2 * SPDX-License-Identifier: MIT-CMU
4 * Mach Operating System
5 * Copyright (c) 1991,1990 Carnegie Mellon University
8 * Permission to use, copy, modify and distribute this software and its
9 * documentation is hereby granted, provided that both the copyright
10 * notice and this permission notice appear in all copies of the
11 * software, derivative works or modified versions, and any portions
12 * thereof, and that both notices appear in supporting documentation.
14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 * Carnegie Mellon requests users of this software to return to
20 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
21 * School of Computer Science
22 * Carnegie Mellon University
23 * Pittsburgh PA 15213-3890
25 * any improvements or extensions that they make and grant Carnegie the
26 * rights to redistribute these changes.
29 * Author: David B. Golub, Carnegie Mellon University
36 #include <sys/cdefs.h>
37 __FBSDID("$FreeBSD$");
39 #include <sys/param.h>
40 #include <sys/linker_set.h>
43 #include <sys/mutex.h>
45 #include <sys/reboot.h>
46 #include <sys/signalvar.h>
47 #include <sys/systm.h>
50 #include <sys/watchdog.h>
51 #include <sys/kernel.h>
54 #include <ddb/db_command.h>
55 #include <ddb/db_lex.h>
56 #include <ddb/db_output.h>
58 #include <machine/cpu.h>
59 #include <machine/setjmp.h>
62 * Exported global variables
66 db_addr_t db_last_addr;
70 static db_cmdfcn_t db_dump;
71 static db_cmdfcn_t db_fncall;
72 static db_cmdfcn_t db_gdb;
73 static db_cmdfcn_t db_halt;
74 static db_cmdfcn_t db_kill;
75 static db_cmdfcn_t db_reset;
76 static db_cmdfcn_t db_stack_trace;
77 static db_cmdfcn_t db_stack_trace_active;
78 static db_cmdfcn_t db_stack_trace_all;
79 static db_cmdfcn_t db_watchdog;
85 static struct command db_show_active_cmds[] = {
86 { "trace", db_stack_trace_active, 0, NULL },
88 struct command_table db_show_active_table =
89 LIST_HEAD_INITIALIZER(db_show_active_table);
91 static struct command db_show_all_cmds[] = {
92 { "trace", db_stack_trace_all, 0, NULL },
94 struct command_table db_show_all_table =
95 LIST_HEAD_INITIALIZER(db_show_all_table);
97 static struct command db_show_cmds[] = {
98 { "active", 0, 0, &db_show_active_table },
99 { "all", 0, 0, &db_show_all_table },
100 { "registers", db_show_regs, 0, NULL },
101 { "breaks", db_listbreak_cmd, 0, NULL },
102 { "threads", db_show_threads, 0, NULL },
104 struct command_table db_show_table = LIST_HEAD_INITIALIZER(db_show_table);
106 static struct command db_cmds[] = {
107 { "print", db_print_cmd, 0, NULL },
108 { "p", db_print_cmd, 0, NULL },
109 { "examine", db_examine_cmd, CS_SET_DOT, NULL },
110 { "x", db_examine_cmd, CS_SET_DOT, NULL },
111 { "search", db_search_cmd, CS_OWN|CS_SET_DOT, NULL },
112 { "set", db_set_cmd, CS_OWN, NULL },
113 { "write", db_write_cmd, CS_MORE|CS_SET_DOT, NULL },
114 { "w", db_write_cmd, CS_MORE|CS_SET_DOT, NULL },
115 { "delete", db_delete_cmd, 0, NULL },
116 { "d", db_delete_cmd, 0, NULL },
117 { "dump", db_dump, 0, NULL },
118 { "break", db_breakpoint_cmd, 0, NULL },
119 { "b", db_breakpoint_cmd, 0, NULL },
120 { "dwatch", db_deletewatch_cmd, 0, NULL },
121 { "watch", db_watchpoint_cmd, CS_MORE,NULL },
122 { "dhwatch", db_deletehwatch_cmd, 0, NULL },
123 { "hwatch", db_hwatchpoint_cmd, 0, NULL },
124 { "step", db_single_step_cmd, 0, NULL },
125 { "s", db_single_step_cmd, 0, NULL },
126 { "continue", db_continue_cmd, 0, NULL },
127 { "c", db_continue_cmd, 0, NULL },
128 { "until", db_trace_until_call_cmd,0, NULL },
129 { "next", db_trace_until_matching_cmd,0, NULL },
130 { "match", db_trace_until_matching_cmd,0, NULL },
131 { "trace", db_stack_trace, CS_OWN, NULL },
132 { "t", db_stack_trace, CS_OWN, NULL },
133 /* XXX alias for active trace */
134 { "acttrace", db_stack_trace_active, 0, NULL },
135 /* XXX alias for all trace */
136 { "alltrace", db_stack_trace_all, 0, NULL },
137 { "where", db_stack_trace, CS_OWN, NULL },
138 { "bt", db_stack_trace, CS_OWN, NULL },
139 { "call", db_fncall, CS_OWN, NULL },
140 { "show", 0, 0, &db_show_table },
141 { "ps", db_ps, 0, NULL },
142 { "gdb", db_gdb, 0, NULL },
143 { "halt", db_halt, 0, NULL },
144 { "reboot", db_reset, 0, NULL },
145 { "reset", db_reset, 0, NULL },
146 { "kill", db_kill, CS_OWN, NULL },
147 { "watchdog", db_watchdog, CS_OWN, NULL },
148 { "thread", db_set_thread, CS_OWN, NULL },
149 { "run", db_run_cmd, CS_OWN, NULL },
150 { "script", db_script_cmd, CS_OWN, NULL },
151 { "scripts", db_scripts_cmd, 0, NULL },
152 { "unscript", db_unscript_cmd, CS_OWN, NULL },
153 { "capture", db_capture_cmd, CS_OWN, NULL },
154 { "textdump", db_textdump_cmd, CS_OWN, NULL },
155 { "findstack", db_findstack_cmd, 0, NULL },
157 struct command_table db_cmd_table = LIST_HEAD_INITIALIZER(db_cmd_table);
159 static struct command *db_last_command = NULL;
162 * if 'ed' style: 'dot' is set at start of last item printed,
163 * and '+' points to next line.
164 * Otherwise: 'dot' points to next item, '..' points to last.
166 static bool db_ed_style = true;
169 * Utility routine - discard tokens through end-of-line.
181 * Results of command search.
186 #define CMD_AMBIGUOUS 3
189 static void db_cmd_match(char *name, struct command *cmd,
190 struct command **cmdp, int *resultp);
191 static void db_cmd_list(struct command_table *table);
192 static int db_cmd_search(char *name, struct command_table *table,
193 struct command **cmdp);
194 static void db_command(struct command **last_cmdp,
195 struct command_table *cmd_table, int dopager);
198 * Initialize the command lists from the static tables.
201 db_command_init(void)
203 #define N(a) (sizeof(a) / sizeof(a[0]))
206 for (i = 0; i < N(db_cmds); i++)
207 db_command_register(&db_cmd_table, &db_cmds[i]);
208 for (i = 0; i < N(db_show_cmds); i++)
209 db_command_register(&db_show_table, &db_show_cmds[i]);
210 for (i = 0; i < N(db_show_active_cmds); i++)
211 db_command_register(&db_show_active_table,
212 &db_show_active_cmds[i]);
213 for (i = 0; i < N(db_show_all_cmds); i++)
214 db_command_register(&db_show_all_table, &db_show_all_cmds[i]);
219 * Register a command.
222 db_command_register(struct command_table *list, struct command *cmd)
224 struct command *c, *last;
227 LIST_FOREACH(c, list, next) {
228 int n = strcmp(cmd->name, c->name);
230 /* Check that the command is not already present. */
232 printf("%s: Warning, the command \"%s\" already exists;"
233 " ignoring request\n", __func__, cmd->name);
237 /* NB: keep list sorted lexicographically */
238 LIST_INSERT_BEFORE(c, cmd, next);
244 LIST_INSERT_HEAD(list, cmd, next);
246 LIST_INSERT_AFTER(last, cmd, next);
250 * Remove a command previously registered with db_command_register.
253 db_command_unregister(struct command_table *list, struct command *cmd)
257 LIST_FOREACH(c, list, next) {
259 LIST_REMOVE(cmd, next);
263 /* NB: intentionally quiet */
267 * Helper function to match a single command.
270 db_cmd_match(char *name, struct command *cmd, struct command **cmdp,
278 while ((c = *lp) == *rp) {
282 *resultp = CMD_UNIQUE;
289 /* end of name, not end of command -
291 if (*resultp == CMD_FOUND) {
292 *resultp = CMD_AMBIGUOUS;
293 /* but keep looking for a full match -
294 this lets us match single letters */
297 *resultp = CMD_FOUND;
303 * Search for command prefix.
306 db_cmd_search(char *name, struct command_table *table, struct command **cmdp)
309 int result = CMD_NONE;
311 LIST_FOREACH(cmd, table, next) {
312 db_cmd_match(name,cmd,cmdp,&result);
313 if (result == CMD_UNIQUE)
317 if (result == CMD_NONE) {
318 /* check for 'help' */
319 if (name[0] == 'h' && name[1] == 'e'
320 && name[2] == 'l' && name[3] == 'p')
327 db_cmd_list(struct command_table *table)
330 int have_subcommands;
332 have_subcommands = 0;
333 LIST_FOREACH(cmd, table, next) {
334 if (cmd->more != NULL)
336 db_printf("%-16s", cmd->name);
340 if (have_subcommands > 0) {
341 db_printf("\nThe following have subcommands; append \"help\" "
342 "to list (e.g. \"show help\"):\n");
343 LIST_FOREACH(cmd, table, next) {
344 if (cmd->more == NULL)
346 db_printf("%-16s", cmd->name);
353 db_command(struct command **last_cmdp, struct command_table *cmd_table,
356 struct command *cmd = NULL;
358 char modif[TOK_STRING_SIZE];
359 db_expr_t addr, count;
360 bool have_addr = false;
365 /* empty line repeats last command, at 'next' */
367 addr = (db_expr_t)db_next;
372 else if (t == tEXCL) {
373 db_fncall((db_expr_t)0, (bool)false, (db_expr_t)0, (char *)0);
376 else if (t != tIDENT) {
377 db_printf("Unrecognized input; use \"help\" "
378 "to list available commands\n");
387 result = db_cmd_search(db_tok_string,
392 db_printf("No such command; use \"help\" "
393 "to list available commands\n");
397 db_printf("Ambiguous\n");
401 if (cmd_table == &db_cmd_table) {
402 db_printf("This is ddb(4), the kernel debugger; "
403 "see https://man.FreeBSD.org/ddb/4 for help.\n");
404 db_printf("Use \"bt\" for backtrace, \"dump\" for "
405 "kernel core dump, \"reset\" to reboot.\n");
406 db_printf("Available commands:\n");
408 db_cmd_list(cmd_table);
414 if ((cmd_table = cmd->more) != NULL) {
417 db_printf("Subcommand required; "
418 "available subcommands:\n");
419 db_cmd_list(cmd_table);
426 if ((cmd->flag & CS_OWN) == 0) {
429 * command [/modifier] [addr] [,count]
435 db_printf("Bad modifier\n");
439 db_strcpy(modif, db_tok_string);
446 if (db_expression(&addr)) {
447 db_dot = (db_addr_t) addr;
448 db_last_addr = db_dot;
452 addr = (db_expr_t) db_dot;
457 if (!db_expression(&count)) {
458 db_printf("Count missing\n");
467 if ((cmd->flag & CS_MORE) == 0) {
475 * Execute the command.
481 (*cmd->fcn)(addr, have_addr, count, modif);
485 if (cmd->flag & CS_SET_DOT) {
487 * If command changes dot, set dot to
488 * previous address displayed (if 'ed' style).
499 * If command does not change dot,
500 * set 'next' location to be the same.
508 * At least one non-optional command must be implemented using
509 * DB_COMMAND() so that db_cmd_set gets created. Here is one.
511 DB_COMMAND(panic, db_panic)
514 panic("from debugger");
518 db_command_loop(void)
521 * Initialize 'prev' and 'next' to dot.
526 db_cmd_loop_done = 0;
527 while (!db_cmd_loop_done) {
528 if (db_print_position() != 0)
532 (void) db_read_line();
534 db_command(&db_last_command, &db_cmd_table, /* dopager */ 1);
539 * Execute a command on behalf of a script. The caller is responsible for
540 * making sure that the command string is < DB_MAXLINE or it will be
543 * XXXRW: Runs by injecting faked input into DDB input stream; it would be
544 * nicer to use an alternative approach that didn't mess with the previous
548 db_command_script(const char *command)
550 db_prev = db_next = db_dot;
551 db_inject_line(command);
552 db_command(&db_last_command, &db_cmd_table, /* dopager */ 0);
556 db_error(const char *s)
561 kdb_reenter_silent();
565 db_dump(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
569 if (textdump_pending) {
570 db_printf("textdump_pending set.\n"
571 "run \"textdump unset\" first or \"textdump dump\" for a textdump.\n");
574 error = doadump(false);
576 db_printf("Cannot dump: ");
579 db_printf("debugger got invoked while dumping.\n");
582 db_printf("no dump device specified.\n");
585 db_printf("unknown error (error=%d).\n", error);
592 * Call random function:
596 /* The generic implementation supports a maximum of 10 arguments. */
597 typedef db_expr_t __db_f(db_expr_t, db_expr_t, db_expr_t, db_expr_t,
598 db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t, db_expr_t);
601 db_fncall_generic(db_expr_t addr, db_expr_t *rv, int nargs, db_expr_t args[])
603 __db_f *f = (__db_f *)addr;
606 db_printf("Too many arguments (max 10)\n");
609 *rv = (*f)(args[0], args[1], args[2], args[3], args[4], args[5],
610 args[6], args[7], args[8], args[9]);
615 db_fncall(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
618 db_expr_t args[DB_MAXARGS];
623 if (!db_expression(&fn_addr)) {
624 db_printf("Bad function\n");
631 if (db_expression(&args[0])) {
633 while ((t = db_read_token()) == tCOMMA) {
634 if (nargs == DB_MAXARGS) {
635 db_printf("Too many arguments (max %d)\n", DB_MAXARGS);
639 if (!db_expression(&args[nargs])) {
640 db_printf("Argument missing\n");
648 if (db_read_token() != tRPAREN) {
649 db_printf("Mismatched parens\n");
657 if (DB_CALL(fn_addr, &retval, nargs, args))
658 db_printf("= %#lr\n", (long)retval);
662 db_halt(db_expr_t dummy, bool dummy2, db_expr_t dummy3, char *dummy4)
669 db_kill(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
671 db_expr_t old_radix, pid, sig;
674 #define DB_ERROR(f) do { db_printf f; db_flush_lex(); goto out; } while (0)
677 * PIDs and signal numbers are typically represented in base
678 * 10, so make that the default here. It can, of course, be
679 * overridden by specifying a prefix.
681 old_radix = db_radix;
683 /* Retrieve arguments. */
684 if (!db_expression(&sig))
685 DB_ERROR(("Missing signal number\n"));
686 if (!db_expression(&pid))
687 DB_ERROR(("Missing process ID\n"));
689 if (!_SIG_VALID(sig))
690 DB_ERROR(("Signal number out of range\n"));
693 * Find the process in question. allproc_lock is not needed
694 * since we're in DDB.
696 /* sx_slock(&allproc_lock); */
697 FOREACH_PROC_IN_SYSTEM(p)
700 /* sx_sunlock(&allproc_lock); */
702 DB_ERROR(("Can't find process with pid %ld\n", (long) pid));
704 /* If it's already locked, bail; otherwise, do the deed. */
705 if (PROC_TRYLOCK(p) == 0)
706 DB_ERROR(("Can't lock process with pid %ld\n", (long) pid));
708 pksignal(p, sig, NULL);
713 db_radix = old_radix;
718 * Reboot. In case there is an additional argument, take it as delay in
719 * seconds. Default to 15s if we cannot parse it and make sure we will
720 * never wait longer than 1 week. Some code is similar to
721 * kern_shutdown.c:shutdown_panic().
723 #ifndef DB_RESET_MAXDELAY
724 #define DB_RESET_MAXDELAY (3600 * 24 * 7)
728 db_reset(db_expr_t addr, bool have_addr, db_expr_t count __unused,
729 char *modif __unused)
734 delay = (int)db_hex2dec(addr);
736 /* If we parse to fail, use 15s. */
740 /* Cap at one week. */
741 if ((uintmax_t)delay > (uintmax_t)DB_RESET_MAXDELAY)
742 delay = DB_RESET_MAXDELAY;
744 db_printf("Automatic reboot in %d seconds - "
745 "press a key on the console to abort\n", delay);
746 for (loop = delay * 10; loop > 0; --loop) {
747 DELAY(1000 * 100); /* 1/10th second */
748 /* Did user type a key? */
749 if (cncheckc() != -1)
758 db_watchdog(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
760 db_expr_t old_radix, tout;
763 old_radix = db_radix;
765 err = db_expression(&tout);
767 db_radix = old_radix;
769 /* If no argument is provided the watchdog will just be disabled. */
771 db_printf("No argument provided, disabling watchdog\n");
773 } else if ((tout & WD_INTERVAL) == WD_TO_NEVER) {
774 db_error("Out of range watchdog interval\n");
777 EVENTHANDLER_INVOKE(watchdog_list, tout, &i);
781 db_gdb(db_expr_t dummy1, bool dummy2, db_expr_t dummy3, char *dummy4)
784 if (kdb_dbbe_select("gdb") != 0) {
785 db_printf("The remote GDB backend could not be selected.\n");
789 * Mark that we are done in the debugger. kdb_trap()
790 * should re-enter with the new backend.
792 db_cmd_loop_done = 1;
793 db_printf("(ctrl-c will return control to ddb)\n");
797 db_stack_trace(db_expr_t tid, bool hastid, db_expr_t count, char *modif)
805 * We parse our own arguments. We don't like the default radix.
809 hastid = db_expression(&tid);
812 if (!db_expression(&count)) {
813 db_printf("Count missing\n");
825 td = kdb_thr_lookup((lwpid_t)tid);
827 td = kdb_thr_from_pid((pid_t)tid);
829 db_printf("Thread %d not found\n", (int)tid);
834 if (td->td_proc != NULL)
835 pid = td->td_proc->p_pid;
838 db_printf("Tracing pid %d tid %ld td %p\n", pid, (long)td->td_tid, td);
839 db_trace_thread(td, count);
843 _db_stack_trace_all(bool active_only)
850 FOREACH_PROC_IN_SYSTEM(p) {
851 prev_jb = kdb_jmpbuf(jb);
852 if (setjmp(jb) == 0) {
853 FOREACH_THREAD_IN_PROC(p, td) {
854 if (td->td_state == TDS_RUNNING)
855 db_printf("\nTracing command %s pid %d"
856 " tid %ld td %p (CPU %d)\n",
858 (long)td->td_tid, td,
860 else if (active_only)
863 db_printf("\nTracing command %s pid %d"
864 " tid %ld td %p\n", p->p_comm,
865 p->p_pid, (long)td->td_tid, td);
866 db_trace_thread(td, -1);
878 db_stack_trace_active(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
882 _db_stack_trace_all(true);
886 db_stack_trace_all(db_expr_t dummy, bool dummy2, db_expr_t dummy3,
890 _db_stack_trace_all(false);
894 * Take the parsed expression value from the command line that was parsed
895 * as a hexadecimal value and convert it as if the expression was parsed
896 * as a decimal value. Returns -1 if the expression was not a valid
900 db_hex2dec(db_expr_t expr)
911 val += (x % 16) * (y);