The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/kern/subr_kdb.c

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    1 /*-
    2  * Copyright (c) 2004 The FreeBSD Project
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms, with or without
    6  * modification, are permitted provided that the following conditions
    7  * are met:
    8  *
    9  * 1. Redistributions of source code must retain the above copyright
   10  *    notice, this list of conditions and the following disclaimer.
   11  * 2. Redistributions in binary form must reproduce the above copyright
   12  *    notice, this list of conditions and the following disclaimer in the
   13  *    documentation and/or other materials provided with the distribution.
   14  *
   15  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
   16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   18  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   25  */
   26 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD$");
   29 
   30 #include "opt_kdb.h"
   31 #include "opt_stack.h"
   32 
   33 #include <sys/param.h>
   34 #include <sys/systm.h>
   35 #include <sys/kdb.h>
   36 #include <sys/kernel.h>
   37 #include <sys/malloc.h>
   38 #include <sys/pcpu.h>
   39 #include <sys/proc.h>
   40 #include <sys/smp.h>
   41 #include <sys/stack.h>
   42 #include <sys/sysctl.h>
   43 
   44 #include <machine/kdb.h>
   45 #include <machine/pcb.h>
   46 
   47 #ifdef SMP
   48 #include <machine/smp.h>
   49 #endif
   50 
   51 int kdb_active = 0;
   52 static void *kdb_jmpbufp = NULL;
   53 struct kdb_dbbe *kdb_dbbe = NULL;
   54 static struct pcb kdb_pcb;
   55 struct pcb *kdb_thrctx = NULL;
   56 struct thread *kdb_thread = NULL;
   57 struct trapframe *kdb_frame = NULL;
   58 
   59 #ifdef BREAK_TO_DEBUGGER
   60 #define KDB_BREAK_TO_DEBUGGER   1
   61 #else
   62 #define KDB_BREAK_TO_DEBUGGER   0
   63 #endif
   64 
   65 #ifdef ALT_BREAK_TO_DEBUGGER
   66 #define KDB_ALT_BREAK_TO_DEBUGGER       1
   67 #else
   68 #define KDB_ALT_BREAK_TO_DEBUGGER       0
   69 #endif
   70 
   71 static int      kdb_break_to_debugger = KDB_BREAK_TO_DEBUGGER;
   72 static int      kdb_alt_break_to_debugger = KDB_ALT_BREAK_TO_DEBUGGER;
   73 
   74 KDB_BACKEND(null, NULL, NULL, NULL, NULL);
   75 SET_DECLARE(kdb_dbbe_set, struct kdb_dbbe);
   76 
   77 static int kdb_sysctl_available(SYSCTL_HANDLER_ARGS);
   78 static int kdb_sysctl_current(SYSCTL_HANDLER_ARGS);
   79 static int kdb_sysctl_enter(SYSCTL_HANDLER_ARGS);
   80 static int kdb_sysctl_panic(SYSCTL_HANDLER_ARGS);
   81 static int kdb_sysctl_trap(SYSCTL_HANDLER_ARGS);
   82 static int kdb_sysctl_trap_code(SYSCTL_HANDLER_ARGS);
   83 
   84 SYSCTL_NODE(_debug, OID_AUTO, kdb, CTLFLAG_RW, NULL, "KDB nodes");
   85 
   86 SYSCTL_PROC(_debug_kdb, OID_AUTO, available, CTLTYPE_STRING | CTLFLAG_RD, NULL,
   87     0, kdb_sysctl_available, "A", "list of available KDB backends");
   88 
   89 SYSCTL_PROC(_debug_kdb, OID_AUTO, current, CTLTYPE_STRING | CTLFLAG_RW, NULL,
   90     0, kdb_sysctl_current, "A", "currently selected KDB backend");
   91 
   92 SYSCTL_PROC(_debug_kdb, OID_AUTO, enter, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
   93     kdb_sysctl_enter, "I", "set to enter the debugger");
   94 
   95 SYSCTL_PROC(_debug_kdb, OID_AUTO, panic, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
   96     kdb_sysctl_panic, "I", "set to panic the kernel");
   97 
   98 SYSCTL_PROC(_debug_kdb, OID_AUTO, trap, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
   99     kdb_sysctl_trap, "I", "set to cause a page fault via data access");
  100 
  101 SYSCTL_PROC(_debug_kdb, OID_AUTO, trap_code, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
  102     kdb_sysctl_trap_code, "I", "set to cause a page fault via code access");
  103 
  104 SYSCTL_INT(_debug_kdb, OID_AUTO, break_to_debugger, CTLTYPE_INT | CTLFLAG_RW |
  105     CTLFLAG_TUN, &kdb_break_to_debugger, 0, "Enable break to debugger");
  106 TUNABLE_INT("debug.kdb.break_to_debugger", &kdb_break_to_debugger);
  107 
  108 SYSCTL_INT(_debug_kdb, OID_AUTO, alt_break_to_debugger, CTLTYPE_INT |
  109     CTLFLAG_RW | CTLFLAG_TUN, &kdb_alt_break_to_debugger, 0,
  110     "Enable alternative break to debugger");
  111 TUNABLE_INT("debug.kdb.alt_break_to_debugger", &kdb_alt_break_to_debugger);
  112 
  113 /*
  114  * Flag indicating whether or not to IPI the other CPUs to stop them on
  115  * entering the debugger.  Sometimes, this will result in a deadlock as
  116  * stop_cpus() waits for the other cpus to stop, so we allow it to be
  117  * disabled.  In order to maximize the chances of success, use a hard
  118  * stop for that.
  119  */
  120 #ifdef SMP
  121 static int kdb_stop_cpus = 1;
  122 SYSCTL_INT(_debug_kdb, OID_AUTO, stop_cpus, CTLFLAG_RW | CTLFLAG_TUN,
  123     &kdb_stop_cpus, 0, "stop other CPUs when entering the debugger");
  124 TUNABLE_INT("debug.kdb.stop_cpus", &kdb_stop_cpus);
  125 #endif
  126 
  127 /*
  128  * Flag to indicate to debuggers why the debugger was entered.
  129  */
  130 const char * volatile kdb_why = KDB_WHY_UNSET;
  131 
  132 static int
  133 kdb_sysctl_available(SYSCTL_HANDLER_ARGS)
  134 {
  135         struct kdb_dbbe *be, **iter;
  136         char *avail, *p;
  137         ssize_t len, sz;
  138         int error;
  139 
  140         sz = 0;
  141         SET_FOREACH(iter, kdb_dbbe_set) {
  142                 be = *iter;
  143                 if (be->dbbe_active == 0)
  144                         sz += strlen(be->dbbe_name) + 1;
  145         }
  146         sz++;
  147         avail = malloc(sz, M_TEMP, M_WAITOK);
  148         p = avail;
  149         *p = '\0';
  150 
  151         SET_FOREACH(iter, kdb_dbbe_set) {
  152                 be = *iter;
  153                 if (be->dbbe_active == 0) {
  154                         len = snprintf(p, sz, "%s ", be->dbbe_name);
  155                         p += len;
  156                         sz -= len;
  157                 }
  158         }
  159         KASSERT(sz >= 0, ("%s", __func__));
  160         error = sysctl_handle_string(oidp, avail, 0, req);
  161         free(avail, M_TEMP);
  162         return (error);
  163 }
  164 
  165 static int
  166 kdb_sysctl_current(SYSCTL_HANDLER_ARGS)
  167 {
  168         char buf[16];
  169         int error;
  170 
  171         if (kdb_dbbe != NULL)
  172                 strlcpy(buf, kdb_dbbe->dbbe_name, sizeof(buf));
  173         else
  174                 *buf = '\0';
  175         error = sysctl_handle_string(oidp, buf, sizeof(buf), req);
  176         if (error != 0 || req->newptr == NULL)
  177                 return (error);
  178         if (kdb_active)
  179                 return (EBUSY);
  180         return (kdb_dbbe_select(buf));
  181 }
  182 
  183 static int
  184 kdb_sysctl_enter(SYSCTL_HANDLER_ARGS)
  185 {
  186         int error, i;
  187 
  188         error = sysctl_wire_old_buffer(req, sizeof(int));
  189         if (error == 0) {
  190                 i = 0;
  191                 error = sysctl_handle_int(oidp, &i, 0, req);
  192         }
  193         if (error != 0 || req->newptr == NULL)
  194                 return (error);
  195         if (kdb_active)
  196                 return (EBUSY);
  197         kdb_enter(KDB_WHY_SYSCTL, "sysctl debug.kdb.enter");
  198         return (0);
  199 }
  200 
  201 static int
  202 kdb_sysctl_panic(SYSCTL_HANDLER_ARGS)
  203 {
  204         int error, i;
  205 
  206         error = sysctl_wire_old_buffer(req, sizeof(int));
  207         if (error == 0) {
  208                 i = 0;
  209                 error = sysctl_handle_int(oidp, &i, 0, req);
  210         }
  211         if (error != 0 || req->newptr == NULL)
  212                 return (error);
  213         panic("kdb_sysctl_panic");
  214         return (0);
  215 }
  216 
  217 static int
  218 kdb_sysctl_trap(SYSCTL_HANDLER_ARGS)
  219 {
  220         int error, i;
  221         int *addr = (int *)0x10;
  222 
  223         error = sysctl_wire_old_buffer(req, sizeof(int));
  224         if (error == 0) {
  225                 i = 0;
  226                 error = sysctl_handle_int(oidp, &i, 0, req);
  227         }
  228         if (error != 0 || req->newptr == NULL)
  229                 return (error);
  230         return (*addr);
  231 }
  232 
  233 static int
  234 kdb_sysctl_trap_code(SYSCTL_HANDLER_ARGS)
  235 {
  236         int error, i;
  237         void (*fp)(u_int, u_int, u_int) = (void *)0xdeadc0de;
  238 
  239         error = sysctl_wire_old_buffer(req, sizeof(int));
  240         if (error == 0) {
  241                 i = 0;
  242                 error = sysctl_handle_int(oidp, &i, 0, req);
  243         }
  244         if (error != 0 || req->newptr == NULL)
  245                 return (error);
  246         (*fp)(0x11111111, 0x22222222, 0x33333333);
  247         return (0);
  248 }
  249 
  250 void
  251 kdb_panic(const char *msg)
  252 {
  253 
  254         printf("KDB: panic\n");
  255         panic("%s", msg);
  256 }
  257 
  258 void
  259 kdb_reboot(void)
  260 {
  261 
  262         printf("KDB: reboot requested\n");
  263         shutdown_nice(0);
  264 }
  265 
  266 /*
  267  * Solaris implements a new BREAK which is initiated by a character sequence
  268  * CR ~ ^b which is similar to a familiar pattern used on Sun servers by the
  269  * Remote Console.
  270  *
  271  * Note that this function may be called from almost anywhere, with interrupts
  272  * disabled and with unknown locks held, so it must not access data other than
  273  * its arguments.  Its up to the caller to ensure that the state variable is
  274  * consistent.
  275  */
  276 
  277 #define KEY_CR          13      /* CR '\r' */
  278 #define KEY_TILDE       126     /* ~ */
  279 #define KEY_CRTLB       2       /* ^B */
  280 #define KEY_CRTLP       16      /* ^P */
  281 #define KEY_CRTLR       18      /* ^R */
  282 
  283 int
  284 kdb_break(void)
  285 {
  286 
  287         if (!kdb_break_to_debugger)
  288                 return (0);
  289         kdb_enter(KDB_WHY_BREAK, "Break to debugger");
  290         return (KDB_REQ_DEBUGGER);
  291 }
  292 
  293 static int
  294 kdb_alt_break_state(int key, int *state)
  295 {
  296         int brk;
  297 
  298         brk = 0;
  299         switch (*state) {
  300         case 0:
  301                 if (key == KEY_CR)
  302                         *state = 1;
  303                 break;
  304         case 1:
  305                 if (key == KEY_TILDE)
  306                         *state = 2;
  307                 break;
  308         case 2:
  309                 if (key == KEY_CRTLB)
  310                         brk = KDB_REQ_DEBUGGER;
  311                 else if (key == KEY_CRTLP)
  312                         brk = KDB_REQ_PANIC;
  313                 else if (key == KEY_CRTLR)
  314                         brk = KDB_REQ_REBOOT;
  315                 *state = 0;
  316         }
  317         return (brk);
  318 }
  319 
  320 static int
  321 kdb_alt_break_internal(int key, int *state, int force_gdb)
  322 {
  323         int brk;
  324 
  325         if (!kdb_alt_break_to_debugger)
  326                 return (0);
  327         brk = kdb_alt_break_state(key, state);
  328         switch (brk) {
  329         case KDB_REQ_DEBUGGER:
  330                 if (force_gdb)
  331                         kdb_dbbe_select("gdb");
  332                 kdb_enter(KDB_WHY_BREAK, "Break to debugger");
  333                 break;
  334 
  335         case KDB_REQ_PANIC:
  336                 if (force_gdb)
  337                         kdb_dbbe_select("gdb");
  338                 kdb_panic("Panic sequence on console");
  339                 break;
  340 
  341         case KDB_REQ_REBOOT:
  342                 kdb_reboot();
  343                 break;
  344         }
  345         return (0);
  346 }
  347 
  348 int
  349 kdb_alt_break(int key, int *state)
  350 {
  351 
  352         return (kdb_alt_break_internal(key, state, 0));
  353 }
  354 
  355 /*
  356  * This variation on kdb_alt_break() is used only by dcons, which has its own
  357  * configuration flag to force GDB use regardless of the global KDB
  358  * configuration.
  359  */
  360 int
  361 kdb_alt_break_gdb(int key, int *state)
  362 {
  363 
  364         return (kdb_alt_break_internal(key, state, 1));
  365 }
  366 
  367 /*
  368  * Print a backtrace of the calling thread. The backtrace is generated by
  369  * the selected debugger, provided it supports backtraces. If no debugger
  370  * is selected or the current debugger does not support backtraces, this
  371  * function silently returns.
  372  */
  373 
  374 void
  375 kdb_backtrace(void)
  376 {
  377 
  378         if (kdb_dbbe != NULL && kdb_dbbe->dbbe_trace != NULL) {
  379                 printf("KDB: stack backtrace:\n");
  380                 kdb_dbbe->dbbe_trace();
  381         }
  382 #ifdef STACK
  383         else {
  384                 struct stack st;
  385 
  386                 printf("KDB: stack backtrace:\n");
  387                 stack_zero(&st);
  388                 stack_save(&st);
  389                 stack_print_ddb(&st);
  390         }
  391 #endif
  392 }
  393 
  394 /*
  395  * Similar to kdb_backtrace() except that it prints a backtrace of an
  396  * arbitrary thread rather than the calling thread.
  397  */
  398 void
  399 kdb_backtrace_thread(struct thread *td)
  400 {
  401 
  402         if (kdb_dbbe != NULL && kdb_dbbe->dbbe_trace_thread != NULL) {
  403                 printf("KDB: stack backtrace of thread %d:\n", td->td_tid);
  404                 kdb_dbbe->dbbe_trace_thread(td);
  405         }
  406 #ifdef STACK
  407         else {
  408                 struct stack st;
  409 
  410                 printf("KDB: stack backtrace of thread %d:\n", td->td_tid);
  411                 stack_zero(&st);
  412                 stack_save_td(&st, td);
  413                 stack_print_ddb(&st);
  414         }
  415 #endif
  416 }
  417 
  418 /*
  419  * Set/change the current backend.
  420  */
  421 
  422 int
  423 kdb_dbbe_select(const char *name)
  424 {
  425         struct kdb_dbbe *be, **iter;
  426 
  427         SET_FOREACH(iter, kdb_dbbe_set) {
  428                 be = *iter;
  429                 if (be->dbbe_active == 0 && strcmp(be->dbbe_name, name) == 0) {
  430                         kdb_dbbe = be;
  431                         return (0);
  432                 }
  433         }
  434         return (EINVAL);
  435 }
  436 
  437 /*
  438  * Enter the currently selected debugger. If a message has been provided,
  439  * it is printed first. If the debugger does not support the enter method,
  440  * it is entered by using breakpoint(), which enters the debugger through
  441  * kdb_trap().  The 'why' argument will contain a more mechanically usable
  442  * string than 'msg', and is relied upon by DDB scripting to identify the
  443  * reason for entering the debugger so that the right script can be run.
  444  */
  445 void
  446 kdb_enter(const char *why, const char *msg)
  447 {
  448 
  449         if (kdb_dbbe != NULL && kdb_active == 0) {
  450                 if (msg != NULL)
  451                         printf("KDB: enter: %s\n", msg);
  452                 kdb_why = why;
  453                 breakpoint();
  454                 kdb_why = KDB_WHY_UNSET;
  455         }
  456 }
  457 
  458 /*
  459  * Initialize the kernel debugger interface.
  460  */
  461 
  462 void
  463 kdb_init(void)
  464 {
  465         struct kdb_dbbe *be, **iter;
  466         int cur_pri, pri;
  467 
  468         kdb_active = 0;
  469         kdb_dbbe = NULL;
  470         cur_pri = -1;
  471         SET_FOREACH(iter, kdb_dbbe_set) {
  472                 be = *iter;
  473                 pri = (be->dbbe_init != NULL) ? be->dbbe_init() : -1;
  474                 be->dbbe_active = (pri >= 0) ? 0 : -1;
  475                 if (pri > cur_pri) {
  476                         cur_pri = pri;
  477                         kdb_dbbe = be;
  478                 }
  479         }
  480         if (kdb_dbbe != NULL) {
  481                 printf("KDB: debugger backends:");
  482                 SET_FOREACH(iter, kdb_dbbe_set) {
  483                         be = *iter;
  484                         if (be->dbbe_active == 0)
  485                                 printf(" %s", be->dbbe_name);
  486                 }
  487                 printf("\n");
  488                 printf("KDB: current backend: %s\n",
  489                     kdb_dbbe->dbbe_name);
  490         }
  491 }
  492 
  493 /*
  494  * Handle contexts.
  495  */
  496 
  497 void *
  498 kdb_jmpbuf(jmp_buf new)
  499 {
  500         void *old;
  501 
  502         old = kdb_jmpbufp;
  503         kdb_jmpbufp = new;
  504         return (old);
  505 }
  506 
  507 void
  508 kdb_reenter(void)
  509 {
  510 
  511         if (!kdb_active || kdb_jmpbufp == NULL)
  512                 return;
  513 
  514         longjmp(kdb_jmpbufp, 1);
  515         /* NOTREACHED */
  516 }
  517 
  518 /*
  519  * Thread related support functions.
  520  */
  521 
  522 struct pcb *
  523 kdb_thr_ctx(struct thread *thr)
  524 {  
  525 #if defined(SMP) && defined(KDB_STOPPEDPCB)
  526         struct pcpu *pc;
  527 #endif
  528  
  529         if (thr == curthread) 
  530                 return (&kdb_pcb);
  531 
  532 #if defined(SMP) && defined(KDB_STOPPEDPCB)
  533         SLIST_FOREACH(pc, &cpuhead, pc_allcpu)  {
  534                 if (pc->pc_curthread == thr && (stopped_cpus & pc->pc_cpumask))
  535                         return (KDB_STOPPEDPCB(pc));
  536         }
  537 #endif
  538         return (thr->td_pcb);
  539 }
  540 
  541 struct thread *
  542 kdb_thr_first(void)
  543 {
  544         struct proc *p;
  545         struct thread *thr;
  546 
  547         p = LIST_FIRST(&allproc);
  548         while (p != NULL) {
  549                 if (p->p_flag & P_INMEM) {
  550                         thr = FIRST_THREAD_IN_PROC(p);
  551                         if (thr != NULL)
  552                                 return (thr);
  553                 }
  554                 p = LIST_NEXT(p, p_list);
  555         }
  556         return (NULL);
  557 }
  558 
  559 struct thread *
  560 kdb_thr_from_pid(pid_t pid)
  561 {
  562         struct proc *p;
  563 
  564         p = LIST_FIRST(&allproc);
  565         while (p != NULL) {
  566                 if (p->p_flag & P_INMEM && p->p_pid == pid)
  567                         return (FIRST_THREAD_IN_PROC(p));
  568                 p = LIST_NEXT(p, p_list);
  569         }
  570         return (NULL);
  571 }
  572 
  573 struct thread *
  574 kdb_thr_lookup(lwpid_t tid)
  575 {
  576         struct thread *thr;
  577 
  578         thr = kdb_thr_first();
  579         while (thr != NULL && thr->td_tid != tid)
  580                 thr = kdb_thr_next(thr);
  581         return (thr);
  582 }
  583 
  584 struct thread *
  585 kdb_thr_next(struct thread *thr)
  586 {
  587         struct proc *p;
  588 
  589         p = thr->td_proc;
  590         thr = TAILQ_NEXT(thr, td_plist);
  591         do {
  592                 if (thr != NULL)
  593                         return (thr);
  594                 p = LIST_NEXT(p, p_list);
  595                 if (p != NULL && (p->p_flag & P_INMEM))
  596                         thr = FIRST_THREAD_IN_PROC(p);
  597         } while (p != NULL);
  598         return (NULL);
  599 }
  600 
  601 int
  602 kdb_thr_select(struct thread *thr)
  603 {
  604         if (thr == NULL)
  605                 return (EINVAL);
  606         kdb_thread = thr;
  607         kdb_thrctx = kdb_thr_ctx(thr);
  608         return (0);
  609 }
  610 
  611 /*
  612  * Enter the debugger due to a trap.
  613  */
  614 
  615 int
  616 kdb_trap(int type, int code, struct trapframe *tf)
  617 {
  618         struct kdb_dbbe *be;
  619         register_t intr;
  620 #ifdef SMP
  621         int did_stop_cpus;
  622 #endif
  623         int handled;
  624 
  625         be = kdb_dbbe;
  626         if (be == NULL || be->dbbe_trap == NULL)
  627                 return (0);
  628 
  629         /* We reenter the debugger through kdb_reenter(). */
  630         if (kdb_active)
  631                 return (0);
  632 
  633         intr = intr_disable();
  634 
  635 #ifdef SMP
  636         if (!SCHEDULER_STOPPED()) {
  637                 if ((did_stop_cpus = kdb_stop_cpus) != 0)
  638                         stop_cpus_hard(PCPU_GET(other_cpus));
  639         } else
  640                 did_stop_cpus = 0;
  641 #endif
  642 
  643         kdb_active++;
  644 
  645         kdb_frame = tf;
  646 
  647         /* Let MD code do its thing first... */
  648         kdb_cpu_trap(type, code);
  649 
  650         makectx(tf, &kdb_pcb);
  651         kdb_thr_select(curthread);
  652 
  653         for (;;) {
  654                 handled = be->dbbe_trap(type, code);
  655                 if (be == kdb_dbbe)
  656                         break;
  657                 be = kdb_dbbe;
  658                 if (be == NULL || be->dbbe_trap == NULL)
  659                         break;
  660                 printf("Switching to %s back-end\n", be->dbbe_name);
  661         }
  662 
  663         kdb_active--;
  664 
  665 #ifdef SMP
  666         if (did_stop_cpus)
  667                 restart_cpus(stopped_cpus);
  668 #endif
  669 
  670         intr_restore(intr);
  671 
  672         return (handled);
  673 }

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