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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 $
43 #include "opt_ddb_trace.h"
44 #include "opt_panic.h"
45 #include "opt_show_busybufs.h"
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/eventhandler.h>
53 #include <sys/diskslice.h>
54 #include <sys/reboot.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/kerneldump.h>
62 #include <sys/kthread.h>
63 #include <sys/malloc.h>
64 #include <sys/mount.h>
65 #include <sys/queue.h>
66 #include <sys/sysctl.h>
67 #include <sys/vkernel.h>
69 #include <sys/sysproto.h>
70 #include <sys/device.h>
73 #include <sys/kern_syscall.h>
74 #include <vm/vm_map.h>
77 #include <sys/thread2.h>
79 #include <sys/mplock2.h>
81 #include <machine/cpu.h>
82 #include <machine/clock.h>
83 #include <machine/md_var.h>
84 #include <machine/smp.h> /* smp_active_mask, cpuid */
85 #include <machine/vmparam.h>
86 #include <machine/thread.h>
88 #include <sys/signalvar.h>
91 #include <dev/misc/gpio/gpio.h>
93 #ifndef PANIC_REBOOT_WAIT_TIME
94 #define PANIC_REBOOT_WAIT_TIME 15 /* default to 15 seconds */
98 * Note that stdarg.h and the ANSI style va_start macro is used for both
99 * ANSI and traditional C compilers. We use the machine version to stay
100 * within the confines of the kernel header files.
102 #include <machine/stdarg.h>
106 #ifdef DDB_UNATTENDED
107 int debugger_on_panic = 0;
109 int debugger_on_panic = 1;
111 SYSCTL_INT(_debug, OID_AUTO, debugger_on_panic, CTLFLAG_RW,
112 &debugger_on_panic, 0, "Run debugger on kernel panic");
115 int trace_on_panic = 1;
117 int trace_on_panic = 0;
119 SYSCTL_INT(_debug, OID_AUTO, trace_on_panic, CTLFLAG_RW,
120 &trace_on_panic, 0, "Print stack trace on kernel panic");
123 static int sync_on_panic = 0;
124 SYSCTL_INT(_kern, OID_AUTO, sync_on_panic, CTLFLAG_RW,
125 &sync_on_panic, 0, "Do a sync before rebooting from a panic");
127 SYSCTL_NODE(_kern, OID_AUTO, shutdown, CTLFLAG_RW, 0, "Shutdown environment");
130 * Variable panicstr contains argument to first call to panic; used as flag
131 * to indicate that the kernel has already called panic.
133 const char *panicstr;
135 int dumping; /* system is dumping */
136 static struct dumperinfo dumper; /* selected dumper */
138 globaldata_t panic_cpu_gd; /* which cpu took the panic */
139 struct lwkt_tokref panic_tokens[LWKT_MAXTOKENS];
140 int panic_tokens_count;
142 int bootverbose = 0; /* note: assignment to force non-bss */
143 SYSCTL_INT(_debug, OID_AUTO, bootverbose, CTLFLAG_RW,
144 &bootverbose, 0, "Verbose kernel messages");
146 int cold = 1; /* note: assignment to force non-bss */
147 int dumplo; /* OBSOLETE - savecore compat */
150 static void boot (int) __dead2;
151 static int setdumpdev (cdev_t dev);
152 static void poweroff_wait (void *, int);
153 static void print_uptime (void);
154 static void shutdown_halt (void *junk, int howto);
155 static void shutdown_panic (void *junk, int howto);
156 static void shutdown_reset (void *junk, int howto);
157 static int shutdown_busycount1(struct buf *bp, void *info);
158 static int shutdown_busycount2(struct buf *bp, void *info);
159 static void shutdown_cleanup_proc(struct proc *p);
161 /* register various local shutdown events */
163 shutdown_conf(void *unused)
165 EVENTHANDLER_REGISTER(shutdown_final, poweroff_wait, NULL, SHUTDOWN_PRI_FIRST);
166 EVENTHANDLER_REGISTER(shutdown_final, shutdown_halt, NULL, SHUTDOWN_PRI_LAST + 100);
167 EVENTHANDLER_REGISTER(shutdown_final, shutdown_panic, NULL, SHUTDOWN_PRI_LAST + 100);
168 EVENTHANDLER_REGISTER(shutdown_final, shutdown_reset, NULL, SHUTDOWN_PRI_LAST + 200);
171 SYSINIT(shutdown_conf, SI_BOOT2_MACHDEP, SI_ORDER_ANY, shutdown_conf, NULL)
176 * The system call that results in a reboot
181 sys_reboot(struct reboot_args *uap)
183 struct thread *td = curthread;
186 if ((error = priv_check(td, PRIV_REBOOT)))
196 * Called by events that want to shut down.. e.g <CTL><ALT><DEL> on a PC
198 static int shutdown_howto = 0;
201 shutdown_nice(int howto)
203 shutdown_howto = howto;
205 /* Send a signal to init(8) and have it shutdown the world */
206 if (initproc != NULL) {
207 ksignal(initproc, SIGINT);
209 /* No init(8) running, so simply reboot */
214 static int waittime = -1;
216 struct thread *dumpthread;
227 if (ts.tv_sec >= 86400) {
228 kprintf("%ldd", ts.tv_sec / 86400);
232 if (f || ts.tv_sec >= 3600) {
233 kprintf("%ldh", ts.tv_sec / 3600);
237 if (f || ts.tv_sec >= 60) {
238 kprintf("%ldm", ts.tv_sec / 60);
242 kprintf("%lds\n", ts.tv_sec);
246 * Go through the rigmarole of shutting down..
247 * this used to be in machdep.c but I'll be dammned if I could see
248 * anything machine dependant in it.
254 * Get rid of any user scheduler baggage and then give
255 * us a high priority.
257 if (curthread->td_release)
258 curthread->td_release(curthread);
259 lwkt_setpri_self(TDPRI_MAX);
261 /* collect extra flags that shutdown_nice might have set */
262 howto |= shutdown_howto;
266 * We really want to shutdown on the BSP. Subsystems such as ACPI
267 * can't power-down the box otherwise.
269 if (smp_active_mask > 1) {
270 kprintf("boot() called on cpu#%d\n", mycpu->gd_cpuid);
272 if (panicstr == NULL && mycpu->gd_cpuid != 0) {
273 kprintf("Switching to cpu #0 for shutdown\n");
274 lwkt_setcpu_self(globaldata_find(0));
278 * Do any callouts that should be done BEFORE syncing the filesystems.
280 EVENTHANDLER_INVOKE(shutdown_pre_sync, howto);
283 * Try to get rid of any remaining FS references. The calling
284 * process, proc0, and init may still hold references. The
285 * VFS cache subsystem may still hold a root reference to root.
287 * XXX this needs work. We really need to SIGSTOP all remaining
288 * processes in order to avoid blowups due to proc0's filesystem
289 * references going away. For now just make sure that the init
290 * process is stopped.
292 if (panicstr == NULL) {
293 shutdown_cleanup_proc(curproc);
294 shutdown_cleanup_proc(&proc0);
296 if (initproc != curproc) {
297 ksignal(initproc, SIGSTOP);
298 tsleep(boot, 0, "shutdn", hz / 20);
300 shutdown_cleanup_proc(initproc);
302 vfs_cache_setroot(NULL, NULL);
306 * Now sync filesystems
308 if (!cold && (howto & RB_NOSYNC) == 0 && waittime < 0) {
309 int iter, nbusy, pbusy;
312 kprintf("\nsyncing disks... ");
314 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */
317 * With soft updates, some buffers that are
318 * written will be remarked as dirty until other
319 * buffers are written.
321 for (iter = pbusy = 0; iter < 20; iter++) {
322 nbusy = scan_all_buffers(shutdown_busycount1, NULL);
325 kprintf("%d ", nbusy);
331 * Process soft update work queue if buffers don't sync
332 * after 6 iterations by permitting the syncer to run.
337 sys_sync(NULL); /* YYY was sync(&proc0, NULL). why proc0 ? */
338 tsleep(boot, 0, "shutdn", hz * iter / 20 + 1);
342 * Count only busy local buffers to prevent forcing
343 * a fsck if we're just a client of a wedged NFS server
345 nbusy = scan_all_buffers(shutdown_busycount2, NULL);
348 * Failed to sync all blocks. Indicate this and don't
349 * unmount filesystems (thus forcing an fsck on reboot).
351 kprintf("giving up on %d buffers\n", nbusy);
353 if (debugger_on_panic)
354 Debugger("busy buffer problem");
356 tsleep(boot, 0, "shutdn", hz * 5 + 1);
360 * Unmount filesystems
362 if (panicstr == NULL)
365 tsleep(boot, 0, "shutdn", hz / 10 + 1);
371 * Dump before doing post_sync shutdown ops
374 if ((howto & (RB_HALT|RB_DUMP)) == RB_DUMP && !cold) {
379 * Ok, now do things that assume all filesystem activity has
380 * been completed. This will also call the device shutdown
383 EVENTHANDLER_INVOKE(shutdown_post_sync, howto);
385 /* Now that we're going to really halt the system... */
386 EVENTHANDLER_INVOKE(shutdown_final, howto);
388 for(;;) ; /* safety against shutdown_reset not working */
393 * Pass 1 - Figure out if there are any busy or dirty buffers still present.
395 * We ignore TMPFS mounts in this pass.
398 shutdown_busycount1(struct buf *bp, void *info)
402 if ((vp = bp->b_vp) != NULL && vp->v_tag == VT_TMPFS)
404 if ((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp) > 0)
406 if ((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI)
412 * Pass 2 - only run after pass 1 has completed or has given up
414 * We ignore TMPFS, NFS, MFS, and SMBFS mounts in this pass.
417 shutdown_busycount2(struct buf *bp, void *info)
422 * Ignore tmpfs and nfs mounts
424 if ((vp = bp->b_vp) != NULL) {
425 if (vp->v_tag == VT_TMPFS)
427 if (vp->v_tag == VT_NFS)
429 if (vp->v_tag == VT_MFS)
431 if (vp->v_tag == VT_SMBFS)
436 * Only count buffers stuck on I/O, ignore everything else
438 if (((bp->b_flags & B_INVAL) == 0 && BUF_REFCNT(bp)) ||
439 ((bp->b_flags & (B_DELWRI|B_INVAL)) == B_DELWRI)) {
441 * Only count buffers undergoing write I/O
442 * on the related vnode.
444 if (bp->b_vp == NULL ||
445 bio_track_active(&bp->b_vp->v_track_write) == 0) {
448 #if defined(SHOW_BUSYBUFS) || defined(DIAGNOSTIC)
450 "%p dev:?, flags:%08x, loffset:%jd, doffset:%jd\n",
452 bp->b_flags, (intmax_t)bp->b_loffset,
453 (intmax_t)bp->b_bio2.bio_offset);
461 * If the shutdown was a clean halt, behave accordingly.
464 shutdown_halt(void *junk, int howto)
466 if (howto & RB_HALT) {
468 kprintf("The operating system has halted.\n");
469 #ifdef _KERNEL_VIRTUAL
472 kprintf("Please press any key to reboot.\n\n");
474 case -1: /* No console, just die */
486 * Check to see if the system paniced, pause and then reboot
487 * according to the specified delay.
490 shutdown_panic(void *junk, int howto)
494 if (howto & RB_DUMP) {
495 if (PANIC_REBOOT_WAIT_TIME != 0) {
496 if (PANIC_REBOOT_WAIT_TIME != -1) {
497 kprintf("Automatic reboot in %d seconds - "
498 "press a key on the console to abort\n",
499 PANIC_REBOOT_WAIT_TIME);
500 for (loop = PANIC_REBOOT_WAIT_TIME * 10;
502 DELAY(1000 * 100); /* 1/10th second */
503 /* Did user type a key? */
504 if (cncheckc() != -1)
510 } else { /* zero time specified - reboot NOW */
513 kprintf("--> Press a key on the console to reboot,\n");
514 kprintf("--> or switch off the system now.\n");
520 * Everything done, now reset
523 shutdown_reset(void *junk, int howto)
525 kprintf("Rebooting...\n");
526 DELAY(1000000); /* wait 1 sec for kprintf's to complete and be read */
527 /* cpu_boot(howto); */ /* doesn't do anything at the moment */
529 /* NOTREACHED */ /* assuming reset worked */
533 * Try to remove FS references in the specified process. This function
534 * is used during shutdown
538 shutdown_cleanup_proc(struct proc *p)
540 struct filedesc *fdp;
545 if ((fdp = p->p_fd) != NULL) {
548 cache_drop(&fdp->fd_ncdir);
553 cache_drop(&fdp->fd_nrdir);
558 cache_drop(&fdp->fd_njdir);
571 pmap_remove_pages(vmspace_pmap(vm),
573 VM_MAX_USER_ADDRESS);
574 vm_map_remove(&vm->vm_map,
576 VM_MAX_USER_ADDRESS);
581 * Magic number for savecore
583 * exported (symorder) and used at least by savecore(8)
585 * Mark it as used so that gcc doesn't optimize it away.
587 __attribute__((__used__))
588 static u_long const dumpmag = 0x8fca0101UL;
590 __attribute__((__used__))
591 static int dumpsize = 0; /* also for savecore */
593 static int dodump = 1;
595 SYSCTL_INT(_machdep, OID_AUTO, do_dump, CTLFLAG_RW, &dodump, 0,
596 "Try to perform coredump on kernel panic");
599 mkdumpheader(struct kerneldumpheader *kdh, char *magic, uint32_t archver,
600 uint64_t dumplen, uint32_t blksz)
602 bzero(kdh, sizeof(*kdh));
603 strncpy(kdh->magic, magic, sizeof(kdh->magic));
604 strncpy(kdh->architecture, MACHINE_ARCH, sizeof(kdh->architecture));
605 kdh->version = htod32(KERNELDUMPVERSION);
606 kdh->architectureversion = htod32(archver);
607 kdh->dumplength = htod64(dumplen);
608 kdh->dumptime = htod64(time_second);
609 kdh->blocksize = htod32(blksz);
610 strncpy(kdh->hostname, hostname, sizeof(kdh->hostname));
611 strncpy(kdh->versionstring, version, sizeof(kdh->versionstring));
612 if (panicstr != NULL)
613 strncpy(kdh->panicstring, panicstr, sizeof(kdh->panicstring));
614 kdh->parity = kerneldump_parity(kdh);
618 setdumpdev(cdev_t dev)
624 disk_dumpconf(NULL, 0/*off*/);
629 * We have to open the device before we can perform ioctls on it,
630 * or the slice/label data may not be present. Device opens are
631 * usually tracked by specfs, but the dump device can be set in
632 * early boot and may not be open so this is somewhat of a hack.
634 doopen = (dev->si_sysref.refcnt == 1);
636 error = dev_dopen(dev, FREAD, S_IFCHR, proc0.p_ucred);
640 error = disk_dumpconf(dev, 1/*on*/);
646 static void dump_conf (void *dummy);
648 dump_conf(void *dummy)
654 path = kmalloc(MNAMELEN, M_TEMP, M_WAITOK);
655 if (TUNABLE_STR_FETCH("dumpdev", path, MNAMELEN) != 0) {
657 * Make sure all disk devices created so far have also been
658 * probed, and also make sure that the newly created device
659 * nodes for probed disks are ready, too.
661 * XXX - Delay an additional 2 seconds to help drivers which
662 * pickup devices asynchronously and are not caught by
663 * CAM's initial probe.
666 tsleep(&_dummy, 0, "syncer", hz*2);
668 dev = kgetdiskbyname(path);
673 if (setdumpdev(dumpdev) != 0)
677 SYSINIT(dump_conf, SI_SUB_DUMP_CONF, SI_ORDER_FIRST, dump_conf, NULL)
680 sysctl_kern_dumpdev(SYSCTL_HANDLER_ARGS)
685 ndumpdev = dev2udev(dumpdev);
686 error = sysctl_handle_opaque(oidp, &ndumpdev, sizeof ndumpdev, req);
687 if (error == 0 && req->newptr != NULL)
688 error = setdumpdev(udev2dev(ndumpdev, 0));
692 SYSCTL_PROC(_kern, KERN_DUMPDEV, dumpdev, CTLTYPE_OPAQUE|CTLFLAG_RW,
693 0, sizeof dumpdev, sysctl_kern_dumpdev, "T,udev_t", "");
696 * Panic is called on unresolvable fatal errors. It prints "panic: mesg",
697 * and then reboots. If we are called twice, then we avoid trying to sync
698 * the disks as this often leads to recursive panics.
701 panic(const char *fmt, ...)
703 int bootopt, newpanic;
704 globaldata_t gd = mycpu;
705 thread_t td = gd->gd_curthread;
707 static char buf[256];
711 * If a panic occurs on multiple cpus before the first is able to
712 * halt the other cpus, only one cpu is allowed to take the panic.
713 * Attempt to be verbose about this situation but if the kprintf()
714 * itself panics don't let us overrun the kernel stack.
716 * Be very nasty about descheduling our thread at the lowest
717 * level possible in an attempt to freeze the thread without
718 * inducing further panics.
720 * Bumping gd_trap_nesting_level will also bypass assertions in
721 * lwkt_switch() and allow us to switch away even if we are a
722 * FAST interrupt or IPI.
724 * The setting of panic_cpu_gd also determines how kprintf()
725 * spin-locks itself. DDB can set panic_cpu_gd as well.
728 globaldata_t xgd = panic_cpu_gd;
731 * Someone else got the panic cpu
733 if (xgd && xgd != gd) {
735 ++mycpu->gd_trap_nesting_level;
736 if (mycpu->gd_trap_nesting_level < 25) {
737 kprintf("SECONDARY PANIC ON CPU %d THREAD %p\n",
738 mycpu->gd_cpuid, td);
740 td->td_release = NULL; /* be a grinch */
742 lwkt_deschedule_self(td);
746 /* --mycpu->gd_trap_nesting_level */
753 if (xgd && xgd == gd)
759 if (atomic_cmpset_ptr(&panic_cpu_gd, NULL, gd))
766 * Try to get the system into a working state. Save information
767 * we are about to destroy.
770 if (panicstr == NULL) {
771 bcopy(td->td_toks_array, panic_tokens, sizeof(panic_tokens));
772 panic_tokens_count = td->td_toks_stop - &td->td_toks_base;
774 lwkt_relalltokens(td);
775 td->td_toks_stop = &td->td_toks_base;
780 bootopt = RB_AUTOBOOT | RB_DUMP;
781 if (sync_on_panic == 0)
782 bootopt |= RB_NOSYNC;
785 bootopt |= RB_NOSYNC;
792 * Format the panic string.
795 kvsnprintf(buf, sizeof(buf), fmt, ap);
799 kprintf("panic: %s\n", buf);
801 /* two separate prints in case of an unmapped page and trap */
802 kprintf("cpuid = %d\n", mycpu->gd_cpuid);
805 #if (NGPIO > 0) && defined(ERROR_LED_ON_PANIC)
806 led_switch("error", 1);
809 #if defined(WDOG_DISABLE_ON_PANIC)
814 * Enter the debugger or fall through & dump. Entering the
815 * debugger will stop cpus. If not entering the debugger stop
819 if (newpanic && trace_on_panic)
821 if (debugger_on_panic)
827 stop_cpus(mycpu->gd_other_cpus);
835 * Support for poweroff delay.
837 #ifndef POWEROFF_DELAY
838 # define POWEROFF_DELAY 5000
840 static int poweroff_delay = POWEROFF_DELAY;
842 SYSCTL_INT(_kern_shutdown, OID_AUTO, poweroff_delay, CTLFLAG_RW,
843 &poweroff_delay, 0, "");
846 poweroff_wait(void *junk, int howto)
848 if(!(howto & RB_POWEROFF) || poweroff_delay <= 0)
850 DELAY(poweroff_delay * 1000);
854 * Some system processes (e.g. syncer) need to be stopped at appropriate
855 * points in their main loops prior to a system shutdown, so that they
856 * won't interfere with the shutdown process (e.g. by holding a disk buf
857 * to cause sync to fail). For each of these system processes, register
858 * shutdown_kproc() as a handler for one of shutdown events.
860 static int kproc_shutdown_wait = 60;
861 SYSCTL_INT(_kern_shutdown, OID_AUTO, kproc_shutdown_wait, CTLFLAG_RW,
862 &kproc_shutdown_wait, 0, "");
865 shutdown_kproc(void *arg, int howto)
874 td = (struct thread *)arg;
875 if ((p = td->td_proc) != NULL) {
876 kprintf("Waiting (max %d seconds) for system process `%s' to stop...",
877 kproc_shutdown_wait, p->p_comm);
879 kprintf("Waiting (max %d seconds) for system thread %s to stop...",
880 kproc_shutdown_wait, td->td_comm);
882 error = suspend_kproc(td, kproc_shutdown_wait * hz);
884 if (error == EWOULDBLOCK)
885 kprintf("timed out\n");
887 kprintf("stopped\n");
890 /* Registration of dumpers */
892 set_dumper(struct dumperinfo *di)
895 bzero(&dumper, sizeof(dumper));
899 if (dumper.dumper != NULL)
909 #if defined (_KERNEL_VIRTUAL)
910 /* VKERNELs don't support dumps */
911 kprintf("VKERNEL doesn't support dumps\n");
915 * If there is a dumper registered and we aren't dumping already, call
916 * the machine dependent dumpsys (md_dumpsys) to do the hard work.
918 * XXX: while right now the md_dumpsys() of x86 and x86_64 could be
919 * factored out completely into here, I rather keep them machine
920 * dependent in case we ever add a platform which does not share
921 * the same dumpsys() code, such as arm.
923 if (dumper.dumper != NULL && !dumping) {
929 int dump_stop_usertds = 0;
934 need_user_resched_remote(void *dummy)
941 dump_reactivate_cpus(void)
948 dump_stop_usertds = 1;
953 for (cpu = 0; cpu < ncpus; cpu++) {
954 gd = globaldata_find(cpu);
955 seq = lwkt_send_ipiq(gd, need_user_resched_remote, NULL);
956 lwkt_wait_ipiq(gd, seq);
959 restart_cpus(stopped_cpus);