di; 850 wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname)); 851 if (wantcopy >= sizeof(dumpdevname)) { 852 printf("set_dumper: device name truncated from '%s' -> '%s'\n", 853 devname, dumpdevname); 854 } 855 return (0); 856 } 857 858 /* Call dumper with bounds checking. */ 859 int 860 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical, 861 off_t offset, size_t length) 862 { 863 864 if (length != 0 && (offset < di->mediaoffset || 865 offset - di->mediaoffset + length > di->mediasize)) { 866 printf("Attempt to write outside dump device boundaries.\n" 867 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n", 868 (intmax_t)offset, (intmax_t)di->mediaoffset, 869 (uintmax_t)length, (intmax_t)di->mediasize); 870 return (ENOSPC); 871 } 872 return (di->dumper(di->priv, virtual, physical, offset, length)); 873 } 874 875 void 876 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver, 877 uint64_t dumplen, uint32_t blksz) 878 { 879 880 bzero(kdh, sizeof(*kdh)); 881 strncpy(kdh->magic, magic, sizeof(kdh->magic)); 882 strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture)); 883 kdh->version = htod32(KERNELDUMPVERSION); 884 kdh->architectureversion = htod32(archver); 885 kdh->dumplength = htod64(dumplen); 886 kdh->dumptime = htod64(time_second); 887 kdh->blocksize = htod32(blksz); 888 strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname)); 889 strncpy(kdh->versionstring, version, sizeof(kdh->versionstring)); 890 if (panicstr != NULL) 891 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring)); 892 kdh->parity = kerneldump_parity(kdh); 893 } 894