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_show_busybufs.h" 44 #include "opt_sched.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/malloc.h> 59 #include <sys/mount.h> 60 #include <sys/priv.h> 61 #include <sys/proc.h> 62 #include <sys/reboot.h> 63 #include <sys/resourcevar.h> 64 #include <sys/sched.h> 65 #include <sys/smp.h> /* smp_active */ 66 #include <sys/sysctl.h> 67 #include <sys/sysproto.h> 68 69 #include <ddb/ddb.h> 70 71 #include <machine/cpu.h> 72 #include <machine/pcb.h> 73 #include <machine/smp.h> 74 75 #include <security/mac/mac_framework.h> 76 77 #include <vm/vm.h> 78 #include <vm/vm_object.h> 79 #include <vm/vm_page.h> 80 #include <vm/vm_pager.h> 81 #include <vm/swap_pager.h> 82 83 #include <sys/signalvar.h> 84 85 #ifndef PANIC_REBOOT_WAIT_TIME 86 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 87 #endif 88 89 /* 90 * Note that stdarg.h and the ANSI style va_start macro is used for both 91 * ANSI and traditional C compilers. 92 */ 93 #include <machine/stdarg.h> 94 95 #ifdef KDB 96 #ifdef KDB_UNATTENDED 97 int debugger_on_panic = 0; 98 #else 99 int debugger_on_panic = 1; 100 #endif 101 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 102 &debugger_on_panic, 0, "Run debugger on kernel panic"); 103 104 #ifdef KDB_TRACE 105 int trace_on_panic = 1; 106 #else 107 int trace_on_panic = 0; 108 #endif 109 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 110 &trace_on_panic, 0, "Print stack trace on kernel panic"); 111 #endif /* KDB */ 112 113 int sync_on_panic = 0; 114 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 115 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 116 117 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 118 119 /* 120 * Variable panicstr contains argument to first call to panic; used as flag 121 * to indicate that the kernel has already called panic. 122 */ 123 const char *panicstr; 124 125 int dumping; /* system is dumping */ 126 int rebooting; /* system is rebooting */ 127 static struct dumperinfo dumper; /* our selected dumper */ 128 129 /* Context information for dump-debuggers. */ 130 static struct pcb dumppcb; /* Registers. */ 131 static lwpid_t dumptid; /* Thread ID. */ 132 133 static void boot(int) __dead2; 134 static void poweroff_wait(void *, int); 135 static void shutdown_halt(void *junk, int howto); 136 static void shutdown_panic(void *junk, int howto); 137 static void shutdown_reset(void *junk, int howto); 138 139 /* register various local shutdown events */ 140 static void 141 shutdown_conf(void *unused) 142 { 143 144 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, 145 SHUTDOWN_PRI_FIRST); 146 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, 147 SHUTDOWN_PRI_LAST + 100); 148 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, 149 SHUTDOWN_PRI_LAST + 100); 150 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, 151 SHUTDOWN_PRI_LAST + 200); 152 } 153 154 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL); 155 156 /* 157 * The system call that results in a reboot. 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_system_check_reboot(td->td_ucred, uap->opt); 168 #endif 169 if (error == 0) 170 error = priv_check(td, PRIV_REBOOT); 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 /* 235 * Sometimes people have to call this from the kernel debugger. 236 * (if 'panic' can not dump) 237 * Give them a clue as to why they can't dump. 238 */ 239 if (dumper.dumper == NULL) { 240 printf("Cannot dump. Device not defined or unavailable.\n"); 241 return; 242 } 243 244 savectx(&dumppcb); 245 dumptid = curthread->td_tid; 246 dumping++; 247 #ifdef DDB 248 if (textdump_pending) 249 textdump_dumpsys(&dumper); 250 else 251 #endif 252 dumpsys(&dumper); 253 dumping--; 254 } 255 256 static int 257 isbufbusy(struct buf *bp) 258 { 259 if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 && 260 BUF_ISLOCKED(bp)) || 261 ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI)) 262 return (1); 263 return (0); 264 } 265 266 /* 267 * Shutdown the system cleanly to prepare for reboot, halt, or power off. 268 */ 269 static void 270 boot(int howto) 271 { 272 static int first_buf_printf = 1; 273 274 #if defined(SMP) 275 /* 276 * Bind us to CPU 0 so that all shutdown code runs there. Some 277 * systems don't shutdown properly (i.e., ACPI power off) if we 278 * run on another processor. 279 */ 280 thread_lock(curthread); 281 sched_bind(curthread, 0); 282 thread_unlock(curthread); 283 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0")); 284 #endif 285 /* We're in the process of rebooting. */ 286 rebooting = 1; 287 288 /* collect extra flags that shutdown_nice might have set */ 289 howto |= shutdown_howto; 290 291 /* We are out of the debugger now. */ 292 kdb_active = 0; 293 294 /* 295 * Do any callouts that should be done BEFORE syncing the filesystems. 296 */ 297 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 298 299 /* 300 * Now sync filesystems 301 */ 302 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 303 register struct buf *bp; 304 int iter, nbusy, pbusy; 305 #ifndef PREEMPTION 306 int subiter; 307 #endif 308 309 waittime = 0; 310 311 sync(curthread, NULL); 312 313 /* 314 * With soft updates, some buffers that are 315 * written will be remarked as dirty until other 316 * buffers are written. 317 */ 318 for (iter = pbusy = 0; iter < 20; iter++) { 319 nbusy = 0; 320 for (bp = &buf[nbuf]; --bp >= buf; ) 321 if (isbufbusy(bp)) 322 nbusy++; 323 if (nbusy == 0) { 324 if (first_buf_printf) 325 printf("All buffers synced."); 326 break; 327 } 328 if (first_buf_printf) { 329 printf("Syncing disks, buffers remaining... "); 330 first_buf_printf = 0; 331 } 332 printf("%d ", nbusy); 333 if (nbusy < pbusy) 334 iter = 0; 335 pbusy = nbusy; 336 sync(curthread, NULL); 337 338 #ifdef PREEMPTION 339 /* 340 * Drop Giant and spin for a while to allow 341 * interrupt threads to run. 342 */ 343 DROP_GIANT(); 344 DELAY(50000 * iter); 345 PICKUP_GIANT(); 346 #else 347 /* 348 * Drop Giant and context switch several times to 349 * allow interrupt threads to run. 350 */ 351 DROP_GIANT(); 352 for (subiter = 0; subiter < 50 * iter; subiter++) { 353 thread_lock(curthread); 354 mi_switch(SW_VOL, NULL); 355 thread_unlock(curthread); 356 DELAY(1000); 357 } 358 PICKUP_GIANT(); 359 #endif 360 } 361 printf("\n"); 362 /* 363 * Count only busy local buffers to prevent forcing 364 * a fsck if we're just a client of a wedged NFS server 365 */ 366 nbusy = 0; 367 for (bp = &buf[nbuf]; --bp >= buf; ) { 368 if (isbufbusy(bp)) { 369 #if 0 370 /* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */ 371 if (bp->b_dev == NULL) { 372 TAILQ_REMOVE(&mountlist, 373 bp->b_vp->v_mount, mnt_list); 374 continue; 375 } 376 #endif 377 nbusy++; 378 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 379 printf( 380 "%d: bufobj:%p, flags:%0x, blkno:%ld, lblkno:%ld\n", 381 nbusy, bp->b_bufobj, 382 bp->b_flags, (long)bp->b_blkno, 383 (long)bp->b_lblkno); 384 #endif 385 } 386 } 387 if (nbusy) { 388 /* 389 * Failed to sync all blocks. Indicate this and don't 390 * unmount filesystems (thus forcing an fsck on reboot). 391 */ 392 printf("Giving up on %d buffers\n", nbusy); 393 DELAY(5000000); /* 5 seconds */ 394 } else { 395 if (!first_buf_printf) 396 printf("Final sync complete\n"); 397 /* 398 * Unmount filesystems 399 */ 400 if (panicstr == 0) 401 vfs_unmountall(); 402 } 403 swapoff_all(); 404 DELAY(100000); /* wait for console output to finish */ 405 } 406 407 print_uptime(); 408 409 /* 410 * Ok, now do things that assume all filesystem activity has 411 * been completed. 412 */ 413 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 414 415 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping) 416 doadump(); 417 418 /* Now that we're going to really halt the system... */ 419 EVENTHANDLER_INVOKE(shutdown_final, howto); 420 421 for(;;) ; /* safety against shutdown_reset not working */ 422 /* NOTREACHED */ 423 } 424 425 /* 426 * If the shutdown was a clean halt, behave accordingly. 427 */ 428 static void 429 shutdown_halt(void *junk, int howto) 430 { 431 432 if (howto & RB_HALT) { 433 printf("\n"); 434 printf("The operating system has halted.\n"); 435 printf("Please press any key to reboot.\n\n"); 436 switch (cngetc()) { 437 case -1: /* No console, just die */ 438 cpu_halt(); 439 /* NOTREACHED */ 440 default: 441 howto &= ~RB_HALT; 442 break; 443 } 444 } 445 } 446 447 /* 448 * Check to see if the system paniced, pause and then reboot 449 * according to the specified delay. 450 */ 451 static void 452 shutdown_panic(void *junk, int howto) 453 { 454 int loop; 455 456 if (howto & RB_DUMP) { 457 if (PANIC_REBOOT_WAIT_TIME != 0) { 458 if (PANIC_REBOOT_WAIT_TIME != -1) { 459 printf("Automatic reboot in %d seconds - " 460 "press a key on the console to abort\n", 461 PANIC_REBOOT_WAIT_TIME); 462 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 463 loop > 0; --loop) { 464 DELAY(1000 * 100); /* 1/10th second */ 465 /* Did user type a key? */ 466 if (cncheckc() != -1) 467 break; 468 } 469 if (!loop) 470 return; 471 } 472 } else { /* zero time specified - reboot NOW */ 473 return; 474 } 475 printf("--> Press a key on the console to reboot,\n"); 476 printf("--> or switch off the system now.\n"); 477 cngetc(); 478 } 479 } 480 481 /* 482 * Everything done, now reset 483 */ 484 static void 485 shutdown_reset(void *junk, int howto) 486 { 487 488 /* 489 * Disable interrupts on CPU0 in order to avoid fast handlers 490 * to preempt the stopping process and to deadlock against other 491 * CPUs. 492 */ 493 spinlock_enter(); 494 495 printf("Rebooting...\n"); 496 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */ 497 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 498 cpu_reset(); 499 /* NOTREACHED */ /* assuming reset worked */ 500 } 501 502 #ifdef SMP 503 static u_int panic_cpu = NOCPU; 504 #endif 505 506 /* 507 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 508 * and then reboots. If we are called twice, then we avoid trying to sync 509 * the disks as this often leads to recursive panics. 510 */ 511 void 512 panic(const char *fmt, ...) 513 { 514 struct thread *td = curthread; 515 int bootopt, newpanic; 516 va_list ap; 517 static char buf[256]; 518 519 critical_enter(); 520 #ifdef SMP 521 /* 522 * We don't want multiple CPU's to panic at the same time, so we 523 * use panic_cpu as a simple spinlock. We have to keep checking 524 * panic_cpu if we are spinning in case the panic on the first 525 * CPU is canceled. 526 */ 527 if (panic_cpu != PCPU_GET(cpuid)) 528 while (atomic_cmpset_int(&panic_cpu, NOCPU, 529 PCPU_GET(cpuid)) == 0) 530 while (panic_cpu != NOCPU) 531 ; /* nothing */ 532 #endif 533 534 bootopt = RB_AUTOBOOT | RB_DUMP; 535 newpanic = 0; 536 if (panicstr) 537 bootopt |= RB_NOSYNC; 538 else { 539 panicstr = fmt; 540 newpanic = 1; 541 } 542 543 va_start(ap, fmt); 544 if (newpanic) { 545 (void)vsnprintf(buf, sizeof(buf), fmt, ap); 546 panicstr = buf; 547 printf("panic: %s\n", buf); 548 } else { 549 printf("panic: "); 550 vprintf(fmt, ap); 551 printf("\n"); 552 } 553 va_end(ap); 554 #ifdef SMP 555 printf("cpuid = %d\n", PCPU_GET(cpuid)); 556 #endif 557 558 #ifdef KDB 559 if (newpanic && trace_on_panic) 560 kdb_backtrace(); 561 if (debugger_on_panic) 562 kdb_enter(KDB_WHY_PANIC, "panic"); 563 #ifdef RESTARTABLE_PANICS 564 /* See if the user aborted the panic, in which case we continue. */ 565 if (panicstr == NULL) { 566 #ifdef SMP 567 atomic_store_rel_int(&panic_cpu, NOCPU); 568 #endif 569 return; 570 } 571 #endif 572 #endif 573 /*thread_lock(td); */ 574 td->td_flags |= TDF_INPANIC; 575 /* thread_unlock(td); */ 576 if (!sync_on_panic) 577 bootopt |= RB_NOSYNC; 578 critical_exit(); 579 boot(bootopt); 580 } 581 582 /* 583 * Support for poweroff delay. 584 */ 585 #ifndef POWEROFF_DELAY 586 # define POWEROFF_DELAY 5000 587 #endif 588 static int poweroff_delay = POWEROFF_DELAY; 589 590 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 591 &poweroff_delay, 0, ""); 592 593 static void 594 poweroff_wait(void *junk, int howto) 595 { 596 597 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0) 598 return; 599 DELAY(poweroff_delay * 1000); 600 } 601 602 /* 603 * Some system processes (e.g. syncer) need to be stopped at appropriate 604 * points in their main loops prior to a system shutdown, so that they 605 * won't interfere with the shutdown process (e.g. by holding a disk buf 606 * to cause sync to fail). For each of these system processes, register 607 * shutdown_kproc() as a handler for one of shutdown events. 608 */ 609 static int kproc_shutdown_wait = 60; 610 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 611 &kproc_shutdown_wait, 0, ""); 612 613 void 614 kproc_shutdown(void *arg, int howto) 615 { 616 struct proc *p; 617 char procname[MAXCOMLEN + 1]; 618 int error; 619 620 if (panicstr) 621 return; 622 623 p = (struct proc *)arg; 624 strlcpy(procname, p->p_comm, sizeof(procname)); 625 printf("Waiting (max %d seconds) for system process `%s' to stop...", 626 kproc_shutdown_wait, procname); 627 error = kproc_suspend(p, kproc_shutdown_wait * hz); 628 629 if (error == EWOULDBLOCK) 630 printf("timed out\n"); 631 else 632 printf("done\n"); 633 } 634 635 void 636 kthread_shutdown(void *arg, int howto) 637 { 638 struct thread *td; 639 char procname[MAXCOMLEN + 1]; 640 int error; 641 642 if (panicstr) 643 return; 644 645 td = (struct thread *)arg; 646 strlcpy(procname, td->td_name, sizeof(procname)); 647 printf("Waiting (max %d seconds) for system thread `%s' to stop...", 648 kproc_shutdown_wait, procname); 649 error = kthread_suspend(td, kproc_shutdown_wait * hz); 650 651 if (error == EWOULDBLOCK) 652 printf("timed out\n"); 653 else 654 printf("done\n"); 655 } 656 657 /* Registration of dumpers */ 658 int 659 set_dumper(struct dumperinfo *di) 660 { 661 662 if (di == NULL) { 663 bzero(&dumper, sizeof dumper); 664 return (0); 665 } 666 if (dumper.dumper != NULL) 667 return (EBUSY); 668 dumper = *di; 669 return (0); 670 } 671 672 /* Call dumper with bounds checking. */ 673 int 674 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical, 675 off_t offset, size_t length) 676 { 677 678 if (length != 0 && (offset < di->mediaoffset || 679 offset - di->mediaoffset + length > di->mediasize)) { 680 printf("Attempt to write outside dump device boundaries.\n"); 681 return (ENXIO); 682 } 683 return (di->dumper(di->priv, virtual, physical, offset, length)); 684 } 685 686 void 687 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver, 688 uint64_t dumplen, uint32_t blksz) 689 { 690 691 bzero(kdh, sizeof(*kdh)); 692 strncpy(kdh->magic, magic, sizeof(kdh->magic)); 693 strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture)); 694 kdh->version = htod32(KERNELDUMPVERSION); 695 kdh->architectureversion = htod32(archver); 696 kdh->dumplength = htod64(dumplen); 697 kdh->dumptime = htod64(time_second); 698 kdh->blocksize = htod32(blksz); 699 strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname)); 700 strncpy(kdh->versionstring, version, sizeof(kdh->versionstring)); 701 if (panicstr != NULL) 702 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring)); 703 kdh->parity = kerneldump_parity(kdh); 704 } 705