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 1.62 2008/01/05 13:23:48 corecode 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/priv.h> 57 #include <sys/fcntl.h> /* FREAD */ 58 #include <sys/stat.h> /* S_IFCHR */ 59 #include <sys/vnode.h> 60 #include <sys/kernel.h> 61 #include <sys/kthread.h> 62 #include <sys/malloc.h> 63 #include <sys/mount.h> 64 #include <sys/queue.h> 65 #include <sys/sysctl.h> 66 #include <sys/vkernel.h> 67 #include <sys/conf.h> 68 #include <sys/sysproto.h> 69 #include <sys/device.h> 70 #include <sys/cons.h> 71 #include <sys/shm.h> 72 #include <sys/kern_syscall.h> 73 #include <vm/vm_map.h> 74 #include <vm/pmap.h> 75 76 #include <sys/thread2.h> 77 #include <sys/buf2.h> 78 79 #include <machine/pcb.h> 80 #include <machine/clock.h> 81 #include <machine/md_var.h> 82 #include <machine/smp.h> /* smp_active_mask, cpuid */ 83 #include <machine/vmparam.h> 84 85 #include <sys/signalvar.h> 86 87 #ifndef PANIC_REBOOT_WAIT_TIME 88 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */ 89 #endif 90 91 /* 92 * Note that stdarg.h and the ANSI style va_start macro is used for both 93 * ANSI and traditional C compilers. We use the machine version to stay 94 * within the confines of the kernel header files. 95 */ 96 #include <machine/stdarg.h> 97 98 #ifdef DDB 99 #include <ddb/ddb.h> 100 #ifdef DDB_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, CTLFLAG_RW, 106 &debugger_on_panic, 0, "Run debugger on kernel panic"); 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 SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW, 148 &bootverbose, 0, "Verbose kernel messages"); 149 150 int cold = 1; /* note: assignment to force non-bss */ 151 int dumplo; /* OBSOLETE - savecore compat */ 152 u_int64_t dumplo64; 153 154 static void boot (int) __dead2; 155 static void dumpsys (void); 156 static int setdumpdev (cdev_t dev); 157 static void poweroff_wait (void *, int); 158 static void print_uptime (void); 159 static void shutdown_halt (void *junk, int howto); 160 static void shutdown_panic (void *junk, int howto); 161 static void shutdown_reset (void *junk, int howto); 162 static int shutdown_busycount1(struct buf *bp, void *info); 163 static int shutdown_busycount2(struct buf *bp, void *info); 164 static void shutdown_cleanup_proc(struct proc *p); 165 166 /* register various local shutdown events */ 167 static void 168 shutdown_conf(void *unused) 169 { 170 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST); 171 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100); 172 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100); 173 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200); 174 } 175 176 SYSINIT(shutdown_conf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, shutdown_conf, NULL) 177 178 /* ARGSUSED */ 179 180 /* 181 * The system call that results in a reboot 182 */ 183 int 184 sys_reboot(struct reboot_args *uap) 185 { 186 struct thread *td = curthread; 187 int error; 188 189 if ((error = priv_check(td, PRIV_REBOOT))) 190 return (error); 191 192 boot(uap->opt); 193 return (0); 194 } 195 196 /* 197 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 198 */ 199 static int shutdown_howto = 0; 200 201 void 202 shutdown_nice(int howto) 203 { 204 shutdown_howto = howto; 205 206 /* Send a signal to init(8) and have it shutdown the world */ 207 if (initproc != NULL) { 208 ksignal(initproc, SIGINT); 209 } else { 210 /* No init(8) running, so simply reboot */ 211 boot(RB_NOSYNC); 212 } 213 return; 214 } 215 static int waittime = -1; 216 static struct thread *dumpthread; 217 static struct pcb dumppcb; 218 219 static void 220 print_uptime(void) 221 { 222 int f; 223 struct timespec ts; 224 225 getnanouptime(&ts); 226 kprintf("Uptime: "); 227 f = 0; 228 if (ts.tv_sec >= 86400) { 229 kprintf("%ldd", ts.tv_sec / 86400); 230 ts.tv_sec %= 86400; 231 f = 1; 232 } 233 if (f || ts.tv_sec >= 3600) { 234 kprintf("%ldh", ts.tv_sec / 3600); 235 ts.tv_sec %= 3600; 236 f = 1; 237 } 238 if (f || ts.tv_sec >= 60) { 239 kprintf("%ldm", ts.tv_sec / 60); 240 ts.tv_sec %= 60; 241 f = 1; 242 } 243 kprintf("%lds\n", ts.tv_sec); 244 } 245 246 /* 247 * Go through the rigmarole of shutting down.. 248 * this used to be in machdep.c but I'll be dammned if I could see 249 * anything machine dependant in it. 250 */ 251 static void 252 boot(int howto) 253 { 254 /* 255 * Get rid of any user scheduler baggage and then give 256 * us a high priority. 257 */ 258 if (curthread->td_release) 259 curthread->td_release(curthread); 260 lwkt_setpri_self(TDPRI_MAX); 261 262 /* collect extra flags that shutdown_nice might have set */ 263 howto |= shutdown_howto; 264 265 #ifdef SMP 266 /* 267 * We really want to shutdown on the BSP. Subsystems such as ACPI 268 * can't power-down the box otherwise. 269 */ 270 if (smp_active_mask > 1) { 271 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid); 272 } 273 if (panicstr == NULL && mycpu->gd_cpuid != 0) { 274 kprintf("Switching to cpu #0 for shutdown\n"); 275 lwkt_setcpu_self(globaldata_find(0)); 276 } 277 #endif 278 /* 279 * Do any callouts that should be done BEFORE syncing the filesystems. 280 */ 281 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 282 283 /* 284 * Try to get rid of any remaining FS references. The calling 285 * process, proc0, and init may still hold references. The 286 * VFS cache subsystem may still hold a root reference to root. 287 * 288 * XXX this needs work. We really need to SIGSTOP all remaining 289 * processes in order to avoid blowups due to proc0's filesystem 290 * references going away. For now just make sure that the init 291 * process is stopped. 292 */ 293 if (panicstr == NULL) { 294 shutdown_cleanup_proc(curproc); 295 shutdown_cleanup_proc(&proc0); 296 if (initproc) { 297 if (initproc != curproc) { 298 ksignal(initproc, SIGSTOP); 299 tsleep(boot, 0, "shutdn", hz / 20); 300 } 301 shutdown_cleanup_proc(initproc); 302 } 303 vfs_cache_setroot(NULL, NULL); 304 } 305 306 /* 307 * Now sync filesystems 308 */ 309 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 310 int iter, nbusy, pbusy; 311 312 waittime = 0; 313 kprintf("\nsyncing disks... "); 314 315 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 316 317 /* 318 * With soft updates, some buffers that are 319 * written will be remarked as dirty until other 320 * buffers are written. 321 */ 322 for (iter = pbusy = 0; iter < 20; iter++) { 323 nbusy = scan_all_buffers(shutdown_busycount1, NULL); 324 if (nbusy == 0) 325 break; 326 kprintf("%d ", nbusy); 327 if (nbusy < pbusy) 328 iter = 0; 329 pbusy = nbusy; 330 /* 331 * XXX: 332 * Process soft update work queue if buffers don't sync 333 * after 6 iterations by permitting the syncer to run. 334 */ 335 if (iter > 5) 336 bio_ops_sync(NULL); 337 338 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 339 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1); 340 } 341 kprintf("\n"); 342 /* 343 * Count only busy local buffers to prevent forcing 344 * a fsck if we're just a client of a wedged NFS server 345 */ 346 nbusy = scan_all_buffers(shutdown_busycount2, NULL); 347 if (nbusy) { 348 /* 349 * Failed to sync all blocks. Indicate this and don't 350 * unmount filesystems (thus forcing an fsck on reboot). 351 */ 352 kprintf("giving up on %d buffers\n", nbusy); 353 #ifdef DDB 354 Debugger("busy buffer problem"); 355 #endif /* DDB */ 356 tsleep(boot, 0, "shutdn", hz * 5 + 1); 357 } else { 358 kprintf("done\n"); 359 /* 360 * Unmount filesystems 361 */ 362 if (panicstr == NULL) 363 vfs_unmountall(); 364 } 365 tsleep(boot, 0, "shutdn", hz / 10 + 1); 366 } 367 368 print_uptime(); 369 370 /* 371 * Dump before doing post_sync shutdown ops 372 */ 373 crit_enter(); 374 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) 375 dumpsys(); 376 377 /* 378 * Ok, now do things that assume all filesystem activity has 379 * been completed. This will also call the device shutdown 380 * methods. 381 */ 382 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 383 384 /* Now that we're going to really halt the system... */ 385 EVENTHANDLER_INVOKE(shutdown_final, howto); 386 387 for(;;) ; /* safety against shutdown_reset not working */ 388 /* NOTREACHED */ 389 } 390 391 static int 392 shutdown_busycount1(struct buf *bp, void *info) 393 { 394 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0) 395 return(1); 396 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) 397 return (1); 398 return (0); 399 } 400 401 static int 402 shutdown_busycount2(struct buf *bp, void *info) 403 { 404 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) || 405 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 406 /* 407 * Only count buffers undergoing write I/O 408 * on the related vnode. 409 */ 410 if (bp->b_vp == NULL || 411 bio_track_active(&bp->b_vp->v_track_write) == 0) { 412 return (0); 413 } 414 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 415 kprintf( 416 "%p dev:?, flags:%08x, loffset:%lld, doffset:%lld\n", 417 bp, 418 bp->b_flags, bp->b_loffset, 419 bp->b_bio2.bio_offset); 420 #endif 421 return(1); 422 } 423 return(0); 424 } 425 426 /* 427 * If the shutdown was a clean halt, behave accordingly. 428 */ 429 static void 430 shutdown_halt(void *junk, int howto) 431 { 432 if (howto & RB_HALT) { 433 kprintf("\n"); 434 kprintf("The operating system has halted.\n"); 435 #ifdef _KERNEL_VIRTUAL 436 cpu_halt(); 437 #else 438 kprintf("Please press any key to reboot.\n\n"); 439 switch (cngetc()) { 440 case -1: /* No console, just die */ 441 cpu_halt(); 442 /* NOTREACHED */ 443 default: 444 howto &= ~RB_HALT; 445 break; 446 } 447 #endif 448 } 449 } 450 451 /* 452 * Check to see if the system paniced, pause and then reboot 453 * according to the specified delay. 454 */ 455 static void 456 shutdown_panic(void *junk, int howto) 457 { 458 int loop; 459 460 if (howto & RB_DUMP) { 461 if (PANIC_REBOOT_WAIT_TIME != 0) { 462 if (PANIC_REBOOT_WAIT_TIME != -1) { 463 kprintf("Automatic reboot in %d seconds - " 464 "press a key on the console to abort\n", 465 PANIC_REBOOT_WAIT_TIME); 466 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 467 loop > 0; --loop) { 468 DELAY(1000 * 100); /* 1/10th second */ 469 /* Did user type a key? */ 470 if (cncheckc() != -1) 471 break; 472 } 473 if (!loop) 474 return; 475 } 476 } else { /* zero time specified - reboot NOW */ 477 return; 478 } 479 kprintf("--> Press a key on the console to reboot,\n"); 480 kprintf("--> or switch off the system now.\n"); 481 cngetc(); 482 } 483 } 484 485 /* 486 * Everything done, now reset 487 */ 488 static void 489 shutdown_reset(void *junk, int howto) 490 { 491 kprintf("Rebooting...\n"); 492 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */ 493 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 494 cpu_reset(); 495 /* NOTREACHED */ /* assuming reset worked */ 496 } 497 498 /* 499 * Try to remove FS references in the specified process. This function 500 * is used during shutdown 501 */ 502 static 503 void 504 shutdown_cleanup_proc(struct proc *p) 505 { 506 struct filedesc *fdp; 507 struct vmspace *vm; 508 509 if (p == NULL) 510 return; 511 if ((fdp = p->p_fd) != NULL) { 512 kern_closefrom(0); 513 if (fdp->fd_cdir) { 514 cache_drop(&fdp->fd_ncdir); 515 vrele(fdp->fd_cdir); 516 fdp->fd_cdir = NULL; 517 } 518 if (fdp->fd_rdir) { 519 cache_drop(&fdp->fd_nrdir); 520 vrele(fdp->fd_rdir); 521 fdp->fd_rdir = NULL; 522 } 523 if (fdp->fd_jdir) { 524 cache_drop(&fdp->fd_njdir); 525 vrele(fdp->fd_jdir); 526 fdp->fd_jdir = NULL; 527 } 528 } 529 if (p->p_vkernel) 530 vkernel_exit(p); 531 if (p->p_textvp) { 532 vrele(p->p_textvp); 533 p->p_textvp = NULL; 534 } 535 vm = p->p_vmspace; 536 if (vm != NULL) { 537 pmap_remove_pages(vmspace_pmap(vm), 538 VM_MIN_USER_ADDRESS, 539 VM_MAX_USER_ADDRESS); 540 vm_map_remove(&vm->vm_map, 541 VM_MIN_USER_ADDRESS, 542 VM_MAX_USER_ADDRESS); 543 } 544 } 545 546 /* 547 * Magic number for savecore 548 * 549 * exported (symorder) and used at least by savecore(8) 550 * 551 * Mark it as used so that gcc doesn't optimize it away. 552 */ 553 __attribute__((__used__)) 554 static u_long const dumpmag = 0x8fca0101UL; 555 556 static int dumpsize = 0; /* also for savecore */ 557 558 static int dodump = 1; 559 560 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, 561 "Try to perform coredump on kernel panic"); 562 563 static int 564 setdumpdev(cdev_t dev) 565 { 566 struct partinfo pinfo; 567 u_int64_t newdumplo; 568 int error; 569 int doopen; 570 571 if (dev == NULL) { 572 dumpdev = dev; 573 return (0); 574 } 575 bzero(&pinfo, sizeof(pinfo)); 576 577 /* 578 * We have to open the device before we can perform ioctls on it, 579 * or the slice/label data may not be present. Device opens are 580 * usually tracked by specfs, but the dump device can be set in 581 * early boot and may not be open so this is somewhat of a hack. 582 */ 583 doopen = (dev->si_sysref.refcnt == 1); 584 if (doopen) { 585 error = dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred); 586 if (error) 587 return (error); 588 } 589 error = dev_dioctl(dev, DIOCGPART, (void *)&pinfo, 0, 590 proc0.p_ucred, NULL); 591 if (doopen) 592 dev_dclose(dev, FREAD, S_IFCHR); 593 if (error || pinfo.media_blocks == 0 || pinfo.media_blksize == 0) 594 return (ENXIO); 595 596 newdumplo = pinfo.media_blocks - 597 ((u_int64_t)Maxmem * PAGE_SIZE / DEV_BSIZE); 598 if ((int64_t)newdumplo < (int64_t)pinfo.reserved_blocks) 599 return (ENOSPC); 600 dumpdev = dev; 601 dumplo64 = newdumplo; 602 return (0); 603 } 604 605 606 /* ARGSUSED */ 607 static void dump_conf (void *dummy); 608 static void 609 dump_conf(void *dummy) 610 { 611 char *path; 612 cdev_t dev; 613 614 path = kmalloc(MNAMELEN, M_TEMP, M_WAITOK); 615 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) { 616 dev = kgetdiskbyname(path); 617 if (dev != NULL) 618 dumpdev = dev; 619 } 620 kfree(path, M_TEMP); 621 if (setdumpdev(dumpdev) != 0) 622 dumpdev = NULL; 623 } 624 625 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL) 626 627 static int 628 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS) 629 { 630 int error; 631 udev_t ndumpdev; 632 633 ndumpdev = dev2udev(dumpdev); 634 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req); 635 if (error == 0 && req->newptr != NULL) 636 error = setdumpdev(udev2dev(ndumpdev, 0)); 637 return (error); 638 } 639 640 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW, 641 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,udev_t", ""); 642 643 /* 644 * Doadump comes here after turning off memory management and 645 * getting on the dump stack, either when called above, or by 646 * the auto-restart code. 647 */ 648 static void 649 dumpsys(void) 650 { 651 int error; 652 653 savectx(&dumppcb); 654 dumpthread = curthread; 655 if (dumping++) { 656 kprintf("Dump already in progress, bailing...\n"); 657 return; 658 } 659 if (!dodump) 660 return; 661 if (dumpdev == NULL) 662 return; 663 dumpsize = Maxmem; 664 kprintf("\ndumping to dev %s, blockno %lld\n", 665 devtoname(dumpdev), 666 (long long)dumplo64); 667 kprintf("dump "); 668 error = dev_ddump(dumpdev); 669 if (error == 0) { 670 kprintf("succeeded\n"); 671 return; 672 } 673 kprintf("failed, reason: "); 674 switch (error) { 675 case ENOSYS: 676 case ENODEV: 677 kprintf("device doesn't support a dump routine\n"); 678 break; 679 680 case ENXIO: 681 kprintf("device bad\n"); 682 break; 683 684 case EFAULT: 685 kprintf("device not ready\n"); 686 break; 687 688 case EINVAL: 689 kprintf("area improper\n"); 690 break; 691 692 case EIO: 693 kprintf("i/o error\n"); 694 break; 695 696 case EINTR: 697 kprintf("aborted from console\n"); 698 break; 699 700 default: 701 kprintf("unknown, error = %d\n", error); 702 break; 703 } 704 } 705 706 int 707 dumpstatus(vm_offset_t addr, off_t count) 708 { 709 int c; 710 711 if (addr % (1024 * 1024) == 0) { 712 #ifdef HW_WDOG 713 if (wdog_tickler) 714 (*wdog_tickler)(); 715 #endif 716 kprintf("%ld ", (long)(count / (1024 * 1024))); 717 } 718 719 if ((c = cncheckc()) == 0x03) 720 return -1; 721 else if (c != -1) 722 kprintf("[CTRL-C to abort] "); 723 724 return 0; 725 } 726 727 /* 728 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 729 * and then reboots. If we are called twice, then we avoid trying to sync 730 * the disks as this often leads to recursive panics. 731 */ 732 void 733 panic(const char *fmt, ...) 734 { 735 int bootopt, newpanic; 736 __va_list ap; 737 static char buf[256]; 738 739 #ifdef SMP 740 /* 741 * If a panic occurs on multiple cpus before the first is able to 742 * halt the other cpus, only one cpu is allowed to take the panic. 743 * Attempt to be verbose about this situation but if the kprintf() 744 * itself panics don't let us overrun the kernel stack. 745 * 746 * Be very nasty about descheduling our thread at the lowest 747 * level possible in an attempt to freeze the thread without 748 * inducing further panics. 749 * 750 * Bumping gd_trap_nesting_level will also bypass assertions in 751 * lwkt_switch() and allow us to switch away even if we are a 752 * FAST interrupt or IPI. 753 */ 754 if (atomic_poll_acquire_int(&panic_cpu_interlock)) { 755 panic_cpu_gd = mycpu; 756 } else if (panic_cpu_gd != mycpu) { 757 crit_enter(); 758 ++mycpu->gd_trap_nesting_level; 759 if (mycpu->gd_trap_nesting_level < 25) { 760 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n", 761 mycpu->gd_cpuid, curthread); 762 } 763 curthread->td_release = NULL; /* be a grinch */ 764 for (;;) { 765 lwkt_deschedule_self(curthread); 766 lwkt_switch(); 767 } 768 /* NOT REACHED */ 769 /* --mycpu->gd_trap_nesting_level */ 770 /* crit_exit() */ 771 } 772 #endif 773 bootopt = RB_AUTOBOOT | RB_DUMP; 774 if (sync_on_panic == 0) 775 bootopt |= RB_NOSYNC; 776 newpanic = 0; 777 if (panicstr) 778 bootopt |= RB_NOSYNC; 779 else { 780 panicstr = fmt; 781 newpanic = 1; 782 } 783 784 __va_start(ap, fmt); 785 kvsnprintf(buf, sizeof(buf), fmt, ap); 786 if (panicstr == fmt) 787 panicstr = buf; 788 __va_end(ap); 789 kprintf("panic: %s\n", buf); 790 #ifdef SMP 791 /* two separate prints in case of an unmapped page and trap */ 792 kprintf("mp_lock = %08x; ", mp_lock); 793 kprintf("cpuid = %d\n", mycpu->gd_cpuid); 794 #endif 795 796 #if defined(DDB) 797 if (newpanic && trace_on_panic) 798 print_backtrace(); 799 if (debugger_on_panic) 800 Debugger("panic"); 801 #endif 802 boot(bootopt); 803 } 804 805 /* 806 * Support for poweroff delay. 807 */ 808 #ifndef POWEROFF_DELAY 809 # define POWEROFF_DELAY 5000 810 #endif 811 static int poweroff_delay = POWEROFF_DELAY; 812 813 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 814 &poweroff_delay, 0, ""); 815 816 static void 817 poweroff_wait(void *junk, int howto) 818 { 819 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0) 820 return; 821 DELAY(poweroff_delay * 1000); 822 } 823 824 /* 825 * Some system processes (e.g. syncer) need to be stopped at appropriate 826 * points in their main loops prior to a system shutdown, so that they 827 * won't interfere with the shutdown process (e.g. by holding a disk buf 828 * to cause sync to fail). For each of these system processes, register 829 * shutdown_kproc() as a handler for one of shutdown events. 830 */ 831 static int kproc_shutdown_wait = 60; 832 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 833 &kproc_shutdown_wait, 0, ""); 834 835 void 836 shutdown_kproc(void *arg, int howto) 837 { 838 struct thread *td; 839 struct proc *p; 840 int error; 841 842 if (panicstr) 843 return; 844 845 td = (struct thread *)arg; 846 if ((p = td->td_proc) != NULL) { 847 kprintf("Waiting (max %d seconds) for system process `%s' to stop...", 848 kproc_shutdown_wait, p->p_comm); 849 } else { 850 kprintf("Waiting (max %d seconds) for system thread %s to stop...", 851 kproc_shutdown_wait, td->td_comm); 852 } 853 error = suspend_kproc(td, kproc_shutdown_wait * hz); 854 855 if (error == EWOULDBLOCK) 856 kprintf("timed out\n"); 857 else 858 kprintf("stopped\n"); 859 } 860