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
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7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
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34 * @(#)kern_shutdown.c 8.3 (Berkeley) 1/21/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
42 #include "opt_panic.h"
43 #include "opt_sched.h"
44 #include "opt_watchdog.h"
46 #include <sys/param.h>
47 #include <sys/systm.h>
52 #include <sys/eventhandler.h>
53 #include <sys/filedesc.h>
56 #include <sys/kernel.h>
57 #include <sys/kerneldump.h>
58 #include <sys/kthread.h>
60 #include <sys/malloc.h>
61 #include <sys/mount.h>
64 #include <sys/reboot.h>
65 #include <sys/resourcevar.h>
66 #include <sys/rwlock.h>
67 #include <sys/sched.h>
69 #include <sys/sysctl.h>
70 #include <sys/sysproto.h>
71 #include <sys/vnode.h>
72 #include <sys/watchdog.h>
76 #include <machine/cpu.h>
77 #include <machine/dump.h>
78 #include <machine/pcb.h>
79 #include <machine/smp.h>
81 #include <security/mac/mac_framework.h>
84 #include <vm/vm_object.h>
85 #include <vm/vm_page.h>
86 #include <vm/vm_pager.h>
87 #include <vm/swap_pager.h>
89 #include <sys/signalvar.h>
91 static MALLOC_DEFINE(M_DUMPER, "dumper", "dumper block buffer");
93 #ifndef PANIC_REBOOT_WAIT_TIME
94 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
96 static int panic_reboot_wait_time = PANIC_REBOOT_WAIT_TIME;
97 SYSCTL_INT(_kern, OID_AUTO, panic_reboot_wait_time, CTLFLAG_RWTUN,
98 &panic_reboot_wait_time, 0,
99 "Seconds to wait before rebooting after a panic");
102 * Note that stdarg.h and the ANSI style va_start macro is used for both
103 * ANSI and traditional C compilers.
105 #include <machine/stdarg.h>
108 #ifdef KDB_UNATTENDED
109 int debugger_on_panic = 0;
111 int debugger_on_panic = 1;
113 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic,
114 CTLFLAG_RWTUN | CTLFLAG_SECURE,
115 &debugger_on_panic, 0, "Run debugger on kernel panic");
118 static int trace_on_panic = 1;
120 static int trace_on_panic = 0;
122 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic,
123 CTLFLAG_RWTUN | CTLFLAG_SECURE,
124 &trace_on_panic, 0, "Print stack trace on kernel panic");
127 static int sync_on_panic = 0;
128 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RWTUN,
129 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
131 static SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0,
132 "Shutdown environment");
135 static int show_busybufs;
137 static int show_busybufs = 1;
139 SYSCTL_INT(_kern_shutdown, OID_AUTO, show_busybufs, CTLFLAG_RW,
140 &show_busybufs, 0, "");
142 int suspend_blocked = 0;
143 SYSCTL_INT(_kern, OID_AUTO, suspend_blocked, CTLFLAG_RW,
144 &suspend_blocked, 0, "Block suspend due to a pending shutdown");
147 * Variable panicstr contains argument to first call to panic; used as flag
148 * to indicate that the kernel has already called panic.
150 const char *panicstr;
152 int dumping; /* system is dumping */
153 int rebooting; /* system is rebooting */
154 static struct dumperinfo dumper; /* our selected dumper */
156 /* Context information for dump-debuggers. */
157 static struct pcb dumppcb; /* Registers. */
158 lwpid_t dumptid; /* Thread ID. */
160 static struct cdevsw reroot_cdevsw = {
161 .d_version = D_VERSION,
165 static void poweroff_wait(void *, int);
166 static void shutdown_halt(void *junk, int howto);
167 static void shutdown_panic(void *junk, int howto);
168 static void shutdown_reset(void *junk, int howto);
169 static int kern_reroot(void);
171 /* register various local shutdown events */
173 shutdown_conf(void *unused)
176 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL,
178 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL,
179 SHUTDOWN_PRI_LAST + 100);
180 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL,
181 SHUTDOWN_PRI_LAST + 100);
182 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL,
183 SHUTDOWN_PRI_LAST + 200);
186 SYSINIT(shutdown_conf, SI_SUB_INTRINSIC, SI_ORDER_ANY, shutdown_conf, NULL);
189 * The only reason this exists is to create the /dev/reroot/ directory,
190 * used by reroot code in init(8) as a mountpoint for tmpfs.
193 reroot_conf(void *unused)
198 error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &cdev,
199 &reroot_cdevsw, NULL, UID_ROOT, GID_WHEEL, 0600, "reroot/reroot");
201 printf("%s: failed to create device node, error %d",
206 SYSINIT(reroot_conf, SI_SUB_DEVFS, SI_ORDER_ANY, reroot_conf, NULL);
209 * The system call that results in a reboot.
213 sys_reboot(struct thread *td, struct reboot_args *uap)
219 error = mac_system_check_reboot(td->td_ucred, uap->opt);
222 error = priv_check(td, PRIV_REBOOT);
224 if (uap->opt & RB_REROOT) {
225 error = kern_reroot();
228 kern_reboot(uap->opt);
236 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
239 shutdown_nice(int howto)
242 if (initproc != NULL) {
243 /* Send a signal to init(8) and have it shutdown the world. */
245 if (howto & RB_POWEROFF)
246 kern_psignal(initproc, SIGUSR2);
247 else if (howto & RB_HALT)
248 kern_psignal(initproc, SIGUSR1);
250 kern_psignal(initproc, SIGINT);
251 PROC_UNLOCK(initproc);
253 /* No init(8) running, so simply reboot. */
254 kern_reboot(howto | RB_NOSYNC);
267 if (ts.tv_sec >= 86400) {
268 printf("%ldd", (long)ts.tv_sec / 86400);
272 if (f || ts.tv_sec >= 3600) {
273 printf("%ldh", (long)ts.tv_sec / 3600);
277 if (f || ts.tv_sec >= 60) {
278 printf("%ldm", (long)ts.tv_sec / 60);
282 printf("%lds\n", (long)ts.tv_sec);
286 doadump(boolean_t textdump)
294 if (dumper.dumper == NULL)
298 dumptid = curthread->td_tid;
303 if (textdump && textdump_pending) {
305 textdump_dumpsys(&dumper);
309 error = dumpsys(&dumper);
316 * Shutdown the system cleanly to prepare for reboot, halt, or power off.
319 kern_reboot(int howto)
325 * Bind us to CPU 0 so that all shutdown code runs there. Some
326 * systems don't shutdown properly (i.e., ACPI power off) if we
327 * run on another processor.
329 if (!SCHEDULER_STOPPED()) {
330 thread_lock(curthread);
331 sched_bind(curthread, 0);
332 thread_unlock(curthread);
333 KASSERT(PCPU_GET(cpuid) == 0, ("boot: not running on cpu 0"));
336 /* We're in the process of rebooting. */
339 /* We are out of the debugger now. */
343 * Do any callouts that should be done BEFORE syncing the filesystems.
345 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
348 * Now sync filesystems
350 if (!cold && (howto & RB_NOSYNC) == 0 && once == 0) {
352 bufshutdown(show_busybufs);
360 * Ok, now do things that assume all filesystem activity has
363 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
365 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold && !dumping)
368 /* Now that we're going to really halt the system... */
369 EVENTHANDLER_INVOKE(shutdown_final, howto);
371 for(;;) ; /* safety against shutdown_reset not working */
376 * The system call that results in changing the rootfs.
381 struct vnode *oldrootvnode, *vp;
382 struct mount *mp, *devmp;
385 if (curproc != initproc)
389 * Mark the filesystem containing currently-running executable
390 * (the temporary copy of init(8)) busy.
392 vp = curproc->p_textvp;
393 error = vn_lock(vp, LK_SHARED);
397 error = vfs_busy(mp, MBF_NOWAIT);
401 error = vfs_busy(mp, 0);
402 vn_lock(vp, LK_SHARED | LK_RETRY);
408 if (vp->v_iflag & VI_DOOMED) {
417 * Remove the filesystem containing currently-running executable
418 * from the mount list, to prevent it from being unmounted
419 * by vfs_unmountall(), and to avoid confusing vfs_mountroot().
421 * Also preserve /dev - forcibly unmounting it could cause driver
429 mtx_lock(&mountlist_mtx);
430 TAILQ_REMOVE(&mountlist, mp, mnt_list);
431 TAILQ_REMOVE(&mountlist, devmp, mnt_list);
432 mtx_unlock(&mountlist_mtx);
434 oldrootvnode = rootvnode;
437 * Unmount everything except for the two filesystems preserved above.
442 * Add /dev back; vfs_mountroot() will move it into its new place.
444 mtx_lock(&mountlist_mtx);
445 TAILQ_INSERT_HEAD(&mountlist, devmp, mnt_list);
446 mtx_unlock(&mountlist_mtx);
451 * Mount the new rootfs.
456 * Update all references to the old rootvnode.
458 mountcheckdirs(oldrootvnode, rootvnode);
461 * Add the temporary filesystem back and unbusy it.
463 mtx_lock(&mountlist_mtx);
464 TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
465 mtx_unlock(&mountlist_mtx);
472 * If the shutdown was a clean halt, behave accordingly.
475 shutdown_halt(void *junk, int howto)
478 if (howto & RB_HALT) {
480 printf("The operating system has halted.\n");
481 printf("Please press any key to reboot.\n\n");
483 case -1: /* No console, just die */
494 * Check to see if the system paniced, pause and then reboot
495 * according to the specified delay.
498 shutdown_panic(void *junk, int howto)
502 if (howto & RB_DUMP) {
503 if (panic_reboot_wait_time != 0) {
504 if (panic_reboot_wait_time != -1) {
505 printf("Automatic reboot in %d seconds - "
506 "press a key on the console to abort\n",
507 panic_reboot_wait_time);
508 for (loop = panic_reboot_wait_time * 10;
510 DELAY(1000 * 100); /* 1/10th second */
511 /* Did user type a key? */
512 if (cncheckc() != -1)
518 } else { /* zero time specified - reboot NOW */
521 printf("--> Press a key on the console to reboot,\n");
522 printf("--> or switch off the system now.\n");
528 * Everything done, now reset
531 shutdown_reset(void *junk, int howto)
534 printf("Rebooting...\n");
535 DELAY(1000000); /* wait 1 sec for printf's to complete and be read */
538 * Acquiring smp_ipi_mtx here has a double effect:
539 * - it disables interrupts avoiding CPU0 preemption
540 * by fast handlers (thus deadlocking against other CPUs)
541 * - it avoids deadlocks against smp_rendezvous() or, more
542 * generally, threads busy-waiting, with this spinlock held,
543 * and waiting for responses by threads on other CPUs
544 * (ie. smp_tlb_shootdown()).
546 * For the !SMP case it just needs to handle the former problem.
549 mtx_lock_spin(&smp_ipi_mtx);
554 /* cpu_boot(howto); */ /* doesn't do anything at the moment */
556 /* NOTREACHED */ /* assuming reset worked */
559 #if defined(WITNESS) || defined(INVARIANT_SUPPORT)
560 static int kassert_warn_only = 0;
562 static int kassert_do_kdb = 0;
565 static int kassert_do_ktr = 0;
567 static int kassert_do_log = 1;
568 static int kassert_log_pps_limit = 4;
569 static int kassert_log_mute_at = 0;
570 static int kassert_log_panic_at = 0;
571 static int kassert_warnings = 0;
573 SYSCTL_NODE(_debug, OID_AUTO, kassert, CTLFLAG_RW, NULL, "kassert options");
575 SYSCTL_INT(_debug_kassert, OID_AUTO, warn_only, CTLFLAG_RWTUN,
576 &kassert_warn_only, 0,
577 "KASSERT triggers a panic (1) or just a warning (0)");
580 SYSCTL_INT(_debug_kassert, OID_AUTO, do_kdb, CTLFLAG_RWTUN,
581 &kassert_do_kdb, 0, "KASSERT will enter the debugger");
585 SYSCTL_UINT(_debug_kassert, OID_AUTO, do_ktr, CTLFLAG_RWTUN,
587 "KASSERT does a KTR, set this to the KTRMASK you want");
590 SYSCTL_INT(_debug_kassert, OID_AUTO, do_log, CTLFLAG_RWTUN,
591 &kassert_do_log, 0, "KASSERT triggers a panic (1) or just a warning (0)");
593 SYSCTL_INT(_debug_kassert, OID_AUTO, warnings, CTLFLAG_RWTUN,
594 &kassert_warnings, 0, "number of KASSERTs that have been triggered");
596 SYSCTL_INT(_debug_kassert, OID_AUTO, log_panic_at, CTLFLAG_RWTUN,
597 &kassert_log_panic_at, 0, "max number of KASSERTS before we will panic");
599 SYSCTL_INT(_debug_kassert, OID_AUTO, log_pps_limit, CTLFLAG_RWTUN,
600 &kassert_log_pps_limit, 0, "limit number of log messages per second");
602 SYSCTL_INT(_debug_kassert, OID_AUTO, log_mute_at, CTLFLAG_RWTUN,
603 &kassert_log_mute_at, 0, "max number of KASSERTS to log");
605 static int kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS);
607 SYSCTL_PROC(_debug_kassert, OID_AUTO, kassert,
608 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_SECURE, NULL, 0,
609 kassert_sysctl_kassert, "I", "set to trigger a test kassert");
612 kassert_sysctl_kassert(SYSCTL_HANDLER_ARGS)
616 error = sysctl_wire_old_buffer(req, sizeof(int));
619 error = sysctl_handle_int(oidp, &i, 0, req);
621 if (error != 0 || req->newptr == NULL)
623 KASSERT(0, ("kassert_sysctl_kassert triggered kassert %d", i));
628 * Called by KASSERT, this decides if we will panic
629 * or if we will log via printf and/or ktr.
632 kassert_panic(const char *fmt, ...)
634 static char buf[256];
638 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
642 * panic if we're not just warning, or if we've exceeded
643 * kassert_log_panic_at warnings.
645 if (!kassert_warn_only ||
646 (kassert_log_panic_at > 0 &&
647 kassert_warnings >= kassert_log_panic_at)) {
657 * log if we've not yet met the mute limit.
659 if (kassert_do_log &&
660 (kassert_log_mute_at == 0 ||
661 kassert_warnings < kassert_log_mute_at)) {
662 static struct timeval lasterr;
665 if (ppsratecheck(&lasterr, &curerr, kassert_log_pps_limit)) {
666 printf("KASSERT failed: %s\n", buf);
671 if (kassert_do_kdb) {
672 kdb_enter(KDB_WHY_KASSERT, buf);
675 atomic_add_int(&kassert_warnings, 1);
680 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
681 * and then reboots. If we are called twice, then we avoid trying to sync
682 * the disks as this often leads to recursive panics.
685 panic(const char *fmt, ...)
694 vpanic(const char *fmt, va_list ap)
699 struct thread *td = curthread;
700 int bootopt, newpanic;
701 static char buf[256];
707 * stop_cpus_hard(other_cpus) should prevent multiple CPUs from
708 * concurrently entering panic. Only the winner will proceed
711 if (panicstr == NULL && !kdb_active) {
712 other_cpus = all_cpus;
713 CPU_CLR(PCPU_GET(cpuid), &other_cpus);
714 stop_cpus_hard(other_cpus);
718 * Ensure that the scheduler is stopped while panicking, even if panic
719 * has been entered from kdb.
721 td->td_stopsched = 1;
724 bootopt = RB_AUTOBOOT;
727 bootopt |= RB_NOSYNC;
735 (void)vsnprintf(buf, sizeof(buf), fmt, ap);
738 printf("panic: %s\n", buf);
745 printf("cpuid = %d\n", PCPU_GET(cpuid));
749 if (newpanic && trace_on_panic)
751 if (debugger_on_panic)
752 kdb_enter(KDB_WHY_PANIC, "panic");
754 /*thread_lock(td); */
755 td->td_flags |= TDF_INPANIC;
756 /* thread_unlock(td); */
758 bootopt |= RB_NOSYNC;
759 kern_reboot(bootopt);
763 * Support for poweroff delay.
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.
769 #ifndef POWEROFF_DELAY
770 # define POWEROFF_DELAY 5000
772 static int poweroff_delay = POWEROFF_DELAY;
774 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
775 &poweroff_delay, 0, "Delay before poweroff to write disk caches (msec)");
778 poweroff_wait(void *junk, int howto)
781 if (!(howto & RB_POWEROFF) || poweroff_delay <= 0)
783 DELAY(poweroff_delay * 1000);
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.
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");
798 kproc_shutdown(void *arg, int howto)
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);
811 if (error == EWOULDBLOCK)
812 printf("timed out\n");
818 kthread_shutdown(void *arg, int howto)
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);
831 if (error == EWOULDBLOCK)
832 printf("timed out\n");
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");
841 /* Registration of dumpers */
843 set_dumper(struct dumperinfo *di, const char *devname, struct thread *td)
848 error = priv_check(td, PRIV_SETDUMPER);
853 if (dumper.blockbuf != NULL)
854 free(dumper.blockbuf, M_DUMPER);
855 bzero(&dumper, sizeof(dumper));
856 dumpdevname[0] = '\0';
859 if (dumper.dumper != NULL)
862 wantcopy = strlcpy(dumpdevname, devname, sizeof(dumpdevname));
863 if (wantcopy >= sizeof(dumpdevname)) {
864 printf("set_dumper: device name truncated from '%s' -> '%s'\n",
865 devname, dumpdevname);
867 dumper.blockbuf = malloc(di->blocksize, M_DUMPER, M_WAITOK | M_ZERO);
871 /* Call dumper with bounds checking. */
873 dump_write(struct dumperinfo *di, void *virtual, vm_offset_t physical,
874 off_t offset, size_t length)
877 if (length != 0 && (offset < di->mediaoffset ||
878 offset - di->mediaoffset + length > di->mediasize)) {
879 printf("Attempt to write outside dump device boundaries.\n"
880 "offset(%jd), mediaoffset(%jd), length(%ju), mediasize(%jd).\n",
881 (intmax_t)offset, (intmax_t)di->mediaoffset,
882 (uintmax_t)length, (intmax_t)di->mediasize);
885 return (di->dumper(di->priv, virtual, physical, offset, length));
888 /* Call dumper with bounds checking. */
890 dump_write_pad(struct dumperinfo *di, void *virtual, vm_offset_t physical,
891 off_t offset, size_t length, size_t *size)
896 if (length > di->blocksize)
899 *size = di->blocksize;
900 if (length == di->blocksize)
904 memset(temp + length, 0, di->blocksize - length);
905 memcpy(temp, virtual, length);
907 ret = dump_write(di, temp, physical, offset, *size);
914 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
915 uint64_t dumplen, uint32_t blksz)
918 bzero(kdh, sizeof(*kdh));
919 strlcpy(kdh->magic, magic, sizeof(kdh->magic));
920 strlcpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
921 kdh->version = htod32(KERNELDUMPVERSION);
922 kdh->architectureversion = htod32(archver);
923 kdh->dumplength = htod64(dumplen);
924 kdh->dumptime = htod64(time_second);
925 kdh->blocksize = htod32(blksz);
926 strlcpy(kdh->hostname, prison0.pr_hostname, sizeof(kdh->hostname));
927 strlcpy(kdh->versionstring, version, sizeof(kdh->versionstring));
928 if (panicstr != NULL)
929 strlcpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
930 kdh->parity = kerneldump_parity(kdh);
934 DB_SHOW_COMMAND(panic, db_show_panic)
937 if (panicstr == NULL)
938 db_printf("panicstr not set\n");
940 db_printf("panic: %s\n", panicstr);