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("$FreeBSD$");
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/filedesc.h>
54 #include <sys/jail.h>
55 #include <sys/kdb.h>
56 #include <sys/kernel.h>
57 #include <sys/kerneldump.h>
58 #include <sys/kthread.h>
59 #include <sys/ktr.h>
60 #include <sys/malloc.h>
61 #include <sys/mount.h>
62 #include <sys/priv.h>
63 #include <sys/proc.h>
64 #include <sys/reboot.h>
65 #include <sys/resourcevar.h>
66 #include <sys/rwlock.h>
67 #include <sys/sched.h>
68 #include <sys/smp.h>
69 #include <sys/sysctl.h>
70 #include <sys/sysproto.h>
71 #include <sys/vnode.h>
72 #include <sys/watchdog.h>
73
74 #include <ddb/ddb.h>
75
76 #include <machine/cpu.h>
77 #include <machine/pcb.h>
78 #include <machine/smp.h>
79
80 #include <security/mac/mac_framework.h>
81
82 #include <vm/vm.h>
83 #include <vm/vm_object.h>
84 #include <vm/vm_page.h>
85 #include <vm/vm_pager.h>
86 #include <vm/swap_pager.h>
87
88 #include <sys/signalvar.h>
89
90 #ifndef PANIC_REBOOT_WAIT_TIME
91 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
92 #endif
93 static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
94 SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RW | CTLFLAG_TUN,
95 &panic_reboot_wait_time, 0,
96 "Seconds to wait before rebooting after a panic");
97 TUNABLE_INT("kern.panic_reboot_wait_time", &panic_reboot_wait_time);
98
99 /*
100 * Note that stdarg.h and the ANSI style va_start macro is used for both
101 * ANSI and traditional C compilers.
102 */
103 #include <machine/stdarg.h>
104
105 #ifdef KDB
106 #ifdef KDB_UNATTENDED
107 int debugger_on_panic = 0;
108 #else
109 int debugger_on_panic = 1;
110 #endif
111 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
112 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
113 &debugger_on_panic, 0, "Run debugger on kernel panic");
114 TUNABLE_INT("debug.debugger_on_panic", &debugger_on_panic);
115
116 #ifdef KDB_TRACE
117 static int trace_on_panic = 1;
118 #else
119 static int trace_on_panic = 0;
120 #endif
121 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
122 CTLFLAG_RW | CTLFLAG_SECURE | CTLFLAG_TUN,
123 &trace_on_panic, 0, "Print stack trace on kernel panic");
124 TUNABLE_INT("debug.trace_on_panic", &trace_on_panic);
125 #endif /* KDB */
126
127 static int sync_on_panic = 0;
128 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW | CTLFLAG_TUN,
129 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
130 TUNABLE_INT("kern.sync_on_panic", &sync_on_panic);
131
132 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
133 "Shutdown environment");
134
135 #ifndef DIAGNOSTIC
136 static int show_busybufs;
137 #else
138 static int show_busybufs = 1;
139 #endif
140 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
141 &show_busybufs, 0, "");
142
143 int suspend_blocked = 0;
144 SYSCTL_INT(_kern, OID_AUTO, suspend_blocked, CTLFLAG_RW,
145 &suspend_blocked, 0, "Block suspend due to a pending shutdown");
146
147 /*
148 * Variable panicstr contains argument to first call to panic; used as flag
149 * to indicate that the kernel has already called panic.
150 */
151 const char *panicstr;
152
153 int dumping; /* system is dumping */
154 int rebooting; /* system is rebooting */
155 static struct dumperinfo dumper; /* our selected dumper */
156
157 /* Context information for dump-debuggers. */
158 static struct pcb dumppcb; /* Registers. */
159 lwpid_t dumptid; /* Thread ID. */
160
161 static struct cdevsw reroot_cdevsw = {
162 .d_version = D_VERSION,
163 .d_name = "reroot",
164 };
165
166 static void poweroff_wait(void *, int);
167 static void shutdown_halt(void *junk, int howto);
168 static void shutdown_panic(void *junk, int howto);
169 static void shutdown_reset(void *junk, int howto);
170 static int kern_reroot(void);
171
172 /* register various local shutdown events */
173 static void
174 shutdown_conf(void *unused)
175 {
176
177 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
178 SHUTDOWN_PRI_FIRST);
179 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
180 SHUTDOWN_PRI_LAST + 100);
181 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
182 SHUTDOWN_PRI_LAST + 100);
183 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
184 SHUTDOWN_PRI_LAST + 200);
185 }
186
187 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
188
189 /*
190 * The only reason this exists is to create the /dev/reroot/ directory,
191 * used by reroot code in init(8) as a mountpoint for tmpfs.
192 */
193 static void
194 reroot_conf(void *unused)
195 {
196 int error;
197 struct cdev *cdev;
198
199 error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &cdev,
200 &reroot_cdevsw, NULL, UID_ROOT, GID_WHEEL, 0600, "reroot/reroot");
201 if (error != 0) {
202 printf("%s: failed to create device node, error %d",
203 __func__, error);
204 }
205 }
206
207 SYSINIT(reroot_conf, SI_SUB_DEVFS, SI_ORDER_ANY, reroot_conf, NULL);
208
209 /*
210 * The system call that results in a reboot.
211 */
212 /* ARGSUSED */
213 int
214 sys_reboot(struct thread *td, struct reboot_args *uap)
215 {
216 int error;
217
218 error = 0;
219 #ifdef MAC
220 error = mac_system_check_reboot(td->td_ucred, uap->opt);
221 #endif
222 if (error == 0)
223 error = priv_check(td, PRIV_REBOOT);
224 if (error == 0) {
225 if (uap->opt & RB_REROOT) {
226 error = kern_reroot();
227 } else {
228 mtx_lock(&Giant);
229 kern_reboot(uap->opt);
230 mtx_unlock(&Giant);
231 }
232 }
233 return (error);
234 }
235
236 /*
237 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
238 */
239 static int shutdown_howto = 0;
240
241 void
242 shutdown_nice(int howto)
243 {
244
245 shutdown_howto = howto;
246
247 /* Send a signal to init(8) and have it shutdown the world */
248 if (initproc != NULL) {
249 PROC_LOCK(initproc);
250 kern_psignal(initproc, SIGINT);
251 PROC_UNLOCK(initproc);
252 } else {
253 /* No init(8) running, so simply reboot */
254 kern_reboot(RB_NOSYNC);
255 }
256 return;
257 }
258 static int waittime = -1;
259
260 static void
261 print_uptime(void)
262 {
263 int f;
264 struct timespec ts;
265
266 getnanouptime(&ts);
267 printf("Uptime: ");
268 f = 0;
269 if (ts.tv_sec >= 86400) {
270 printf("%ldd", (long)ts.tv_sec / 86400);
271 ts.tv_sec %= 86400;
272 f = 1;
273 }
274 if (f || ts.tv_sec >= 3600) {
275 printf("%ldh", (long)ts.tv_sec / 3600);
276 ts.tv_sec %= 3600;
277 f = 1;
278 }
279 if (f || ts.tv_sec >= 60) {
280 printf("%ldm", (long)ts.tv_sec / 60);
281 ts.tv_sec %= 60;
282 f = 1;
283 }
284 printf("%lds\n", (long)ts.tv_sec);
285 }
286
287 int
288 doadump(boolean_t textdump)
289 {
290 boolean_t coredump;
291
292 if (dumping)
293 return (EBUSY);
294 if (dumper.dumper == NULL)
295 return (ENXIO);
296
297 savectx(&dumppcb);
298 dumptid = curthread->td_tid;
299 dumping++;
300
301 coredump = TRUE;
302 #ifdef DDB
303 if (textdump && textdump_pending) {
304 coredump = FALSE;
305 textdump_dumpsys(&dumper);
306 }
307 #endif
308 if (coredump)
309 dumpsys(&dumper);
310
311 dumping--;
312 return (0);
313 }
314
315 static int
316 isbufbusy(struct buf *bp)
317 {
318 if (((bp->b_flags & (B_INVAL | B_PERSISTENT)) == 0 &&
319 BUF_ISLOCKED(bp)) ||
320 ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI))
321 return (1);
322 return (0);
323 }
324
325 /*
326 * Shutdown the system cleanly to prepare for reboot, halt, or power off.
327 */
328 void
329 kern_reboot(int howto)
330 {
331 static int first_buf_printf = 1;
332
333 #if defined(SMP)
334 /*
335 * Bind us to CPU 0 so that all shutdown code runs there. Some
336 * systems don't shutdown properly (i.e., ACPI power off) if we
337 * run on another processor.
338 */
339 if (!SCHEDULER_STOPPED()) {
340 thread_lock(curthread);
341 sched_bind(curthread, 0);
342 thread_unlock(curthread);
343 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
344 }
345 #endif
346 /* We're in the process of rebooting. */
347 rebooting = 1;
348
349 /* collect extra flags that shutdown_nice might have set */
350 howto |= shutdown_howto;
351
352 /* We are out of the debugger now. */
353 kdb_active = 0;
354
355 /*
356 * Do any callouts that should be done BEFORE syncing the filesystems.
357 */
358 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
359
360 /*
361 * Now sync filesystems
362 */
363 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
364 register struct buf *bp;
365 int iter, nbusy, pbusy;
366 #ifndef PREEMPTION
367 int subiter;
368 #endif
369
370 waittime = 0;
371
372 wdog_kern_pat(WD_LASTVAL);
373 sys_sync(curthread, NULL);
374
375 /*
376 * With soft updates, some buffers that are
377 * written will be remarked as dirty until other
378 * buffers are written.
379 */
380 for (iter = pbusy = 0; iter < 20; iter++) {
381 nbusy = 0;
382 for (bp = &buf[nbuf]; --bp >= buf; )
383 if (isbufbusy(bp))
384 nbusy++;
385 if (nbusy == 0) {
386 if (first_buf_printf)
387 printf("All buffers synced.");
388 break;
389 }
390 if (first_buf_printf) {
391 printf("Syncing disks, buffers remaining... ");
392 first_buf_printf = 0;
393 }
394 printf("%d ", nbusy);
395 if (nbusy < pbusy)
396 iter = 0;
397 pbusy = nbusy;
398
399 wdog_kern_pat(WD_LASTVAL);
400 sys_sync(curthread, NULL);
401
402 #ifdef PREEMPTION
403 /*
404 * Drop Giant and spin for a while to allow
405 * interrupt threads to run.
406 */
407 DROP_GIANT();
408 DELAY(50000 * iter);
409 PICKUP_GIANT();
410 #else
411 /*
412 * Drop Giant and context switch several times to
413 * allow interrupt threads to run.
414 */
415 DROP_GIANT();
416 for (subiter = 0; subiter < 50 * iter; subiter++) {
417 thread_lock(curthread);
418 mi_switch(SW_VOL, NULL);
419 thread_unlock(curthread);
420 DELAY(1000);
421 }
422 PICKUP_GIANT();
423 #endif
424 }
425 printf("\n");
426 /*
427 * Count only busy local buffers to prevent forcing
428 * a fsck if we're just a client of a wedged NFS server
429 */
430 nbusy = 0;
431 for (bp = &buf[nbuf]; --bp >= buf; ) {
432 if (isbufbusy(bp)) {
433 #if 0
434 /* XXX: This is bogus. We should probably have a BO_REMOTE flag instead */
435 if (bp->b_dev == NULL) {
436 TAILQ_REMOVE(&mountlist,
437 bp->b_vp->v_mount, mnt_list);
438 continue;
439 }
440 #endif
441 nbusy++;
442 if (show_busybufs > 0) {
443 printf(
444 "%d: buf:%p, vnode:%p, flags:%0x, blkno:%jd, lblkno:%jd, buflock:",
445 nbusy, bp, bp->b_vp, bp->b_flags,
446 (intmax_t)bp->b_blkno,
447 (intmax_t)bp->b_lblkno);
448 BUF_LOCKPRINTINFO(bp);
449 if (show_busybufs > 1)
450 vn_printf(bp->b_vp,
451 "vnode content: ");
452 }
453 }
454 }
455 if (nbusy) {
456 /*
457 * Failed to sync all blocks. Indicate this and don't
458 * unmount filesystems (thus forcing an fsck on reboot).
459 */
460 printf("Giving up on %d buffers\n", nbusy);
461 DELAY(5000000); /* 5 seconds */
462 } else {
463 if (!first_buf_printf)
464 printf("Final sync complete\n");
465 /*
466 * Unmount filesystems
467 */
468 if (panicstr == 0)
469 vfs_unmountall();
470 }
471 swapoff_all();
472 DELAY(100000); /* wait for console output to finish */
473 }
474
475 print_uptime();
476
477 cngrab();
478
479 /*
480 * Ok, now do things that assume all filesystem activity has
481 * been completed.
482 */
483 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
484
485 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
486 doadump(TRUE);
487
488 /* Now that we're going to really halt the system... */
489 EVENTHANDLER_INVOKE(shutdown_final, howto);
490
491 for(;;) ; /* safety against shutdown_reset not working */
492 /* NOTREACHED */
493 }
494
495 /*
496 * The system call that results in changing the rootfs.
497 */
498 static int
499 kern_reroot(void)
500 {
501 struct vnode *oldrootvnode, *vp;
502 struct mount *mp, *devmp;
503 int error;
504
505 if (curproc != initproc)
506 return (EPERM);
507
508 /*
509 * Mark the filesystem containing currently-running executable
510 * (the temporary copy of init(8)) busy.
511 */
512 vp = curproc->p_textvp;
513 error = vn_lock(vp, LK_SHARED);
514 if (error != 0)
515 return (error);
516 mp = vp->v_mount;
517 error = vfs_busy(mp, MBF_NOWAIT);
518 if (error != 0) {
519 vfs_ref(mp);
520 VOP_UNLOCK(vp, 0);
521 error = vfs_busy(mp, 0);
522 vn_lock(vp, LK_SHARED | LK_RETRY);
523 vfs_rel(mp);
524 if (error != 0) {
525 VOP_UNLOCK(vp, 0);
526 return (ENOENT);
527 }
528 if (vp->v_iflag & VI_DOOMED) {
529 VOP_UNLOCK(vp, 0);
530 vfs_unbusy(mp);
531 return (ENOENT);
532 }
533 }
534 VOP_UNLOCK(vp, 0);
535
536 /*
537 * Remove the filesystem containing currently-running executable
538 * from the mount list, to prevent it from being unmounted
539 * by vfs_unmountall(), and to avoid confusing vfs_mountroot().
540 *
541 * Also preserve /dev - forcibly unmounting it could cause driver
542 * reinitialization.
543 */
544
545 vfs_ref(rootdevmp);
546 devmp = rootdevmp;
547 rootdevmp = NULL;
548
549 mtx_lock(&mountlist_mtx);
550 TAILQ_REMOVE(&mountlist, mp, mnt_list);
551 TAILQ_REMOVE(&mountlist, devmp, mnt_list);
552 mtx_unlock(&mountlist_mtx);
553
554 oldrootvnode = rootvnode;
555
556 /*
557 * Unmount everything except for the two filesystems preserved above.
558 */
559 vfs_unmountall();
560
561 /*
562 * Add /dev back; vfs_mountroot() will move it into its new place.
563 */
564 mtx_lock(&mountlist_mtx);
565 TAILQ_INSERT_HEAD(&mountlist, devmp, mnt_list);
566 mtx_unlock(&mountlist_mtx);
567 rootdevmp = devmp;
568 vfs_rel(rootdevmp);
569
570 /*
571 * Mount the new rootfs.
572 */
573 vfs_mountroot();
574
575 /*
576 * Update all references to the old rootvnode.
577 */
578 mountcheckdirs(oldrootvnode, rootvnode);
579
580 /*
581 * Add the temporary filesystem back and unbusy it.
582 */
583 mtx_lock(&mountlist_mtx);
584 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
585 mtx_unlock(&mountlist_mtx);
586 vfs_unbusy(mp);
587
588 return (0);
589 }
590
591 /*
592 * If the shutdown was a clean halt, behave accordingly.
593 */
594 static void
595 shutdown_halt(void *junk, int howto)
596 {
597
598 if (howto & RB_HALT) {
599 printf("\n");
600 printf("The operating system has halted.\n");
601 printf("Please press any key to reboot.\n\n");
602 switch (cngetc()) {
603 case -1: /* No console, just die */
604 cpu_halt();
605 /* NOTREACHED */
606 default:
607 howto &= ~RB_HALT;
608 break;
609 }
610 }
611 }
612
613 /*
614 * Check to see if the system paniced, pause and then reboot
615 * according to the specified delay.
616 */
617 static void
618 shutdown_panic(void *junk, int howto)
619 {
620 int loop;
621
622 if (howto & RB_DUMP) {
623 if (panic_reboot_wait_time != 0) {
624 if (panic_reboot_wait_time != -1) {
625 printf("Automatic reboot in %d seconds - "
626 "press a key on the console to abort\n",
627 panic_reboot_wait_time);
628 for (loop = panic_reboot_wait_time * 10;
629 loop > 0; --loop) {
630 DELAY(1000 * 100); /* 1/10th second */
631 /* Did user type a key? */
632 if (cncheckc() != -1)
633 break;
634 }
635 if (!loop)
636 return;
637 }
638 } else { /* zero time specified - reboot NOW */
639 return;
640 }
641 printf("--> Press a key on the console to reboot,\n");
642 printf("--> or switch off the system now.\n");
643 cngetc();
644 }
645 }
646
647 /*
648 * Everything done, now reset
649 */
650 static void
651 shutdown_reset(void *junk, int howto)
652 {
653
654 printf("Rebooting...\n");
655 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
656
657 /*
658 * Acquiring smp_ipi_mtx here has a double effect:
659 * - it disables interrupts avoiding CPU0 preemption
660 * by fast handlers (thus deadlocking against other CPUs)
661 * - it avoids deadlocks against smp_rendezvous() or, more
662 * generally, threads busy-waiting, with this spinlock held,
663 * and waiting for responses by threads on other CPUs
664 * (ie. smp_tlb_shootdown()).
665 *
666 * For the !SMP case it just needs to handle the former problem.
667 */
668 #ifdef SMP
669 mtx_lock_spin(&smp_ipi_mtx);
670 #else
671 spinlock_enter();
672 #endif
673
674 /* cpu_boot(howto); */ /* doesn't do anything at the moment */
675 cpu_reset();
676 /* NOTREACHED */ /* assuming reset worked */
677 }
678
679 #if defined(WITNESS) || defined(INVARIANTS)
680 static int kassert_warn_only = 0;
681 #ifdef KDB
682 static int kassert_do_kdb = 0;
683 #endif
684 #ifdef KTR
685 static int kassert_do_ktr = 0;
686 #endif
687 static int kassert_do_log = 1;
688 static int kassert_log_pps_limit = 4;
689 static int kassert_log_mute_at = 0;
690 static int kassert_log_panic_at = 0;
691 static int kassert_warnings = 0;
692
693 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options");
694
695 SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RW | CTLFLAG_TUN,
696 &kassert_warn_only, 0,
697 "KASSERT triggers a panic (1) or just a warning (0)");
698 TUNABLE_INT("debug.kassert.warn_only", &kassert_warn_only);
699
700 #ifdef KDB
701 SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RW | CTLFLAG_TUN,
702 &kassert_do_kdb, 0, "KASSERT will enter the debugger");
703 TUNABLE_INT("debug.kassert.do_kdb", &kassert_do_kdb);
704 #endif
705
706 #ifdef KTR
707 SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RW | CTLFLAG_TUN,
708 &kassert_do_ktr, 0,
709 "KASSERT does a KTR, set this to the KTRMASK you want");
710 TUNABLE_INT("debug.kassert.do_ktr", &kassert_do_ktr);
711 #endif
712
713 SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RW | CTLFLAG_TUN,
714 &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)");
715 TUNABLE_INT("debug.kassert.do_log", &kassert_do_log);
716
717 SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RW | CTLFLAG_TUN,
718 &kassert_warnings, 0, "number of KASSERTs that have been triggered");
719 TUNABLE_INT("debug.kassert.warnings", &kassert_warnings);
720
721 SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RW | CTLFLAG_TUN,
722 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
723 TUNABLE_INT("debug.kassert.log_panic_at", &kassert_log_panic_at);
724
725 SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RW | CTLFLAG_TUN,
726 &kassert_log_pps_limit, 0, "limit number of log messages per second");
727 TUNABLE_INT("debug.kassert.log_pps_limit", &kassert_log_pps_limit);
728
729 SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RW | CTLFLAG_TUN,
730 &kassert_log_mute_at, 0, "max number of KASSERTS to log");
731 TUNABLE_INT("debug.kassert.log_mute_at", &kassert_log_mute_at);
732
733 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);
734
735 SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert,
736 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
737 kassert_sysctl_kassert, "I", "set to trigger a test kassert");
738
739 static int
740 kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)
741 {
742 int error, i;
743
744 error = sysctl_wire_old_buffer(req, sizeof(int));
745 if (error == 0) {
746 i = 0;
747 error = sysctl_handle_int(oidp, &i, 0, req);
748 }
749 if (error != 0 || req->newptr == NULL)
750 return (error);
751 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i));
752 return (0);
753 }
754
755 /*
756 * Called by KASSERT, this decides if we will panic
757 * or if we will log via printf and/or ktr.
758 */
759 void
760 kassert_panic(const char *fmt, ...)
761 {
762 static char buf[256];
763 va_list ap;
764
765 va_start(ap, fmt);
766 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
767 va_end(ap);
768
769 /*
770 * panic if we're not just warning, or if we've exceeded
771 * kassert_log_panic_at warnings.
772 */
773 if (!kassert_warn_only ||
774 (kassert_log_panic_at > 0 &&
775 kassert_warnings >= kassert_log_panic_at)) {
776 va_start(ap, fmt);
777 vpanic(fmt, ap);
778 /* NORETURN */
779 }
780 #ifdef KTR
781 if (kassert_do_ktr)
782 CTR0(ktr_mask, buf);
783 #endif /* KTR */
784 /*
785 * log if we've not yet met the mute limit.
786 */
787 if (kassert_do_log &&
788 (kassert_log_mute_at == 0 ||
789 kassert_warnings < kassert_log_mute_at)) {
790 static struct timeval lasterr;
791 static int curerr;
792
793 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) {
794 printf("KASSERT failed: %s\n", buf);
795 kdb_backtrace();
796 }
797 }
798 #ifdef KDB
799 if (kassert_do_kdb) {
800 kdb_enter(KDB_WHY_KASSERT, buf);
801 }
802 #endif
803 atomic_add_int(&kassert_warnings, 1);
804 }
805 #endif
806
807 /*
808 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
809 * and then reboots. If we are called twice, then we avoid trying to sync
810 * the disks as this often leads to recursive panics.
811 */
812 void
813 panic(const char *fmt, ...)
814 {
815 va_list ap;
816
817 va_start(ap, fmt);
818 vpanic(fmt, ap);
819 }
820
821 void
822 vpanic(const char *fmt, va_list ap)
823 {
824 #ifdef SMP
825 cpuset_t other_cpus;
826 #endif
827 struct thread *td = curthread;
828 int bootopt, newpanic;
829 static char buf[256];
830
831 spinlock_enter();
832
833 #ifdef SMP
834 /*
835 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from
836 * concurrently entering panic. Only the winner will proceed
837 * further.
838 */
839 if (panicstr == NULL && !kdb_active) {
840 other_cpus = all_cpus;
841 CPU_CLR(PCPU_GET(cpuid), &other_cpus);
842 stop_cpus_hard(other_cpus);
843 }
844
845 /*
846 * We set stop_scheduler here and not in the block above,
847 * because we want to ensure that if panic has been called and
848 * stop_scheduler_on_panic is true, then stop_scheduler will
849 * always be set. Even if panic has been entered from kdb.
850 */
851 td->td_stopsched = 1;
852 #endif
853
854 bootopt = RB_AUTOBOOT;
855 newpanic = 0;
856 if (panicstr)
857 bootopt |= RB_NOSYNC;
858 else {
859 bootopt |= RB_DUMP;
860 panicstr = fmt;
861 newpanic = 1;
862 }
863
864 if (newpanic) {
865 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
866 panicstr = buf;
867 cngrab();
868 printf("panic: %s\n", buf);
869 } else {
870 printf("panic: ");
871 vprintf(fmt, ap);
872 printf("\n");
873 }
874 #ifdef SMP
875 printf("cpuid = %d\n", PCPU_GET(cpuid));
876 #endif
877
878 #ifdef KDB
879 if (newpanic && trace_on_panic)
880 kdb_backtrace();
881 if (debugger_on_panic)
882 kdb_enter(KDB_WHY_PANIC, "panic");
883 #endif
884 /*thread_lock(td); */
885 td->td_flags |= TDF_INPANIC;
886 /* thread_unlock(td); */
887 if (!sync_on_panic)
888 bootopt |= RB_NOSYNC;
889 kern_reboot(bootopt);
890 }
891
892 /*
893 * Support for poweroff delay.
894 *
895 * Please note that setting this delay too short might power off your machine
896 * before the write cache on your hard disk has been flushed, leading to
897 * soft-updates inconsistencies.
898 */
899 #ifndef POWEROFF_DELAY
900 # define POWEROFF_DELAY 5000
901 #endif
902 static int poweroff_delay = POWEROFF_DELAY;
903
904 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
905 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)");
906
907 static void
908 poweroff_wait(void *junk, int howto)
909 {
910
911 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
912 return;
913 DELAY(poweroff_delay * 1000);
914 }
915
916 /*
917 * Some system processes (e.g. syncer) need to be stopped at appropriate
918 * points in their main loops prior to a system shutdown, so that they
919 * won't interfere with the shutdown process (e.g. by holding a disk buf
920 * to cause sync to fail). For each of these system processes, register
921 * shutdown_kproc() as a handler for one of shutdown events.
922 */
923 static int kproc_shutdown_wait = 60;
924 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
925 &kproc_shutdown_wait, 0, "Max wait time (sec) to stop for each process");
926
927 void
928 kproc_shutdown(void *arg, int howto)
929 {
930 struct proc *p;
931 int error;
932
933 if (panicstr)
934 return;
935
936 p = (struct proc *)arg;
937 printf("Waiting (max %d seconds) for system process `%s' to stop...",
938 kproc_shutdown_wait, p->p_comm);
939 error = kproc_suspend(p, kproc_shutdown_wait * hz);
940
941 if (error == EWOULDBLOCK)
942 printf("timed out\n");
943 else
944 printf("done\n");
945 }
946
947 void
948 kthread_shutdown(void *arg, int howto)
949 {
950 struct thread *td;
951 int error;
952
953 if (panicstr)
954 return;
955
956 td = (struct thread *)arg;
957 printf("Waiting (max %d seconds) for system thread `%s' to stop...",
958 kproc_shutdown_wait, td->td_name);
959 error = kthread_suspend(td, kproc_shutdown_wait * hz);
960
961 if (error == EWOULDBLOCK)
962 printf("timed out\n");
963 else
964 printf("done\n");
965 }
966
967 static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)];
968 SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD,
969 dumpdevname, 0, "Device for kernel dumps");
970
971 /* Registration of dumpers */
972 int
973 set_dumper(struct dumperinfo *di, const char *devname, struct thread *td)
974 {
975 size_t wantcopy;
976 int error;
977
978 error = priv_check(td, PRIV_SETDUMPER);
979 if (error != 0)
980 return (error);
981
982 if (di == NULL) {
983 bzero(&dumper, sizeof dumper);
984 dumpdevname[0] = '\0';
985 return (0);
986 }
987 if (dumper.dumper != NULL)
988 return (EBUSY);
989 dumper = *di;
990 wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname));
991 if (wantcopy >= sizeof(dumpdevname)) {
992 printf("set_dumper: device name truncated from '%s' -> '%s'\n",
993 devname, dumpdevname);
994 }
995 return (0);
996 }
997
998 /* Call dumper with bounds checking. */
999 int
1000 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
1001 off_t offset, size_t length)
1002 {
1003
1004 if (length != 0 && (offset < di->mediaoffset ||
1005 offset - di->mediaoffset + length > di->mediasize)) {
1006 printf("Attempt to write outside dump device boundaries.\n"
1007 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
1008 (intmax_t)offset, (intmax_t)di->mediaoffset,
1009 (uintmax_t)length, (intmax_t)di->mediasize);
1010 return (ENOSPC);
1011 }
1012 return (di->dumper(di->priv, virtual, physical, offset, length));
1013 }
1014
1015 void
1016 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
1017 uint64_t dumplen, uint32_t blksz)
1018 {
1019
1020 bzero(kdh, sizeof(*kdh));
1021 strlcpy(kdh->magic, magic, sizeof(kdh->magic));
1022 strlcpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
1023 kdh->version = htod32(KERNELDUMPVERSION);
1024 kdh->architectureversion = htod32(archver);
1025 kdh->dumplength = htod64(dumplen);
1026 kdh->dumptime = htod64(time_second);
1027 kdh->blocksize = htod32(blksz);
1028 strlcpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
1029 strlcpy(kdh->versionstring, version, sizeof(kdh->versionstring));
1030 if (panicstr != NULL)
1031 strlcpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
1032 kdh->parity = kerneldump_parity(kdh);
1033 }
1034
1035 #ifdef DDB
1036 DB_SHOW_COMMAND(panic, db_show_panic)
1037 {
1038
1039 if (panicstr == NULL)
1040 db_printf("panicstr not set\n");
1041 else
1042 db_printf("panic: %s\n", panicstr);
1043 }
1044 #endif
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