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: src/sys/kern/kern_shutdown.c,v 1.72.2.12 2002/02/21 19:15:10 dillon Exp $ 40 * $DragonFly: src/sys/kern/kern_shutdown.c,v 1.60 2007/09/21 09:07:03 swildner Exp $ 41 */ 42 43 #include "opt_ddb.h" 44 #include "opt_ddb_trace.h" 45 #include "opt_hw_wdog.h" 46 #include "opt_panic.h" 47 #include "opt_show_busybufs.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/eventhandler.h> 52 #include <sys/buf.h> 53 #include <sys/diskslice.h> 54 #include <sys/reboot.h> 55 #include <sys/proc.h> 56 #include <sys/fcntl.h> /* FREAD */ 57 #include <sys/stat.h> /* S_IFCHR */ 58 #include <sys/vnode.h> 59 #include <sys/kernel.h> 60 #include <sys/kthread.h> 61 #include <sys/malloc.h> 62 #include <sys/mount.h> 63 #include <sys/queue.h> 64 #include <sys/sysctl.h> 65 #include <sys/vkernel.h> 66 #include <sys/conf.h> 67 #include <sys/sysproto.h> 68 #include <sys/device.h> 69 #include <sys/cons.h> 70 #include <sys/shm.h> 71 #include <sys/kern_syscall.h> 72 #include <vm/vm_map.h> 73 #include <vm/pmap.h> 74 75 #include <sys/thread2.h> 76 #include <sys/buf2.h> 77 78 #include <machine/pcb.h> 79 #include <machine/clock.h> 80 #include <machine/md_var.h> 81 #include <machine/smp.h> /* smp_active_mask, cpuid */ 82 #include <machine/vmparam.h> 83 84 #include <sys/signalvar.h> 85 86 #ifndef PANIC_REBOOT_WAIT_TIME 87 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 88 #endif 89 90 /* 91 * Note that stdarg.h and the ANSI style va_start macro is used for both 92 * ANSI and traditional C compilers. We use the machine version to stay 93 * within the confines of the kernel header files. 94 */ 95 #include <machine/stdarg.h> 96 97 #ifdef DDB 98 #ifdef DDB_UNATTENDED 99 int debugger_on_panic = 0; 100 #else 101 int debugger_on_panic = 1; 102 #endif 103 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 104 &debugger_on_panic, 0, "Run debugger on kernel panic"); 105 106 extern void db_print_backtrace(void); 107 108 #ifdef DDB_TRACE 109 int trace_on_panic = 1; 110 #else 111 int trace_on_panic = 0; 112 #endif 113 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 114 &trace_on_panic, 0, "Print stack trace on kernel panic"); 115 #endif 116 117 static int sync_on_panic = 1; 118 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 119 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 120 121 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 122 123 #ifdef HW_WDOG 124 /* 125 * If there is a hardware watchdog, point this at the function needed to 126 * hold it off. 127 * It's needed when the kernel needs to do some lengthy operations. 128 * e.g. in wd.c when dumping core.. It's most annoying to have 129 * your precious core-dump only half written because the wdog kicked in. 130 */ 131 watchdog_tickle_fn wdog_tickler = NULL; 132 #endif /* HW_WDOG */ 133 134 /* 135 * Variable panicstr contains argument to first call to panic; used as flag 136 * to indicate that the kernel has already called panic. 137 */ 138 const char *panicstr; 139 140 int dumping; /* system is dumping */ 141 #ifdef SMP 142 u_int panic_cpu_interlock; /* panic interlock */ 143 globaldata_t panic_cpu_gd; /* which cpu took the panic */ 144 #endif 145 146 int bootverbose = 0; /* note: assignment to force non-bss */ 147 int cold = 1; /* note: assignment to force non-bss */ 148 int dumplo; /* OBSOLETE - savecore compat */ 149 u_int64_t dumplo64; 150 151 static void boot (int) __dead2; 152 static void dumpsys (void); 153 static int setdumpdev (cdev_t dev); 154 static void poweroff_wait (void *, int); 155 static void print_uptime (void); 156 static void shutdown_halt (void *junk, int howto); 157 static void shutdown_panic (void *junk, int howto); 158 static void shutdown_reset (void *junk, int howto); 159 static int shutdown_busycount1(struct buf *bp, void *info); 160 static int shutdown_busycount2(struct buf *bp, void *info); 161 static void shutdown_cleanup_proc(struct proc *p); 162 163 /* register various local shutdown events */ 164 static void 165 shutdown_conf(void *unused) 166 { 167 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST); 168 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100); 169 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100); 170 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200); 171 } 172 173 SYSINIT(shutdown_conf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, shutdown_conf, NULL) 174 175 /* ARGSUSED */ 176 177 /* 178 * The system call that results in a reboot 179 */ 180 int 181 sys_reboot(struct reboot_args *uap) 182 { 183 struct thread *td = curthread; 184 int error; 185 186 if ((error = suser(td))) 187 return (error); 188 189 boot(uap->opt); 190 return (0); 191 } 192 193 /* 194 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 195 */ 196 static int shutdown_howto = 0; 197 198 void 199 shutdown_nice(int howto) 200 { 201 shutdown_howto = howto; 202 203 /* Send a signal to init(8) and have it shutdown the world */ 204 if (initproc != NULL) { 205 ksignal(initproc, SIGINT); 206 } else { 207 /* No init(8) running, so simply reboot */ 208 boot(RB_NOSYNC); 209 } 210 return; 211 } 212 static int waittime = -1; 213 static struct thread *dumpthread; 214 static struct pcb dumppcb; 215 216 static void 217 print_uptime(void) 218 { 219 int f; 220 struct timespec ts; 221 222 getnanouptime(&ts); 223 kprintf("Uptime: "); 224 f = 0; 225 if (ts.tv_sec >= 86400) { 226 kprintf("%ldd", ts.tv_sec / 86400); 227 ts.tv_sec %= 86400; 228 f = 1; 229 } 230 if (f || ts.tv_sec >= 3600) { 231 kprintf("%ldh", ts.tv_sec / 3600); 232 ts.tv_sec %= 3600; 233 f = 1; 234 } 235 if (f || ts.tv_sec >= 60) { 236 kprintf("%ldm", ts.tv_sec / 60); 237 ts.tv_sec %= 60; 238 f = 1; 239 } 240 kprintf("%lds\n", ts.tv_sec); 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 * Get rid of any user scheduler baggage and then give 253 * us a high priority. 254 */ 255 if (curthread->td_release) 256 curthread->td_release(curthread); 257 lwkt_setpri_self(TDPRI_MAX); 258 259 /* collect extra flags that shutdown_nice might have set */ 260 howto |= shutdown_howto; 261 262 #ifdef SMP 263 /* 264 * We really want to shutdown on the BSP. Subsystems such as ACPI 265 * can't power-down the box otherwise. 266 */ 267 if (smp_active_mask > 1) { 268 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid); 269 } 270 if (panicstr == NULL && mycpu->gd_cpuid != 0) { 271 kprintf("Switching to cpu #0 for shutdown\n"); 272 lwkt_setcpu_self(globaldata_find(0)); 273 } 274 #endif 275 /* 276 * Do any callouts that should be done BEFORE syncing the filesystems. 277 */ 278 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 279 280 /* 281 * Try to get rid of any remaining FS references. The calling 282 * process, proc0, and init may still hold references. The 283 * VFS cache subsystem may still hold a root reference to root. 284 * 285 * XXX this needs work. We really need to SIGSTOP all remaining 286 * processes in order to avoid blowups due to proc0's filesystem 287 * references going away. For now just make sure that the init 288 * process is stopped. 289 */ 290 if (panicstr == NULL) { 291 shutdown_cleanup_proc(curproc); 292 shutdown_cleanup_proc(&proc0); 293 if (initproc) { 294 if (initproc != curproc) { 295 ksignal(initproc, SIGSTOP); 296 tsleep(boot, 0, "shutdn", hz / 20); 297 } 298 shutdown_cleanup_proc(initproc); 299 } 300 vfs_cache_setroot(NULL, NULL); 301 } 302 303 /* 304 * Now sync filesystems 305 */ 306 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 307 int iter, nbusy, pbusy; 308 309 waittime = 0; 310 kprintf("\nsyncing disks... "); 311 312 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 313 314 /* 315 * With soft updates, some buffers that are 316 * written will be remarked as dirty until other 317 * buffers are written. 318 */ 319 for (iter = pbusy = 0; iter < 20; iter++) { 320 nbusy = scan_all_buffers(shutdown_busycount1, NULL); 321 if (nbusy == 0) 322 break; 323 kprintf("%d ", nbusy); 324 if (nbusy < pbusy) 325 iter = 0; 326 pbusy = nbusy; 327 /* 328 * XXX: 329 * Process soft update work queue if buffers don't sync 330 * after 6 iterations by permitting the syncer to run. 331 */ 332 if (iter > 5 && bioops.io_sync) 333 (*bioops.io_sync)(NULL); 334 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 335 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1); 336 } 337 kprintf("\n"); 338 /* 339 * Count only busy local buffers to prevent forcing 340 * a fsck if we're just a client of a wedged NFS server 341 */ 342 nbusy = scan_all_buffers(shutdown_busycount2, NULL); 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 kprintf("giving up on %d buffers\n", nbusy); 349 #ifdef DDB 350 Debugger("busy buffer problem"); 351 #endif /* DDB */ 352 tsleep(boot, 0, "shutdn", hz * 5 + 1); 353 } else { 354 kprintf("done\n"); 355 /* 356 * Unmount filesystems 357 */ 358 if (panicstr == NULL) 359 vfs_unmountall(); 360 } 361 tsleep(boot, 0, "shutdn", hz / 10 + 1); 362 } 363 364 print_uptime(); 365 366 /* 367 * Dump before doing post_sync shutdown ops 368 */ 369 crit_enter(); 370 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) 371 dumpsys(); 372 373 /* 374 * Ok, now do things that assume all filesystem activity has 375 * been completed. This will also call the device shutdown 376 * methods. 377 */ 378 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 379 380 /* Now that we're going to really halt the system... */ 381 EVENTHANDLER_INVOKE(shutdown_final, howto); 382 383 for(;;) ; /* safety against shutdown_reset not working */ 384 /* NOTREACHED */ 385 } 386 387 static int 388 shutdown_busycount1(struct buf *bp, void *info) 389 { 390 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0) 391 return(1); 392 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) 393 return (1); 394 return (0); 395 } 396 397 static int 398 shutdown_busycount2(struct buf *bp, void *info) 399 { 400 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) || 401 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 402 /* 403 * Only count buffers undergoing write I/O 404 * on the related vnode. 405 */ 406 if (bp->b_vp == NULL || 407 bp->b_vp->v_track_write.bk_active == 0) { 408 return (0); 409 } 410 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 411 kprintf( 412 "%p dev:?, flags:%08x, loffset:%lld, doffset:%lld\n", 413 bp, 414 bp->b_flags, bp->b_loffset, 415 bp->b_bio2.bio_offset); 416 #endif 417 return(1); 418 } 419 return(0); 420 } 421 422 /* 423 * If the shutdown was a clean halt, behave accordingly. 424 */ 425 static void 426 shutdown_halt(void *junk, int howto) 427 { 428 if (howto & RB_HALT) { 429 kprintf("\n"); 430 kprintf("The operating system has halted.\n"); 431 #ifdef _KERNEL_VIRTUAL 432 cpu_halt(); 433 #else 434 kprintf("Please press any key to reboot.\n\n"); 435 switch (cngetc()) { 436 case -1: /* No console, just die */ 437 cpu_halt(); 438 /* NOTREACHED */ 439 default: 440 howto &= ~RB_HALT; 441 break; 442 } 443 #endif 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 kprintf("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 kprintf("--> Press a key on the console to reboot,\n"); 476 kprintf("--> 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 kprintf("Rebooting...\n"); 488 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */ 489 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 490 cpu_reset(); 491 /* NOTREACHED */ /* assuming reset worked */ 492 } 493 494 /* 495 * Try to remove FS references in the specified process. This function 496 * is used during shutdown 497 */ 498 static 499 void 500 shutdown_cleanup_proc(struct proc *p) 501 { 502 struct filedesc *fdp; 503 struct vmspace *vm; 504 505 if (p == NULL) 506 return; 507 if ((fdp = p->p_fd) != NULL) { 508 kern_closefrom(0); 509 if (fdp->fd_cdir) { 510 cache_drop(&fdp->fd_ncdir); 511 vrele(fdp->fd_cdir); 512 fdp->fd_cdir = NULL; 513 } 514 if (fdp->fd_rdir) { 515 cache_drop(&fdp->fd_nrdir); 516 vrele(fdp->fd_rdir); 517 fdp->fd_rdir = NULL; 518 } 519 if (fdp->fd_jdir) { 520 cache_drop(&fdp->fd_njdir); 521 vrele(fdp->fd_jdir); 522 fdp->fd_jdir = NULL; 523 } 524 } 525 if (p->p_vkernel) 526 vkernel_exit(p); 527 if (p->p_textvp) { 528 vrele(p->p_textvp); 529 p->p_textvp = NULL; 530 } 531 vm = p->p_vmspace; 532 if (vm != NULL) { 533 pmap_remove_pages(vmspace_pmap(vm), 534 VM_MIN_USER_ADDRESS, 535 VM_MAX_USER_ADDRESS); 536 vm_map_remove(&vm->vm_map, 537 VM_MIN_USER_ADDRESS, 538 VM_MAX_USER_ADDRESS); 539 } 540 } 541 542 /* 543 * Magic number for savecore 544 * 545 * exported (symorder) and used at least by savecore(8) 546 * 547 * Mark it as used so that gcc doesn't optimize it away. 548 */ 549 __attribute__((__used__)) 550 static u_long const dumpmag = 0x8fca0101UL; 551 552 static int dumpsize = 0; /* also for savecore */ 553 554 static int dodump = 1; 555 556 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, 557 "Try to perform coredump on kernel panic"); 558 559 static int 560 setdumpdev(cdev_t dev) 561 { 562 struct partinfo pinfo; 563 u_int64_t newdumplo; 564 int error; 565 int doopen; 566 567 if (dev == NULL) { 568 dumpdev = dev; 569 return (0); 570 } 571 bzero(&pinfo, sizeof(pinfo)); 572 573 /* 574 * We have to open the device before we can perform ioctls on it, 575 * or the slice/label data may not be present. Device opens are 576 * usually tracked by specfs, but the dump device can be set in 577 * early boot and may not be open so this is somewhat of a hack. 578 */ 579 doopen = (dev->si_sysref.refcnt == 1); 580 if (doopen) { 581 error = dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred); 582 if (error) 583 return (error); 584 } 585 error = dev_dioctl(dev, DIOCGPART, (void *)&pinfo, 0, proc0.p_ucred); 586 if (doopen) 587 dev_dclose(dev, FREAD, S_IFCHR); 588 if (error || pinfo.media_blocks == 0 || pinfo.media_blksize == 0) 589 return (ENXIO); 590 591 newdumplo = pinfo.media_blocks - 592 ((u_int64_t)Maxmem * PAGE_SIZE / DEV_BSIZE); 593 if ((int64_t)newdumplo < (int64_t)pinfo.reserved_blocks) 594 return (ENOSPC); 595 dumpdev = dev; 596 dumplo64 = newdumplo; 597 return (0); 598 } 599 600 601 /* ARGSUSED */ 602 static void dump_conf (void *dummy); 603 static void 604 dump_conf(void *dummy) 605 { 606 char *path; 607 cdev_t dev; 608 609 path = kmalloc(MNAMELEN, M_TEMP, M_WAITOK); 610 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) { 611 dev = kgetdiskbyname(path); 612 if (dev != NULL) 613 dumpdev = dev; 614 } 615 kfree(path, M_TEMP); 616 if (setdumpdev(dumpdev) != 0) 617 dumpdev = NULL; 618 } 619 620 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL) 621 622 static int 623 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS) 624 { 625 int error; 626 udev_t ndumpdev; 627 628 ndumpdev = dev2udev(dumpdev); 629 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req); 630 if (error == 0 && req->newptr != NULL) 631 error = setdumpdev(udev2dev(ndumpdev, 0)); 632 return (error); 633 } 634 635 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW, 636 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,udev_t", ""); 637 638 /* 639 * Doadump comes here after turning off memory management and 640 * getting on the dump stack, either when called above, or by 641 * the auto-restart code. 642 */ 643 static void 644 dumpsys(void) 645 { 646 int error; 647 648 savectx(&dumppcb); 649 dumpthread = curthread; 650 if (dumping++) { 651 kprintf("Dump already in progress, bailing...\n"); 652 return; 653 } 654 if (!dodump) 655 return; 656 if (dumpdev == NULL) 657 return; 658 dumpsize = Maxmem; 659 kprintf("\ndumping to dev %s, blockno %lld\n", 660 devtoname(dumpdev), dumplo64); 661 kprintf("dump "); 662 error = dev_ddump(dumpdev); 663 if (error == 0) { 664 kprintf("succeeded\n"); 665 return; 666 } 667 kprintf("failed, reason: "); 668 switch (error) { 669 case ENOSYS: 670 case ENODEV: 671 kprintf("device doesn't support a dump routine\n"); 672 break; 673 674 case ENXIO: 675 kprintf("device bad\n"); 676 break; 677 678 case EFAULT: 679 kprintf("device not ready\n"); 680 break; 681 682 case EINVAL: 683 kprintf("area improper\n"); 684 break; 685 686 case EIO: 687 kprintf("i/o error\n"); 688 break; 689 690 case EINTR: 691 kprintf("aborted from console\n"); 692 break; 693 694 default: 695 kprintf("unknown, error = %d\n", error); 696 break; 697 } 698 } 699 700 int 701 dumpstatus(vm_offset_t addr, off_t count) 702 { 703 int c; 704 705 if (addr % (1024 * 1024) == 0) { 706 #ifdef HW_WDOG 707 if (wdog_tickler) 708 (*wdog_tickler)(); 709 #endif 710 kprintf("%ld ", (long)(count / (1024 * 1024))); 711 } 712 713 if ((c = cncheckc()) == 0x03) 714 return -1; 715 else if (c != -1) 716 kprintf("[CTRL-C to abort] "); 717 718 return 0; 719 } 720 721 /* 722 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 723 * and then reboots. If we are called twice, then we avoid trying to sync 724 * the disks as this often leads to recursive panics. 725 */ 726 void 727 panic(const char *fmt, ...) 728 { 729 int bootopt, newpanic; 730 __va_list ap; 731 static char buf[256]; 732 733 #ifdef SMP 734 /* 735 * If a panic occurs on multiple cpus before the first is able to 736 * halt the other cpus, only one cpu is allowed to take the panic. 737 * Attempt to be verbose about this situation but if the kprintf() 738 * itself panics don't let us overrun the kernel stack. 739 * 740 * Be very nasty about descheduling our thread at the lowest 741 * level possible in an attempt to freeze the thread without 742 * inducing further panics. 743 * 744 * Bumping gd_trap_nesting_level will also bypass assertions in 745 * lwkt_switch() and allow us to switch away even if we are a 746 * FAST interrupt or IPI. 747 */ 748 if (atomic_poll_acquire_int(&panic_cpu_interlock)) { 749 panic_cpu_gd = mycpu; 750 } else if (panic_cpu_gd != mycpu) { 751 crit_enter(); 752 ++mycpu->gd_trap_nesting_level; 753 if (mycpu->gd_trap_nesting_level < 25) { 754 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n", 755 mycpu->gd_cpuid, curthread); 756 } 757 curthread->td_release = NULL; /* be a grinch */ 758 for (;;) { 759 lwkt_deschedule_self(curthread); 760 lwkt_switch(); 761 } 762 /* NOT REACHED */ 763 /* --mycpu->gd_trap_nesting_level */ 764 /* crit_exit() */ 765 } 766 #endif 767 bootopt = RB_AUTOBOOT | RB_DUMP; 768 if (sync_on_panic == 0) 769 bootopt |= RB_NOSYNC; 770 newpanic = 0; 771 if (panicstr) 772 bootopt |= RB_NOSYNC; 773 else { 774 panicstr = fmt; 775 newpanic = 1; 776 } 777 778 __va_start(ap, fmt); 779 kvsnprintf(buf, sizeof(buf), fmt, ap); 780 if (panicstr == fmt) 781 panicstr = buf; 782 __va_end(ap); 783 kprintf("panic: %s\n", buf); 784 #ifdef SMP 785 /* two separate prints in case of an unmapped page and trap */ 786 kprintf("mp_lock = %08x; ", mp_lock); 787 kprintf("cpuid = %d\n", mycpu->gd_cpuid); 788 #endif 789 790 #if defined(DDB) 791 if (newpanic && trace_on_panic) 792 db_print_backtrace(); 793 if (debugger_on_panic) 794 Debugger("panic"); 795 #endif 796 boot(bootopt); 797 } 798 799 /* 800 * Support for poweroff delay. 801 */ 802 #ifndef POWEROFF_DELAY 803 # define POWEROFF_DELAY 5000 804 #endif 805 static int poweroff_delay = POWEROFF_DELAY; 806 807 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 808 &poweroff_delay, 0, ""); 809 810 static void 811 poweroff_wait(void *junk, int howto) 812 { 813 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0) 814 return; 815 DELAY(poweroff_delay * 1000); 816 } 817 818 /* 819 * Some system processes (e.g. syncer) need to be stopped at appropriate 820 * points in their main loops prior to a system shutdown, so that they 821 * won't interfere with the shutdown process (e.g. by holding a disk buf 822 * to cause sync to fail). For each of these system processes, register 823 * shutdown_kproc() as a handler for one of shutdown events. 824 */ 825 static int kproc_shutdown_wait = 60; 826 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 827 &kproc_shutdown_wait, 0, ""); 828 829 void 830 shutdown_kproc(void *arg, int howto) 831 { 832 struct thread *td; 833 struct proc *p; 834 int error; 835 836 if (panicstr) 837 return; 838 839 td = (struct thread *)arg; 840 if ((p = td->td_proc) != NULL) { 841 kprintf("Waiting (max %d seconds) for system process `%s' to stop...", 842 kproc_shutdown_wait, p->p_comm); 843 } else { 844 kprintf("Waiting (max %d seconds) for system thread %s to stop...", 845 kproc_shutdown_wait, td->td_comm); 846 } 847 error = suspend_kproc(td, kproc_shutdown_wait * hz); 848 849 if (error == EWOULDBLOCK) 850 kprintf("timed out\n"); 851 else 852 kprintf("stopped\n"); 853 } 854