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 #ifdef DDB_UNATTENDED 100 int debugger_on_panic = 0; 101 #else 102 int debugger_on_panic = 1; 103 #endif 104 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW, 105 &debugger_on_panic, 0, "Run debugger on kernel panic"); 106 107 extern void db_print_backtrace(void); 108 109 #ifdef DDB_TRACE 110 int trace_on_panic = 1; 111 #else 112 int trace_on_panic = 0; 113 #endif 114 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW, 115 &trace_on_panic, 0, "Print stack trace on kernel panic"); 116 #endif 117 118 static int sync_on_panic = 1; 119 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW, 120 &sync_on_panic, 0, "Do a sync before rebooting from a panic"); 121 122 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment"); 123 124 #ifdef HW_WDOG 125 /* 126 * If there is a hardware watchdog, point this at the function needed to 127 * hold it off. 128 * It's needed when the kernel needs to do some lengthy operations. 129 * e.g. in wd.c when dumping core.. It's most annoying to have 130 * your precious core-dump only half written because the wdog kicked in. 131 */ 132 watchdog_tickle_fn wdog_tickler = NULL; 133 #endif /* HW_WDOG */ 134 135 /* 136 * Variable panicstr contains argument to first call to panic; used as flag 137 * to indicate that the kernel has already called panic. 138 */ 139 const char *panicstr; 140 141 int dumping; /* system is dumping */ 142 #ifdef SMP 143 u_int panic_cpu_interlock; /* panic interlock */ 144 globaldata_t panic_cpu_gd; /* which cpu took the panic */ 145 #endif 146 147 int bootverbose = 0; /* note: assignment to force non-bss */ 148 SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW, 149 &bootverbose, 0, "Verbose kernel messages"); 150 151 int cold = 1; /* note: assignment to force non-bss */ 152 int dumplo; /* OBSOLETE - savecore compat */ 153 u_int64_t dumplo64; 154 155 static void boot (int) __dead2; 156 static void dumpsys (void); 157 static int setdumpdev (cdev_t dev); 158 static void poweroff_wait (void *, int); 159 static void print_uptime (void); 160 static void shutdown_halt (void *junk, int howto); 161 static void shutdown_panic (void *junk, int howto); 162 static void shutdown_reset (void *junk, int howto); 163 static int shutdown_busycount1(struct buf *bp, void *info); 164 static int shutdown_busycount2(struct buf *bp, void *info); 165 static void shutdown_cleanup_proc(struct proc *p); 166 167 /* register various local shutdown events */ 168 static void 169 shutdown_conf(void *unused) 170 { 171 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST); 172 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100); 173 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100); 174 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200); 175 } 176 177 SYSINIT(shutdown_conf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, shutdown_conf, NULL) 178 179 /* ARGSUSED */ 180 181 /* 182 * The system call that results in a reboot 183 */ 184 int 185 sys_reboot(struct reboot_args *uap) 186 { 187 struct thread *td = curthread; 188 int error; 189 190 if ((error = priv_check(td, PRIV_ROOT))) 191 return (error); 192 193 boot(uap->opt); 194 return (0); 195 } 196 197 /* 198 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC 199 */ 200 static int shutdown_howto = 0; 201 202 void 203 shutdown_nice(int howto) 204 { 205 shutdown_howto = howto; 206 207 /* Send a signal to init(8) and have it shutdown the world */ 208 if (initproc != NULL) { 209 ksignal(initproc, SIGINT); 210 } else { 211 /* No init(8) running, so simply reboot */ 212 boot(RB_NOSYNC); 213 } 214 return; 215 } 216 static int waittime = -1; 217 static struct thread *dumpthread; 218 static struct pcb dumppcb; 219 220 static void 221 print_uptime(void) 222 { 223 int f; 224 struct timespec ts; 225 226 getnanouptime(&ts); 227 kprintf("Uptime: "); 228 f = 0; 229 if (ts.tv_sec >= 86400) { 230 kprintf("%ldd", ts.tv_sec / 86400); 231 ts.tv_sec %= 86400; 232 f = 1; 233 } 234 if (f || ts.tv_sec >= 3600) { 235 kprintf("%ldh", ts.tv_sec / 3600); 236 ts.tv_sec %= 3600; 237 f = 1; 238 } 239 if (f || ts.tv_sec >= 60) { 240 kprintf("%ldm", ts.tv_sec / 60); 241 ts.tv_sec %= 60; 242 f = 1; 243 } 244 kprintf("%lds\n", ts.tv_sec); 245 } 246 247 /* 248 * Go through the rigmarole of shutting down.. 249 * this used to be in machdep.c but I'll be dammned if I could see 250 * anything machine dependant in it. 251 */ 252 static void 253 boot(int howto) 254 { 255 /* 256 * Get rid of any user scheduler baggage and then give 257 * us a high priority. 258 */ 259 if (curthread->td_release) 260 curthread->td_release(curthread); 261 lwkt_setpri_self(TDPRI_MAX); 262 263 /* collect extra flags that shutdown_nice might have set */ 264 howto |= shutdown_howto; 265 266 #ifdef SMP 267 /* 268 * We really want to shutdown on the BSP. Subsystems such as ACPI 269 * can't power-down the box otherwise. 270 */ 271 if (smp_active_mask > 1) { 272 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid); 273 } 274 if (panicstr == NULL && mycpu->gd_cpuid != 0) { 275 kprintf("Switching to cpu #0 for shutdown\n"); 276 lwkt_setcpu_self(globaldata_find(0)); 277 } 278 #endif 279 /* 280 * Do any callouts that should be done BEFORE syncing the filesystems. 281 */ 282 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto); 283 284 /* 285 * Try to get rid of any remaining FS references. The calling 286 * process, proc0, and init may still hold references. The 287 * VFS cache subsystem may still hold a root reference to root. 288 * 289 * XXX this needs work. We really need to SIGSTOP all remaining 290 * processes in order to avoid blowups due to proc0's filesystem 291 * references going away. For now just make sure that the init 292 * process is stopped. 293 */ 294 if (panicstr == NULL) { 295 shutdown_cleanup_proc(curproc); 296 shutdown_cleanup_proc(&proc0); 297 if (initproc) { 298 if (initproc != curproc) { 299 ksignal(initproc, SIGSTOP); 300 tsleep(boot, 0, "shutdn", hz / 20); 301 } 302 shutdown_cleanup_proc(initproc); 303 } 304 vfs_cache_setroot(NULL, NULL); 305 } 306 307 /* 308 * Now sync filesystems 309 */ 310 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) { 311 int iter, nbusy, pbusy; 312 313 waittime = 0; 314 kprintf("\nsyncing disks... "); 315 316 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 317 318 /* 319 * With soft updates, some buffers that are 320 * written will be remarked as dirty until other 321 * buffers are written. 322 */ 323 for (iter = pbusy = 0; iter < 20; iter++) { 324 nbusy = scan_all_buffers(shutdown_busycount1, NULL); 325 if (nbusy == 0) 326 break; 327 kprintf("%d ", nbusy); 328 if (nbusy < pbusy) 329 iter = 0; 330 pbusy = nbusy; 331 /* 332 * XXX: 333 * Process soft update work queue if buffers don't sync 334 * after 6 iterations by permitting the syncer to run. 335 */ 336 if (iter > 5) 337 bio_ops_sync(NULL); 338 339 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */ 340 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1); 341 } 342 kprintf("\n"); 343 /* 344 * Count only busy local buffers to prevent forcing 345 * a fsck if we're just a client of a wedged NFS server 346 */ 347 nbusy = scan_all_buffers(shutdown_busycount2, NULL); 348 if (nbusy) { 349 /* 350 * Failed to sync all blocks. Indicate this and don't 351 * unmount filesystems (thus forcing an fsck on reboot). 352 */ 353 kprintf("giving up on %d buffers\n", nbusy); 354 #ifdef DDB 355 Debugger("busy buffer problem"); 356 #endif /* DDB */ 357 tsleep(boot, 0, "shutdn", hz * 5 + 1); 358 } else { 359 kprintf("done\n"); 360 /* 361 * Unmount filesystems 362 */ 363 if (panicstr == NULL) 364 vfs_unmountall(); 365 } 366 tsleep(boot, 0, "shutdn", hz / 10 + 1); 367 } 368 369 print_uptime(); 370 371 /* 372 * Dump before doing post_sync shutdown ops 373 */ 374 crit_enter(); 375 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) 376 dumpsys(); 377 378 /* 379 * Ok, now do things that assume all filesystem activity has 380 * been completed. This will also call the device shutdown 381 * methods. 382 */ 383 EVENTHANDLER_INVOKE(shutdown_post_sync, howto); 384 385 /* Now that we're going to really halt the system... */ 386 EVENTHANDLER_INVOKE(shutdown_final, howto); 387 388 for(;;) ; /* safety against shutdown_reset not working */ 389 /* NOTREACHED */ 390 } 391 392 static int 393 shutdown_busycount1(struct buf *bp, void *info) 394 { 395 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0) 396 return(1); 397 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) 398 return (1); 399 return (0); 400 } 401 402 static int 403 shutdown_busycount2(struct buf *bp, void *info) 404 { 405 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) || 406 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) { 407 /* 408 * Only count buffers undergoing write I/O 409 * on the related vnode. 410 */ 411 if (bp->b_vp == NULL || 412 bp->b_vp->v_track_write.bk_active == 0) { 413 return (0); 414 } 415 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC) 416 kprintf( 417 "%p dev:?, flags:%08x, loffset:%lld, doffset:%lld\n", 418 bp, 419 bp->b_flags, bp->b_loffset, 420 bp->b_bio2.bio_offset); 421 #endif 422 return(1); 423 } 424 return(0); 425 } 426 427 /* 428 * If the shutdown was a clean halt, behave accordingly. 429 */ 430 static void 431 shutdown_halt(void *junk, int howto) 432 { 433 if (howto & RB_HALT) { 434 kprintf("\n"); 435 kprintf("The operating system has halted.\n"); 436 #ifdef _KERNEL_VIRTUAL 437 cpu_halt(); 438 #else 439 kprintf("Please press any key to reboot.\n\n"); 440 switch (cngetc()) { 441 case -1: /* No console, just die */ 442 cpu_halt(); 443 /* NOTREACHED */ 444 default: 445 howto &= ~RB_HALT; 446 break; 447 } 448 #endif 449 } 450 } 451 452 /* 453 * Check to see if the system paniced, pause and then reboot 454 * according to the specified delay. 455 */ 456 static void 457 shutdown_panic(void *junk, int howto) 458 { 459 int loop; 460 461 if (howto & RB_DUMP) { 462 if (PANIC_REBOOT_WAIT_TIME != 0) { 463 if (PANIC_REBOOT_WAIT_TIME != -1) { 464 kprintf("Automatic reboot in %d seconds - " 465 "press a key on the console to abort\n", 466 PANIC_REBOOT_WAIT_TIME); 467 for (loop = PANIC_REBOOT_WAIT_TIME * 10; 468 loop > 0; --loop) { 469 DELAY(1000 * 100); /* 1/10th second */ 470 /* Did user type a key? */ 471 if (cncheckc() != -1) 472 break; 473 } 474 if (!loop) 475 return; 476 } 477 } else { /* zero time specified - reboot NOW */ 478 return; 479 } 480 kprintf("--> Press a key on the console to reboot,\n"); 481 kprintf("--> or switch off the system now.\n"); 482 cngetc(); 483 } 484 } 485 486 /* 487 * Everything done, now reset 488 */ 489 static void 490 shutdown_reset(void *junk, int howto) 491 { 492 kprintf("Rebooting...\n"); 493 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */ 494 /* cpu_boot(howto); */ /* doesn't do anything at the moment */ 495 cpu_reset(); 496 /* NOTREACHED */ /* assuming reset worked */ 497 } 498 499 /* 500 * Try to remove FS references in the specified process. This function 501 * is used during shutdown 502 */ 503 static 504 void 505 shutdown_cleanup_proc(struct proc *p) 506 { 507 struct filedesc *fdp; 508 struct vmspace *vm; 509 510 if (p == NULL) 511 return; 512 if ((fdp = p->p_fd) != NULL) { 513 kern_closefrom(0); 514 if (fdp->fd_cdir) { 515 cache_drop(&fdp->fd_ncdir); 516 vrele(fdp->fd_cdir); 517 fdp->fd_cdir = NULL; 518 } 519 if (fdp->fd_rdir) { 520 cache_drop(&fdp->fd_nrdir); 521 vrele(fdp->fd_rdir); 522 fdp->fd_rdir = NULL; 523 } 524 if (fdp->fd_jdir) { 525 cache_drop(&fdp->fd_njdir); 526 vrele(fdp->fd_jdir); 527 fdp->fd_jdir = NULL; 528 } 529 } 530 if (p->p_vkernel) 531 vkernel_exit(p); 532 if (p->p_textvp) { 533 vrele(p->p_textvp); 534 p->p_textvp = NULL; 535 } 536 vm = p->p_vmspace; 537 if (vm != NULL) { 538 pmap_remove_pages(vmspace_pmap(vm), 539 VM_MIN_USER_ADDRESS, 540 VM_MAX_USER_ADDRESS); 541 vm_map_remove(&vm->vm_map, 542 VM_MIN_USER_ADDRESS, 543 VM_MAX_USER_ADDRESS); 544 } 545 } 546 547 /* 548 * Magic number for savecore 549 * 550 * exported (symorder) and used at least by savecore(8) 551 * 552 * Mark it as used so that gcc doesn't optimize it away. 553 */ 554 __attribute__((__used__)) 555 static u_long const dumpmag = 0x8fca0101UL; 556 557 static int dumpsize = 0; /* also for savecore */ 558 559 static int dodump = 1; 560 561 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0, 562 "Try to perform coredump on kernel panic"); 563 564 static int 565 setdumpdev(cdev_t dev) 566 { 567 struct partinfo pinfo; 568 u_int64_t newdumplo; 569 int error; 570 int doopen; 571 572 if (dev == NULL) { 573 dumpdev = dev; 574 return (0); 575 } 576 bzero(&pinfo, sizeof(pinfo)); 577 578 /* 579 * We have to open the device before we can perform ioctls on it, 580 * or the slice/label data may not be present. Device opens are 581 * usually tracked by specfs, but the dump device can be set in 582 * early boot and may not be open so this is somewhat of a hack. 583 */ 584 doopen = (dev->si_sysref.refcnt == 1); 585 if (doopen) { 586 error = dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred); 587 if (error) 588 return (error); 589 } 590 error = dev_dioctl(dev, DIOCGPART, (void *)&pinfo, 0, proc0.p_ucred); 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), dumplo64); 666 kprintf("dump "); 667 error = dev_ddump(dumpdev); 668 if (error == 0) { 669 kprintf("succeeded\n"); 670 return; 671 } 672 kprintf("failed, reason: "); 673 switch (error) { 674 case ENOSYS: 675 case ENODEV: 676 kprintf("device doesn't support a dump routine\n"); 677 break; 678 679 case ENXIO: 680 kprintf("device bad\n"); 681 break; 682 683 case EFAULT: 684 kprintf("device not ready\n"); 685 break; 686 687 case EINVAL: 688 kprintf("area improper\n"); 689 break; 690 691 case EIO: 692 kprintf("i/o error\n"); 693 break; 694 695 case EINTR: 696 kprintf("aborted from console\n"); 697 break; 698 699 default: 700 kprintf("unknown, error = %d\n", error); 701 break; 702 } 703 } 704 705 int 706 dumpstatus(vm_offset_t addr, off_t count) 707 { 708 int c; 709 710 if (addr % (1024 * 1024) == 0) { 711 #ifdef HW_WDOG 712 if (wdog_tickler) 713 (*wdog_tickler)(); 714 #endif 715 kprintf("%ld ", (long)(count / (1024 * 1024))); 716 } 717 718 if ((c = cncheckc()) == 0x03) 719 return -1; 720 else if (c != -1) 721 kprintf("[CTRL-C to abort] "); 722 723 return 0; 724 } 725 726 /* 727 * Panic is called on unresolvable fatal errors. It prints "panic: mesg", 728 * and then reboots. If we are called twice, then we avoid trying to sync 729 * the disks as this often leads to recursive panics. 730 */ 731 void 732 panic(const char *fmt, ...) 733 { 734 int bootopt, newpanic; 735 __va_list ap; 736 static char buf[256]; 737 738 #ifdef SMP 739 /* 740 * If a panic occurs on multiple cpus before the first is able to 741 * halt the other cpus, only one cpu is allowed to take the panic. 742 * Attempt to be verbose about this situation but if the kprintf() 743 * itself panics don't let us overrun the kernel stack. 744 * 745 * Be very nasty about descheduling our thread at the lowest 746 * level possible in an attempt to freeze the thread without 747 * inducing further panics. 748 * 749 * Bumping gd_trap_nesting_level will also bypass assertions in 750 * lwkt_switch() and allow us to switch away even if we are a 751 * FAST interrupt or IPI. 752 */ 753 if (atomic_poll_acquire_int(&panic_cpu_interlock)) { 754 panic_cpu_gd = mycpu; 755 } else if (panic_cpu_gd != mycpu) { 756 crit_enter(); 757 ++mycpu->gd_trap_nesting_level; 758 if (mycpu->gd_trap_nesting_level < 25) { 759 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n", 760 mycpu->gd_cpuid, curthread); 761 } 762 curthread->td_release = NULL; /* be a grinch */ 763 for (;;) { 764 lwkt_deschedule_self(curthread); 765 lwkt_switch(); 766 } 767 /* NOT REACHED */ 768 /* --mycpu->gd_trap_nesting_level */ 769 /* crit_exit() */ 770 } 771 #endif 772 bootopt = RB_AUTOBOOT | RB_DUMP; 773 if (sync_on_panic == 0) 774 bootopt |= RB_NOSYNC; 775 newpanic = 0; 776 if (panicstr) 777 bootopt |= RB_NOSYNC; 778 else { 779 panicstr = fmt; 780 newpanic = 1; 781 } 782 783 __va_start(ap, fmt); 784 kvsnprintf(buf, sizeof(buf), fmt, ap); 785 if (panicstr == fmt) 786 panicstr = buf; 787 __va_end(ap); 788 kprintf("panic: %s\n", buf); 789 #ifdef SMP 790 /* two separate prints in case of an unmapped page and trap */ 791 kprintf("mp_lock = %08x; ", mp_lock); 792 kprintf("cpuid = %d\n", mycpu->gd_cpuid); 793 #endif 794 795 #if defined(DDB) 796 if (newpanic && trace_on_panic) 797 db_print_backtrace(); 798 if (debugger_on_panic) 799 Debugger("panic"); 800 #endif 801 boot(bootopt); 802 } 803 804 /* 805 * Support for poweroff delay. 806 */ 807 #ifndef POWEROFF_DELAY 808 # define POWEROFF_DELAY 5000 809 #endif 810 static int poweroff_delay = POWEROFF_DELAY; 811 812 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW, 813 &poweroff_delay, 0, ""); 814 815 static void 816 poweroff_wait(void *junk, int howto) 817 { 818 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0) 819 return; 820 DELAY(poweroff_delay * 1000); 821 } 822 823 /* 824 * Some system processes (e.g. syncer) need to be stopped at appropriate 825 * points in their main loops prior to a system shutdown, so that they 826 * won't interfere with the shutdown process (e.g. by holding a disk buf 827 * to cause sync to fail). For each of these system processes, register 828 * shutdown_kproc() as a handler for one of shutdown events. 829 */ 830 static int kproc_shutdown_wait = 60; 831 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW, 832 &kproc_shutdown_wait, 0, ""); 833 834 void 835 shutdown_kproc(void *arg, int howto) 836 { 837 struct thread *td; 838 struct proc *p; 839 int error; 840 841 if (panicstr) 842 return; 843 844 td = (struct thread *)arg; 845 if ((p = td->td_proc) != NULL) { 846 kprintf("Waiting (max %d seconds) for system process `%s' to stop...", 847 kproc_shutdown_wait, p->p_comm); 848 } else { 849 kprintf("Waiting (max %d seconds) for system thread %s to stop...", 850 kproc_shutdown_wait, td->td_comm); 851 } 852 error = suspend_kproc(td, kproc_shutdown_wait * hz); 853 854 if (error == EWOULDBLOCK) 855 kprintf("timed out\n"); 856 else 857 kprintf("stopped\n"); 858 } 859