kern_shutdown.c revision 283676
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: stable/10/sys/kern/kern_shutdown.c 283676 2015-05-29 04:01:39Z markj $"); 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 92static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME; 93SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RW | CTLFLAG_TUN, 94 &panic_reboot_wait_time, 0, 95 "Seconds to wait before rebooting after a panic"); 96TUNABLE_INT("kern.panic_reboot_wait_time", &panic_reboot_wait_time); 97 98/* 99 * Note that stdarg.h and the ANSI style va_start macro is used for both 100 * ANSI and traditional C compilers. 101 */ 102#include <machine/stdarg.h> 103 104#ifdef KDB 105#ifdef KDB_UNATTENDED 106int debugger_on_panic = 0; 107#else 108int debugger_on_panic = 1; 109#endif 110SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, 111 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN, 112 &debugger_on_panic, 0, "Run debugger on kernel panic"); 113TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic); 114 115#ifdef KDB_TRACE 116static int trace_on_panic = 1; 117#else 118static int trace_on_panic = 0; 119#endif 120SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, 121 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN, 122 &trace_on_panic, 0, "Print stack trace on kernel panic"); 123TUNABLE_INT("debug.trace_on_panic", &trace_on_panic); 124#endif /* KDB */ 125 126static int sync_on_panic = 0; 127SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN, 128 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 129TUNABLE_INT("kern.sync_on_panic", &sync_on_panic); 130 131static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, 132 "Shutdown environment"); 133 134#ifndef DIAGNOSTIC 135static int show_busybufs; 136#else 137static int show_busybufs = 1; 138#endif 139SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW, 140 &show_busybufs, 0, ""); 141 142/* 143 * Variable panicstr contains argument to first call to panic; used as flag 144 * to indicate that the kernel has already called panic. 145 */ 146const char *panicstr; 147 148int dumping; /* system is dumping */ 149int rebooting; /* system is rebooting */ 150static struct dumperinfo dumper; /* our selected dumper */ 151 152/* Context information for dump-debuggers. */ 153static struct pcb dumppcb; /* Registers. */ 154lwpid_t dumptid; /* Thread ID. */ 155 156static void poweroff_wait(void *, int); 157static void shutdown_halt(void *junk, int howto); 158static void shutdown_panic(void *junk, int howto); 159static void shutdown_reset(void *junk, int howto); 160 161/* register various local shutdown events */ 162static void 163shutdown_conf(void *unused) 164{ 165 166 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 167 SHUTDOWN_PRI_FIRST); 168 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 169 SHUTDOWN_PRI_LAST + 100); 170 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 171 SHUTDOWN_PRI_LAST + 100); 172 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 173 SHUTDOWN_PRI_LAST + 200); 174} 175 176SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL); 177 178/* 179 * The system call that results in a reboot. 180 */ 181/* ARGSUSED */ 182int 183sys_reboot(struct thread *td, struct reboot_args *uap) 184{ 185 int error; 186 187 error = 0; 188#ifdef MAC 189 error = mac_system_check_reboot(td->td_ucred, uap->opt); 190#endif 191 if (error == 0) 192 error = priv_check(td, PRIV_REBOOT); 193 if (error == 0) { 194 mtx_lock(&Giant); 195 kern_reboot(uap->opt); 196 mtx_unlock(&Giant); 197 } 198 return (error); 199} 200 201/* 202 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 203 */ 204static int shutdown_howto = 0; 205 206void 207shutdown_nice(int howto) 208{ 209 210 shutdown_howto = howto; 211 212 /* Send a signal to init(8) and have it shutdown the world */ 213 if (initproc != NULL) { 214 PROC_LOCK(initproc); 215 kern_psignal(initproc, SIGINT); 216 PROC_UNLOCK(initproc); 217 } else { 218 /* No init(8) running, so simply reboot */ 219 kern_reboot(RB_NOSYNC); 220 } 221 return; 222} 223static int waittime = -1; 224 225static void 226print_uptime(void) 227{ 228 int f; 229 struct timespec ts; 230 231 getnanouptime(&ts); 232 printf("Uptime: "); 233 f = 0; 234 if (ts.tv_sec >= 86400) { 235 printf("%ldd", (long)ts.tv_sec / 86400); 236 ts.tv_sec %= 86400; 237 f = 1; 238 } 239 if (f || ts.tv_sec >= 3600) { 240 printf("%ldh", (long)ts.tv_sec / 3600); 241 ts.tv_sec %= 3600; 242 f = 1; 243 } 244 if (f || ts.tv_sec >= 60) { 245 printf("%ldm", (long)ts.tv_sec / 60); 246 ts.tv_sec %= 60; 247 f = 1; 248 } 249 printf("%lds\n", (long)ts.tv_sec); 250} 251 252int 253doadump(boolean_t textdump) 254{ 255 boolean_t coredump; 256 257 if (dumping) 258 return (EBUSY); 259 if (dumper.dumper == NULL) 260 return (ENXIO); 261 262 savectx(&dumppcb); 263 dumptid = curthread->td_tid; 264 dumping++; 265 266 coredump = TRUE; 267#ifdef DDB 268 if (textdump && textdump_pending) { 269 coredump = FALSE; 270 textdump_dumpsys(&dumper); 271 } 272#endif 273 if (coredump) 274 dumpsys(&dumper); 275 276 dumping--; 277 return (0); 278} 279 280static int 281isbufbusy(struct buf *bp) 282{ 283 if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 && 284 BUF_ISLOCKED(bp)) || 285 ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI)) 286 return (1); 287 return (0); 288} 289 290/* 291 * Shutdown the system cleanly to prepare for reboot, halt, or power off. 292 */ 293void 294kern_reboot(int howto) 295{ 296 static int first_buf_printf = 1; 297 298#if defined(SMP) 299 /* 300 * Bind us to CPU 0 so that all shutdown code runs there. Some 301 * systems don't shutdown properly (i.e., ACPI power off) if we 302 * run on another processor. 303 */ 304 if (!SCHEDULER_STOPPED()) { 305 thread_lock(curthread); 306 sched_bind(curthread, 0); 307 thread_unlock(curthread); 308 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0")); 309 } 310#endif 311 /* We're in the process of rebooting. */ 312 rebooting = 1; 313 314 /* collect extra flags that shutdown_nice might have set */ 315 howto |= shutdown_howto; 316 317 /* We are out of the debugger now. */ 318 kdb_active = 0; 319 320 /* 321 * Do any callouts that should be done BEFORE syncing the filesystems. 322 */ 323 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 324 325 /* 326 * Now sync filesystems 327 */ 328 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 329 register struct buf *bp; 330 int iter, nbusy, pbusy; 331#ifndef PREEMPTION 332 int subiter; 333#endif 334 335 waittime = 0; 336 337 wdog_kern_pat(WD_LASTVAL); 338 sys_sync(curthread, NULL); 339 340 /* 341 * With soft updates, some buffers that are 342 * written will be remarked as dirty until other 343 * buffers are written. 344 */ 345 for (iter = pbusy = 0; iter < 20; iter++) { 346 nbusy = 0; 347 for (bp = &buf[nbuf]; --bp >= buf; ) 348 if (isbufbusy(bp)) 349 nbusy++; 350 if (nbusy == 0) { 351 if (first_buf_printf) 352 printf("All buffers synced."); 353 break; 354 } 355 if (first_buf_printf) { 356 printf("Syncing disks, buffers remaining... "); 357 first_buf_printf = 0; 358 } 359 printf("%d ", nbusy); 360 if (nbusy < pbusy) 361 iter = 0; 362 pbusy = nbusy; 363 364 wdog_kern_pat(WD_LASTVAL); 365 sys_sync(curthread, NULL); 366 367#ifdef PREEMPTION 368 /* 369 * Drop Giant and spin for a while to allow 370 * interrupt threads to run. 371 */ 372 DROP_GIANT(); 373 DELAY(50000 * iter); 374 PICKUP_GIANT(); 375#else 376 /* 377 * Drop Giant and context switch several times to 378 * allow interrupt threads to run. 379 */ 380 DROP_GIANT(); 381 for (subiter = 0; subiter < 50 * iter; subiter++) { 382 thread_lock(curthread); 383 mi_switch(SW_VOL, NULL); 384 thread_unlock(curthread); 385 DELAY(1000); 386 } 387 PICKUP_GIANT(); 388#endif 389 } 390 printf("\n"); 391 /* 392 * Count only busy local buffers to prevent forcing 393 * a fsck if we're just a client of a wedged NFS server 394 */ 395 nbusy = 0; 396 for (bp = &buf[nbuf]; --bp >= buf; ) { 397 if (isbufbusy(bp)) { 398#if 0 399/* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */ 400 if (bp->b_dev == NULL) { 401 TAILQ_REMOVE(&mountlist, 402 bp->b_vp->v_mount, mnt_list); 403 continue; 404 } 405#endif 406 nbusy++; 407 if (show_busybufs > 0) { 408 printf( 409 "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:", 410 nbusy, bp, bp->b_vp, bp->b_flags, 411 (intmax_t)bp->b_blkno, 412 (intmax_t)bp->b_lblkno); 413 BUF_LOCKPRINTINFO(bp); 414 if (show_busybufs > 1) 415 vn_printf(bp->b_vp, 416 "vnode content: "); 417 } 418 } 419 } 420 if (nbusy) { 421 /* 422 * Failed to sync all blocks. Indicate this and don't 423 * unmount filesystems (thus forcing an fsck on reboot). 424 */ 425 printf("Giving up on %d buffers\n", nbusy); 426 DELAY(5000000); /* 5 seconds */ 427 } else { 428 if (!first_buf_printf) 429 printf("Final sync complete\n"); 430 /* 431 * Unmount filesystems 432 */ 433 if (panicstr == 0) 434 vfs_unmountall(); 435 } 436 swapoff_all(); 437 DELAY(100000); /* wait for console output to finish */ 438 } 439 440 print_uptime(); 441 442 cngrab(); 443 444 /* 445 * Ok, now do things that assume all filesystem activity has 446 * been completed. 447 */ 448 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 449 450 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping) 451 doadump(TRUE); 452 453 /* Now that we're going to really halt the system... */ 454 EVENTHANDLER_INVOKE(shutdown_final, howto); 455 456 for(;;) ; /* safety against shutdown_reset not working */ 457 /* NOTREACHED */ 458} 459 460/* 461 * If the shutdown was a clean halt, behave accordingly. 462 */ 463static void 464shutdown_halt(void *junk, int howto) 465{ 466 467 if (howto & RB_HALT) { 468 printf("\n"); 469 printf("The operating system has halted.\n"); 470 printf("Please press any key to reboot.\n\n"); 471 switch (cngetc()) { 472 case -1: /* No console, just die */ 473 cpu_halt(); 474 /* NOTREACHED */ 475 default: 476 howto &= ~RB_HALT; 477 break; 478 } 479 } 480} 481 482/* 483 * Check to see if the system paniced, pause and then reboot 484 * according to the specified delay. 485 */ 486static void 487shutdown_panic(void *junk, int howto) 488{ 489 int loop; 490 491 if (howto & RB_DUMP) { 492 if (panic_reboot_wait_time != 0) { 493 if (panic_reboot_wait_time != -1) { 494 printf("Automatic reboot in %d seconds - " 495 "press a key on the console to abort\n", 496 panic_reboot_wait_time); 497 for (loop = panic_reboot_wait_time * 10; 498 loop > 0; --loop) { 499 DELAY(1000 * 100); /* 1/10th second */ 500 /* Did user type a key? */ 501 if (cncheckc() != -1) 502 break; 503 } 504 if (!loop) 505 return; 506 } 507 } else { /* zero time specified - reboot NOW */ 508 return; 509 } 510 printf("--> Press a key on the console to reboot,\n"); 511 printf("--> or switch off the system now.\n"); 512 cngetc(); 513 } 514} 515 516/* 517 * Everything done, now reset 518 */ 519static void 520shutdown_reset(void *junk, int howto) 521{ 522 523 printf("Rebooting...\n"); 524 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 525 526 /* 527 * Acquiring smp_ipi_mtx here has a double effect: 528 * - it disables interrupts avoiding CPU0 preemption 529 * by fast handlers (thus deadlocking against other CPUs) 530 * - it avoids deadlocks against smp_rendezvous() or, more 531 * generally, threads busy-waiting, with this spinlock held, 532 * and waiting for responses by threads on other CPUs 533 * (ie. smp_tlb_shootdown()). 534 * 535 * For the !SMP case it just needs to handle the former problem. 536 */ 537#ifdef SMP 538 mtx_lock_spin(&smp_ipi_mtx); 539#else 540 spinlock_enter(); 541#endif 542 543 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 544 cpu_reset(); 545 /* NOTREACHED */ /* assuming reset worked */ 546} 547 548#if defined(WITNESS) || defined(INVARIANTS) 549static int kassert_warn_only = 0; 550#ifdef KDB 551static int kassert_do_kdb = 0; 552#endif 553#ifdef KTR 554static int kassert_do_ktr = 0; 555#endif 556static int kassert_do_log = 1; 557static int kassert_log_pps_limit = 4; 558static int kassert_log_mute_at = 0; 559static int kassert_log_panic_at = 0; 560static int kassert_warnings = 0; 561 562SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options"); 563 564SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RW | CTLFLAG_TUN, 565 &kassert_warn_only, 0, 566 "KASSERT triggers a panic (1) or just a warning (0)"); 567TUNABLE_INT("debug.kassert.warn_only", &kassert_warn_only); 568 569#ifdef KDB 570SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RW | CTLFLAG_TUN, 571 &kassert_do_kdb, 0, "KASSERT will enter the debugger"); 572TUNABLE_INT("debug.kassert.do_kdb", &kassert_do_kdb); 573#endif 574 575#ifdef KTR 576SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RW | CTLFLAG_TUN, 577 &kassert_do_ktr, 0, 578 "KASSERT does a KTR, set this to the KTRMASK you want"); 579TUNABLE_INT("debug.kassert.do_ktr", &kassert_do_ktr); 580#endif 581 582SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RW | CTLFLAG_TUN, 583 &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)"); 584TUNABLE_INT("debug.kassert.do_log", &kassert_do_log); 585 586SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RW | CTLFLAG_TUN, 587 &kassert_warnings, 0, "number of KASSERTs that have been triggered"); 588TUNABLE_INT("debug.kassert.warnings", &kassert_warnings); 589 590SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RW | CTLFLAG_TUN, 591 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic"); 592TUNABLE_INT("debug.kassert.log_panic_at", &kassert_log_panic_at); 593 594SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RW | CTLFLAG_TUN, 595 &kassert_log_pps_limit, 0, "limit number of log messages per second"); 596TUNABLE_INT("debug.kassert.log_pps_limit", &kassert_log_pps_limit); 597 598SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RW | CTLFLAG_TUN, 599 &kassert_log_mute_at, 0, "max number of KASSERTS to log"); 600TUNABLE_INT("debug.kassert.log_mute_at", &kassert_log_mute_at); 601 602static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS); 603 604SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert, 605 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0, 606 kassert_sysctl_kassert, "I", "set to trigger a test kassert"); 607 608static int 609kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS) 610{ 611 int error, i; 612 613 error = sysctl_wire_old_buffer(req, sizeof(int)); 614 if (error == 0) { 615 i = 0; 616 error = sysctl_handle_int(oidp, &i, 0, req); 617 } 618 if (error != 0 || req->newptr == NULL) 619 return (error); 620 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i)); 621 return (0); 622} 623 624/* 625 * Called by KASSERT, this decides if we will panic 626 * or if we will log via printf and/or ktr. 627 */ 628void 629kassert_panic(const char *fmt, ...) 630{ 631 static char buf[256]; 632 va_list ap; 633 634 va_start(ap, fmt); 635 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 636 va_end(ap); 637 638 /* 639 * panic if we're not just warning, or if we've exceeded 640 * kassert_log_panic_at warnings. 641 */ 642 if (!kassert_warn_only || 643 (kassert_log_panic_at > 0 && 644 kassert_warnings >= kassert_log_panic_at)) { 645 va_start(ap, fmt); 646 vpanic(fmt, ap); 647 /* NORETURN */ 648 } 649#ifdef KTR 650 if (kassert_do_ktr) 651 CTR0(ktr_mask, buf); 652#endif /* KTR */ 653 /* 654 * log if we've not yet met the mute limit. 655 */ 656 if (kassert_do_log && 657 (kassert_log_mute_at == 0 || 658 kassert_warnings < kassert_log_mute_at)) { 659 static struct timeval lasterr; 660 static int curerr; 661 662 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) { 663 printf("KASSERT failed: %s\n", buf); 664 kdb_backtrace(); 665 } 666 } 667#ifdef KDB 668 if (kassert_do_kdb) { 669 kdb_enter(KDB_WHY_KASSERT, buf); 670 } 671#endif 672 atomic_add_int(&kassert_warnings, 1); 673} 674#endif 675 676/* 677 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 678 * and then reboots. If we are called twice, then we avoid trying to sync 679 * the disks as this often leads to recursive panics. 680 */ 681void 682panic(const char *fmt, ...) 683{ 684 va_list ap; 685 686 va_start(ap, fmt); 687 vpanic(fmt, ap); 688} 689 690void 691vpanic(const char *fmt, va_list ap) 692{ 693#ifdef SMP 694 cpuset_t other_cpus; 695#endif 696 struct thread *td = curthread; 697 int bootopt, newpanic; 698 static char buf[256]; 699 700 spinlock_enter(); 701 702#ifdef SMP 703 /* 704 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from 705 * concurrently entering panic. Only the winner will proceed 706 * further. 707 */ 708 if (panicstr == NULL && !kdb_active) { 709 other_cpus = all_cpus; 710 CPU_CLR(PCPU_GET(cpuid), &other_cpus); 711 stop_cpus_hard(other_cpus); 712 } 713 714 /* 715 * We set stop_scheduler here and not in the block above, 716 * because we want to ensure that if panic has been called and 717 * stop_scheduler_on_panic is true, then stop_scheduler will 718 * always be set. Even if panic has been entered from kdb. 719 */ 720 td->td_stopsched = 1; 721#endif 722 723 bootopt = RB_AUTOBOOT; 724 newpanic = 0; 725 if (panicstr) 726 bootopt |= RB_NOSYNC; 727 else { 728 bootopt |= RB_DUMP; 729 panicstr = fmt; 730 newpanic = 1; 731 } 732 733 if (newpanic) { 734 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 735 panicstr = buf; 736 cngrab(); 737 printf("panic: %s\n", buf); 738 } else { 739 printf("panic: "); 740 vprintf(fmt, ap); 741 printf("\n"); 742 } 743#ifdef SMP 744 printf("cpuid = %d\n", PCPU_GET(cpuid)); 745#endif 746 747#ifdef KDB 748 if (newpanic && trace_on_panic) 749 kdb_backtrace(); 750 if (debugger_on_panic) 751 kdb_enter(KDB_WHY_PANIC, "panic"); 752#endif 753 /*thread_lock(td); */ 754 td->td_flags |= TDF_INPANIC; 755 /* thread_unlock(td); */ 756 if (!sync_on_panic) 757 bootopt |= RB_NOSYNC; 758 kern_reboot(bootopt); 759} 760 761/* 762 * Support for poweroff delay. 763 * 764 * Please note that setting this delay too short might power off your machine 765 * before the write cache on your hard disk has been flushed, leading to 766 * soft-updates inconsistencies. 767 */ 768#ifndef POWEROFF_DELAY 769# define POWEROFF_DELAY 5000 770#endif 771static int poweroff_delay = POWEROFF_DELAY; 772 773SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 774 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)"); 775 776static void 777poweroff_wait(void *junk, int howto) 778{ 779 780 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 781 return; 782 DELAY(poweroff_delay * 1000); 783} 784 785/* 786 * Some system processes (e.g. syncer) need to be stopped at appropriate 787 * points in their main loops prior to a system shutdown, so that they 788 * won't interfere with the shutdown process (e.g. by holding a disk buf 789 * to cause sync to fail). For each of these system processes, register 790 * shutdown_kproc() as a handler for one of shutdown events. 791 */ 792static int kproc_shutdown_wait = 60; 793SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 794 &kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process"); 795 796void 797kproc_shutdown(void *arg, int howto) 798{ 799 struct proc *p; 800 int error; 801 802 if (panicstr) 803 return; 804 805 p = (struct proc *)arg; 806 printf("Waiting (max %d seconds) for system process `%s' to stop...", 807 kproc_shutdown_wait, p->p_comm); 808 error = kproc_suspend(p, kproc_shutdown_wait * hz); 809 810 if (error == EWOULDBLOCK) 811 printf("timed out\n"); 812 else 813 printf("done\n"); 814} 815 816void 817kthread_shutdown(void *arg, int howto) 818{ 819 struct thread *td; 820 int error; 821 822 if (panicstr) 823 return; 824 825 td = (struct thread *)arg; 826 printf("Waiting (max %d seconds) for system thread `%s' to stop...", 827 kproc_shutdown_wait, td->td_name); 828 error = kthread_suspend(td, kproc_shutdown_wait * hz); 829 830 if (error == EWOULDBLOCK) 831 printf("timed out\n"); 832 else 833 printf("done\n"); 834} 835 836static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)]; 837SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD, 838 dumpdevname, 0, "Device for kernel dumps"); 839 840/* Registration of dumpers */ 841int 842set_dumper(struct dumperinfo *di, const char *devname) 843{ 844 size_t wantcopy; 845 846 if (di == NULL) { 847 bzero(&dumper, sizeof dumper); 848 dumpdevname[0] = '\0'; 849 return (0); 850 } 851 if (dumper.dumper != NULL) 852 return (EBUSY); 853 dumper = *di; 854 wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname)); 855 if (wantcopy >= sizeof(dumpdevname)) { 856 printf("set_dumper: device name truncated from '%s' -> '%s'\n", 857 devname, dumpdevname); 858 } 859 return (0); 860} 861 862/* Call dumper with bounds checking. */ 863int 864dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical, 865 off_t offset, size_t length) 866{ 867 868 if (length != 0 && (offset < di->mediaoffset || 869 offset - di->mediaoffset + length > di->mediasize)) { 870 printf("Attempt to write outside dump device boundaries.\n" 871 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n", 872 (intmax_t)offset, (intmax_t)di->mediaoffset, 873 (uintmax_t)length, (intmax_t)di->mediasize); 874 return (ENOSPC); 875 } 876 return (di->dumper(di->priv, virtual, physical, offset, length)); 877} 878 879void 880mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver, 881 uint64_t dumplen, uint32_t blksz) 882{ 883 884 bzero(kdh, sizeof(*kdh)); 885 strncpy(kdh->magic, magic, sizeof(kdh->magic)); 886 strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture)); 887 kdh->version = htod32(KERNELDUMPVERSION); 888 kdh->architectureversion = htod32(archver); 889 kdh->dumplength = htod64(dumplen); 890 kdh->dumptime = htod64(time_second); 891 kdh->blocksize = htod32(blksz); 892 strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname)); 893 strncpy(kdh->versionstring, version, sizeof(kdh->versionstring)); 894 if (panicstr != NULL) 895 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring)); 896 kdh->parity = kerneldump_parity(kdh); 897} 898