1 /*-
2 * Copyright (c) 1986, 1988, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)kern_shutdown.c 8.3 (Berkeley) 1/21/94
35 */
36
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD: releng/10.1/sys/kern/kern_shutdown.c 260431 2014-01-08 02:19:39Z cperciva $");
39
40 #include "opt_ddb.h"
41 #include "opt_kdb.h"
42 #include "opt_panic.h"
43 #include "opt_sched.h"
44 #include "opt_watchdog.h"
45
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/bio.h>
49 #include <sys/buf.h>
50 #include <sys/conf.h>
51 #include <sys/cons.h>
52 #include <sys/eventhandler.h>
53 #include <sys/jail.h>
54 #include <sys/kdb.h>
55 #include <sys/kernel.h>
56 #include <sys/kerneldump.h>
57 #include <sys/kthread.h>
58 #include <sys/ktr.h>
59 #include <sys/malloc.h>
60 #include <sys/mount.h>
61 #include <sys/priv.h>
62 #include <sys/proc.h>
63 #include <sys/reboot.h>
64 #include <sys/resourcevar.h>
65 #include <sys/rwlock.h>
66 #include <sys/sched.h>
67 #include <sys/smp.h>
68 #include <sys/sysctl.h>
69 #include <sys/sysproto.h>
70 #include <sys/vnode.h>
71 #include <sys/watchdog.h>
72
73 #include <ddb/ddb.h>
74
75 #include <machine/cpu.h>
76 #include <machine/pcb.h>
77 #include <machine/smp.h>
78
79 #include <security/mac/mac_framework.h>
80
81 #include <vm/vm.h>
82 #include <vm/vm_object.h>
83 #include <vm/vm_page.h>
84 #include <vm/vm_pager.h>
85 #include <vm/swap_pager.h>
86
87 #include <sys/signalvar.h>
88
89 #ifndef PANIC_REBOOT_WAIT_TIME
90 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
91 #endif
92 static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
93 SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RW | CTLFLAG_TUN,
94 &panic_reboot_wait_time, 0,
95 "Seconds to wait before rebooting after a panic");
96 TUNABLE_INT("kern.panic_reboot_wait_time", &panic_reboot_wait_time);
97
98 /*
99 * Note that stdarg.h and the ANSI style va_start macro is used for both
100 * ANSI and traditional C compilers.
101 */
102 #include <machine/stdarg.h>
103
104 #ifdef KDB
105 #ifdef KDB_UNATTENDED
106 int debugger_on_panic = 0;
107 #else
108 int debugger_on_panic = 1;
109 #endif
110 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
111 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
112 &debugger_on_panic, 0, "Run debugger on kernel panic");
113 TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic);
114
115 #ifdef KDB_TRACE
116 static int trace_on_panic = 1;
117 #else
118 static int trace_on_panic = 0;
119 #endif
120 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
121 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
122 &trace_on_panic, 0, "Print stack trace on kernel panic");
123 TUNABLE_INT("debug.trace_on_panic", &trace_on_panic);
124 #endif /* KDB */
125
126 static int sync_on_panic = 0;
127 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
128 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
129 TUNABLE_INT("kern.sync_on_panic", &sync_on_panic);
130
131 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
132 "Shutdown environment");
133
134 #ifndef DIAGNOSTIC
135 static int show_busybufs;
136 #else
137 static int show_busybufs = 1;
138 #endif
139 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
140 &show_busybufs, 0, "");
141
142 /*
143 * Variable panicstr contains argument to first call to panic; used as flag
144 * to indicate that the kernel has already called panic.
145 */
146 const char *panicstr;
147
148 int dumping; /* system is dumping */
149 int rebooting; /* system is rebooting */
150 static struct dumperinfo dumper; /* our selected dumper */
151
152 /* Context information for dump-debuggers. */
153 static struct pcb dumppcb; /* Registers. */
154 lwpid_t dumptid; /* Thread ID. */
155
156 static void poweroff_wait(void *, int);
157 static void shutdown_halt(void *junk, int howto);
158 static void shutdown_panic(void *junk, int howto);
159 static void shutdown_reset(void *junk, int howto);
160 static void vpanic(const char *fmt, va_list ap) __dead2;
161
162 /* register various local shutdown events */
163 static void
164 shutdown_conf(void *unused)
165 {
166
167 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
168 SHUTDOWN_PRI_FIRST);
169 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
170 SHUTDOWN_PRI_LAST + 100);
171 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
172 SHUTDOWN_PRI_LAST + 100);
173 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
174 SHUTDOWN_PRI_LAST + 200);
175 }
176
177 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
178
179 /*
180 * The system call that results in a reboot.
181 */
182 /* ARGSUSED */
183 int
184 sys_reboot(struct thread *td, struct reboot_args *uap)
185 {
186 int error;
187
188 error = 0;
189 #ifdef MAC
190 error = mac_system_check_reboot(td->td_ucred, uap->opt);
191 #endif
192 if (error == 0)
193 error = priv_check(td, PRIV_REBOOT);
194 if (error == 0) {
195 mtx_lock(&Giant);
196 kern_reboot(uap->opt);
197 mtx_unlock(&Giant);
198 }
199 return (error);
200 }
201
202 /*
203 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
204 */
205 static int shutdown_howto = 0;
206
207 void
208 shutdown_nice(int howto)
209 {
210
211 shutdown_howto = howto;
212
213 /* Send a signal to init(8) and have it shutdown the world */
214 if (initproc != NULL) {
215 PROC_LOCK(initproc);
216 kern_psignal(initproc, SIGINT);
217 PROC_UNLOCK(initproc);
218 } else {
219 /* No init(8) running, so simply reboot */
220 kern_reboot(RB_NOSYNC);
221 }
222 return;
223 }
224 static int waittime = -1;
225
226 static void
227 print_uptime(void)
228 {
229 int f;
230 struct timespec ts;
231
232 getnanouptime(&ts);
233 printf("Uptime: ");
234 f = 0;
235 if (ts.tv_sec >= 86400) {
236 printf("%ldd", (long)ts.tv_sec / 86400);
237 ts.tv_sec %= 86400;
238 f = 1;
239 }
240 if (f || ts.tv_sec >= 3600) {
241 printf("%ldh", (long)ts.tv_sec / 3600);
242 ts.tv_sec %= 3600;
243 f = 1;
244 }
245 if (f || ts.tv_sec >= 60) {
246 printf("%ldm", (long)ts.tv_sec / 60);
247 ts.tv_sec %= 60;
248 f = 1;
249 }
250 printf("%lds\n", (long)ts.tv_sec);
251 }
252
253 int
254 doadump(boolean_t textdump)
255 {
256 boolean_t coredump;
257
258 if (dumping)
259 return (EBUSY);
260 if (dumper.dumper == NULL)
261 return (ENXIO);
262
263 savectx(&dumppcb);
264 dumptid = curthread->td_tid;
265 dumping++;
266
267 coredump = TRUE;
268 #ifdef DDB
269 if (textdump && textdump_pending) {
270 coredump = FALSE;
271 textdump_dumpsys(&dumper);
272 }
273 #endif
274 if (coredump)
275 dumpsys(&dumper);
276
277 dumping--;
278 return (0);
279 }
280
281 static int
282 isbufbusy(struct buf *bp)
283 {
284 if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
285 BUF_ISLOCKED(bp)) ||
286 ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
287 return (1);
288 return (0);
289 }
290
291 /*
292 * Shutdown the system cleanly to prepare for reboot, halt, or power off.
293 */
294 void
295 kern_reboot(int howto)
296 {
297 static int first_buf_printf = 1;
298
299 #if defined(SMP)
300 /*
301 * Bind us to CPU 0 so that all shutdown code runs there. Some
302 * systems don't shutdown properly (i.e., ACPI power off) if we
303 * run on another processor.
304 */
305 if (!SCHEDULER_STOPPED()) {
306 thread_lock(curthread);
307 sched_bind(curthread, 0);
308 thread_unlock(curthread);
309 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
310 }
311 #endif
312 /* We're in the process of rebooting. */
313 rebooting = 1;
314
315 /* collect extra flags that shutdown_nice might have set */
316 howto |= shutdown_howto;
317
318 /* We are out of the debugger now. */
319 kdb_active = 0;
320
321 /*
322 * Do any callouts that should be done BEFORE syncing the filesystems.
323 */
324 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
325
326 /*
327 * Now sync filesystems
328 */
329 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
330 register struct buf *bp;
331 int iter, nbusy, pbusy;
332 #ifndef PREEMPTION
333 int subiter;
334 #endif
335
336 waittime = 0;
337
338 wdog_kern_pat(WD_LASTVAL);
339 sys_sync(curthread, NULL);
340
341 /*
342 * With soft updates, some buffers that are
343 * written will be remarked as dirty until other
344 * buffers are written.
345 */
346 for (iter = pbusy = 0; iter < 20; iter++) {
347 nbusy = 0;
348 for (bp = &buf[nbuf]; --bp >= buf; )
349 if (isbufbusy(bp))
350 nbusy++;
351 if (nbusy == 0) {
352 if (first_buf_printf)
353 printf("All buffers synced.");
354 break;
355 }
356 if (first_buf_printf) {
357 printf("Syncing disks, buffers remaining... ");
358 first_buf_printf = 0;
359 }
360 printf("%d ", nbusy);
361 if (nbusy < pbusy)
362 iter = 0;
363 pbusy = nbusy;
364
365 wdog_kern_pat(WD_LASTVAL);
366 sys_sync(curthread, NULL);
367
368 #ifdef PREEMPTION
369 /*
370 * Drop Giant and spin for a while to allow
371 * interrupt threads to run.
372 */
373 DROP_GIANT();
374 DELAY(50000 * iter);
375 PICKUP_GIANT();
376 #else
377 /*
378 * Drop Giant and context switch several times to
379 * allow interrupt threads to run.
380 */
381 DROP_GIANT();
382 for (subiter = 0; subiter < 50 * iter; subiter++) {
383 thread_lock(curthread);
384 mi_switch(SW_VOL, NULL);
385 thread_unlock(curthread);
386 DELAY(1000);
387 }
388 PICKUP_GIANT();
389 #endif
390 }
391 printf("\n");
392 /*
393 * Count only busy local buffers to prevent forcing
394 * a fsck if we're just a client of a wedged NFS server
395 */
396 nbusy = 0;
397 for (bp = &buf[nbuf]; --bp >= buf; ) {
398 if (isbufbusy(bp)) {
399 #if 0
400 /* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */
401 if (bp->b_dev == NULL) {
402 TAILQ_REMOVE(&mountlist,
403 bp->b_vp->v_mount, mnt_list);
404 continue;
405 }
406 #endif
407 nbusy++;
408 if (show_busybufs > 0) {
409 printf(
410 "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
411 nbusy, bp, bp->b_vp, bp->b_flags,
412 (intmax_t)bp->b_blkno,
413 (intmax_t)bp->b_lblkno);
414 BUF_LOCKPRINTINFO(bp);
415 if (show_busybufs > 1)
416 vn_printf(bp->b_vp,
417 "vnode content: ");
418 }
419 }
420 }
421 if (nbusy) {
422 /*
423 * Failed to sync all blocks. Indicate this and don't
424 * unmount filesystems (thus forcing an fsck on reboot).
425 */
426 printf("Giving up on %d buffers\n", nbusy);
427 DELAY(5000000); /* 5 seconds */
428 } else {
429 if (!first_buf_printf)
430 printf("Final sync complete\n");
431 /*
432 * Unmount filesystems
433 */
434 if (panicstr == 0)
435 vfs_unmountall();
436 }
437 swapoff_all();
438 DELAY(100000); /* wait for console output to finish */
439 }
440
441 print_uptime();
442
443 cngrab();
444
445 /*
446 * Ok, now do things that assume all filesystem activity has
447 * been completed.
448 */
449 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
450
451 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
452 doadump(TRUE);
453
454 /* Now that we're going to really halt the system... */
455 EVENTHANDLER_INVOKE(shutdown_final, howto);
456
457 for(;;) ; /* safety against shutdown_reset not working */
458 /* NOTREACHED */
459 }
460
461 /*
462 * If the shutdown was a clean halt, behave accordingly.
463 */
464 static void
465 shutdown_halt(void *junk, int howto)
466 {
467
468 if (howto & RB_HALT) {
469 printf("\n");
470 printf("The operating system has halted.\n");
471 printf("Please press any key to reboot.\n\n");
472 switch (cngetc()) {
473 case -1: /* No console, just die */
474 cpu_halt();
475 /* NOTREACHED */
476 default:
477 howto &= ~RB_HALT;
478 break;
479 }
480 }
481 }
482
483 /*
484 * Check to see if the system paniced, pause and then reboot
485 * according to the specified delay.
486 */
487 static void
488 shutdown_panic(void *junk, int howto)
489 {
490 int loop;
491
492 if (howto & RB_DUMP) {
493 if (panic_reboot_wait_time != 0) {
494 if (panic_reboot_wait_time != -1) {
495 printf("Automatic reboot in %d seconds - "
496 "press a key on the console to abort\n",
497 panic_reboot_wait_time);
498 for (loop = panic_reboot_wait_time * 10;
499 loop > 0; --loop) {
500 DELAY(1000 * 100); /* 1/10th second */
501 /* Did user type a key? */
502 if (cncheckc() != -1)
503 break;
504 }
505 if (!loop)
506 return;
507 }
508 } else { /* zero time specified - reboot NOW */
509 return;
510 }
511 printf("--> Press a key on the console to reboot,\n");
512 printf("--> or switch off the system now.\n");
513 cngetc();
514 }
515 }
516
517 /*
518 * Everything done, now reset
519 */
520 static void
521 shutdown_reset(void *junk, int howto)
522 {
523
524 printf("Rebooting...\n");
525 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
526
527 /*
528 * Acquiring smp_ipi_mtx here has a double effect:
529 * - it disables interrupts avoiding CPU0 preemption
530 * by fast handlers (thus deadlocking against other CPUs)
531 * - it avoids deadlocks against smp_rendezvous() or, more
532 * generally, threads busy-waiting, with this spinlock held,
533 * and waiting for responses by threads on other CPUs
534 * (ie. smp_tlb_shootdown()).
535 *
536 * For the !SMP case it just needs to handle the former problem.
537 */
538 #ifdef SMP
539 mtx_lock_spin(&smp_ipi_mtx);
540 #else
541 spinlock_enter();
542 #endif
543
544 /* cpu_boot(howto); */ /* doesn't do anything at the moment */
545 cpu_reset();
546 /* NOTREACHED */ /* assuming reset worked */
547 }
548
549 #if defined(WITNESS) || defined(INVARIANTS)
550 static int kassert_warn_only = 0;
551 #ifdef KDB
552 static int kassert_do_kdb = 0;
553 #endif
554 #ifdef KTR
555 static int kassert_do_ktr = 0;
556 #endif
557 static int kassert_do_log = 1;
558 static int kassert_log_pps_limit = 4;
559 static int kassert_log_mute_at = 0;
560 static int kassert_log_panic_at = 0;
561 static int kassert_warnings = 0;
562
563 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options");
564
565 SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RW | CTLFLAG_TUN,
566 &kassert_warn_only, 0,
567 "KASSERT triggers a panic (1) or just a warning (0)");
568 TUNABLE_INT("debug.kassert.warn_only", &kassert_warn_only);
569
570 #ifdef KDB
571 SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RW | CTLFLAG_TUN,
572 &kassert_do_kdb, 0, "KASSERT will enter the debugger");
573 TUNABLE_INT("debug.kassert.do_kdb", &kassert_do_kdb);
574 #endif
575
576 #ifdef KTR
577 SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RW | CTLFLAG_TUN,
578 &kassert_do_ktr, 0,
579 "KASSERT does a KTR, set this to the KTRMASK you want");
580 TUNABLE_INT("debug.kassert.do_ktr", &kassert_do_ktr);
581 #endif
582
583 SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RW | CTLFLAG_TUN,
584 &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)");
585 TUNABLE_INT("debug.kassert.do_log", &kassert_do_log);
586
587 SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RW | CTLFLAG_TUN,
588 &kassert_warnings, 0, "number of KASSERTs that have been triggered");
589 TUNABLE_INT("debug.kassert.warnings", &kassert_warnings);
590
591 SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RW | CTLFLAG_TUN,
592 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
593 TUNABLE_INT("debug.kassert.log_panic_at", &kassert_log_panic_at);
594
595 SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RW | CTLFLAG_TUN,
596 &kassert_log_pps_limit, 0, "limit number of log messages per second");
597 TUNABLE_INT("debug.kassert.log_pps_limit", &kassert_log_pps_limit);
598
599 SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RW | CTLFLAG_TUN,
600 &kassert_log_mute_at, 0, "max number of KASSERTS to log");
601 TUNABLE_INT("debug.kassert.log_mute_at", &kassert_log_mute_at);
602
603 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);
604
605 SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert,
606 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
607 kassert_sysctl_kassert, "I", "set to trigger a test kassert");
608
609 static int
610 kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)
611 {
612 int error, i;
613
614 error = sysctl_wire_old_buffer(req, sizeof(int));
615 if (error == 0) {
616 i = 0;
617 error = sysctl_handle_int(oidp, &i, 0, req);
618 }
619 if (error != 0 || req->newptr == NULL)
620 return (error);
621 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i));
622 return (0);
623 }
624
625 /*
626 * Called by KASSERT, this decides if we will panic
627 * or if we will log via printf and/or ktr.
628 */
629 void
630 kassert_panic(const char *fmt, ...)
631 {
632 static char buf[256];
633 va_list ap;
634
635 va_start(ap, fmt);
636 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
637 va_end(ap);
638
639 /*
640 * panic if we're not just warning, or if we've exceeded
641 * kassert_log_panic_at warnings.
642 */
643 if (!kassert_warn_only ||
644 (kassert_log_panic_at > 0 &&
645 kassert_warnings >= kassert_log_panic_at)) {
646 va_start(ap, fmt);
647 vpanic(fmt, ap);
648 /* NORETURN */
649 }
650 #ifdef KTR
651 if (kassert_do_ktr)
652 CTR0(ktr_mask, buf);
653 #endif /* KTR */
654 /*
655 * log if we've not yet met the mute limit.
656 */
657 if (kassert_do_log &&
658 (kassert_log_mute_at == 0 ||
659 kassert_warnings < kassert_log_mute_at)) {
660 static struct timeval lasterr;
661 static int curerr;
662
663 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) {
664 printf("KASSERT failed: %s\n", buf);
665 kdb_backtrace();
666 }
667 }
668 #ifdef KDB
669 if (kassert_do_kdb) {
670 kdb_enter(KDB_WHY_KASSERT, buf);
671 }
672 #endif
673 atomic_add_int(&kassert_warnings, 1);
674 }
675 #endif
676
677 /*
678 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
679 * and then reboots. If we are called twice, then we avoid trying to sync
680 * the disks as this often leads to recursive panics.
681 */
682 void
683 panic(const char *fmt, ...)
684 {
685 va_list ap;
686
687 va_start(ap, fmt);
688 vpanic(fmt, ap);
689 }
690
691 static void
692 vpanic(const char *fmt, va_list ap)
693 {
694 #ifdef SMP
695 cpuset_t other_cpus;
696 #endif
697 struct thread *td = curthread;
698 int bootopt, newpanic;
699 static char buf[256];
700
701 spinlock_enter();
702
703 #ifdef SMP
704 /*
705 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from
706 * concurrently entering panic. Only the winner will proceed
707 * further.
708 */
709 if (panicstr == NULL && !kdb_active) {
710 other_cpus = all_cpus;
711 CPU_CLR(PCPU_GET(cpuid), &other_cpus);
712 stop_cpus_hard(other_cpus);
713 }
714
715 /*
716 * We set stop_scheduler here and not in the block above,
717 * because we want to ensure that if panic has been called and
718 * stop_scheduler_on_panic is true, then stop_scheduler will
719 * always be set. Even if panic has been entered from kdb.
720 */
721 td->td_stopsched = 1;
722 #endif
723
724 bootopt = RB_AUTOBOOT;
725 newpanic = 0;
726 if (panicstr)
727 bootopt |= RB_NOSYNC;
728 else {
729 bootopt |= RB_DUMP;
730 panicstr = fmt;
731 newpanic = 1;
732 }
733
734 if (newpanic) {
735 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
736 panicstr = buf;
737 cngrab();
738 printf("panic: %s\n", buf);
739 } else {
740 printf("panic: ");
741 vprintf(fmt, ap);
742 printf("\n");
743 }
744 #ifdef SMP
745 printf("cpuid = %d\n", PCPU_GET(cpuid));
746 #endif
747
748 #ifdef KDB
749 if (newpanic && trace_on_panic)
750 kdb_backtrace();
751 if (debugger_on_panic)
752 kdb_enter(KDB_WHY_PANIC, "panic");
753 #endif
754 /*thread_lock(td); */
755 td->td_flags |= TDF_INPANIC;
756 /* thread_unlock(td); */
757 if (!sync_on_panic)
758 bootopt |= RB_NOSYNC;
759 kern_reboot(bootopt);
760 }
761
762 /*
763 * Support for poweroff delay.
764 *
765 * Please note that setting this delay too short might power off your machine
766 * before the write cache on your hard disk has been flushed, leading to
767 * soft-updates inconsistencies.
768 */
769 #ifndef POWEROFF_DELAY
770 # define POWEROFF_DELAY 5000
771 #endif
772 static int poweroff_delay = POWEROFF_DELAY;
773
774 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
775 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)");
776
777 static void
778 poweroff_wait(void *junk, int howto)
779 {
780
781 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
782 return;
783 DELAY(poweroff_delay * 1000);
784 }
785
786 /*
787 * Some system processes (e.g. syncer) need to be stopped at appropriate
788 * points in their main loops prior to a system shutdown, so that they
789 * won't interfere with the shutdown process (e.g. by holding a disk buf
790 * to cause sync to fail). For each of these system processes, register
791 * shutdown_kproc() as a handler for one of shutdown events.
792 */
793 static int kproc_shutdown_wait = 60;
794 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
795 &kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process");
796
797 void
798 kproc_shutdown(void *arg, int howto)
799 {
800 struct proc *p;
801 int error;
802
803 if (panicstr)
804 return;
805
806 p = (struct proc *)arg;
807 printf("Waiting (max %d seconds) for system process `%s' to stop...",
808 kproc_shutdown_wait, p->p_comm);
809 error = kproc_suspend(p, kproc_shutdown_wait * hz);
810
811 if (error == EWOULDBLOCK)
812 printf("timed out\n");
813 else
814 printf("done\n");
815 }
816
817 void
818 kthread_shutdown(void *arg, int howto)
819 {
820 struct thread *td;
821 int error;
822
823 if (panicstr)
824 return;
825
826 td = (struct thread *)arg;
827 printf("Waiting (max %d seconds) for system thread `%s' to stop...",
828 kproc_shutdown_wait, td->td_name);
829 error = kthread_suspend(td, kproc_shutdown_wait * hz);
830
831 if (error == EWOULDBLOCK)
832 printf("timed out\n");
833 else
834 printf("done\n");
835 }
836
837 static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)];
838 SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD,
839 dumpdevname, 0, "Device for kernel dumps");
840
841 /* Registration of dumpers */
842 int
843 set_dumper(struct dumperinfo *di, const char *devname)
844 {
845 size_t wantcopy;
846
847 if (di == NULL) {
848 bzero(&dumper, sizeof dumper);
849 dumpdevname[0] = '\0';
850 return (0);
851 }
852 if (dumper.dumper != NULL)
853 return (EBUSY);
854 dumper = *di;
855 wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname));
856 if (wantcopy >= sizeof(dumpdevname)) {
857 printf("set_dumper: device name truncated from '%s' -> '%s'\n",
858 devname, dumpdevname);
859 }
860 return (0);
861 }
862
863 /* Call dumper with bounds checking. */
864 int
865 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
866 off_t offset, size_t length)
867 {
868
869 if (length != 0 && (offset < di->mediaoffset ||
870 offset - di->mediaoffset + length > di->mediasize)) {
871 printf("Attempt to write outside dump device boundaries.\n"
872 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
873 (intmax_t)offset, (intmax_t)di->mediaoffset,
874 (uintmax_t)length, (intmax_t)di->mediasize);
875 return (ENOSPC);
876 }
877 return (di->dumper(di->priv, virtual, physical, offset, length));
878 }
879
880 void
881 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
882 uint64_t dumplen, uint32_t blksz)
883 {
884
885 bzero(kdh, sizeof(*kdh));
886 strncpy(kdh->magic, magic, sizeof(kdh->magic));
887 strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
888 kdh->version = htod32(KERNELDUMPVERSION);
889 kdh->architectureversion = htod32(archver);
890 kdh->dumplength = htod64(dumplen);
891 kdh->dumptime = htod64(time_second);
892 kdh->blocksize = htod32(blksz);
893 strncpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
894 strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
895 if (panicstr != NULL)
896 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
897 kdh->parity = kerneldump_parity(kdh);
898 }
Cache object: 30cf249ced8a64ed201620c0e367b5c9
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