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 1.47 2007/01/05 22:16:28 dillon 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/disklabel.h> 54 #include <sys/reboot.h> 55 #include <sys/proc.h> 56 #include <sys/vnode.h> 57 #include <sys/kernel.h> 58 #include <sys/kthread.h> 59 #include <sys/malloc.h> 60 #include <sys/mount.h> 61 #include <sys/queue.h> 62 #include <sys/sysctl.h> 63 #include <sys/vkernel.h> 64 #include <sys/conf.h> 65 #include <sys/sysproto.h> 66 #include <sys/device.h> 67 #include <sys/cons.h> 68 #include <sys/shm.h> 69 #include <sys/kern_syscall.h> 70 #include <vm/vm_map.h> 71 #include <vm/pmap.h> 72 73 #include <sys/thread2.h> 74 #include <sys/buf2.h> 75 76 #include <machine/pcb.h> 77 #include <machine/clock.h> 78 #include <machine/md_var.h> 79 #include <machine/smp.h> /* smp_active_mask, cpuid */ 80 #include <machine/vmparam.h> 81 82 #include <sys/signalvar.h> 83 84 #ifndef PANIC_REBOOT_WAIT_TIME 85 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 86 #endif 87 88 /* 89 * Note that stdarg.h and the ANSI style va_start macro is used for both 90 * ANSI and traditional C compilers. We use the machine version to stay 91 * within the confines of the kernel header files. 92 */ 93 #include <machine/stdarg.h> 94 95 #ifdef DDB 96 #ifdef DDB_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 extern void db_print_backtrace(void); 105 106 #ifdef DDB_TRACE 107 int trace_on_panic = 1; 108 #else 109 int trace_on_panic = 0; 110 #endif 111 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 112 &trace_on_panic, 0, "Print stack trace on kernel panic"); 113 #endif 114 115 static int sync_on_panic = 1; 116 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 117 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 118 119 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 120 121 #ifdef HW_WDOG 122 /* 123 * If there is a hardware watchdog, point this at the function needed to 124 * hold it off. 125 * It's needed when the kernel needs to do some lengthy operations. 126 * e.g. in wd.c when dumping core.. It's most annoying to have 127 * your precious core-dump only half written because the wdog kicked in. 128 */ 129 watchdog_tickle_fn wdog_tickler = NULL; 130 #endif /* HW_WDOG */ 131 132 /* 133 * Variable panicstr contains argument to first call to panic; used as flag 134 * to indicate that the kernel has already called panic. 135 */ 136 const char *panicstr; 137 138 int dumping; /* system is dumping */ 139 #ifdef SMP 140 u_int panic_cpu_interlock; /* panic interlock */ 141 globaldata_t panic_cpu_gd; /* which cpu took the panic */ 142 #endif 143 144 int bootverbose = 0; /* note: assignment to force non-bss */ 145 int cold = 1; /* note: assignment to force non-bss */ 146 long dumplo; 147 148 static void boot (int) __dead2; 149 static void dumpsys (void); 150 static int setdumpdev (cdev_t dev); 151 static void poweroff_wait (void *, int); 152 static void print_uptime (void); 153 static void shutdown_halt (void *junk, int howto); 154 static void shutdown_panic (void *junk, int howto); 155 static void shutdown_reset (void *junk, int howto); 156 static int shutdown_busycount1(struct buf *bp, void *info); 157 static int shutdown_busycount2(struct buf *bp, void *info); 158 static void shutdown_cleanup_proc(struct proc *p); 159 160 /* register various local shutdown events */ 161 static void 162 shutdown_conf(void *unused) 163 { 164 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST); 165 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100); 166 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100); 167 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200); 168 } 169 170 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL) 171 172 /* ARGSUSED */ 173 174 /* 175 * The system call that results in a reboot 176 */ 177 int 178 sys_reboot(struct reboot_args *uap) 179 { 180 struct thread *td = curthread; 181 int error; 182 183 if ((error = suser(td))) 184 return (error); 185 186 boot(uap->opt); 187 return (0); 188 } 189 190 /* 191 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 192 */ 193 static int shutdown_howto = 0; 194 195 void 196 shutdown_nice(int howto) 197 { 198 shutdown_howto = howto; 199 200 /* Send a signal to init(8) and have it shutdown the world */ 201 if (initproc != NULL) { 202 ksignal(initproc, SIGINT); 203 } else { 204 /* No init(8) running, so simply reboot */ 205 boot(RB_NOSYNC); 206 } 207 return; 208 } 209 static int waittime = -1; 210 static struct thread *dumpthread; 211 static struct pcb dumppcb; 212 213 static void 214 print_uptime(void) 215 { 216 int f; 217 struct timespec ts; 218 219 getnanouptime(&ts); 220 kprintf("Uptime: "); 221 f = 0; 222 if (ts.tv_sec >= 86400) { 223 kprintf("%ldd", ts.tv_sec / 86400); 224 ts.tv_sec %= 86400; 225 f = 1; 226 } 227 if (f || ts.tv_sec >= 3600) { 228 kprintf("%ldh", ts.tv_sec / 3600); 229 ts.tv_sec %= 3600; 230 f = 1; 231 } 232 if (f || ts.tv_sec >= 60) { 233 kprintf("%ldm", ts.tv_sec / 60); 234 ts.tv_sec %= 60; 235 f = 1; 236 } 237 kprintf("%lds\n", ts.tv_sec); 238 } 239 240 /* 241 * Go through the rigmarole of shutting down.. 242 * this used to be in machdep.c but I'll be dammned if I could see 243 * anything machine dependant in it. 244 */ 245 static void 246 boot(int howto) 247 { 248 /* 249 * Get rid of any user scheduler baggage and then give 250 * us a high priority. 251 */ 252 if (curthread->td_release) 253 curthread->td_release(curthread); 254 lwkt_setpri_self(TDPRI_MAX); 255 256 /* collect extra flags that shutdown_nice might have set */ 257 howto |= shutdown_howto; 258 259 #ifdef SMP 260 /* 261 * We really want to shutdown on the BSP. Subsystems such as ACPI 262 * can't power-down the box otherwise. 263 */ 264 if (smp_active_mask > 1) { 265 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid); 266 } 267 if (panicstr == NULL && mycpu->gd_cpuid != 0) { 268 kprintf("Switching to cpu #0 for shutdown\n"); 269 lwkt_setcpu_self(globaldata_find(0)); 270 } 271 #endif 272 /* 273 * Do any callouts that should be done BEFORE syncing the filesystems. 274 */ 275 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 276 277 /* 278 * Try to get rid of any remaining FS references. The calling 279 * process, proc0, and init may still hold references. The 280 * VFS cache subsystem may still hold a root reference to root. 281 */ 282 if (panicstr == NULL) { 283 shutdown_cleanup_proc(curproc); 284 shutdown_cleanup_proc(&proc0); 285 if (initproc) 286 shutdown_cleanup_proc(initproc); 287 vfs_cache_setroot(NULL, NULL); 288 } 289 290 /* 291 * Now sync filesystems 292 */ 293 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 294 int iter, nbusy, pbusy; 295 296 waittime = 0; 297 kprintf("\nsyncing disks... "); 298 299 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 300 301 /* 302 * With soft updates, some buffers that are 303 * written will be remarked as dirty until other 304 * buffers are written. 305 */ 306 for (iter = pbusy = 0; iter < 20; iter++) { 307 nbusy = scan_all_buffers(shutdown_busycount1, NULL); 308 if (nbusy == 0) 309 break; 310 kprintf("%d ", nbusy); 311 if (nbusy < pbusy) 312 iter = 0; 313 pbusy = nbusy; 314 /* 315 * XXX: 316 * Process soft update work queue if buffers don't sync 317 * after 6 iterations by permitting the syncer to run. 318 */ 319 if (iter > 5 && bioops.io_sync) 320 (*bioops.io_sync)(NULL); 321 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 322 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1); 323 } 324 kprintf("\n"); 325 /* 326 * Count only busy local buffers to prevent forcing 327 * a fsck if we're just a client of a wedged NFS server 328 */ 329 nbusy = scan_all_buffers(shutdown_busycount2, NULL); 330 if (nbusy) { 331 /* 332 * Failed to sync all blocks. Indicate this and don't 333 * unmount filesystems (thus forcing an fsck on reboot). 334 */ 335 kprintf("giving up on %d buffers\n", nbusy); 336 #ifdef DDB 337 Debugger("busy buffer problem"); 338 #endif /* DDB */ 339 tsleep(boot, 0, "shutdn", hz * 5 + 1); 340 } else { 341 kprintf("done\n"); 342 /* 343 * Unmount filesystems 344 */ 345 if (panicstr == NULL) 346 vfs_unmountall(); 347 } 348 tsleep(boot, 0, "shutdn", hz / 10 + 1); 349 } 350 351 print_uptime(); 352 353 /* 354 * Ok, now do things that assume all filesystem activity has 355 * been completed. 356 */ 357 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 358 crit_enter(); 359 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) 360 dumpsys(); 361 362 /* Now that we're going to really halt the system... */ 363 EVENTHANDLER_INVOKE(shutdown_final, howto); 364 365 for(;;) ; /* safety against shutdown_reset not working */ 366 /* NOTREACHED */ 367 } 368 369 static int 370 shutdown_busycount1(struct buf *bp, void *info) 371 { 372 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0) 373 return(1); 374 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) 375 return (1); 376 return (0); 377 } 378 379 static int 380 shutdown_busycount2(struct buf *bp, void *info) 381 { 382 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) || 383 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 384 /* 385 * Only count buffers undergoing write I/O 386 * on the related vnode. 387 */ 388 if (bp->b_vp == NULL || 389 bp->b_vp->v_track_write.bk_active == 0) { 390 return (0); 391 } 392 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 393 kprintf( 394 "%p dev:?, flags:%08x, loffset:%lld, doffset:%lld\n", 395 bp, 396 bp->b_flags, bp->b_loffset, 397 bp->b_bio2.bio_offset); 398 #endif 399 return(1); 400 } 401 return(0); 402 } 403 404 /* 405 * If the shutdown was a clean halt, behave accordingly. 406 */ 407 static void 408 shutdown_halt(void *junk, int howto) 409 { 410 if (howto & RB_HALT) { 411 kprintf("\n"); 412 kprintf("The operating system has halted.\n"); 413 kprintf("Please press any key to reboot.\n\n"); 414 switch (cngetc()) { 415 case -1: /* No console, just die */ 416 cpu_halt(); 417 /* NOTREACHED */ 418 default: 419 howto &= ~RB_HALT; 420 break; 421 } 422 } 423 } 424 425 /* 426 * Check to see if the system paniced, pause and then reboot 427 * according to the specified delay. 428 */ 429 static void 430 shutdown_panic(void *junk, int howto) 431 { 432 int loop; 433 434 if (howto & RB_DUMP) { 435 if (PANIC_REBOOT_WAIT_TIME != 0) { 436 if (PANIC_REBOOT_WAIT_TIME != -1) { 437 kprintf("Automatic reboot in %d seconds - " 438 "press a key on the console to abort\n", 439 PANIC_REBOOT_WAIT_TIME); 440 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 441 loop > 0; --loop) { 442 DELAY(1000 * 100); /* 1/10th second */ 443 /* Did user type a key? */ 444 if (cncheckc() != -1) 445 break; 446 } 447 if (!loop) 448 return; 449 } 450 } else { /* zero time specified - reboot NOW */ 451 return; 452 } 453 kprintf("--> Press a key on the console to reboot,\n"); 454 kprintf("--> or switch off the system now.\n"); 455 cngetc(); 456 } 457 } 458 459 /* 460 * Everything done, now reset 461 */ 462 static void 463 shutdown_reset(void *junk, int howto) 464 { 465 kprintf("Rebooting...\n"); 466 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */ 467 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 468 cpu_reset(); 469 /* NOTREACHED */ /* assuming reset worked */ 470 } 471 472 /* 473 * Try to remove FS references in the specified process. This function 474 * is used during shutdown 475 */ 476 static 477 void 478 shutdown_cleanup_proc(struct proc *p) 479 { 480 struct filedesc *fdp; 481 struct vmspace *vm; 482 483 if (p == NULL) 484 return; 485 if ((fdp = p->p_fd) != NULL) { 486 kern_closefrom(0); 487 if (fdp->fd_cdir) { 488 cache_drop(&fdp->fd_ncdir); 489 vrele(fdp->fd_cdir); 490 fdp->fd_cdir = NULL; 491 } 492 if (fdp->fd_rdir) { 493 cache_drop(&fdp->fd_nrdir); 494 vrele(fdp->fd_rdir); 495 fdp->fd_rdir = NULL; 496 } 497 if (fdp->fd_jdir) { 498 cache_drop(&fdp->fd_njdir); 499 vrele(fdp->fd_jdir); 500 fdp->fd_jdir = NULL; 501 } 502 } 503 if (p->p_vkernel) 504 vkernel_exit(p); 505 if (p->p_textvp) { 506 vrele(p->p_textvp); 507 p->p_textvp = NULL; 508 } 509 vm = p->p_vmspace; 510 if (vm != NULL) { 511 pmap_remove_pages(vmspace_pmap(vm), 512 VM_MIN_USER_ADDRESS, 513 VM_MAX_USER_ADDRESS); 514 vm_map_remove(&vm->vm_map, 515 VM_MIN_USER_ADDRESS, 516 VM_MAX_USER_ADDRESS); 517 } 518 } 519 520 /* 521 * Magic number for savecore 522 * 523 * exported (symorder) and used at least by savecore(8) 524 * 525 */ 526 static u_long const dumpmag = 0x8fca0101UL; 527 528 static int dumpsize = 0; /* also for savecore */ 529 530 static int dodump = 1; 531 532 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, 533 "Try to perform coredump on kernel panic"); 534 535 static int 536 setdumpdev(cdev_t dev) 537 { 538 int psize; 539 long newdumplo; 540 541 if (dev == NOCDEV) { 542 dumpdev = dev; 543 return (0); 544 } 545 psize = dev_dpsize(dev); 546 if (psize == -1) 547 return (ENXIO); 548 /* 549 * XXX should clean up checking in dumpsys() to be more like this. 550 */ 551 newdumplo = psize - Maxmem * (PAGE_SIZE / DEV_BSIZE); 552 if (newdumplo <= LABELSECTOR) 553 return (ENOSPC); 554 dumpdev = dev; 555 dumplo = newdumplo; 556 return (0); 557 } 558 559 560 /* ARGSUSED */ 561 static void dump_conf (void *dummy); 562 static void 563 dump_conf(void *dummy) 564 { 565 char *path; 566 cdev_t dev; 567 568 path = kmalloc(MNAMELEN, M_TEMP, M_WAITOK); 569 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) { 570 dev = kgetdiskbyname(path); 571 if (dev != NOCDEV) 572 dumpdev = dev; 573 } 574 kfree(path, M_TEMP); 575 if (setdumpdev(dumpdev) != 0) 576 dumpdev = NOCDEV; 577 } 578 579 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL) 580 581 static int 582 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS) 583 { 584 int error; 585 udev_t ndumpdev; 586 587 ndumpdev = dev2udev(dumpdev); 588 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req); 589 if (error == 0 && req->newptr != NULL) 590 error = setdumpdev(udev2dev(ndumpdev, 0)); 591 return (error); 592 } 593 594 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW, 595 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,udev_t", ""); 596 597 /* 598 * Doadump comes here after turning off memory management and 599 * getting on the dump stack, either when called above, or by 600 * the auto-restart code. 601 */ 602 static void 603 dumpsys(void) 604 { 605 int error; 606 607 savectx(&dumppcb); 608 dumpthread = curthread; 609 if (dumping++) { 610 kprintf("Dump already in progress, bailing...\n"); 611 return; 612 } 613 if (!dodump) 614 return; 615 if (dumpdev == NOCDEV) 616 return; 617 dumpsize = Maxmem; 618 kprintf("\ndumping to dev %s, offset %ld\n", devtoname(dumpdev), dumplo); 619 kprintf("dump "); 620 error = dev_ddump(dumpdev); 621 if (error == 0) { 622 kprintf("succeeded\n"); 623 return; 624 } 625 kprintf("failed, reason: "); 626 switch (error) { 627 case ENOSYS: 628 case ENODEV: 629 kprintf("device doesn't support a dump routine\n"); 630 break; 631 632 case ENXIO: 633 kprintf("device bad\n"); 634 break; 635 636 case EFAULT: 637 kprintf("device not ready\n"); 638 break; 639 640 case EINVAL: 641 kprintf("area improper\n"); 642 break; 643 644 case EIO: 645 kprintf("i/o error\n"); 646 break; 647 648 case EINTR: 649 kprintf("aborted from console\n"); 650 break; 651 652 default: 653 kprintf("unknown, error = %d\n", error); 654 break; 655 } 656 } 657 658 int 659 dumpstatus(vm_offset_t addr, off_t count) 660 { 661 int c; 662 663 if (addr % (1024 * 1024) == 0) { 664 #ifdef HW_WDOG 665 if (wdog_tickler) 666 (*wdog_tickler)(); 667 #endif 668 kprintf("%ld ", (long)(count / (1024 * 1024))); 669 } 670 671 if ((c = cncheckc()) == 0x03) 672 return -1; 673 else if (c != -1) 674 kprintf("[CTRL-C to abort] "); 675 676 return 0; 677 } 678 679 /* 680 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 681 * and then reboots. If we are called twice, then we avoid trying to sync 682 * the disks as this often leads to recursive panics. 683 */ 684 void 685 panic(const char *fmt, ...) 686 { 687 int bootopt, newpanic; 688 __va_list ap; 689 static char buf[256]; 690 691 #ifdef SMP 692 /* 693 * If a panic occurs on multiple cpus before the first is able to 694 * halt the other cpus, only one cpu is allowed to take the panic. 695 * Attempt to be verbose about this situation but if the kprintf() 696 * itself panics don't let us overrun the kernel stack. 697 * 698 * Be very nasty about descheduling our thread at the lowest 699 * level possible in an attempt to freeze the thread without 700 * inducing further panics. 701 * 702 * Bumping gd_trap_nesting_level will also bypass assertions in 703 * lwkt_switch() and allow us to switch away even if we are a 704 * FAST interrupt or IPI. 705 */ 706 if (atomic_poll_acquire_int(&panic_cpu_interlock)) { 707 panic_cpu_gd = mycpu; 708 } else if (panic_cpu_gd != mycpu) { 709 crit_enter(); 710 ++mycpu->gd_trap_nesting_level; 711 if (mycpu->gd_trap_nesting_level < 25) { 712 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n", 713 mycpu->gd_cpuid, curthread); 714 } 715 curthread->td_release = NULL; /* be a grinch */ 716 for (;;) { 717 lwkt_deschedule_self(curthread); 718 lwkt_switch(); 719 } 720 /* NOT REACHED */ 721 /* --mycpu->gd_trap_nesting_level */ 722 /* crit_exit() */ 723 } 724 #endif 725 bootopt = RB_AUTOBOOT | RB_DUMP; 726 if (sync_on_panic == 0) 727 bootopt |= RB_NOSYNC; 728 newpanic = 0; 729 if (panicstr) 730 bootopt |= RB_NOSYNC; 731 else { 732 panicstr = fmt; 733 newpanic = 1; 734 } 735 736 __va_start(ap, fmt); 737 kvsnprintf(buf, sizeof(buf), fmt, ap); 738 if (panicstr == fmt) 739 panicstr = buf; 740 __va_end(ap); 741 kprintf("panic: %s\n", buf); 742 #ifdef SMP 743 /* three separate prints in case of an unmapped page and trap */ 744 kprintf("mp_lock = %08x; ", mp_lock); 745 kprintf("cpuid = %d; ", mycpu->gd_cpuid); 746 kprintf("lapic.id = %08x\n", lapic.id); 747 #endif 748 749 #if defined(DDB) 750 if (newpanic && trace_on_panic) 751 db_print_backtrace(); 752 if (debugger_on_panic) 753 Debugger ("panic"); 754 #endif 755 boot(bootopt); 756 } 757 758 /* 759 * Support for poweroff delay. 760 */ 761 #ifndef POWEROFF_DELAY 762 # define POWEROFF_DELAY 5000 763 #endif 764 static int poweroff_delay = POWEROFF_DELAY; 765 766 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 767 &poweroff_delay, 0, ""); 768 769 static void 770 poweroff_wait(void *junk, int howto) 771 { 772 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0) 773 return; 774 DELAY(poweroff_delay * 1000); 775 } 776 777 /* 778 * Some system processes (e.g. syncer) need to be stopped at appropriate 779 * points in their main loops prior to a system shutdown, so that they 780 * won't interfere with the shutdown process (e.g. by holding a disk buf 781 * to cause sync to fail). For each of these system processes, register 782 * shutdown_kproc() as a handler for one of shutdown events. 783 */ 784 static int kproc_shutdown_wait = 60; 785 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 786 &kproc_shutdown_wait, 0, ""); 787 788 void 789 shutdown_kproc(void *arg, int howto) 790 { 791 struct thread *td; 792 struct proc *p; 793 int error; 794 795 if (panicstr) 796 return; 797 798 td = (struct thread *)arg; 799 if ((p = td->td_proc) != NULL) { 800 kprintf("Waiting (max %d seconds) for system process `%s' to stop...", 801 kproc_shutdown_wait, p->p_comm); 802 } else { 803 kprintf("Waiting (max %d seconds) for system thread %s to stop...", 804 kproc_shutdown_wait, td->td_comm); 805 } 806 error = suspend_kproc(td, kproc_shutdown_wait * hz); 807 808 if (error == EWOULDBLOCK) 809 kprintf("timed out\n"); 810 else 811 kprintf("stopped\n"); 812 } 813