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1/*
2 * Kernel Debugger Architecture Independent Main Code
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
11 * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
12 */
13
14#include <linux/ctype.h>
15#include <linux/types.h>
16#include <linux/string.h>
17#include <linux/kernel.h>
18#include <linux/kmsg_dump.h>
19#include <linux/reboot.h>
20#include <linux/sched.h>
21#include <linux/sched/loadavg.h>
22#include <linux/sched/stat.h>
23#include <linux/sched/debug.h>
24#include <linux/sysrq.h>
25#include <linux/smp.h>
26#include <linux/utsname.h>
27#include <linux/vmalloc.h>
28#include <linux/atomic.h>
29#include <linux/module.h>
30#include <linux/moduleparam.h>
31#include <linux/mm.h>
32#include <linux/init.h>
33#include <linux/kallsyms.h>
34#include <linux/kgdb.h>
35#include <linux/kdb.h>
36#include <linux/notifier.h>
37#include <linux/interrupt.h>
38#include <linux/delay.h>
39#include <linux/nmi.h>
40#include <linux/time.h>
41#include <linux/ptrace.h>
42#include <linux/sysctl.h>
43#include <linux/cpu.h>
44#include <linux/kdebug.h>
45#include <linux/proc_fs.h>
46#include <linux/uaccess.h>
47#include <linux/slab.h>
48#include "kdb_private.h"
49
50#undef MODULE_PARAM_PREFIX
51#define MODULE_PARAM_PREFIX "kdb."
52
53static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
54module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
55
56char kdb_grep_string[KDB_GREP_STRLEN];
57int kdb_grepping_flag;
58EXPORT_SYMBOL(kdb_grepping_flag);
59int kdb_grep_leading;
60int kdb_grep_trailing;
61
62/*
63 * Kernel debugger state flags
64 */
65int kdb_flags;
66
67/*
68 * kdb_lock protects updates to kdb_initial_cpu. Used to
69 * single thread processors through the kernel debugger.
70 */
71int kdb_initial_cpu = -1; /* cpu number that owns kdb */
72int kdb_nextline = 1;
73int kdb_state; /* General KDB state */
74
75struct task_struct *kdb_current_task;
76EXPORT_SYMBOL(kdb_current_task);
77struct pt_regs *kdb_current_regs;
78
79const char *kdb_diemsg;
80static int kdb_go_count;
81#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
82static unsigned int kdb_continue_catastrophic =
83 CONFIG_KDB_CONTINUE_CATASTROPHIC;
84#else
85static unsigned int kdb_continue_catastrophic;
86#endif
87
88/* kdb_commands describes the available commands. */
89static kdbtab_t *kdb_commands;
90#define KDB_BASE_CMD_MAX 50
91static int kdb_max_commands = KDB_BASE_CMD_MAX;
92static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX];
93#define for_each_kdbcmd(cmd, num) \
94 for ((cmd) = kdb_base_commands, (num) = 0; \
95 num < kdb_max_commands; \
96 num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++)
97
98typedef struct _kdbmsg {
99 int km_diag; /* kdb diagnostic */
100 char *km_msg; /* Corresponding message text */
101} kdbmsg_t;
102
103#define KDBMSG(msgnum, text) \
104 { KDB_##msgnum, text }
105
106static kdbmsg_t kdbmsgs[] = {
107 KDBMSG(NOTFOUND, "Command Not Found"),
108 KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
109 KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
110 "8 is only allowed on 64 bit systems"),
111 KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
112 KDBMSG(NOTENV, "Cannot find environment variable"),
113 KDBMSG(NOENVVALUE, "Environment variable should have value"),
114 KDBMSG(NOTIMP, "Command not implemented"),
115 KDBMSG(ENVFULL, "Environment full"),
116 KDBMSG(ENVBUFFULL, "Environment buffer full"),
117 KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
118#ifdef CONFIG_CPU_XSCALE
119 KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
120#else
121 KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
122#endif
123 KDBMSG(DUPBPT, "Duplicate breakpoint address"),
124 KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
125 KDBMSG(BADMODE, "Invalid IDMODE"),
126 KDBMSG(BADINT, "Illegal numeric value"),
127 KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
128 KDBMSG(BADREG, "Invalid register name"),
129 KDBMSG(BADCPUNUM, "Invalid cpu number"),
130 KDBMSG(BADLENGTH, "Invalid length field"),
131 KDBMSG(NOBP, "No Breakpoint exists"),
132 KDBMSG(BADADDR, "Invalid address"),
133 KDBMSG(NOPERM, "Permission denied"),
134};
135#undef KDBMSG
136
137static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
138
139
140/*
141 * Initial environment. This is all kept static and local to
142 * this file. We don't want to rely on the memory allocation
143 * mechanisms in the kernel, so we use a very limited allocate-only
144 * heap for new and altered environment variables. The entire
145 * environment is limited to a fixed number of entries (add more
146 * to __env[] if required) and a fixed amount of heap (add more to
147 * KDB_ENVBUFSIZE if required).
148 */
149
150static char *__env[] = {
151#if defined(CONFIG_SMP)
152 "PROMPT=[%d]kdb> ",
153#else
154 "PROMPT=kdb> ",
155#endif
156 "MOREPROMPT=more> ",
157 "RADIX=16",
158 "MDCOUNT=8", /* lines of md output */
159 KDB_PLATFORM_ENV,
160 "DTABCOUNT=30",
161 "NOSECT=1",
162 (char *)0,
163 (char *)0,
164 (char *)0,
165 (char *)0,
166 (char *)0,
167 (char *)0,
168 (char *)0,
169 (char *)0,
170 (char *)0,
171 (char *)0,
172 (char *)0,
173 (char *)0,
174 (char *)0,
175 (char *)0,
176 (char *)0,
177 (char *)0,
178 (char *)0,
179 (char *)0,
180 (char *)0,
181 (char *)0,
182 (char *)0,
183 (char *)0,
184 (char *)0,
185 (char *)0,
186};
187
188static const int __nenv = ARRAY_SIZE(__env);
189
190struct task_struct *kdb_curr_task(int cpu)
191{
192 struct task_struct *p = curr_task(cpu);
193#ifdef _TIF_MCA_INIT
194 if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
195 p = krp->p;
196#endif
197 return p;
198}
199
200/*
201 * Check whether the flags of the current command and the permissions
202 * of the kdb console has allow a command to be run.
203 */
204static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
205 bool no_args)
206{
207 /* permissions comes from userspace so needs massaging slightly */
208 permissions &= KDB_ENABLE_MASK;
209 permissions |= KDB_ENABLE_ALWAYS_SAFE;
210
211 /* some commands change group when launched with no arguments */
212 if (no_args)
213 permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
214
215 flags |= KDB_ENABLE_ALL;
216
217 return permissions & flags;
218}
219
220/*
221 * kdbgetenv - This function will return the character string value of
222 * an environment variable.
223 * Parameters:
224 * match A character string representing an environment variable.
225 * Returns:
226 * NULL No environment variable matches 'match'
227 * char* Pointer to string value of environment variable.
228 */
229char *kdbgetenv(const char *match)
230{
231 char **ep = __env;
232 int matchlen = strlen(match);
233 int i;
234
235 for (i = 0; i < __nenv; i++) {
236 char *e = *ep++;
237
238 if (!e)
239 continue;
240
241 if ((strncmp(match, e, matchlen) == 0)
242 && ((e[matchlen] == '\0')
243 || (e[matchlen] == '='))) {
244 char *cp = strchr(e, '=');
245 return cp ? ++cp : "";
246 }
247 }
248 return NULL;
249}
250
251/*
252 * kdballocenv - This function is used to allocate bytes for
253 * environment entries.
254 * Parameters:
255 * match A character string representing a numeric value
256 * Outputs:
257 * *value the unsigned long representation of the env variable 'match'
258 * Returns:
259 * Zero on success, a kdb diagnostic on failure.
260 * Remarks:
261 * We use a static environment buffer (envbuffer) to hold the values
262 * of dynamically generated environment variables (see kdb_set). Buffer
263 * space once allocated is never free'd, so over time, the amount of space
264 * (currently 512 bytes) will be exhausted if env variables are changed
265 * frequently.
266 */
267static char *kdballocenv(size_t bytes)
268{
269#define KDB_ENVBUFSIZE 512
270 static char envbuffer[KDB_ENVBUFSIZE];
271 static int envbufsize;
272 char *ep = NULL;
273
274 if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
275 ep = &envbuffer[envbufsize];
276 envbufsize += bytes;
277 }
278 return ep;
279}
280
281/*
282 * kdbgetulenv - This function will return the value of an unsigned
283 * long-valued environment variable.
284 * Parameters:
285 * match A character string representing a numeric value
286 * Outputs:
287 * *value the unsigned long represntation of the env variable 'match'
288 * Returns:
289 * Zero on success, a kdb diagnostic on failure.
290 */
291static int kdbgetulenv(const char *match, unsigned long *value)
292{
293 char *ep;
294
295 ep = kdbgetenv(match);
296 if (!ep)
297 return KDB_NOTENV;
298 if (strlen(ep) == 0)
299 return KDB_NOENVVALUE;
300
301 *value = simple_strtoul(ep, NULL, 0);
302
303 return 0;
304}
305
306/*
307 * kdbgetintenv - This function will return the value of an
308 * integer-valued environment variable.
309 * Parameters:
310 * match A character string representing an integer-valued env variable
311 * Outputs:
312 * *value the integer representation of the environment variable 'match'
313 * Returns:
314 * Zero on success, a kdb diagnostic on failure.
315 */
316int kdbgetintenv(const char *match, int *value)
317{
318 unsigned long val;
319 int diag;
320
321 diag = kdbgetulenv(match, &val);
322 if (!diag)
323 *value = (int) val;
324 return diag;
325}
326
327/*
328 * kdbgetularg - This function will convert a numeric string into an
329 * unsigned long value.
330 * Parameters:
331 * arg A character string representing a numeric value
332 * Outputs:
333 * *value the unsigned long represntation of arg.
334 * Returns:
335 * Zero on success, a kdb diagnostic on failure.
336 */
337int kdbgetularg(const char *arg, unsigned long *value)
338{
339 char *endp;
340 unsigned long val;
341
342 val = simple_strtoul(arg, &endp, 0);
343
344 if (endp == arg) {
345 /*
346 * Also try base 16, for us folks too lazy to type the
347 * leading 0x...
348 */
349 val = simple_strtoul(arg, &endp, 16);
350 if (endp == arg)
351 return KDB_BADINT;
352 }
353
354 *value = val;
355
356 return 0;
357}
358
359int kdbgetu64arg(const char *arg, u64 *value)
360{
361 char *endp;
362 u64 val;
363
364 val = simple_strtoull(arg, &endp, 0);
365
366 if (endp == arg) {
367
368 val = simple_strtoull(arg, &endp, 16);
369 if (endp == arg)
370 return KDB_BADINT;
371 }
372
373 *value = val;
374
375 return 0;
376}
377
378/*
379 * kdb_set - This function implements the 'set' command. Alter an
380 * existing environment variable or create a new one.
381 */
382int kdb_set(int argc, const char **argv)
383{
384 int i;
385 char *ep;
386 size_t varlen, vallen;
387
388 /*
389 * we can be invoked two ways:
390 * set var=value argv[1]="var", argv[2]="value"
391 * set var = value argv[1]="var", argv[2]="=", argv[3]="value"
392 * - if the latter, shift 'em down.
393 */
394 if (argc == 3) {
395 argv[2] = argv[3];
396 argc--;
397 }
398
399 if (argc != 2)
400 return KDB_ARGCOUNT;
401
402 /*
403 * Check for internal variables
404 */
405 if (strcmp(argv[1], "KDBDEBUG") == 0) {
406 unsigned int debugflags;
407 char *cp;
408
409 debugflags = simple_strtoul(argv[2], &cp, 0);
410 if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
411 kdb_printf("kdb: illegal debug flags '%s'\n",
412 argv[2]);
413 return 0;
414 }
415 kdb_flags = (kdb_flags &
416 ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
417 | (debugflags << KDB_DEBUG_FLAG_SHIFT);
418
419 return 0;
420 }
421
422 /*
423 * Tokenizer squashed the '=' sign. argv[1] is variable
424 * name, argv[2] = value.
425 */
426 varlen = strlen(argv[1]);
427 vallen = strlen(argv[2]);
428 ep = kdballocenv(varlen + vallen + 2);
429 if (ep == (char *)0)
430 return KDB_ENVBUFFULL;
431
432 sprintf(ep, "%s=%s", argv[1], argv[2]);
433
434 ep[varlen+vallen+1] = '\0';
435
436 for (i = 0; i < __nenv; i++) {
437 if (__env[i]
438 && ((strncmp(__env[i], argv[1], varlen) == 0)
439 && ((__env[i][varlen] == '\0')
440 || (__env[i][varlen] == '=')))) {
441 __env[i] = ep;
442 return 0;
443 }
444 }
445
446 /*
447 * Wasn't existing variable. Fit into slot.
448 */
449 for (i = 0; i < __nenv-1; i++) {
450 if (__env[i] == (char *)0) {
451 __env[i] = ep;
452 return 0;
453 }
454 }
455
456 return KDB_ENVFULL;
457}
458
459static int kdb_check_regs(void)
460{
461 if (!kdb_current_regs) {
462 kdb_printf("No current kdb registers."
463 " You may need to select another task\n");
464 return KDB_BADREG;
465 }
466 return 0;
467}
468
469/*
470 * kdbgetaddrarg - This function is responsible for parsing an
471 * address-expression and returning the value of the expression,
472 * symbol name, and offset to the caller.
473 *
474 * The argument may consist of a numeric value (decimal or
475 * hexidecimal), a symbol name, a register name (preceded by the
476 * percent sign), an environment variable with a numeric value
477 * (preceded by a dollar sign) or a simple arithmetic expression
478 * consisting of a symbol name, +/-, and a numeric constant value
479 * (offset).
480 * Parameters:
481 * argc - count of arguments in argv
482 * argv - argument vector
483 * *nextarg - index to next unparsed argument in argv[]
484 * regs - Register state at time of KDB entry
485 * Outputs:
486 * *value - receives the value of the address-expression
487 * *offset - receives the offset specified, if any
488 * *name - receives the symbol name, if any
489 * *nextarg - index to next unparsed argument in argv[]
490 * Returns:
491 * zero is returned on success, a kdb diagnostic code is
492 * returned on error.
493 */
494int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
495 unsigned long *value, long *offset,
496 char **name)
497{
498 unsigned long addr;
499 unsigned long off = 0;
500 int positive;
501 int diag;
502 int found = 0;
503 char *symname;
504 char symbol = '\0';
505 char *cp;
506 kdb_symtab_t symtab;
507
508 /*
509 * If the enable flags prohibit both arbitrary memory access
510 * and flow control then there are no reasonable grounds to
511 * provide symbol lookup.
512 */
513 if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
514 kdb_cmd_enabled, false))
515 return KDB_NOPERM;
516
517 /*
518 * Process arguments which follow the following syntax:
519 *
520 * symbol | numeric-address [+/- numeric-offset]
521 * %register
522 * $environment-variable
523 */
524
525 if (*nextarg > argc)
526 return KDB_ARGCOUNT;
527
528 symname = (char *)argv[*nextarg];
529
530 /*
531 * If there is no whitespace between the symbol
532 * or address and the '+' or '-' symbols, we
533 * remember the character and replace it with a
534 * null so the symbol/value can be properly parsed
535 */
536 cp = strpbrk(symname, "+-");
537 if (cp != NULL) {
538 symbol = *cp;
539 *cp++ = '\0';
540 }
541
542 if (symname[0] == '$') {
543 diag = kdbgetulenv(&symname[1], &addr);
544 if (diag)
545 return diag;
546 } else if (symname[0] == '%') {
547 diag = kdb_check_regs();
548 if (diag)
549 return diag;
550 /* Implement register values with % at a later time as it is
551 * arch optional.
552 */
553 return KDB_NOTIMP;
554 } else {
555 found = kdbgetsymval(symname, &symtab);
556 if (found) {
557 addr = symtab.sym_start;
558 } else {
559 diag = kdbgetularg(argv[*nextarg], &addr);
560 if (diag)
561 return diag;
562 }
563 }
564
565 if (!found)
566 found = kdbnearsym(addr, &symtab);
567
568 (*nextarg)++;
569
570 if (name)
571 *name = symname;
572 if (value)
573 *value = addr;
574 if (offset && name && *name)
575 *offset = addr - symtab.sym_start;
576
577 if ((*nextarg > argc)
578 && (symbol == '\0'))
579 return 0;
580
581 /*
582 * check for +/- and offset
583 */
584
585 if (symbol == '\0') {
586 if ((argv[*nextarg][0] != '+')
587 && (argv[*nextarg][0] != '-')) {
588 /*
589 * Not our argument. Return.
590 */
591 return 0;
592 } else {
593 positive = (argv[*nextarg][0] == '+');
594 (*nextarg)++;
595 }
596 } else
597 positive = (symbol == '+');
598
599 /*
600 * Now there must be an offset!
601 */
602 if ((*nextarg > argc)
603 && (symbol == '\0')) {
604 return KDB_INVADDRFMT;
605 }
606
607 if (!symbol) {
608 cp = (char *)argv[*nextarg];
609 (*nextarg)++;
610 }
611
612 diag = kdbgetularg(cp, &off);
613 if (diag)
614 return diag;
615
616 if (!positive)
617 off = -off;
618
619 if (offset)
620 *offset += off;
621
622 if (value)
623 *value += off;
624
625 return 0;
626}
627
628static void kdb_cmderror(int diag)
629{
630 int i;
631
632 if (diag >= 0) {
633 kdb_printf("no error detected (diagnostic is %d)\n", diag);
634 return;
635 }
636
637 for (i = 0; i < __nkdb_err; i++) {
638 if (kdbmsgs[i].km_diag == diag) {
639 kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
640 return;
641 }
642 }
643
644 kdb_printf("Unknown diag %d\n", -diag);
645}
646
647/*
648 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
649 * command which defines one command as a set of other commands,
650 * terminated by endefcmd. kdb_defcmd processes the initial
651 * 'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
652 * the following commands until 'endefcmd'.
653 * Inputs:
654 * argc argument count
655 * argv argument vector
656 * Returns:
657 * zero for success, a kdb diagnostic if error
658 */
659struct defcmd_set {
660 int count;
661 bool usable;
662 char *name;
663 char *usage;
664 char *help;
665 char **command;
666};
667static struct defcmd_set *defcmd_set;
668static int defcmd_set_count;
669static bool defcmd_in_progress;
670
671/* Forward references */
672static int kdb_exec_defcmd(int argc, const char **argv);
673
674static int kdb_defcmd2(const char *cmdstr, const char *argv0)
675{
676 struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
677 char **save_command = s->command;
678 if (strcmp(argv0, "endefcmd") == 0) {
679 defcmd_in_progress = false;
680 if (!s->count)
681 s->usable = false;
682 if (s->usable)
683 /* macros are always safe because when executed each
684 * internal command re-enters kdb_parse() and is
685 * safety checked individually.
686 */
687 kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
688 s->help, 0,
689 KDB_ENABLE_ALWAYS_SAFE);
690 return 0;
691 }
692 if (!s->usable)
693 return KDB_NOTIMP;
694 s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);
695 if (!s->command) {
696 kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
697 cmdstr);
698 s->usable = false;
699 return KDB_NOTIMP;
700 }
701 memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
702 s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
703 kfree(save_command);
704 return 0;
705}
706
707static int kdb_defcmd(int argc, const char **argv)
708{
709 struct defcmd_set *save_defcmd_set = defcmd_set, *s;
710 if (defcmd_in_progress) {
711 kdb_printf("kdb: nested defcmd detected, assuming missing "
712 "endefcmd\n");
713 kdb_defcmd2("endefcmd", "endefcmd");
714 }
715 if (argc == 0) {
716 int i;
717 for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
718 kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
719 s->usage, s->help);
720 for (i = 0; i < s->count; ++i)
721 kdb_printf("%s", s->command[i]);
722 kdb_printf("endefcmd\n");
723 }
724 return 0;
725 }
726 if (argc != 3)
727 return KDB_ARGCOUNT;
728 if (in_dbg_master()) {
729 kdb_printf("Command only available during kdb_init()\n");
730 return KDB_NOTIMP;
731 }
732 defcmd_set = kmalloc_array(defcmd_set_count + 1, sizeof(*defcmd_set),
733 GFP_KDB);
734 if (!defcmd_set)
735 goto fail_defcmd;
736 memcpy(defcmd_set, save_defcmd_set,
737 defcmd_set_count * sizeof(*defcmd_set));
738 s = defcmd_set + defcmd_set_count;
739 memset(s, 0, sizeof(*s));
740 s->usable = true;
741 s->name = kdb_strdup(argv[1], GFP_KDB);
742 if (!s->name)
743 goto fail_name;
744 s->usage = kdb_strdup(argv[2], GFP_KDB);
745 if (!s->usage)
746 goto fail_usage;
747 s->help = kdb_strdup(argv[3], GFP_KDB);
748 if (!s->help)
749 goto fail_help;
750 if (s->usage[0] == '"') {
751 strcpy(s->usage, argv[2]+1);
752 s->usage[strlen(s->usage)-1] = '\0';
753 }
754 if (s->help[0] == '"') {
755 strcpy(s->help, argv[3]+1);
756 s->help[strlen(s->help)-1] = '\0';
757 }
758 ++defcmd_set_count;
759 defcmd_in_progress = true;
760 kfree(save_defcmd_set);
761 return 0;
762fail_help:
763 kfree(s->usage);
764fail_usage:
765 kfree(s->name);
766fail_name:
767 kfree(defcmd_set);
768fail_defcmd:
769 kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
770 defcmd_set = save_defcmd_set;
771 return KDB_NOTIMP;
772}
773
774/*
775 * kdb_exec_defcmd - Execute the set of commands associated with this
776 * defcmd name.
777 * Inputs:
778 * argc argument count
779 * argv argument vector
780 * Returns:
781 * zero for success, a kdb diagnostic if error
782 */
783static int kdb_exec_defcmd(int argc, const char **argv)
784{
785 int i, ret;
786 struct defcmd_set *s;
787 if (argc != 0)
788 return KDB_ARGCOUNT;
789 for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
790 if (strcmp(s->name, argv[0]) == 0)
791 break;
792 }
793 if (i == defcmd_set_count) {
794 kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
795 argv[0]);
796 return KDB_NOTIMP;
797 }
798 for (i = 0; i < s->count; ++i) {
799 /* Recursive use of kdb_parse, do not use argv after
800 * this point */
801 argv = NULL;
802 kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
803 ret = kdb_parse(s->command[i]);
804 if (ret)
805 return ret;
806 }
807 return 0;
808}
809
810/* Command history */
811#define KDB_CMD_HISTORY_COUNT 32
812#define CMD_BUFLEN 200 /* kdb_printf: max printline
813 * size == 256 */
814static unsigned int cmd_head, cmd_tail;
815static unsigned int cmdptr;
816static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
817static char cmd_cur[CMD_BUFLEN];
818
819/*
820 * The "str" argument may point to something like | grep xyz
821 */
822static void parse_grep(const char *str)
823{
824 int len;
825 char *cp = (char *)str, *cp2;
826
827 /* sanity check: we should have been called with the \ first */
828 if (*cp != '|')
829 return;
830 cp++;
831 while (isspace(*cp))
832 cp++;
833 if (!str_has_prefix(cp, "grep ")) {
834 kdb_printf("invalid 'pipe', see grephelp\n");
835 return;
836 }
837 cp += 5;
838 while (isspace(*cp))
839 cp++;
840 cp2 = strchr(cp, '\n');
841 if (cp2)
842 *cp2 = '\0'; /* remove the trailing newline */
843 len = strlen(cp);
844 if (len == 0) {
845 kdb_printf("invalid 'pipe', see grephelp\n");
846 return;
847 }
848 /* now cp points to a nonzero length search string */
849 if (*cp == '"') {
850 /* allow it be "x y z" by removing the "'s - there must
851 be two of them */
852 cp++;
853 cp2 = strchr(cp, '"');
854 if (!cp2) {
855 kdb_printf("invalid quoted string, see grephelp\n");
856 return;
857 }
858 *cp2 = '\0'; /* end the string where the 2nd " was */
859 }
860 kdb_grep_leading = 0;
861 if (*cp == '^') {
862 kdb_grep_leading = 1;
863 cp++;
864 }
865 len = strlen(cp);
866 kdb_grep_trailing = 0;
867 if (*(cp+len-1) == '$') {
868 kdb_grep_trailing = 1;
869 *(cp+len-1) = '\0';
870 }
871 len = strlen(cp);
872 if (!len)
873 return;
874 if (len >= KDB_GREP_STRLEN) {
875 kdb_printf("search string too long\n");
876 return;
877 }
878 strcpy(kdb_grep_string, cp);
879 kdb_grepping_flag++;
880 return;
881}
882
883/*
884 * kdb_parse - Parse the command line, search the command table for a
885 * matching command and invoke the command function. This
886 * function may be called recursively, if it is, the second call
887 * will overwrite argv and cbuf. It is the caller's
888 * responsibility to save their argv if they recursively call
889 * kdb_parse().
890 * Parameters:
891 * cmdstr The input command line to be parsed.
892 * regs The registers at the time kdb was entered.
893 * Returns:
894 * Zero for success, a kdb diagnostic if failure.
895 * Remarks:
896 * Limited to 20 tokens.
897 *
898 * Real rudimentary tokenization. Basically only whitespace
899 * is considered a token delimeter (but special consideration
900 * is taken of the '=' sign as used by the 'set' command).
901 *
902 * The algorithm used to tokenize the input string relies on
903 * there being at least one whitespace (or otherwise useless)
904 * character between tokens as the character immediately following
905 * the token is altered in-place to a null-byte to terminate the
906 * token string.
907 */
908
909#define MAXARGC 20
910
911int kdb_parse(const char *cmdstr)
912{
913 static char *argv[MAXARGC];
914 static int argc;
915 static char cbuf[CMD_BUFLEN+2];
916 char *cp;
917 char *cpp, quoted;
918 kdbtab_t *tp;
919 int i, escaped, ignore_errors = 0, check_grep = 0;
920
921 /*
922 * First tokenize the command string.
923 */
924 cp = (char *)cmdstr;
925
926 if (KDB_FLAG(CMD_INTERRUPT)) {
927 /* Previous command was interrupted, newline must not
928 * repeat the command */
929 KDB_FLAG_CLEAR(CMD_INTERRUPT);
930 KDB_STATE_SET(PAGER);
931 argc = 0; /* no repeat */
932 }
933
934 if (*cp != '\n' && *cp != '\0') {
935 argc = 0;
936 cpp = cbuf;
937 while (*cp) {
938 /* skip whitespace */
939 while (isspace(*cp))
940 cp++;
941 if ((*cp == '\0') || (*cp == '\n') ||
942 (*cp == '#' && !defcmd_in_progress))
943 break;
944 /* special case: check for | grep pattern */
945 if (*cp == '|') {
946 check_grep++;
947 break;
948 }
949 if (cpp >= cbuf + CMD_BUFLEN) {
950 kdb_printf("kdb_parse: command buffer "
951 "overflow, command ignored\n%s\n",
952 cmdstr);
953 return KDB_NOTFOUND;
954 }
955 if (argc >= MAXARGC - 1) {
956 kdb_printf("kdb_parse: too many arguments, "
957 "command ignored\n%s\n", cmdstr);
958 return KDB_NOTFOUND;
959 }
960 argv[argc++] = cpp;
961 escaped = 0;
962 quoted = '\0';
963 /* Copy to next unquoted and unescaped
964 * whitespace or '=' */
965 while (*cp && *cp != '\n' &&
966 (escaped || quoted || !isspace(*cp))) {
967 if (cpp >= cbuf + CMD_BUFLEN)
968 break;
969 if (escaped) {
970 escaped = 0;
971 *cpp++ = *cp++;
972 continue;
973 }
974 if (*cp == '\\') {
975 escaped = 1;
976 ++cp;
977 continue;
978 }
979 if (*cp == quoted)
980 quoted = '\0';
981 else if (*cp == '\'' || *cp == '"')
982 quoted = *cp;
983 *cpp = *cp++;
984 if (*cpp == '=' && !quoted)
985 break;
986 ++cpp;
987 }
988 *cpp++ = '\0'; /* Squash a ws or '=' character */
989 }
990 }
991 if (!argc)
992 return 0;
993 if (check_grep)
994 parse_grep(cp);
995 if (defcmd_in_progress) {
996 int result = kdb_defcmd2(cmdstr, argv[0]);
997 if (!defcmd_in_progress) {
998 argc = 0; /* avoid repeat on endefcmd */
999 *(argv[0]) = '\0';
1000 }
1001 return result;
1002 }
1003 if (argv[0][0] == '-' && argv[0][1] &&
1004 (argv[0][1] < '0' || argv[0][1] > '9')) {
1005 ignore_errors = 1;
1006 ++argv[0];
1007 }
1008
1009 for_each_kdbcmd(tp, i) {
1010 if (tp->cmd_name) {
1011 /*
1012 * If this command is allowed to be abbreviated,
1013 * check to see if this is it.
1014 */
1015
1016 if (tp->cmd_minlen
1017 && (strlen(argv[0]) <= tp->cmd_minlen)) {
1018 if (strncmp(argv[0],
1019 tp->cmd_name,
1020 tp->cmd_minlen) == 0) {
1021 break;
1022 }
1023 }
1024
1025 if (strcmp(argv[0], tp->cmd_name) == 0)
1026 break;
1027 }
1028 }
1029
1030 /*
1031 * If we don't find a command by this name, see if the first
1032 * few characters of this match any of the known commands.
1033 * e.g., md1c20 should match md.
1034 */
1035 if (i == kdb_max_commands) {
1036 for_each_kdbcmd(tp, i) {
1037 if (tp->cmd_name) {
1038 if (strncmp(argv[0],
1039 tp->cmd_name,
1040 strlen(tp->cmd_name)) == 0) {
1041 break;
1042 }
1043 }
1044 }
1045 }
1046
1047 if (i < kdb_max_commands) {
1048 int result;
1049
1050 if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1051 return KDB_NOPERM;
1052
1053 KDB_STATE_SET(CMD);
1054 result = (*tp->cmd_func)(argc-1, (const char **)argv);
1055 if (result && ignore_errors && result > KDB_CMD_GO)
1056 result = 0;
1057 KDB_STATE_CLEAR(CMD);
1058
1059 if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1060 return result;
1061
1062 argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1063 if (argv[argc])
1064 *(argv[argc]) = '\0';
1065 return result;
1066 }
1067
1068 /*
1069 * If the input with which we were presented does not
1070 * map to an existing command, attempt to parse it as an
1071 * address argument and display the result. Useful for
1072 * obtaining the address of a variable, or the nearest symbol
1073 * to an address contained in a register.
1074 */
1075 {
1076 unsigned long value;
1077 char *name = NULL;
1078 long offset;
1079 int nextarg = 0;
1080
1081 if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1082 &value, &offset, &name)) {
1083 return KDB_NOTFOUND;
1084 }
1085
1086 kdb_printf("%s = ", argv[0]);
1087 kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1088 kdb_printf("\n");
1089 return 0;
1090 }
1091}
1092
1093
1094static int handle_ctrl_cmd(char *cmd)
1095{
1096#define CTRL_P 16
1097#define CTRL_N 14
1098
1099 /* initial situation */
1100 if (cmd_head == cmd_tail)
1101 return 0;
1102 switch (*cmd) {
1103 case CTRL_P:
1104 if (cmdptr != cmd_tail)
1105 cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
1106 strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1107 return 1;
1108 case CTRL_N:
1109 if (cmdptr != cmd_head)
1110 cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1111 strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1112 return 1;
1113 }
1114 return 0;
1115}
1116
1117/*
1118 * kdb_reboot - This function implements the 'reboot' command. Reboot
1119 * the system immediately, or loop for ever on failure.
1120 */
1121static int kdb_reboot(int argc, const char **argv)
1122{
1123 emergency_restart();
1124 kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1125 while (1)
1126 cpu_relax();
1127 /* NOTREACHED */
1128 return 0;
1129}
1130
1131static void kdb_dumpregs(struct pt_regs *regs)
1132{
1133 int old_lvl = console_loglevel;
1134 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1135 kdb_trap_printk++;
1136 show_regs(regs);
1137 kdb_trap_printk--;
1138 kdb_printf("\n");
1139 console_loglevel = old_lvl;
1140}
1141
1142void kdb_set_current_task(struct task_struct *p)
1143{
1144 kdb_current_task = p;
1145
1146 if (kdb_task_has_cpu(p)) {
1147 kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1148 return;
1149 }
1150 kdb_current_regs = NULL;
1151}
1152
1153static void drop_newline(char *buf)
1154{
1155 size_t len = strlen(buf);
1156
1157 if (len == 0)
1158 return;
1159 if (*(buf + len - 1) == '\n')
1160 *(buf + len - 1) = '\0';
1161}
1162
1163/*
1164 * kdb_local - The main code for kdb. This routine is invoked on a
1165 * specific processor, it is not global. The main kdb() routine
1166 * ensures that only one processor at a time is in this routine.
1167 * This code is called with the real reason code on the first
1168 * entry to a kdb session, thereafter it is called with reason
1169 * SWITCH, even if the user goes back to the original cpu.
1170 * Inputs:
1171 * reason The reason KDB was invoked
1172 * error The hardware-defined error code
1173 * regs The exception frame at time of fault/breakpoint.
1174 * db_result Result code from the break or debug point.
1175 * Returns:
1176 * 0 KDB was invoked for an event which it wasn't responsible
1177 * 1 KDB handled the event for which it was invoked.
1178 * KDB_CMD_GO User typed 'go'.
1179 * KDB_CMD_CPU User switched to another cpu.
1180 * KDB_CMD_SS Single step.
1181 */
1182static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1183 kdb_dbtrap_t db_result)
1184{
1185 char *cmdbuf;
1186 int diag;
1187 struct task_struct *kdb_current =
1188 kdb_curr_task(raw_smp_processor_id());
1189
1190 KDB_DEBUG_STATE("kdb_local 1", reason);
1191 kdb_go_count = 0;
1192 if (reason == KDB_REASON_DEBUG) {
1193 /* special case below */
1194 } else {
1195 kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1196 kdb_current, kdb_current ? kdb_current->pid : 0);
1197#if defined(CONFIG_SMP)
1198 kdb_printf("on processor %d ", raw_smp_processor_id());
1199#endif
1200 }
1201
1202 switch (reason) {
1203 case KDB_REASON_DEBUG:
1204 {
1205 /*
1206 * If re-entering kdb after a single step
1207 * command, don't print the message.
1208 */
1209 switch (db_result) {
1210 case KDB_DB_BPT:
1211 kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1212 kdb_current, kdb_current->pid);
1213#if defined(CONFIG_SMP)
1214 kdb_printf("on processor %d ", raw_smp_processor_id());
1215#endif
1216 kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1217 instruction_pointer(regs));
1218 break;
1219 case KDB_DB_SS:
1220 break;
1221 case KDB_DB_SSBPT:
1222 KDB_DEBUG_STATE("kdb_local 4", reason);
1223 return 1; /* kdba_db_trap did the work */
1224 default:
1225 kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1226 db_result);
1227 break;
1228 }
1229
1230 }
1231 break;
1232 case KDB_REASON_ENTER:
1233 if (KDB_STATE(KEYBOARD))
1234 kdb_printf("due to Keyboard Entry\n");
1235 else
1236 kdb_printf("due to KDB_ENTER()\n");
1237 break;
1238 case KDB_REASON_KEYBOARD:
1239 KDB_STATE_SET(KEYBOARD);
1240 kdb_printf("due to Keyboard Entry\n");
1241 break;
1242 case KDB_REASON_ENTER_SLAVE:
1243 /* drop through, slaves only get released via cpu switch */
1244 case KDB_REASON_SWITCH:
1245 kdb_printf("due to cpu switch\n");
1246 break;
1247 case KDB_REASON_OOPS:
1248 kdb_printf("Oops: %s\n", kdb_diemsg);
1249 kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1250 instruction_pointer(regs));
1251 kdb_dumpregs(regs);
1252 break;
1253 case KDB_REASON_SYSTEM_NMI:
1254 kdb_printf("due to System NonMaskable Interrupt\n");
1255 break;
1256 case KDB_REASON_NMI:
1257 kdb_printf("due to NonMaskable Interrupt @ "
1258 kdb_machreg_fmt "\n",
1259 instruction_pointer(regs));
1260 break;
1261 case KDB_REASON_SSTEP:
1262 case KDB_REASON_BREAK:
1263 kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1264 reason == KDB_REASON_BREAK ?
1265 "Breakpoint" : "SS trap", instruction_pointer(regs));
1266 /*
1267 * Determine if this breakpoint is one that we
1268 * are interested in.
1269 */
1270 if (db_result != KDB_DB_BPT) {
1271 kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1272 db_result);
1273 KDB_DEBUG_STATE("kdb_local 6", reason);
1274 return 0; /* Not for us, dismiss it */
1275 }
1276 break;
1277 case KDB_REASON_RECURSE:
1278 kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1279 instruction_pointer(regs));
1280 break;
1281 default:
1282 kdb_printf("kdb: unexpected reason code: %d\n", reason);
1283 KDB_DEBUG_STATE("kdb_local 8", reason);
1284 return 0; /* Not for us, dismiss it */
1285 }
1286
1287 while (1) {
1288 /*
1289 * Initialize pager context.
1290 */
1291 kdb_nextline = 1;
1292 KDB_STATE_CLEAR(SUPPRESS);
1293 kdb_grepping_flag = 0;
1294 /* ensure the old search does not leak into '/' commands */
1295 kdb_grep_string[0] = '\0';
1296
1297 cmdbuf = cmd_cur;
1298 *cmdbuf = '\0';
1299 *(cmd_hist[cmd_head]) = '\0';
1300
1301do_full_getstr:
1302#if defined(CONFIG_SMP)
1303 snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1304 raw_smp_processor_id());
1305#else
1306 snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
1307#endif
1308 if (defcmd_in_progress)
1309 strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1310
1311 /*
1312 * Fetch command from keyboard
1313 */
1314 cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1315 if (*cmdbuf != '\n') {
1316 if (*cmdbuf < 32) {
1317 if (cmdptr == cmd_head) {
1318 strncpy(cmd_hist[cmd_head], cmd_cur,
1319 CMD_BUFLEN);
1320 *(cmd_hist[cmd_head] +
1321 strlen(cmd_hist[cmd_head])-1) = '\0';
1322 }
1323 if (!handle_ctrl_cmd(cmdbuf))
1324 *(cmd_cur+strlen(cmd_cur)-1) = '\0';
1325 cmdbuf = cmd_cur;
1326 goto do_full_getstr;
1327 } else {
1328 strncpy(cmd_hist[cmd_head], cmd_cur,
1329 CMD_BUFLEN);
1330 }
1331
1332 cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1333 if (cmd_head == cmd_tail)
1334 cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1335 }
1336
1337 cmdptr = cmd_head;
1338 diag = kdb_parse(cmdbuf);
1339 if (diag == KDB_NOTFOUND) {
1340 drop_newline(cmdbuf);
1341 kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1342 diag = 0;
1343 }
1344 if (diag == KDB_CMD_GO
1345 || diag == KDB_CMD_CPU
1346 || diag == KDB_CMD_SS
1347 || diag == KDB_CMD_KGDB)
1348 break;
1349
1350 if (diag)
1351 kdb_cmderror(diag);
1352 }
1353 KDB_DEBUG_STATE("kdb_local 9", diag);
1354 return diag;
1355}
1356
1357
1358/*
1359 * kdb_print_state - Print the state data for the current processor
1360 * for debugging.
1361 * Inputs:
1362 * text Identifies the debug point
1363 * value Any integer value to be printed, e.g. reason code.
1364 */
1365void kdb_print_state(const char *text, int value)
1366{
1367 kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1368 text, raw_smp_processor_id(), value, kdb_initial_cpu,
1369 kdb_state);
1370}
1371
1372/*
1373 * kdb_main_loop - After initial setup and assignment of the
1374 * controlling cpu, all cpus are in this loop. One cpu is in
1375 * control and will issue the kdb prompt, the others will spin
1376 * until 'go' or cpu switch.
1377 *
1378 * To get a consistent view of the kernel stacks for all
1379 * processes, this routine is invoked from the main kdb code via
1380 * an architecture specific routine. kdba_main_loop is
1381 * responsible for making the kernel stacks consistent for all
1382 * processes, there should be no difference between a blocked
1383 * process and a running process as far as kdb is concerned.
1384 * Inputs:
1385 * reason The reason KDB was invoked
1386 * error The hardware-defined error code
1387 * reason2 kdb's current reason code.
1388 * Initially error but can change
1389 * according to kdb state.
1390 * db_result Result code from break or debug point.
1391 * regs The exception frame at time of fault/breakpoint.
1392 * should always be valid.
1393 * Returns:
1394 * 0 KDB was invoked for an event which it wasn't responsible
1395 * 1 KDB handled the event for which it was invoked.
1396 */
1397int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1398 kdb_dbtrap_t db_result, struct pt_regs *regs)
1399{
1400 int result = 1;
1401 /* Stay in kdb() until 'go', 'ss[b]' or an error */
1402 while (1) {
1403 /*
1404 * All processors except the one that is in control
1405 * will spin here.
1406 */
1407 KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1408 while (KDB_STATE(HOLD_CPU)) {
1409 /* state KDB is turned off by kdb_cpu to see if the
1410 * other cpus are still live, each cpu in this loop
1411 * turns it back on.
1412 */
1413 if (!KDB_STATE(KDB))
1414 KDB_STATE_SET(KDB);
1415 }
1416
1417 KDB_STATE_CLEAR(SUPPRESS);
1418 KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1419 if (KDB_STATE(LEAVING))
1420 break; /* Another cpu said 'go' */
1421 /* Still using kdb, this processor is in control */
1422 result = kdb_local(reason2, error, regs, db_result);
1423 KDB_DEBUG_STATE("kdb_main_loop 3", result);
1424
1425 if (result == KDB_CMD_CPU)
1426 break;
1427
1428 if (result == KDB_CMD_SS) {
1429 KDB_STATE_SET(DOING_SS);
1430 break;
1431 }
1432
1433 if (result == KDB_CMD_KGDB) {
1434 if (!KDB_STATE(DOING_KGDB))
1435 kdb_printf("Entering please attach debugger "
1436 "or use $D#44+ or $3#33\n");
1437 break;
1438 }
1439 if (result && result != 1 && result != KDB_CMD_GO)
1440 kdb_printf("\nUnexpected kdb_local return code %d\n",
1441 result);
1442 KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1443 break;
1444 }
1445 if (KDB_STATE(DOING_SS))
1446 KDB_STATE_CLEAR(SSBPT);
1447
1448 /* Clean up any keyboard devices before leaving */
1449 kdb_kbd_cleanup_state();
1450
1451 return result;
1452}
1453
1454/*
1455 * kdb_mdr - This function implements the guts of the 'mdr', memory
1456 * read command.
1457 * mdr <addr arg>,<byte count>
1458 * Inputs:
1459 * addr Start address
1460 * count Number of bytes
1461 * Returns:
1462 * Always 0. Any errors are detected and printed by kdb_getarea.
1463 */
1464static int kdb_mdr(unsigned long addr, unsigned int count)
1465{
1466 unsigned char c;
1467 while (count--) {
1468 if (kdb_getarea(c, addr))
1469 return 0;
1470 kdb_printf("%02x", c);
1471 addr++;
1472 }
1473 kdb_printf("\n");
1474 return 0;
1475}
1476
1477/*
1478 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1479 * 'md8' 'mdr' and 'mds' commands.
1480 *
1481 * md|mds [<addr arg> [<line count> [<radix>]]]
1482 * mdWcN [<addr arg> [<line count> [<radix>]]]
1483 * where W = is the width (1, 2, 4 or 8) and N is the count.
1484 * for eg., md1c20 reads 20 bytes, 1 at a time.
1485 * mdr <addr arg>,<byte count>
1486 */
1487static void kdb_md_line(const char *fmtstr, unsigned long addr,
1488 int symbolic, int nosect, int bytesperword,
1489 int num, int repeat, int phys)
1490{
1491 /* print just one line of data */
1492 kdb_symtab_t symtab;
1493 char cbuf[32];
1494 char *c = cbuf;
1495 int i;
1496 int j;
1497 unsigned long word;
1498
1499 memset(cbuf, '\0', sizeof(cbuf));
1500 if (phys)
1501 kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1502 else
1503 kdb_printf(kdb_machreg_fmt0 " ", addr);
1504
1505 for (i = 0; i < num && repeat--; i++) {
1506 if (phys) {
1507 if (kdb_getphysword(&word, addr, bytesperword))
1508 break;
1509 } else if (kdb_getword(&word, addr, bytesperword))
1510 break;
1511 kdb_printf(fmtstr, word);
1512 if (symbolic)
1513 kdbnearsym(word, &symtab);
1514 else
1515 memset(&symtab, 0, sizeof(symtab));
1516 if (symtab.sym_name) {
1517 kdb_symbol_print(word, &symtab, 0);
1518 if (!nosect) {
1519 kdb_printf("\n");
1520 kdb_printf(" %s %s "
1521 kdb_machreg_fmt " "
1522 kdb_machreg_fmt " "
1523 kdb_machreg_fmt, symtab.mod_name,
1524 symtab.sec_name, symtab.sec_start,
1525 symtab.sym_start, symtab.sym_end);
1526 }
1527 addr += bytesperword;
1528 } else {
1529 union {
1530 u64 word;
1531 unsigned char c[8];
1532 } wc;
1533 unsigned char *cp;
1534#ifdef __BIG_ENDIAN
1535 cp = wc.c + 8 - bytesperword;
1536#else
1537 cp = wc.c;
1538#endif
1539 wc.word = word;
1540#define printable_char(c) \
1541 ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1542 for (j = 0; j < bytesperword; j++)
1543 *c++ = printable_char(*cp++);
1544 addr += bytesperword;
1545#undef printable_char
1546 }
1547 }
1548 kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1549 " ", cbuf);
1550}
1551
1552static int kdb_md(int argc, const char **argv)
1553{
1554 static unsigned long last_addr;
1555 static int last_radix, last_bytesperword, last_repeat;
1556 int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1557 int nosect = 0;
1558 char fmtchar, fmtstr[64];
1559 unsigned long addr;
1560 unsigned long word;
1561 long offset = 0;
1562 int symbolic = 0;
1563 int valid = 0;
1564 int phys = 0;
1565 int raw = 0;
1566
1567 kdbgetintenv("MDCOUNT", &mdcount);
1568 kdbgetintenv("RADIX", &radix);
1569 kdbgetintenv("BYTESPERWORD", &bytesperword);
1570
1571 /* Assume 'md <addr>' and start with environment values */
1572 repeat = mdcount * 16 / bytesperword;
1573
1574 if (strcmp(argv[0], "mdr") == 0) {
1575 if (argc == 2 || (argc == 0 && last_addr != 0))
1576 valid = raw = 1;
1577 else
1578 return KDB_ARGCOUNT;
1579 } else if (isdigit(argv[0][2])) {
1580 bytesperword = (int)(argv[0][2] - '0');
1581 if (bytesperword == 0) {
1582 bytesperword = last_bytesperword;
1583 if (bytesperword == 0)
1584 bytesperword = 4;
1585 }
1586 last_bytesperword = bytesperword;
1587 repeat = mdcount * 16 / bytesperword;
1588 if (!argv[0][3])
1589 valid = 1;
1590 else if (argv[0][3] == 'c' && argv[0][4]) {
1591 char *p;
1592 repeat = simple_strtoul(argv[0] + 4, &p, 10);
1593 mdcount = ((repeat * bytesperword) + 15) / 16;
1594 valid = !*p;
1595 }
1596 last_repeat = repeat;
1597 } else if (strcmp(argv[0], "md") == 0)
1598 valid = 1;
1599 else if (strcmp(argv[0], "mds") == 0)
1600 valid = 1;
1601 else if (strcmp(argv[0], "mdp") == 0) {
1602 phys = valid = 1;
1603 }
1604 if (!valid)
1605 return KDB_NOTFOUND;
1606
1607 if (argc == 0) {
1608 if (last_addr == 0)
1609 return KDB_ARGCOUNT;
1610 addr = last_addr;
1611 radix = last_radix;
1612 bytesperword = last_bytesperword;
1613 repeat = last_repeat;
1614 if (raw)
1615 mdcount = repeat;
1616 else
1617 mdcount = ((repeat * bytesperword) + 15) / 16;
1618 }
1619
1620 if (argc) {
1621 unsigned long val;
1622 int diag, nextarg = 1;
1623 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1624 &offset, NULL);
1625 if (diag)
1626 return diag;
1627 if (argc > nextarg+2)
1628 return KDB_ARGCOUNT;
1629
1630 if (argc >= nextarg) {
1631 diag = kdbgetularg(argv[nextarg], &val);
1632 if (!diag) {
1633 mdcount = (int) val;
1634 if (raw)
1635 repeat = mdcount;
1636 else
1637 repeat = mdcount * 16 / bytesperword;
1638 }
1639 }
1640 if (argc >= nextarg+1) {
1641 diag = kdbgetularg(argv[nextarg+1], &val);
1642 if (!diag)
1643 radix = (int) val;
1644 }
1645 }
1646
1647 if (strcmp(argv[0], "mdr") == 0) {
1648 int ret;
1649 last_addr = addr;
1650 ret = kdb_mdr(addr, mdcount);
1651 last_addr += mdcount;
1652 last_repeat = mdcount;
1653 last_bytesperword = bytesperword; // to make REPEAT happy
1654 return ret;
1655 }
1656
1657 switch (radix) {
1658 case 10:
1659 fmtchar = 'd';
1660 break;
1661 case 16:
1662 fmtchar = 'x';
1663 break;
1664 case 8:
1665 fmtchar = 'o';
1666 break;
1667 default:
1668 return KDB_BADRADIX;
1669 }
1670
1671 last_radix = radix;
1672
1673 if (bytesperword > KDB_WORD_SIZE)
1674 return KDB_BADWIDTH;
1675
1676 switch (bytesperword) {
1677 case 8:
1678 sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1679 break;
1680 case 4:
1681 sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1682 break;
1683 case 2:
1684 sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1685 break;
1686 case 1:
1687 sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1688 break;
1689 default:
1690 return KDB_BADWIDTH;
1691 }
1692
1693 last_repeat = repeat;
1694 last_bytesperword = bytesperword;
1695
1696 if (strcmp(argv[0], "mds") == 0) {
1697 symbolic = 1;
1698 /* Do not save these changes as last_*, they are temporary mds
1699 * overrides.
1700 */
1701 bytesperword = KDB_WORD_SIZE;
1702 repeat = mdcount;
1703 kdbgetintenv("NOSECT", &nosect);
1704 }
1705
1706 /* Round address down modulo BYTESPERWORD */
1707
1708 addr &= ~(bytesperword-1);
1709
1710 while (repeat > 0) {
1711 unsigned long a;
1712 int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1713
1714 if (KDB_FLAG(CMD_INTERRUPT))
1715 return 0;
1716 for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1717 if (phys) {
1718 if (kdb_getphysword(&word, a, bytesperword)
1719 || word)
1720 break;
1721 } else if (kdb_getword(&word, a, bytesperword) || word)
1722 break;
1723 }
1724 n = min(num, repeat);
1725 kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1726 num, repeat, phys);
1727 addr += bytesperword * n;
1728 repeat -= n;
1729 z = (z + num - 1) / num;
1730 if (z > 2) {
1731 int s = num * (z-2);
1732 kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1733 " zero suppressed\n",
1734 addr, addr + bytesperword * s - 1);
1735 addr += bytesperword * s;
1736 repeat -= s;
1737 }
1738 }
1739 last_addr = addr;
1740
1741 return 0;
1742}
1743
1744/*
1745 * kdb_mm - This function implements the 'mm' command.
1746 * mm address-expression new-value
1747 * Remarks:
1748 * mm works on machine words, mmW works on bytes.
1749 */
1750static int kdb_mm(int argc, const char **argv)
1751{
1752 int diag;
1753 unsigned long addr;
1754 long offset = 0;
1755 unsigned long contents;
1756 int nextarg;
1757 int width;
1758
1759 if (argv[0][2] && !isdigit(argv[0][2]))
1760 return KDB_NOTFOUND;
1761
1762 if (argc < 2)
1763 return KDB_ARGCOUNT;
1764
1765 nextarg = 1;
1766 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1767 if (diag)
1768 return diag;
1769
1770 if (nextarg > argc)
1771 return KDB_ARGCOUNT;
1772 diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1773 if (diag)
1774 return diag;
1775
1776 if (nextarg != argc + 1)
1777 return KDB_ARGCOUNT;
1778
1779 width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1780 diag = kdb_putword(addr, contents, width);
1781 if (diag)
1782 return diag;
1783
1784 kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1785
1786 return 0;
1787}
1788
1789/*
1790 * kdb_go - This function implements the 'go' command.
1791 * go [address-expression]
1792 */
1793static int kdb_go(int argc, const char **argv)
1794{
1795 unsigned long addr;
1796 int diag;
1797 int nextarg;
1798 long offset;
1799
1800 if (raw_smp_processor_id() != kdb_initial_cpu) {
1801 kdb_printf("go must execute on the entry cpu, "
1802 "please use \"cpu %d\" and then execute go\n",
1803 kdb_initial_cpu);
1804 return KDB_BADCPUNUM;
1805 }
1806 if (argc == 1) {
1807 nextarg = 1;
1808 diag = kdbgetaddrarg(argc, argv, &nextarg,
1809 &addr, &offset, NULL);
1810 if (diag)
1811 return diag;
1812 } else if (argc) {
1813 return KDB_ARGCOUNT;
1814 }
1815
1816 diag = KDB_CMD_GO;
1817 if (KDB_FLAG(CATASTROPHIC)) {
1818 kdb_printf("Catastrophic error detected\n");
1819 kdb_printf("kdb_continue_catastrophic=%d, ",
1820 kdb_continue_catastrophic);
1821 if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1822 kdb_printf("type go a second time if you really want "
1823 "to continue\n");
1824 return 0;
1825 }
1826 if (kdb_continue_catastrophic == 2) {
1827 kdb_printf("forcing reboot\n");
1828 kdb_reboot(0, NULL);
1829 }
1830 kdb_printf("attempting to continue\n");
1831 }
1832 return diag;
1833}
1834
1835/*
1836 * kdb_rd - This function implements the 'rd' command.
1837 */
1838static int kdb_rd(int argc, const char **argv)
1839{
1840 int len = kdb_check_regs();
1841#if DBG_MAX_REG_NUM > 0
1842 int i;
1843 char *rname;
1844 int rsize;
1845 u64 reg64;
1846 u32 reg32;
1847 u16 reg16;
1848 u8 reg8;
1849
1850 if (len)
1851 return len;
1852
1853 for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1854 rsize = dbg_reg_def[i].size * 2;
1855 if (rsize > 16)
1856 rsize = 2;
1857 if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1858 len = 0;
1859 kdb_printf("\n");
1860 }
1861 if (len)
1862 len += kdb_printf(" ");
1863 switch(dbg_reg_def[i].size * 8) {
1864 case 8:
1865 rname = dbg_get_reg(i, ®8, kdb_current_regs);
1866 if (!rname)
1867 break;
1868 len += kdb_printf("%s: %02x", rname, reg8);
1869 break;
1870 case 16:
1871 rname = dbg_get_reg(i, ®16, kdb_current_regs);
1872 if (!rname)
1873 break;
1874 len += kdb_printf("%s: %04x", rname, reg16);
1875 break;
1876 case 32:
1877 rname = dbg_get_reg(i, ®32, kdb_current_regs);
1878 if (!rname)
1879 break;
1880 len += kdb_printf("%s: %08x", rname, reg32);
1881 break;
1882 case 64:
1883 rname = dbg_get_reg(i, ®64, kdb_current_regs);
1884 if (!rname)
1885 break;
1886 len += kdb_printf("%s: %016llx", rname, reg64);
1887 break;
1888 default:
1889 len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1890 }
1891 }
1892 kdb_printf("\n");
1893#else
1894 if (len)
1895 return len;
1896
1897 kdb_dumpregs(kdb_current_regs);
1898#endif
1899 return 0;
1900}
1901
1902/*
1903 * kdb_rm - This function implements the 'rm' (register modify) command.
1904 * rm register-name new-contents
1905 * Remarks:
1906 * Allows register modification with the same restrictions as gdb
1907 */
1908static int kdb_rm(int argc, const char **argv)
1909{
1910#if DBG_MAX_REG_NUM > 0
1911 int diag;
1912 const char *rname;
1913 int i;
1914 u64 reg64;
1915 u32 reg32;
1916 u16 reg16;
1917 u8 reg8;
1918
1919 if (argc != 2)
1920 return KDB_ARGCOUNT;
1921 /*
1922 * Allow presence or absence of leading '%' symbol.
1923 */
1924 rname = argv[1];
1925 if (*rname == '%')
1926 rname++;
1927
1928 diag = kdbgetu64arg(argv[2], ®64);
1929 if (diag)
1930 return diag;
1931
1932 diag = kdb_check_regs();
1933 if (diag)
1934 return diag;
1935
1936 diag = KDB_BADREG;
1937 for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1938 if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1939 diag = 0;
1940 break;
1941 }
1942 }
1943 if (!diag) {
1944 switch(dbg_reg_def[i].size * 8) {
1945 case 8:
1946 reg8 = reg64;
1947 dbg_set_reg(i, ®8, kdb_current_regs);
1948 break;
1949 case 16:
1950 reg16 = reg64;
1951 dbg_set_reg(i, ®16, kdb_current_regs);
1952 break;
1953 case 32:
1954 reg32 = reg64;
1955 dbg_set_reg(i, ®32, kdb_current_regs);
1956 break;
1957 case 64:
1958 dbg_set_reg(i, ®64, kdb_current_regs);
1959 break;
1960 }
1961 }
1962 return diag;
1963#else
1964 kdb_printf("ERROR: Register set currently not implemented\n");
1965 return 0;
1966#endif
1967}
1968
1969#if defined(CONFIG_MAGIC_SYSRQ)
1970/*
1971 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1972 * which interfaces to the soi-disant MAGIC SYSRQ functionality.
1973 * sr <magic-sysrq-code>
1974 */
1975static int kdb_sr(int argc, const char **argv)
1976{
1977 bool check_mask =
1978 !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1979
1980 if (argc != 1)
1981 return KDB_ARGCOUNT;
1982
1983 kdb_trap_printk++;
1984 __handle_sysrq(*argv[1], check_mask);
1985 kdb_trap_printk--;
1986
1987 return 0;
1988}
1989#endif /* CONFIG_MAGIC_SYSRQ */
1990
1991/*
1992 * kdb_ef - This function implements the 'regs' (display exception
1993 * frame) command. This command takes an address and expects to
1994 * find an exception frame at that address, formats and prints
1995 * it.
1996 * regs address-expression
1997 * Remarks:
1998 * Not done yet.
1999 */
2000static int kdb_ef(int argc, const char **argv)
2001{
2002 int diag;
2003 unsigned long addr;
2004 long offset;
2005 int nextarg;
2006
2007 if (argc != 1)
2008 return KDB_ARGCOUNT;
2009
2010 nextarg = 1;
2011 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2012 if (diag)
2013 return diag;
2014 show_regs((struct pt_regs *)addr);
2015 return 0;
2016}
2017
2018#if defined(CONFIG_MODULES)
2019/*
2020 * kdb_lsmod - This function implements the 'lsmod' command. Lists
2021 * currently loaded kernel modules.
2022 * Mostly taken from userland lsmod.
2023 */
2024static int kdb_lsmod(int argc, const char **argv)
2025{
2026 struct module *mod;
2027
2028 if (argc != 0)
2029 return KDB_ARGCOUNT;
2030
2031 kdb_printf("Module Size modstruct Used by\n");
2032 list_for_each_entry(mod, kdb_modules, list) {
2033 if (mod->state == MODULE_STATE_UNFORMED)
2034 continue;
2035
2036 kdb_printf("%-20s%8u 0x%px ", mod->name,
2037 mod->core_layout.size, (void *)mod);
2038#ifdef CONFIG_MODULE_UNLOAD
2039 kdb_printf("%4d ", module_refcount(mod));
2040#endif
2041 if (mod->state == MODULE_STATE_GOING)
2042 kdb_printf(" (Unloading)");
2043 else if (mod->state == MODULE_STATE_COMING)
2044 kdb_printf(" (Loading)");
2045 else
2046 kdb_printf(" (Live)");
2047 kdb_printf(" 0x%px", mod->core_layout.base);
2048
2049#ifdef CONFIG_MODULE_UNLOAD
2050 {
2051 struct module_use *use;
2052 kdb_printf(" [ ");
2053 list_for_each_entry(use, &mod->source_list,
2054 source_list)
2055 kdb_printf("%s ", use->target->name);
2056 kdb_printf("]\n");
2057 }
2058#endif
2059 }
2060
2061 return 0;
2062}
2063
2064#endif /* CONFIG_MODULES */
2065
2066/*
2067 * kdb_env - This function implements the 'env' command. Display the
2068 * current environment variables.
2069 */
2070
2071static int kdb_env(int argc, const char **argv)
2072{
2073 int i;
2074
2075 for (i = 0; i < __nenv; i++) {
2076 if (__env[i])
2077 kdb_printf("%s\n", __env[i]);
2078 }
2079
2080 if (KDB_DEBUG(MASK))
2081 kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
2082
2083 return 0;
2084}
2085
2086#ifdef CONFIG_PRINTK
2087/*
2088 * kdb_dmesg - This function implements the 'dmesg' command to display
2089 * the contents of the syslog buffer.
2090 * dmesg [lines] [adjust]
2091 */
2092static int kdb_dmesg(int argc, const char **argv)
2093{
2094 int diag;
2095 int logging;
2096 int lines = 0;
2097 int adjust = 0;
2098 int n = 0;
2099 int skip = 0;
2100 struct kmsg_dumper dumper = { .active = 1 };
2101 size_t len;
2102 char buf[201];
2103
2104 if (argc > 2)
2105 return KDB_ARGCOUNT;
2106 if (argc) {
2107 char *cp;
2108 lines = simple_strtol(argv[1], &cp, 0);
2109 if (*cp)
2110 lines = 0;
2111 if (argc > 1) {
2112 adjust = simple_strtoul(argv[2], &cp, 0);
2113 if (*cp || adjust < 0)
2114 adjust = 0;
2115 }
2116 }
2117
2118 /* disable LOGGING if set */
2119 diag = kdbgetintenv("LOGGING", &logging);
2120 if (!diag && logging) {
2121 const char *setargs[] = { "set", "LOGGING", "0" };
2122 kdb_set(2, setargs);
2123 }
2124
2125 kmsg_dump_rewind_nolock(&dumper);
2126 while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
2127 n++;
2128
2129 if (lines < 0) {
2130 if (adjust >= n)
2131 kdb_printf("buffer only contains %d lines, nothing "
2132 "printed\n", n);
2133 else if (adjust - lines >= n)
2134 kdb_printf("buffer only contains %d lines, last %d "
2135 "lines printed\n", n, n - adjust);
2136 skip = adjust;
2137 lines = abs(lines);
2138 } else if (lines > 0) {
2139 skip = n - lines - adjust;
2140 lines = abs(lines);
2141 if (adjust >= n) {
2142 kdb_printf("buffer only contains %d lines, "
2143 "nothing printed\n", n);
2144 skip = n;
2145 } else if (skip < 0) {
2146 lines += skip;
2147 skip = 0;
2148 kdb_printf("buffer only contains %d lines, first "
2149 "%d lines printed\n", n, lines);
2150 }
2151 } else {
2152 lines = n;
2153 }
2154
2155 if (skip >= n || skip < 0)
2156 return 0;
2157
2158 kmsg_dump_rewind_nolock(&dumper);
2159 while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
2160 if (skip) {
2161 skip--;
2162 continue;
2163 }
2164 if (!lines--)
2165 break;
2166 if (KDB_FLAG(CMD_INTERRUPT))
2167 return 0;
2168
2169 kdb_printf("%.*s\n", (int)len - 1, buf);
2170 }
2171
2172 return 0;
2173}
2174#endif /* CONFIG_PRINTK */
2175
2176/* Make sure we balance enable/disable calls, must disable first. */
2177static atomic_t kdb_nmi_disabled;
2178
2179static int kdb_disable_nmi(int argc, const char *argv[])
2180{
2181 if (atomic_read(&kdb_nmi_disabled))
2182 return 0;
2183 atomic_set(&kdb_nmi_disabled, 1);
2184 arch_kgdb_ops.enable_nmi(0);
2185 return 0;
2186}
2187
2188static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2189{
2190 if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2191 return -EINVAL;
2192 arch_kgdb_ops.enable_nmi(1);
2193 return 0;
2194}
2195
2196static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2197 .set = kdb_param_enable_nmi,
2198};
2199module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2200
2201/*
2202 * kdb_cpu - This function implements the 'cpu' command.
2203 * cpu [<cpunum>]
2204 * Returns:
2205 * KDB_CMD_CPU for success, a kdb diagnostic if error
2206 */
2207static void kdb_cpu_status(void)
2208{
2209 int i, start_cpu, first_print = 1;
2210 char state, prev_state = '?';
2211
2212 kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2213 kdb_printf("Available cpus: ");
2214 for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2215 if (!cpu_online(i)) {
2216 state = 'F'; /* cpu is offline */
2217 } else if (!kgdb_info[i].enter_kgdb) {
2218 state = 'D'; /* cpu is online but unresponsive */
2219 } else {
2220 state = ' '; /* cpu is responding to kdb */
2221 if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2222 state = 'I'; /* idle task */
2223 }
2224 if (state != prev_state) {
2225 if (prev_state != '?') {
2226 if (!first_print)
2227 kdb_printf(", ");
2228 first_print = 0;
2229 kdb_printf("%d", start_cpu);
2230 if (start_cpu < i-1)
2231 kdb_printf("-%d", i-1);
2232 if (prev_state != ' ')
2233 kdb_printf("(%c)", prev_state);
2234 }
2235 prev_state = state;
2236 start_cpu = i;
2237 }
2238 }
2239 /* print the trailing cpus, ignoring them if they are all offline */
2240 if (prev_state != 'F') {
2241 if (!first_print)
2242 kdb_printf(", ");
2243 kdb_printf("%d", start_cpu);
2244 if (start_cpu < i-1)
2245 kdb_printf("-%d", i-1);
2246 if (prev_state != ' ')
2247 kdb_printf("(%c)", prev_state);
2248 }
2249 kdb_printf("\n");
2250}
2251
2252static int kdb_cpu(int argc, const char **argv)
2253{
2254 unsigned long cpunum;
2255 int diag;
2256
2257 if (argc == 0) {
2258 kdb_cpu_status();
2259 return 0;
2260 }
2261
2262 if (argc != 1)
2263 return KDB_ARGCOUNT;
2264
2265 diag = kdbgetularg(argv[1], &cpunum);
2266 if (diag)
2267 return diag;
2268
2269 /*
2270 * Validate cpunum
2271 */
2272 if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2273 return KDB_BADCPUNUM;
2274
2275 dbg_switch_cpu = cpunum;
2276
2277 /*
2278 * Switch to other cpu
2279 */
2280 return KDB_CMD_CPU;
2281}
2282
2283/* The user may not realize that ps/bta with no parameters does not print idle
2284 * or sleeping system daemon processes, so tell them how many were suppressed.
2285 */
2286void kdb_ps_suppressed(void)
2287{
2288 int idle = 0, daemon = 0;
2289 unsigned long mask_I = kdb_task_state_string("I"),
2290 mask_M = kdb_task_state_string("M");
2291 unsigned long cpu;
2292 const struct task_struct *p, *g;
2293 for_each_online_cpu(cpu) {
2294 p = kdb_curr_task(cpu);
2295 if (kdb_task_state(p, mask_I))
2296 ++idle;
2297 }
2298 kdb_do_each_thread(g, p) {
2299 if (kdb_task_state(p, mask_M))
2300 ++daemon;
2301 } kdb_while_each_thread(g, p);
2302 if (idle || daemon) {
2303 if (idle)
2304 kdb_printf("%d idle process%s (state I)%s\n",
2305 idle, idle == 1 ? "" : "es",
2306 daemon ? " and " : "");
2307 if (daemon)
2308 kdb_printf("%d sleeping system daemon (state M) "
2309 "process%s", daemon,
2310 daemon == 1 ? "" : "es");
2311 kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2312 }
2313}
2314
2315/*
2316 * kdb_ps - This function implements the 'ps' command which shows a
2317 * list of the active processes.
2318 * ps [DRSTCZEUIMA] All processes, optionally filtered by state
2319 */
2320void kdb_ps1(const struct task_struct *p)
2321{
2322 int cpu;
2323 unsigned long tmp;
2324
2325 if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
2326 return;
2327
2328 cpu = kdb_process_cpu(p);
2329 kdb_printf("0x%px %8d %8d %d %4d %c 0x%px %c%s\n",
2330 (void *)p, p->pid, p->parent->pid,
2331 kdb_task_has_cpu(p), kdb_process_cpu(p),
2332 kdb_task_state_char(p),
2333 (void *)(&p->thread),
2334 p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2335 p->comm);
2336 if (kdb_task_has_cpu(p)) {
2337 if (!KDB_TSK(cpu)) {
2338 kdb_printf(" Error: no saved data for this cpu\n");
2339 } else {
2340 if (KDB_TSK(cpu) != p)
2341 kdb_printf(" Error: does not match running "
2342 "process table (0x%px)\n", KDB_TSK(cpu));
2343 }
2344 }
2345}
2346
2347static int kdb_ps(int argc, const char **argv)
2348{
2349 struct task_struct *g, *p;
2350 unsigned long mask, cpu;
2351
2352 if (argc == 0)
2353 kdb_ps_suppressed();
2354 kdb_printf("%-*s Pid Parent [*] cpu State %-*s Command\n",
2355 (int)(2*sizeof(void *))+2, "Task Addr",
2356 (int)(2*sizeof(void *))+2, "Thread");
2357 mask = kdb_task_state_string(argc ? argv[1] : NULL);
2358 /* Run the active tasks first */
2359 for_each_online_cpu(cpu) {
2360 if (KDB_FLAG(CMD_INTERRUPT))
2361 return 0;
2362 p = kdb_curr_task(cpu);
2363 if (kdb_task_state(p, mask))
2364 kdb_ps1(p);
2365 }
2366 kdb_printf("\n");
2367 /* Now the real tasks */
2368 kdb_do_each_thread(g, p) {
2369 if (KDB_FLAG(CMD_INTERRUPT))
2370 return 0;
2371 if (kdb_task_state(p, mask))
2372 kdb_ps1(p);
2373 } kdb_while_each_thread(g, p);
2374
2375 return 0;
2376}
2377
2378/*
2379 * kdb_pid - This function implements the 'pid' command which switches
2380 * the currently active process.
2381 * pid [<pid> | R]
2382 */
2383static int kdb_pid(int argc, const char **argv)
2384{
2385 struct task_struct *p;
2386 unsigned long val;
2387 int diag;
2388
2389 if (argc > 1)
2390 return KDB_ARGCOUNT;
2391
2392 if (argc) {
2393 if (strcmp(argv[1], "R") == 0) {
2394 p = KDB_TSK(kdb_initial_cpu);
2395 } else {
2396 diag = kdbgetularg(argv[1], &val);
2397 if (diag)
2398 return KDB_BADINT;
2399
2400 p = find_task_by_pid_ns((pid_t)val, &init_pid_ns);
2401 if (!p) {
2402 kdb_printf("No task with pid=%d\n", (pid_t)val);
2403 return 0;
2404 }
2405 }
2406 kdb_set_current_task(p);
2407 }
2408 kdb_printf("KDB current process is %s(pid=%d)\n",
2409 kdb_current_task->comm,
2410 kdb_current_task->pid);
2411
2412 return 0;
2413}
2414
2415static int kdb_kgdb(int argc, const char **argv)
2416{
2417 return KDB_CMD_KGDB;
2418}
2419
2420/*
2421 * kdb_help - This function implements the 'help' and '?' commands.
2422 */
2423static int kdb_help(int argc, const char **argv)
2424{
2425 kdbtab_t *kt;
2426 int i;
2427
2428 kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2429 kdb_printf("-----------------------------"
2430 "-----------------------------\n");
2431 for_each_kdbcmd(kt, i) {
2432 char *space = "";
2433 if (KDB_FLAG(CMD_INTERRUPT))
2434 return 0;
2435 if (!kt->cmd_name)
2436 continue;
2437 if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2438 continue;
2439 if (strlen(kt->cmd_usage) > 20)
2440 space = "\n ";
2441 kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2442 kt->cmd_usage, space, kt->cmd_help);
2443 }
2444 return 0;
2445}
2446
2447/*
2448 * kdb_kill - This function implements the 'kill' commands.
2449 */
2450static int kdb_kill(int argc, const char **argv)
2451{
2452 long sig, pid;
2453 char *endp;
2454 struct task_struct *p;
2455
2456 if (argc != 2)
2457 return KDB_ARGCOUNT;
2458
2459 sig = simple_strtol(argv[1], &endp, 0);
2460 if (*endp)
2461 return KDB_BADINT;
2462 if ((sig >= 0) || !valid_signal(-sig)) {
2463 kdb_printf("Invalid signal parameter.<-signal>\n");
2464 return 0;
2465 }
2466 sig = -sig;
2467
2468 pid = simple_strtol(argv[2], &endp, 0);
2469 if (*endp)
2470 return KDB_BADINT;
2471 if (pid <= 0) {
2472 kdb_printf("Process ID must be large than 0.\n");
2473 return 0;
2474 }
2475
2476 /* Find the process. */
2477 p = find_task_by_pid_ns(pid, &init_pid_ns);
2478 if (!p) {
2479 kdb_printf("The specified process isn't found.\n");
2480 return 0;
2481 }
2482 p = p->group_leader;
2483 kdb_send_sig(p, sig);
2484 return 0;
2485}
2486
2487/*
2488 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2489 * I cannot call that code directly from kdb, it has an unconditional
2490 * cli()/sti() and calls routines that take locks which can stop the debugger.
2491 */
2492static void kdb_sysinfo(struct sysinfo *val)
2493{
2494 u64 uptime = ktime_get_mono_fast_ns();
2495
2496 memset(val, 0, sizeof(*val));
2497 val->uptime = div_u64(uptime, NSEC_PER_SEC);
2498 val->loads[0] = avenrun[0];
2499 val->loads[1] = avenrun[1];
2500 val->loads[2] = avenrun[2];
2501 val->procs = nr_threads-1;
2502 si_meminfo(val);
2503
2504 return;
2505}
2506
2507/*
2508 * kdb_summary - This function implements the 'summary' command.
2509 */
2510static int kdb_summary(int argc, const char **argv)
2511{
2512 time64_t now;
2513 struct tm tm;
2514 struct sysinfo val;
2515
2516 if (argc)
2517 return KDB_ARGCOUNT;
2518
2519 kdb_printf("sysname %s\n", init_uts_ns.name.sysname);
2520 kdb_printf("release %s\n", init_uts_ns.name.release);
2521 kdb_printf("version %s\n", init_uts_ns.name.version);
2522 kdb_printf("machine %s\n", init_uts_ns.name.machine);
2523 kdb_printf("nodename %s\n", init_uts_ns.name.nodename);
2524 kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2525
2526 now = __ktime_get_real_seconds();
2527 time64_to_tm(now, 0, &tm);
2528 kdb_printf("date %04ld-%02d-%02d %02d:%02d:%02d "
2529 "tz_minuteswest %d\n",
2530 1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2531 tm.tm_hour, tm.tm_min, tm.tm_sec,
2532 sys_tz.tz_minuteswest);
2533
2534 kdb_sysinfo(&val);
2535 kdb_printf("uptime ");
2536 if (val.uptime > (24*60*60)) {
2537 int days = val.uptime / (24*60*60);
2538 val.uptime %= (24*60*60);
2539 kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2540 }
2541 kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2542
2543 kdb_printf("load avg %ld.%02ld %ld.%02ld %ld.%02ld\n",
2544 LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2545 LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2546 LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2547
2548 /* Display in kilobytes */
2549#define K(x) ((x) << (PAGE_SHIFT - 10))
2550 kdb_printf("\nMemTotal: %8lu kB\nMemFree: %8lu kB\n"
2551 "Buffers: %8lu kB\n",
2552 K(val.totalram), K(val.freeram), K(val.bufferram));
2553 return 0;
2554}
2555
2556/*
2557 * kdb_per_cpu - This function implements the 'per_cpu' command.
2558 */
2559static int kdb_per_cpu(int argc, const char **argv)
2560{
2561 char fmtstr[64];
2562 int cpu, diag, nextarg = 1;
2563 unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2564
2565 if (argc < 1 || argc > 3)
2566 return KDB_ARGCOUNT;
2567
2568 diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2569 if (diag)
2570 return diag;
2571
2572 if (argc >= 2) {
2573 diag = kdbgetularg(argv[2], &bytesperword);
2574 if (diag)
2575 return diag;
2576 }
2577 if (!bytesperword)
2578 bytesperword = KDB_WORD_SIZE;
2579 else if (bytesperword > KDB_WORD_SIZE)
2580 return KDB_BADWIDTH;
2581 sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2582 if (argc >= 3) {
2583 diag = kdbgetularg(argv[3], &whichcpu);
2584 if (diag)
2585 return diag;
2586 if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2587 kdb_printf("cpu %ld is not online\n", whichcpu);
2588 return KDB_BADCPUNUM;
2589 }
2590 }
2591
2592 /* Most architectures use __per_cpu_offset[cpu], some use
2593 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2594 */
2595#ifdef __per_cpu_offset
2596#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2597#else
2598#ifdef CONFIG_SMP
2599#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2600#else
2601#define KDB_PCU(cpu) 0
2602#endif
2603#endif
2604 for_each_online_cpu(cpu) {
2605 if (KDB_FLAG(CMD_INTERRUPT))
2606 return 0;
2607
2608 if (whichcpu != ~0UL && whichcpu != cpu)
2609 continue;
2610 addr = symaddr + KDB_PCU(cpu);
2611 diag = kdb_getword(&val, addr, bytesperword);
2612 if (diag) {
2613 kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2614 "read, diag=%d\n", cpu, addr, diag);
2615 continue;
2616 }
2617 kdb_printf("%5d ", cpu);
2618 kdb_md_line(fmtstr, addr,
2619 bytesperword == KDB_WORD_SIZE,
2620 1, bytesperword, 1, 1, 0);
2621 }
2622#undef KDB_PCU
2623 return 0;
2624}
2625
2626/*
2627 * display help for the use of cmd | grep pattern
2628 */
2629static int kdb_grep_help(int argc, const char **argv)
2630{
2631 kdb_printf("Usage of cmd args | grep pattern:\n");
2632 kdb_printf(" Any command's output may be filtered through an ");
2633 kdb_printf("emulated 'pipe'.\n");
2634 kdb_printf(" 'grep' is just a key word.\n");
2635 kdb_printf(" The pattern may include a very limited set of "
2636 "metacharacters:\n");
2637 kdb_printf(" pattern or ^pattern or pattern$ or ^pattern$\n");
2638 kdb_printf(" And if there are spaces in the pattern, you may "
2639 "quote it:\n");
2640 kdb_printf(" \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2641 " or \"^pat tern$\"\n");
2642 return 0;
2643}
2644
2645/*
2646 * kdb_register_flags - This function is used to register a kernel
2647 * debugger command.
2648 * Inputs:
2649 * cmd Command name
2650 * func Function to execute the command
2651 * usage A simple usage string showing arguments
2652 * help A simple help string describing command
2653 * repeat Does the command auto repeat on enter?
2654 * Returns:
2655 * zero for success, one if a duplicate command.
2656 */
2657#define kdb_command_extend 50 /* arbitrary */
2658int kdb_register_flags(char *cmd,
2659 kdb_func_t func,
2660 char *usage,
2661 char *help,
2662 short minlen,
2663 kdb_cmdflags_t flags)
2664{
2665 int i;
2666 kdbtab_t *kp;
2667
2668 /*
2669 * Brute force method to determine duplicates
2670 */
2671 for_each_kdbcmd(kp, i) {
2672 if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2673 kdb_printf("Duplicate kdb command registered: "
2674 "%s, func %px help %s\n", cmd, func, help);
2675 return 1;
2676 }
2677 }
2678
2679 /*
2680 * Insert command into first available location in table
2681 */
2682 for_each_kdbcmd(kp, i) {
2683 if (kp->cmd_name == NULL)
2684 break;
2685 }
2686
2687 if (i >= kdb_max_commands) {
2688 kdbtab_t *new = kmalloc_array(kdb_max_commands -
2689 KDB_BASE_CMD_MAX +
2690 kdb_command_extend,
2691 sizeof(*new),
2692 GFP_KDB);
2693 if (!new) {
2694 kdb_printf("Could not allocate new kdb_command "
2695 "table\n");
2696 return 1;
2697 }
2698 if (kdb_commands) {
2699 memcpy(new, kdb_commands,
2700 (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new));
2701 kfree(kdb_commands);
2702 }
2703 memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0,
2704 kdb_command_extend * sizeof(*new));
2705 kdb_commands = new;
2706 kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX;
2707 kdb_max_commands += kdb_command_extend;
2708 }
2709
2710 kp->cmd_name = cmd;
2711 kp->cmd_func = func;
2712 kp->cmd_usage = usage;
2713 kp->cmd_help = help;
2714 kp->cmd_minlen = minlen;
2715 kp->cmd_flags = flags;
2716
2717 return 0;
2718}
2719EXPORT_SYMBOL_GPL(kdb_register_flags);
2720
2721
2722/*
2723 * kdb_register - Compatibility register function for commands that do
2724 * not need to specify a repeat state. Equivalent to
2725 * kdb_register_flags with flags set to 0.
2726 * Inputs:
2727 * cmd Command name
2728 * func Function to execute the command
2729 * usage A simple usage string showing arguments
2730 * help A simple help string describing command
2731 * Returns:
2732 * zero for success, one if a duplicate command.
2733 */
2734int kdb_register(char *cmd,
2735 kdb_func_t func,
2736 char *usage,
2737 char *help,
2738 short minlen)
2739{
2740 return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2741}
2742EXPORT_SYMBOL_GPL(kdb_register);
2743
2744/*
2745 * kdb_unregister - This function is used to unregister a kernel
2746 * debugger command. It is generally called when a module which
2747 * implements kdb commands is unloaded.
2748 * Inputs:
2749 * cmd Command name
2750 * Returns:
2751 * zero for success, one command not registered.
2752 */
2753int kdb_unregister(char *cmd)
2754{
2755 int i;
2756 kdbtab_t *kp;
2757
2758 /*
2759 * find the command.
2760 */
2761 for_each_kdbcmd(kp, i) {
2762 if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2763 kp->cmd_name = NULL;
2764 return 0;
2765 }
2766 }
2767
2768 /* Couldn't find it. */
2769 return 1;
2770}
2771EXPORT_SYMBOL_GPL(kdb_unregister);
2772
2773/* Initialize the kdb command table. */
2774static void __init kdb_inittab(void)
2775{
2776 int i;
2777 kdbtab_t *kp;
2778
2779 for_each_kdbcmd(kp, i)
2780 kp->cmd_name = NULL;
2781
2782 kdb_register_flags("md", kdb_md, "<vaddr>",
2783 "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2784 KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2785 kdb_register_flags("mdr", kdb_md, "<vaddr> <bytes>",
2786 "Display Raw Memory", 0,
2787 KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2788 kdb_register_flags("mdp", kdb_md, "<paddr> <bytes>",
2789 "Display Physical Memory", 0,
2790 KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2791 kdb_register_flags("mds", kdb_md, "<vaddr>",
2792 "Display Memory Symbolically", 0,
2793 KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2794 kdb_register_flags("mm", kdb_mm, "<vaddr> <contents>",
2795 "Modify Memory Contents", 0,
2796 KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS);
2797 kdb_register_flags("go", kdb_go, "[<vaddr>]",
2798 "Continue Execution", 1,
2799 KDB_ENABLE_REG_WRITE | KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2800 kdb_register_flags("rd", kdb_rd, "",
2801 "Display Registers", 0,
2802 KDB_ENABLE_REG_READ);
2803 kdb_register_flags("rm", kdb_rm, "<reg> <contents>",
2804 "Modify Registers", 0,
2805 KDB_ENABLE_REG_WRITE);
2806 kdb_register_flags("ef", kdb_ef, "<vaddr>",
2807 "Display exception frame", 0,
2808 KDB_ENABLE_MEM_READ);
2809 kdb_register_flags("bt", kdb_bt, "[<vaddr>]",
2810 "Stack traceback", 1,
2811 KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2812 kdb_register_flags("btp", kdb_bt, "<pid>",
2813 "Display stack for process <pid>", 0,
2814 KDB_ENABLE_INSPECT);
2815 kdb_register_flags("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
2816 "Backtrace all processes matching state flag", 0,
2817 KDB_ENABLE_INSPECT);
2818 kdb_register_flags("btc", kdb_bt, "",
2819 "Backtrace current process on each cpu", 0,
2820 KDB_ENABLE_INSPECT);
2821 kdb_register_flags("btt", kdb_bt, "<vaddr>",
2822 "Backtrace process given its struct task address", 0,
2823 KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2824 kdb_register_flags("env", kdb_env, "",
2825 "Show environment variables", 0,
2826 KDB_ENABLE_ALWAYS_SAFE);
2827 kdb_register_flags("set", kdb_set, "",
2828 "Set environment variables", 0,
2829 KDB_ENABLE_ALWAYS_SAFE);
2830 kdb_register_flags("help", kdb_help, "",
2831 "Display Help Message", 1,
2832 KDB_ENABLE_ALWAYS_SAFE);
2833 kdb_register_flags("?", kdb_help, "",
2834 "Display Help Message", 0,
2835 KDB_ENABLE_ALWAYS_SAFE);
2836 kdb_register_flags("cpu", kdb_cpu, "<cpunum>",
2837 "Switch to new cpu", 0,
2838 KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2839 kdb_register_flags("kgdb", kdb_kgdb, "",
2840 "Enter kgdb mode", 0, 0);
2841 kdb_register_flags("ps", kdb_ps, "[<flags>|A]",
2842 "Display active task list", 0,
2843 KDB_ENABLE_INSPECT);
2844 kdb_register_flags("pid", kdb_pid, "<pidnum>",
2845 "Switch to another task", 0,
2846 KDB_ENABLE_INSPECT);
2847 kdb_register_flags("reboot", kdb_reboot, "",
2848 "Reboot the machine immediately", 0,
2849 KDB_ENABLE_REBOOT);
2850#if defined(CONFIG_MODULES)
2851 kdb_register_flags("lsmod", kdb_lsmod, "",
2852 "List loaded kernel modules", 0,
2853 KDB_ENABLE_INSPECT);
2854#endif
2855#if defined(CONFIG_MAGIC_SYSRQ)
2856 kdb_register_flags("sr", kdb_sr, "<key>",
2857 "Magic SysRq key", 0,
2858 KDB_ENABLE_ALWAYS_SAFE);
2859#endif
2860#if defined(CONFIG_PRINTK)
2861 kdb_register_flags("dmesg", kdb_dmesg, "[lines]",
2862 "Display syslog buffer", 0,
2863 KDB_ENABLE_ALWAYS_SAFE);
2864#endif
2865 if (arch_kgdb_ops.enable_nmi) {
2866 kdb_register_flags("disable_nmi", kdb_disable_nmi, "",
2867 "Disable NMI entry to KDB", 0,
2868 KDB_ENABLE_ALWAYS_SAFE);
2869 }
2870 kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2871 "Define a set of commands, down to endefcmd", 0,
2872 KDB_ENABLE_ALWAYS_SAFE);
2873 kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
2874 "Send a signal to a process", 0,
2875 KDB_ENABLE_SIGNAL);
2876 kdb_register_flags("summary", kdb_summary, "",
2877 "Summarize the system", 4,
2878 KDB_ENABLE_ALWAYS_SAFE);
2879 kdb_register_flags("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]",
2880 "Display per_cpu variables", 3,
2881 KDB_ENABLE_MEM_READ);
2882 kdb_register_flags("grephelp", kdb_grep_help, "",
2883 "Display help on | grep", 0,
2884 KDB_ENABLE_ALWAYS_SAFE);
2885}
2886
2887/* Execute any commands defined in kdb_cmds. */
2888static void __init kdb_cmd_init(void)
2889{
2890 int i, diag;
2891 for (i = 0; kdb_cmds[i]; ++i) {
2892 diag = kdb_parse(kdb_cmds[i]);
2893 if (diag)
2894 kdb_printf("kdb command %s failed, kdb diag %d\n",
2895 kdb_cmds[i], diag);
2896 }
2897 if (defcmd_in_progress) {
2898 kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2899 kdb_parse("endefcmd");
2900 }
2901}
2902
2903/* Initialize kdb_printf, breakpoint tables and kdb state */
2904void __init kdb_init(int lvl)
2905{
2906 static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2907 int i;
2908
2909 if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2910 return;
2911 for (i = kdb_init_lvl; i < lvl; i++) {
2912 switch (i) {
2913 case KDB_NOT_INITIALIZED:
2914 kdb_inittab(); /* Initialize Command Table */
2915 kdb_initbptab(); /* Initialize Breakpoints */
2916 break;
2917 case KDB_INIT_EARLY:
2918 kdb_cmd_init(); /* Build kdb_cmds tables */
2919 break;
2920 }
2921 }
2922 kdb_init_lvl = lvl;
2923}
1/*
2 * Kernel Debugger Architecture Independent Main Code
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 1999-2004 Silicon Graphics, Inc. All Rights Reserved.
9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
11 * Copyright (c) 2009 Wind River Systems, Inc. All Rights Reserved.
12 */
13
14#include <linux/ctype.h>
15#include <linux/types.h>
16#include <linux/string.h>
17#include <linux/kernel.h>
18#include <linux/kmsg_dump.h>
19#include <linux/reboot.h>
20#include <linux/sched.h>
21#include <linux/sched/loadavg.h>
22#include <linux/sched/stat.h>
23#include <linux/sched/debug.h>
24#include <linux/sysrq.h>
25#include <linux/smp.h>
26#include <linux/utsname.h>
27#include <linux/vmalloc.h>
28#include <linux/atomic.h>
29#include <linux/moduleparam.h>
30#include <linux/mm.h>
31#include <linux/init.h>
32#include <linux/kallsyms.h>
33#include <linux/kgdb.h>
34#include <linux/kdb.h>
35#include <linux/notifier.h>
36#include <linux/interrupt.h>
37#include <linux/delay.h>
38#include <linux/nmi.h>
39#include <linux/time.h>
40#include <linux/ptrace.h>
41#include <linux/sysctl.h>
42#include <linux/cpu.h>
43#include <linux/kdebug.h>
44#include <linux/proc_fs.h>
45#include <linux/uaccess.h>
46#include <linux/slab.h>
47#include <linux/security.h>
48#include "kdb_private.h"
49
50#undef MODULE_PARAM_PREFIX
51#define MODULE_PARAM_PREFIX "kdb."
52
53static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
54module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
55
56char kdb_grep_string[KDB_GREP_STRLEN];
57int kdb_grepping_flag;
58EXPORT_SYMBOL(kdb_grepping_flag);
59int kdb_grep_leading;
60int kdb_grep_trailing;
61
62/*
63 * Kernel debugger state flags
64 */
65unsigned int kdb_flags;
66
67/*
68 * kdb_lock protects updates to kdb_initial_cpu. Used to
69 * single thread processors through the kernel debugger.
70 */
71int kdb_initial_cpu = -1; /* cpu number that owns kdb */
72int kdb_nextline = 1;
73int kdb_state; /* General KDB state */
74
75struct task_struct *kdb_current_task;
76struct pt_regs *kdb_current_regs;
77
78const char *kdb_diemsg;
79static int kdb_go_count;
80#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
81static unsigned int kdb_continue_catastrophic =
82 CONFIG_KDB_CONTINUE_CATASTROPHIC;
83#else
84static unsigned int kdb_continue_catastrophic;
85#endif
86
87/* kdb_cmds_head describes the available commands. */
88static LIST_HEAD(kdb_cmds_head);
89
90typedef struct _kdbmsg {
91 int km_diag; /* kdb diagnostic */
92 char *km_msg; /* Corresponding message text */
93} kdbmsg_t;
94
95#define KDBMSG(msgnum, text) \
96 { KDB_##msgnum, text }
97
98static kdbmsg_t kdbmsgs[] = {
99 KDBMSG(NOTFOUND, "Command Not Found"),
100 KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
101 KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
102 "8 is only allowed on 64 bit systems"),
103 KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
104 KDBMSG(NOTENV, "Cannot find environment variable"),
105 KDBMSG(NOENVVALUE, "Environment variable should have value"),
106 KDBMSG(NOTIMP, "Command not implemented"),
107 KDBMSG(ENVFULL, "Environment full"),
108 KDBMSG(ENVBUFFULL, "Environment buffer full"),
109 KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
110#ifdef CONFIG_CPU_XSCALE
111 KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
112#else
113 KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
114#endif
115 KDBMSG(DUPBPT, "Duplicate breakpoint address"),
116 KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
117 KDBMSG(BADMODE, "Invalid IDMODE"),
118 KDBMSG(BADINT, "Illegal numeric value"),
119 KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
120 KDBMSG(BADREG, "Invalid register name"),
121 KDBMSG(BADCPUNUM, "Invalid cpu number"),
122 KDBMSG(BADLENGTH, "Invalid length field"),
123 KDBMSG(NOBP, "No Breakpoint exists"),
124 KDBMSG(BADADDR, "Invalid address"),
125 KDBMSG(NOPERM, "Permission denied"),
126};
127#undef KDBMSG
128
129static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
130
131
132/*
133 * Initial environment. This is all kept static and local to
134 * this file. We don't want to rely on the memory allocation
135 * mechanisms in the kernel, so we use a very limited allocate-only
136 * heap for new and altered environment variables. The entire
137 * environment is limited to a fixed number of entries (add more
138 * to __env[] if required) and a fixed amount of heap (add more to
139 * KDB_ENVBUFSIZE if required).
140 */
141
142static char *__env[31] = {
143#if defined(CONFIG_SMP)
144 "PROMPT=[%d]kdb> ",
145#else
146 "PROMPT=kdb> ",
147#endif
148 "MOREPROMPT=more> ",
149 "RADIX=16",
150 "MDCOUNT=8", /* lines of md output */
151 KDB_PLATFORM_ENV,
152 "DTABCOUNT=30",
153 "NOSECT=1",
154};
155
156static const int __nenv = ARRAY_SIZE(__env);
157
158/*
159 * Update the permissions flags (kdb_cmd_enabled) to match the
160 * current lockdown state.
161 *
162 * Within this function the calls to security_locked_down() are "lazy". We
163 * avoid calling them if the current value of kdb_cmd_enabled already excludes
164 * flags that might be subject to lockdown. Additionally we deliberately check
165 * the lockdown flags independently (even though read lockdown implies write
166 * lockdown) since that results in both simpler code and clearer messages to
167 * the user on first-time debugger entry.
168 *
169 * The permission masks during a read+write lockdown permits the following
170 * flags: INSPECT, SIGNAL, REBOOT (and ALWAYS_SAFE).
171 *
172 * The INSPECT commands are not blocked during lockdown because they are
173 * not arbitrary memory reads. INSPECT covers the backtrace family (sometimes
174 * forcing them to have no arguments) and lsmod. These commands do expose
175 * some kernel state but do not allow the developer seated at the console to
176 * choose what state is reported. SIGNAL and REBOOT should not be controversial,
177 * given these are allowed for root during lockdown already.
178 */
179static void kdb_check_for_lockdown(void)
180{
181 const int write_flags = KDB_ENABLE_MEM_WRITE |
182 KDB_ENABLE_REG_WRITE |
183 KDB_ENABLE_FLOW_CTRL;
184 const int read_flags = KDB_ENABLE_MEM_READ |
185 KDB_ENABLE_REG_READ;
186
187 bool need_to_lockdown_write = false;
188 bool need_to_lockdown_read = false;
189
190 if (kdb_cmd_enabled & (KDB_ENABLE_ALL | write_flags))
191 need_to_lockdown_write =
192 security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL);
193
194 if (kdb_cmd_enabled & (KDB_ENABLE_ALL | read_flags))
195 need_to_lockdown_read =
196 security_locked_down(LOCKDOWN_DBG_READ_KERNEL);
197
198 /* De-compose KDB_ENABLE_ALL if required */
199 if (need_to_lockdown_write || need_to_lockdown_read)
200 if (kdb_cmd_enabled & KDB_ENABLE_ALL)
201 kdb_cmd_enabled = KDB_ENABLE_MASK & ~KDB_ENABLE_ALL;
202
203 if (need_to_lockdown_write)
204 kdb_cmd_enabled &= ~write_flags;
205
206 if (need_to_lockdown_read)
207 kdb_cmd_enabled &= ~read_flags;
208}
209
210/*
211 * Check whether the flags of the current command, the permissions of the kdb
212 * console and the lockdown state allow a command to be run.
213 */
214static bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
215 bool no_args)
216{
217 /* permissions comes from userspace so needs massaging slightly */
218 permissions &= KDB_ENABLE_MASK;
219 permissions |= KDB_ENABLE_ALWAYS_SAFE;
220
221 /* some commands change group when launched with no arguments */
222 if (no_args)
223 permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
224
225 flags |= KDB_ENABLE_ALL;
226
227 return permissions & flags;
228}
229
230/*
231 * kdbgetenv - This function will return the character string value of
232 * an environment variable.
233 * Parameters:
234 * match A character string representing an environment variable.
235 * Returns:
236 * NULL No environment variable matches 'match'
237 * char* Pointer to string value of environment variable.
238 */
239char *kdbgetenv(const char *match)
240{
241 char **ep = __env;
242 int matchlen = strlen(match);
243 int i;
244
245 for (i = 0; i < __nenv; i++) {
246 char *e = *ep++;
247
248 if (!e)
249 continue;
250
251 if ((strncmp(match, e, matchlen) == 0)
252 && ((e[matchlen] == '\0')
253 || (e[matchlen] == '='))) {
254 char *cp = strchr(e, '=');
255 return cp ? ++cp : "";
256 }
257 }
258 return NULL;
259}
260
261/*
262 * kdballocenv - This function is used to allocate bytes for
263 * environment entries.
264 * Parameters:
265 * bytes The number of bytes to allocate in the static buffer.
266 * Returns:
267 * A pointer to the allocated space in the buffer on success.
268 * NULL if bytes > size available in the envbuffer.
269 * Remarks:
270 * We use a static environment buffer (envbuffer) to hold the values
271 * of dynamically generated environment variables (see kdb_set). Buffer
272 * space once allocated is never free'd, so over time, the amount of space
273 * (currently 512 bytes) will be exhausted if env variables are changed
274 * frequently.
275 */
276static char *kdballocenv(size_t bytes)
277{
278#define KDB_ENVBUFSIZE 512
279 static char envbuffer[KDB_ENVBUFSIZE];
280 static int envbufsize;
281 char *ep = NULL;
282
283 if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
284 ep = &envbuffer[envbufsize];
285 envbufsize += bytes;
286 }
287 return ep;
288}
289
290/*
291 * kdbgetulenv - This function will return the value of an unsigned
292 * long-valued environment variable.
293 * Parameters:
294 * match A character string representing a numeric value
295 * Outputs:
296 * *value the unsigned long representation of the env variable 'match'
297 * Returns:
298 * Zero on success, a kdb diagnostic on failure.
299 */
300static int kdbgetulenv(const char *match, unsigned long *value)
301{
302 char *ep;
303
304 ep = kdbgetenv(match);
305 if (!ep)
306 return KDB_NOTENV;
307 if (strlen(ep) == 0)
308 return KDB_NOENVVALUE;
309 if (kstrtoul(ep, 0, value))
310 return KDB_BADINT;
311
312 return 0;
313}
314
315/*
316 * kdbgetintenv - This function will return the value of an
317 * integer-valued environment variable.
318 * Parameters:
319 * match A character string representing an integer-valued env variable
320 * Outputs:
321 * *value the integer representation of the environment variable 'match'
322 * Returns:
323 * Zero on success, a kdb diagnostic on failure.
324 */
325int kdbgetintenv(const char *match, int *value)
326{
327 unsigned long val;
328 int diag;
329
330 diag = kdbgetulenv(match, &val);
331 if (!diag)
332 *value = (int) val;
333 return diag;
334}
335
336/*
337 * kdb_setenv() - Alter an existing environment variable or create a new one.
338 * @var: Name of the variable
339 * @val: Value of the variable
340 *
341 * Return: Zero on success, a kdb diagnostic on failure.
342 */
343static int kdb_setenv(const char *var, const char *val)
344{
345 int i;
346 char *ep;
347 size_t varlen, vallen;
348
349 varlen = strlen(var);
350 vallen = strlen(val);
351 ep = kdballocenv(varlen + vallen + 2);
352 if (ep == (char *)0)
353 return KDB_ENVBUFFULL;
354
355 sprintf(ep, "%s=%s", var, val);
356
357 for (i = 0; i < __nenv; i++) {
358 if (__env[i]
359 && ((strncmp(__env[i], var, varlen) == 0)
360 && ((__env[i][varlen] == '\0')
361 || (__env[i][varlen] == '=')))) {
362 __env[i] = ep;
363 return 0;
364 }
365 }
366
367 /*
368 * Wasn't existing variable. Fit into slot.
369 */
370 for (i = 0; i < __nenv-1; i++) {
371 if (__env[i] == (char *)0) {
372 __env[i] = ep;
373 return 0;
374 }
375 }
376
377 return KDB_ENVFULL;
378}
379
380/*
381 * kdb_printenv() - Display the current environment variables.
382 */
383static void kdb_printenv(void)
384{
385 int i;
386
387 for (i = 0; i < __nenv; i++) {
388 if (__env[i])
389 kdb_printf("%s\n", __env[i]);
390 }
391}
392
393/*
394 * kdbgetularg - This function will convert a numeric string into an
395 * unsigned long value.
396 * Parameters:
397 * arg A character string representing a numeric value
398 * Outputs:
399 * *value the unsigned long representation of arg.
400 * Returns:
401 * Zero on success, a kdb diagnostic on failure.
402 */
403int kdbgetularg(const char *arg, unsigned long *value)
404{
405 if (kstrtoul(arg, 0, value))
406 return KDB_BADINT;
407 return 0;
408}
409
410int kdbgetu64arg(const char *arg, u64 *value)
411{
412 if (kstrtou64(arg, 0, value))
413 return KDB_BADINT;
414 return 0;
415}
416
417/*
418 * kdb_set - This function implements the 'set' command. Alter an
419 * existing environment variable or create a new one.
420 */
421int kdb_set(int argc, const char **argv)
422{
423 /*
424 * we can be invoked two ways:
425 * set var=value argv[1]="var", argv[2]="value"
426 * set var = value argv[1]="var", argv[2]="=", argv[3]="value"
427 * - if the latter, shift 'em down.
428 */
429 if (argc == 3) {
430 argv[2] = argv[3];
431 argc--;
432 }
433
434 if (argc != 2)
435 return KDB_ARGCOUNT;
436
437 /*
438 * Censor sensitive variables
439 */
440 if (strcmp(argv[1], "PROMPT") == 0 &&
441 !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
442 return KDB_NOPERM;
443
444 /*
445 * Check for internal variables
446 */
447 if (strcmp(argv[1], "KDBDEBUG") == 0) {
448 unsigned int debugflags;
449 int ret;
450
451 ret = kstrtouint(argv[2], 0, &debugflags);
452 if (ret || debugflags & ~KDB_DEBUG_FLAG_MASK) {
453 kdb_printf("kdb: illegal debug flags '%s'\n",
454 argv[2]);
455 return 0;
456 }
457 kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
458 | (debugflags << KDB_DEBUG_FLAG_SHIFT);
459
460 return 0;
461 }
462
463 /*
464 * Tokenizer squashed the '=' sign. argv[1] is variable
465 * name, argv[2] = value.
466 */
467 return kdb_setenv(argv[1], argv[2]);
468}
469
470static int kdb_check_regs(void)
471{
472 if (!kdb_current_regs) {
473 kdb_printf("No current kdb registers."
474 " You may need to select another task\n");
475 return KDB_BADREG;
476 }
477 return 0;
478}
479
480/*
481 * kdbgetaddrarg - This function is responsible for parsing an
482 * address-expression and returning the value of the expression,
483 * symbol name, and offset to the caller.
484 *
485 * The argument may consist of a numeric value (decimal or
486 * hexadecimal), a symbol name, a register name (preceded by the
487 * percent sign), an environment variable with a numeric value
488 * (preceded by a dollar sign) or a simple arithmetic expression
489 * consisting of a symbol name, +/-, and a numeric constant value
490 * (offset).
491 * Parameters:
492 * argc - count of arguments in argv
493 * argv - argument vector
494 * *nextarg - index to next unparsed argument in argv[]
495 * regs - Register state at time of KDB entry
496 * Outputs:
497 * *value - receives the value of the address-expression
498 * *offset - receives the offset specified, if any
499 * *name - receives the symbol name, if any
500 * *nextarg - index to next unparsed argument in argv[]
501 * Returns:
502 * zero is returned on success, a kdb diagnostic code is
503 * returned on error.
504 */
505int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
506 unsigned long *value, long *offset,
507 char **name)
508{
509 unsigned long addr;
510 unsigned long off = 0;
511 int positive;
512 int diag;
513 int found = 0;
514 char *symname;
515 char symbol = '\0';
516 char *cp;
517 kdb_symtab_t symtab;
518
519 /*
520 * If the enable flags prohibit both arbitrary memory access
521 * and flow control then there are no reasonable grounds to
522 * provide symbol lookup.
523 */
524 if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
525 kdb_cmd_enabled, false))
526 return KDB_NOPERM;
527
528 /*
529 * Process arguments which follow the following syntax:
530 *
531 * symbol | numeric-address [+/- numeric-offset]
532 * %register
533 * $environment-variable
534 */
535
536 if (*nextarg > argc)
537 return KDB_ARGCOUNT;
538
539 symname = (char *)argv[*nextarg];
540
541 /*
542 * If there is no whitespace between the symbol
543 * or address and the '+' or '-' symbols, we
544 * remember the character and replace it with a
545 * null so the symbol/value can be properly parsed
546 */
547 cp = strpbrk(symname, "+-");
548 if (cp != NULL) {
549 symbol = *cp;
550 *cp++ = '\0';
551 }
552
553 if (symname[0] == '$') {
554 diag = kdbgetulenv(&symname[1], &addr);
555 if (diag)
556 return diag;
557 } else if (symname[0] == '%') {
558 diag = kdb_check_regs();
559 if (diag)
560 return diag;
561 /* Implement register values with % at a later time as it is
562 * arch optional.
563 */
564 return KDB_NOTIMP;
565 } else {
566 found = kdbgetsymval(symname, &symtab);
567 if (found) {
568 addr = symtab.sym_start;
569 } else {
570 diag = kdbgetularg(argv[*nextarg], &addr);
571 if (diag)
572 return diag;
573 }
574 }
575
576 if (!found)
577 found = kdbnearsym(addr, &symtab);
578
579 (*nextarg)++;
580
581 if (name)
582 *name = symname;
583 if (value)
584 *value = addr;
585 if (offset && name && *name)
586 *offset = addr - symtab.sym_start;
587
588 if ((*nextarg > argc)
589 && (symbol == '\0'))
590 return 0;
591
592 /*
593 * check for +/- and offset
594 */
595
596 if (symbol == '\0') {
597 if ((argv[*nextarg][0] != '+')
598 && (argv[*nextarg][0] != '-')) {
599 /*
600 * Not our argument. Return.
601 */
602 return 0;
603 } else {
604 positive = (argv[*nextarg][0] == '+');
605 (*nextarg)++;
606 }
607 } else
608 positive = (symbol == '+');
609
610 /*
611 * Now there must be an offset!
612 */
613 if ((*nextarg > argc)
614 && (symbol == '\0')) {
615 return KDB_INVADDRFMT;
616 }
617
618 if (!symbol) {
619 cp = (char *)argv[*nextarg];
620 (*nextarg)++;
621 }
622
623 diag = kdbgetularg(cp, &off);
624 if (diag)
625 return diag;
626
627 if (!positive)
628 off = -off;
629
630 if (offset)
631 *offset += off;
632
633 if (value)
634 *value += off;
635
636 return 0;
637}
638
639static void kdb_cmderror(int diag)
640{
641 int i;
642
643 if (diag >= 0) {
644 kdb_printf("no error detected (diagnostic is %d)\n", diag);
645 return;
646 }
647
648 for (i = 0; i < __nkdb_err; i++) {
649 if (kdbmsgs[i].km_diag == diag) {
650 kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
651 return;
652 }
653 }
654
655 kdb_printf("Unknown diag %d\n", -diag);
656}
657
658/*
659 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
660 * command which defines one command as a set of other commands,
661 * terminated by endefcmd. kdb_defcmd processes the initial
662 * 'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
663 * the following commands until 'endefcmd'.
664 * Inputs:
665 * argc argument count
666 * argv argument vector
667 * Returns:
668 * zero for success, a kdb diagnostic if error
669 */
670struct kdb_macro {
671 kdbtab_t cmd; /* Macro command */
672 struct list_head statements; /* Associated statement list */
673};
674
675struct kdb_macro_statement {
676 char *statement; /* Statement text */
677 struct list_head list_node; /* Statement list node */
678};
679
680static struct kdb_macro *kdb_macro;
681static bool defcmd_in_progress;
682
683/* Forward references */
684static int kdb_exec_defcmd(int argc, const char **argv);
685
686static int kdb_defcmd2(const char *cmdstr, const char *argv0)
687{
688 struct kdb_macro_statement *kms;
689
690 if (!kdb_macro)
691 return KDB_NOTIMP;
692
693 if (strcmp(argv0, "endefcmd") == 0) {
694 defcmd_in_progress = false;
695 if (!list_empty(&kdb_macro->statements))
696 kdb_register(&kdb_macro->cmd);
697 return 0;
698 }
699
700 kms = kmalloc(sizeof(*kms), GFP_KDB);
701 if (!kms) {
702 kdb_printf("Could not allocate new kdb macro command: %s\n",
703 cmdstr);
704 return KDB_NOTIMP;
705 }
706
707 kms->statement = kdb_strdup(cmdstr, GFP_KDB);
708 list_add_tail(&kms->list_node, &kdb_macro->statements);
709
710 return 0;
711}
712
713static int kdb_defcmd(int argc, const char **argv)
714{
715 kdbtab_t *mp;
716
717 if (defcmd_in_progress) {
718 kdb_printf("kdb: nested defcmd detected, assuming missing "
719 "endefcmd\n");
720 kdb_defcmd2("endefcmd", "endefcmd");
721 }
722 if (argc == 0) {
723 kdbtab_t *kp;
724 struct kdb_macro *kmp;
725 struct kdb_macro_statement *kms;
726
727 list_for_each_entry(kp, &kdb_cmds_head, list_node) {
728 if (kp->func == kdb_exec_defcmd) {
729 kdb_printf("defcmd %s \"%s\" \"%s\"\n",
730 kp->name, kp->usage, kp->help);
731 kmp = container_of(kp, struct kdb_macro, cmd);
732 list_for_each_entry(kms, &kmp->statements,
733 list_node)
734 kdb_printf("%s", kms->statement);
735 kdb_printf("endefcmd\n");
736 }
737 }
738 return 0;
739 }
740 if (argc != 3)
741 return KDB_ARGCOUNT;
742 if (in_dbg_master()) {
743 kdb_printf("Command only available during kdb_init()\n");
744 return KDB_NOTIMP;
745 }
746 kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);
747 if (!kdb_macro)
748 goto fail_defcmd;
749
750 mp = &kdb_macro->cmd;
751 mp->func = kdb_exec_defcmd;
752 mp->minlen = 0;
753 mp->flags = KDB_ENABLE_ALWAYS_SAFE;
754 mp->name = kdb_strdup(argv[1], GFP_KDB);
755 if (!mp->name)
756 goto fail_name;
757 mp->usage = kdb_strdup(argv[2], GFP_KDB);
758 if (!mp->usage)
759 goto fail_usage;
760 mp->help = kdb_strdup(argv[3], GFP_KDB);
761 if (!mp->help)
762 goto fail_help;
763 if (mp->usage[0] == '"') {
764 strcpy(mp->usage, argv[2]+1);
765 mp->usage[strlen(mp->usage)-1] = '\0';
766 }
767 if (mp->help[0] == '"') {
768 strcpy(mp->help, argv[3]+1);
769 mp->help[strlen(mp->help)-1] = '\0';
770 }
771
772 INIT_LIST_HEAD(&kdb_macro->statements);
773 defcmd_in_progress = true;
774 return 0;
775fail_help:
776 kfree(mp->usage);
777fail_usage:
778 kfree(mp->name);
779fail_name:
780 kfree(kdb_macro);
781fail_defcmd:
782 kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
783 return KDB_NOTIMP;
784}
785
786/*
787 * kdb_exec_defcmd - Execute the set of commands associated with this
788 * defcmd name.
789 * Inputs:
790 * argc argument count
791 * argv argument vector
792 * Returns:
793 * zero for success, a kdb diagnostic if error
794 */
795static int kdb_exec_defcmd(int argc, const char **argv)
796{
797 int ret;
798 kdbtab_t *kp;
799 struct kdb_macro *kmp;
800 struct kdb_macro_statement *kms;
801
802 if (argc != 0)
803 return KDB_ARGCOUNT;
804
805 list_for_each_entry(kp, &kdb_cmds_head, list_node) {
806 if (strcmp(kp->name, argv[0]) == 0)
807 break;
808 }
809 if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
810 kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
811 argv[0]);
812 return KDB_NOTIMP;
813 }
814 kmp = container_of(kp, struct kdb_macro, cmd);
815 list_for_each_entry(kms, &kmp->statements, list_node) {
816 /*
817 * Recursive use of kdb_parse, do not use argv after this point.
818 */
819 argv = NULL;
820 kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement);
821 ret = kdb_parse(kms->statement);
822 if (ret)
823 return ret;
824 }
825 return 0;
826}
827
828/* Command history */
829#define KDB_CMD_HISTORY_COUNT 32
830#define CMD_BUFLEN 200 /* kdb_printf: max printline
831 * size == 256 */
832static unsigned int cmd_head, cmd_tail;
833static unsigned int cmdptr;
834static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
835static char cmd_cur[CMD_BUFLEN];
836
837/*
838 * The "str" argument may point to something like | grep xyz
839 */
840static void parse_grep(const char *str)
841{
842 int len;
843 char *cp = (char *)str, *cp2;
844
845 /* sanity check: we should have been called with the \ first */
846 if (*cp != '|')
847 return;
848 cp++;
849 while (isspace(*cp))
850 cp++;
851 if (!str_has_prefix(cp, "grep ")) {
852 kdb_printf("invalid 'pipe', see grephelp\n");
853 return;
854 }
855 cp += 5;
856 while (isspace(*cp))
857 cp++;
858 cp2 = strchr(cp, '\n');
859 if (cp2)
860 *cp2 = '\0'; /* remove the trailing newline */
861 len = strlen(cp);
862 if (len == 0) {
863 kdb_printf("invalid 'pipe', see grephelp\n");
864 return;
865 }
866 /* now cp points to a nonzero length search string */
867 if (*cp == '"') {
868 /* allow it be "x y z" by removing the "'s - there must
869 be two of them */
870 cp++;
871 cp2 = strchr(cp, '"');
872 if (!cp2) {
873 kdb_printf("invalid quoted string, see grephelp\n");
874 return;
875 }
876 *cp2 = '\0'; /* end the string where the 2nd " was */
877 }
878 kdb_grep_leading = 0;
879 if (*cp == '^') {
880 kdb_grep_leading = 1;
881 cp++;
882 }
883 len = strlen(cp);
884 kdb_grep_trailing = 0;
885 if (*(cp+len-1) == '$') {
886 kdb_grep_trailing = 1;
887 *(cp+len-1) = '\0';
888 }
889 len = strlen(cp);
890 if (!len)
891 return;
892 if (len >= KDB_GREP_STRLEN) {
893 kdb_printf("search string too long\n");
894 return;
895 }
896 strcpy(kdb_grep_string, cp);
897 kdb_grepping_flag++;
898 return;
899}
900
901/*
902 * kdb_parse - Parse the command line, search the command table for a
903 * matching command and invoke the command function. This
904 * function may be called recursively, if it is, the second call
905 * will overwrite argv and cbuf. It is the caller's
906 * responsibility to save their argv if they recursively call
907 * kdb_parse().
908 * Parameters:
909 * cmdstr The input command line to be parsed.
910 * regs The registers at the time kdb was entered.
911 * Returns:
912 * Zero for success, a kdb diagnostic if failure.
913 * Remarks:
914 * Limited to 20 tokens.
915 *
916 * Real rudimentary tokenization. Basically only whitespace
917 * is considered a token delimiter (but special consideration
918 * is taken of the '=' sign as used by the 'set' command).
919 *
920 * The algorithm used to tokenize the input string relies on
921 * there being at least one whitespace (or otherwise useless)
922 * character between tokens as the character immediately following
923 * the token is altered in-place to a null-byte to terminate the
924 * token string.
925 */
926
927#define MAXARGC 20
928
929int kdb_parse(const char *cmdstr)
930{
931 static char *argv[MAXARGC];
932 static int argc;
933 static char cbuf[CMD_BUFLEN+2];
934 char *cp;
935 char *cpp, quoted;
936 kdbtab_t *tp;
937 int escaped, ignore_errors = 0, check_grep = 0;
938
939 /*
940 * First tokenize the command string.
941 */
942 cp = (char *)cmdstr;
943
944 if (KDB_FLAG(CMD_INTERRUPT)) {
945 /* Previous command was interrupted, newline must not
946 * repeat the command */
947 KDB_FLAG_CLEAR(CMD_INTERRUPT);
948 KDB_STATE_SET(PAGER);
949 argc = 0; /* no repeat */
950 }
951
952 if (*cp != '\n' && *cp != '\0') {
953 argc = 0;
954 cpp = cbuf;
955 while (*cp) {
956 /* skip whitespace */
957 while (isspace(*cp))
958 cp++;
959 if ((*cp == '\0') || (*cp == '\n') ||
960 (*cp == '#' && !defcmd_in_progress))
961 break;
962 /* special case: check for | grep pattern */
963 if (*cp == '|') {
964 check_grep++;
965 break;
966 }
967 if (cpp >= cbuf + CMD_BUFLEN) {
968 kdb_printf("kdb_parse: command buffer "
969 "overflow, command ignored\n%s\n",
970 cmdstr);
971 return KDB_NOTFOUND;
972 }
973 if (argc >= MAXARGC - 1) {
974 kdb_printf("kdb_parse: too many arguments, "
975 "command ignored\n%s\n", cmdstr);
976 return KDB_NOTFOUND;
977 }
978 argv[argc++] = cpp;
979 escaped = 0;
980 quoted = '\0';
981 /* Copy to next unquoted and unescaped
982 * whitespace or '=' */
983 while (*cp && *cp != '\n' &&
984 (escaped || quoted || !isspace(*cp))) {
985 if (cpp >= cbuf + CMD_BUFLEN)
986 break;
987 if (escaped) {
988 escaped = 0;
989 *cpp++ = *cp++;
990 continue;
991 }
992 if (*cp == '\\') {
993 escaped = 1;
994 ++cp;
995 continue;
996 }
997 if (*cp == quoted)
998 quoted = '\0';
999 else if (*cp == '\'' || *cp == '"')
1000 quoted = *cp;
1001 *cpp = *cp++;
1002 if (*cpp == '=' && !quoted)
1003 break;
1004 ++cpp;
1005 }
1006 *cpp++ = '\0'; /* Squash a ws or '=' character */
1007 }
1008 }
1009 if (!argc)
1010 return 0;
1011 if (check_grep)
1012 parse_grep(cp);
1013 if (defcmd_in_progress) {
1014 int result = kdb_defcmd2(cmdstr, argv[0]);
1015 if (!defcmd_in_progress) {
1016 argc = 0; /* avoid repeat on endefcmd */
1017 *(argv[0]) = '\0';
1018 }
1019 return result;
1020 }
1021 if (argv[0][0] == '-' && argv[0][1] &&
1022 (argv[0][1] < '0' || argv[0][1] > '9')) {
1023 ignore_errors = 1;
1024 ++argv[0];
1025 }
1026
1027 list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1028 /*
1029 * If this command is allowed to be abbreviated,
1030 * check to see if this is it.
1031 */
1032 if (tp->minlen && (strlen(argv[0]) <= tp->minlen) &&
1033 (strncmp(argv[0], tp->name, tp->minlen) == 0))
1034 break;
1035
1036 if (strcmp(argv[0], tp->name) == 0)
1037 break;
1038 }
1039
1040 /*
1041 * If we don't find a command by this name, see if the first
1042 * few characters of this match any of the known commands.
1043 * e.g., md1c20 should match md.
1044 */
1045 if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1046 list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1047 if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0)
1048 break;
1049 }
1050 }
1051
1052 if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1053 int result;
1054
1055 if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1))
1056 return KDB_NOPERM;
1057
1058 KDB_STATE_SET(CMD);
1059 result = (*tp->func)(argc-1, (const char **)argv);
1060 if (result && ignore_errors && result > KDB_CMD_GO)
1061 result = 0;
1062 KDB_STATE_CLEAR(CMD);
1063
1064 if (tp->flags & KDB_REPEAT_WITH_ARGS)
1065 return result;
1066
1067 argc = tp->flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1068 if (argv[argc])
1069 *(argv[argc]) = '\0';
1070 return result;
1071 }
1072
1073 /*
1074 * If the input with which we were presented does not
1075 * map to an existing command, attempt to parse it as an
1076 * address argument and display the result. Useful for
1077 * obtaining the address of a variable, or the nearest symbol
1078 * to an address contained in a register.
1079 */
1080 {
1081 unsigned long value;
1082 char *name = NULL;
1083 long offset;
1084 int nextarg = 0;
1085
1086 if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1087 &value, &offset, &name)) {
1088 return KDB_NOTFOUND;
1089 }
1090
1091 kdb_printf("%s = ", argv[0]);
1092 kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1093 kdb_printf("\n");
1094 return 0;
1095 }
1096}
1097
1098
1099static int handle_ctrl_cmd(char *cmd)
1100{
1101#define CTRL_P 16
1102#define CTRL_N 14
1103
1104 /* initial situation */
1105 if (cmd_head == cmd_tail)
1106 return 0;
1107 switch (*cmd) {
1108 case CTRL_P:
1109 if (cmdptr != cmd_tail)
1110 cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) %
1111 KDB_CMD_HISTORY_COUNT;
1112 strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1113 return 1;
1114 case CTRL_N:
1115 if (cmdptr != cmd_head)
1116 cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1117 strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1118 return 1;
1119 }
1120 return 0;
1121}
1122
1123/*
1124 * kdb_reboot - This function implements the 'reboot' command. Reboot
1125 * the system immediately, or loop for ever on failure.
1126 */
1127static int kdb_reboot(int argc, const char **argv)
1128{
1129 emergency_restart();
1130 kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1131 while (1)
1132 cpu_relax();
1133 /* NOTREACHED */
1134 return 0;
1135}
1136
1137static void kdb_dumpregs(struct pt_regs *regs)
1138{
1139 int old_lvl = console_loglevel;
1140 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1141 kdb_trap_printk++;
1142 show_regs(regs);
1143 kdb_trap_printk--;
1144 kdb_printf("\n");
1145 console_loglevel = old_lvl;
1146}
1147
1148static void kdb_set_current_task(struct task_struct *p)
1149{
1150 kdb_current_task = p;
1151
1152 if (kdb_task_has_cpu(p)) {
1153 kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1154 return;
1155 }
1156 kdb_current_regs = NULL;
1157}
1158
1159static void drop_newline(char *buf)
1160{
1161 size_t len = strlen(buf);
1162
1163 if (len == 0)
1164 return;
1165 if (*(buf + len - 1) == '\n')
1166 *(buf + len - 1) = '\0';
1167}
1168
1169/*
1170 * kdb_local - The main code for kdb. This routine is invoked on a
1171 * specific processor, it is not global. The main kdb() routine
1172 * ensures that only one processor at a time is in this routine.
1173 * This code is called with the real reason code on the first
1174 * entry to a kdb session, thereafter it is called with reason
1175 * SWITCH, even if the user goes back to the original cpu.
1176 * Inputs:
1177 * reason The reason KDB was invoked
1178 * error The hardware-defined error code
1179 * regs The exception frame at time of fault/breakpoint.
1180 * db_result Result code from the break or debug point.
1181 * Returns:
1182 * 0 KDB was invoked for an event which it wasn't responsible
1183 * 1 KDB handled the event for which it was invoked.
1184 * KDB_CMD_GO User typed 'go'.
1185 * KDB_CMD_CPU User switched to another cpu.
1186 * KDB_CMD_SS Single step.
1187 */
1188static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1189 kdb_dbtrap_t db_result)
1190{
1191 char *cmdbuf;
1192 int diag;
1193 struct task_struct *kdb_current =
1194 curr_task(raw_smp_processor_id());
1195
1196 KDB_DEBUG_STATE("kdb_local 1", reason);
1197
1198 kdb_check_for_lockdown();
1199
1200 kdb_go_count = 0;
1201 if (reason == KDB_REASON_DEBUG) {
1202 /* special case below */
1203 } else {
1204 kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1205 kdb_current, kdb_current ? kdb_current->pid : 0);
1206#if defined(CONFIG_SMP)
1207 kdb_printf("on processor %d ", raw_smp_processor_id());
1208#endif
1209 }
1210
1211 switch (reason) {
1212 case KDB_REASON_DEBUG:
1213 {
1214 /*
1215 * If re-entering kdb after a single step
1216 * command, don't print the message.
1217 */
1218 switch (db_result) {
1219 case KDB_DB_BPT:
1220 kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1221 kdb_current, kdb_current->pid);
1222#if defined(CONFIG_SMP)
1223 kdb_printf("on processor %d ", raw_smp_processor_id());
1224#endif
1225 kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1226 instruction_pointer(regs));
1227 break;
1228 case KDB_DB_SS:
1229 break;
1230 case KDB_DB_SSBPT:
1231 KDB_DEBUG_STATE("kdb_local 4", reason);
1232 return 1; /* kdba_db_trap did the work */
1233 default:
1234 kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1235 db_result);
1236 break;
1237 }
1238
1239 }
1240 break;
1241 case KDB_REASON_ENTER:
1242 if (KDB_STATE(KEYBOARD))
1243 kdb_printf("due to Keyboard Entry\n");
1244 else
1245 kdb_printf("due to KDB_ENTER()\n");
1246 break;
1247 case KDB_REASON_KEYBOARD:
1248 KDB_STATE_SET(KEYBOARD);
1249 kdb_printf("due to Keyboard Entry\n");
1250 break;
1251 case KDB_REASON_ENTER_SLAVE:
1252 /* drop through, slaves only get released via cpu switch */
1253 case KDB_REASON_SWITCH:
1254 kdb_printf("due to cpu switch\n");
1255 break;
1256 case KDB_REASON_OOPS:
1257 kdb_printf("Oops: %s\n", kdb_diemsg);
1258 kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1259 instruction_pointer(regs));
1260 kdb_dumpregs(regs);
1261 break;
1262 case KDB_REASON_SYSTEM_NMI:
1263 kdb_printf("due to System NonMaskable Interrupt\n");
1264 break;
1265 case KDB_REASON_NMI:
1266 kdb_printf("due to NonMaskable Interrupt @ "
1267 kdb_machreg_fmt "\n",
1268 instruction_pointer(regs));
1269 break;
1270 case KDB_REASON_SSTEP:
1271 case KDB_REASON_BREAK:
1272 kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1273 reason == KDB_REASON_BREAK ?
1274 "Breakpoint" : "SS trap", instruction_pointer(regs));
1275 /*
1276 * Determine if this breakpoint is one that we
1277 * are interested in.
1278 */
1279 if (db_result != KDB_DB_BPT) {
1280 kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1281 db_result);
1282 KDB_DEBUG_STATE("kdb_local 6", reason);
1283 return 0; /* Not for us, dismiss it */
1284 }
1285 break;
1286 case KDB_REASON_RECURSE:
1287 kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1288 instruction_pointer(regs));
1289 break;
1290 default:
1291 kdb_printf("kdb: unexpected reason code: %d\n", reason);
1292 KDB_DEBUG_STATE("kdb_local 8", reason);
1293 return 0; /* Not for us, dismiss it */
1294 }
1295
1296 while (1) {
1297 /*
1298 * Initialize pager context.
1299 */
1300 kdb_nextline = 1;
1301 KDB_STATE_CLEAR(SUPPRESS);
1302 kdb_grepping_flag = 0;
1303 /* ensure the old search does not leak into '/' commands */
1304 kdb_grep_string[0] = '\0';
1305
1306 cmdbuf = cmd_cur;
1307 *cmdbuf = '\0';
1308 *(cmd_hist[cmd_head]) = '\0';
1309
1310do_full_getstr:
1311 /* PROMPT can only be set if we have MEM_READ permission. */
1312 snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1313 raw_smp_processor_id());
1314
1315 /*
1316 * Fetch command from keyboard
1317 */
1318 cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1319 if (*cmdbuf != '\n') {
1320 if (*cmdbuf < 32) {
1321 if (cmdptr == cmd_head) {
1322 strscpy(cmd_hist[cmd_head], cmd_cur,
1323 CMD_BUFLEN);
1324 *(cmd_hist[cmd_head] +
1325 strlen(cmd_hist[cmd_head])-1) = '\0';
1326 }
1327 if (!handle_ctrl_cmd(cmdbuf))
1328 *(cmd_cur+strlen(cmd_cur)-1) = '\0';
1329 cmdbuf = cmd_cur;
1330 goto do_full_getstr;
1331 } else {
1332 strscpy(cmd_hist[cmd_head], cmd_cur,
1333 CMD_BUFLEN);
1334 }
1335
1336 cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1337 if (cmd_head == cmd_tail)
1338 cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1339 }
1340
1341 cmdptr = cmd_head;
1342 diag = kdb_parse(cmdbuf);
1343 if (diag == KDB_NOTFOUND) {
1344 drop_newline(cmdbuf);
1345 kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1346 diag = 0;
1347 }
1348 if (diag == KDB_CMD_GO
1349 || diag == KDB_CMD_CPU
1350 || diag == KDB_CMD_SS
1351 || diag == KDB_CMD_KGDB)
1352 break;
1353
1354 if (diag)
1355 kdb_cmderror(diag);
1356 }
1357 KDB_DEBUG_STATE("kdb_local 9", diag);
1358 return diag;
1359}
1360
1361
1362/*
1363 * kdb_print_state - Print the state data for the current processor
1364 * for debugging.
1365 * Inputs:
1366 * text Identifies the debug point
1367 * value Any integer value to be printed, e.g. reason code.
1368 */
1369void kdb_print_state(const char *text, int value)
1370{
1371 kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1372 text, raw_smp_processor_id(), value, kdb_initial_cpu,
1373 kdb_state);
1374}
1375
1376/*
1377 * kdb_main_loop - After initial setup and assignment of the
1378 * controlling cpu, all cpus are in this loop. One cpu is in
1379 * control and will issue the kdb prompt, the others will spin
1380 * until 'go' or cpu switch.
1381 *
1382 * To get a consistent view of the kernel stacks for all
1383 * processes, this routine is invoked from the main kdb code via
1384 * an architecture specific routine. kdba_main_loop is
1385 * responsible for making the kernel stacks consistent for all
1386 * processes, there should be no difference between a blocked
1387 * process and a running process as far as kdb is concerned.
1388 * Inputs:
1389 * reason The reason KDB was invoked
1390 * error The hardware-defined error code
1391 * reason2 kdb's current reason code.
1392 * Initially error but can change
1393 * according to kdb state.
1394 * db_result Result code from break or debug point.
1395 * regs The exception frame at time of fault/breakpoint.
1396 * should always be valid.
1397 * Returns:
1398 * 0 KDB was invoked for an event which it wasn't responsible
1399 * 1 KDB handled the event for which it was invoked.
1400 */
1401int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1402 kdb_dbtrap_t db_result, struct pt_regs *regs)
1403{
1404 int result = 1;
1405 /* Stay in kdb() until 'go', 'ss[b]' or an error */
1406 while (1) {
1407 /*
1408 * All processors except the one that is in control
1409 * will spin here.
1410 */
1411 KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1412 while (KDB_STATE(HOLD_CPU)) {
1413 /* state KDB is turned off by kdb_cpu to see if the
1414 * other cpus are still live, each cpu in this loop
1415 * turns it back on.
1416 */
1417 if (!KDB_STATE(KDB))
1418 KDB_STATE_SET(KDB);
1419 }
1420
1421 KDB_STATE_CLEAR(SUPPRESS);
1422 KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1423 if (KDB_STATE(LEAVING))
1424 break; /* Another cpu said 'go' */
1425 /* Still using kdb, this processor is in control */
1426 result = kdb_local(reason2, error, regs, db_result);
1427 KDB_DEBUG_STATE("kdb_main_loop 3", result);
1428
1429 if (result == KDB_CMD_CPU)
1430 break;
1431
1432 if (result == KDB_CMD_SS) {
1433 KDB_STATE_SET(DOING_SS);
1434 break;
1435 }
1436
1437 if (result == KDB_CMD_KGDB) {
1438 if (!KDB_STATE(DOING_KGDB))
1439 kdb_printf("Entering please attach debugger "
1440 "or use $D#44+ or $3#33\n");
1441 break;
1442 }
1443 if (result && result != 1 && result != KDB_CMD_GO)
1444 kdb_printf("\nUnexpected kdb_local return code %d\n",
1445 result);
1446 KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1447 break;
1448 }
1449 if (KDB_STATE(DOING_SS))
1450 KDB_STATE_CLEAR(SSBPT);
1451
1452 /* Clean up any keyboard devices before leaving */
1453 kdb_kbd_cleanup_state();
1454
1455 return result;
1456}
1457
1458/*
1459 * kdb_mdr - This function implements the guts of the 'mdr', memory
1460 * read command.
1461 * mdr <addr arg>,<byte count>
1462 * Inputs:
1463 * addr Start address
1464 * count Number of bytes
1465 * Returns:
1466 * Always 0. Any errors are detected and printed by kdb_getarea.
1467 */
1468static int kdb_mdr(unsigned long addr, unsigned int count)
1469{
1470 unsigned char c;
1471 while (count--) {
1472 if (kdb_getarea(c, addr))
1473 return 0;
1474 kdb_printf("%02x", c);
1475 addr++;
1476 }
1477 kdb_printf("\n");
1478 return 0;
1479}
1480
1481/*
1482 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1483 * 'md8' 'mdr' and 'mds' commands.
1484 *
1485 * md|mds [<addr arg> [<line count> [<radix>]]]
1486 * mdWcN [<addr arg> [<line count> [<radix>]]]
1487 * where W = is the width (1, 2, 4 or 8) and N is the count.
1488 * for eg., md1c20 reads 20 bytes, 1 at a time.
1489 * mdr <addr arg>,<byte count>
1490 */
1491static void kdb_md_line(const char *fmtstr, unsigned long addr,
1492 int symbolic, int nosect, int bytesperword,
1493 int num, int repeat, int phys)
1494{
1495 /* print just one line of data */
1496 kdb_symtab_t symtab;
1497 char cbuf[32];
1498 char *c = cbuf;
1499 int i;
1500 int j;
1501 unsigned long word;
1502
1503 memset(cbuf, '\0', sizeof(cbuf));
1504 if (phys)
1505 kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1506 else
1507 kdb_printf(kdb_machreg_fmt0 " ", addr);
1508
1509 for (i = 0; i < num && repeat--; i++) {
1510 if (phys) {
1511 if (kdb_getphysword(&word, addr, bytesperword))
1512 break;
1513 } else if (kdb_getword(&word, addr, bytesperword))
1514 break;
1515 kdb_printf(fmtstr, word);
1516 if (symbolic)
1517 kdbnearsym(word, &symtab);
1518 else
1519 memset(&symtab, 0, sizeof(symtab));
1520 if (symtab.sym_name) {
1521 kdb_symbol_print(word, &symtab, 0);
1522 if (!nosect) {
1523 kdb_printf("\n");
1524 kdb_printf(" %s %s "
1525 kdb_machreg_fmt " "
1526 kdb_machreg_fmt " "
1527 kdb_machreg_fmt, symtab.mod_name,
1528 symtab.sec_name, symtab.sec_start,
1529 symtab.sym_start, symtab.sym_end);
1530 }
1531 addr += bytesperword;
1532 } else {
1533 union {
1534 u64 word;
1535 unsigned char c[8];
1536 } wc;
1537 unsigned char *cp;
1538#ifdef __BIG_ENDIAN
1539 cp = wc.c + 8 - bytesperword;
1540#else
1541 cp = wc.c;
1542#endif
1543 wc.word = word;
1544#define printable_char(c) \
1545 ({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1546 for (j = 0; j < bytesperword; j++)
1547 *c++ = printable_char(*cp++);
1548 addr += bytesperword;
1549#undef printable_char
1550 }
1551 }
1552 kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1553 " ", cbuf);
1554}
1555
1556static int kdb_md(int argc, const char **argv)
1557{
1558 static unsigned long last_addr;
1559 static int last_radix, last_bytesperword, last_repeat;
1560 int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1561 int nosect = 0;
1562 char fmtchar, fmtstr[64];
1563 unsigned long addr;
1564 unsigned long word;
1565 long offset = 0;
1566 int symbolic = 0;
1567 int valid = 0;
1568 int phys = 0;
1569 int raw = 0;
1570
1571 kdbgetintenv("MDCOUNT", &mdcount);
1572 kdbgetintenv("RADIX", &radix);
1573 kdbgetintenv("BYTESPERWORD", &bytesperword);
1574
1575 /* Assume 'md <addr>' and start with environment values */
1576 repeat = mdcount * 16 / bytesperword;
1577
1578 if (strcmp(argv[0], "mdr") == 0) {
1579 if (argc == 2 || (argc == 0 && last_addr != 0))
1580 valid = raw = 1;
1581 else
1582 return KDB_ARGCOUNT;
1583 } else if (isdigit(argv[0][2])) {
1584 bytesperword = (int)(argv[0][2] - '0');
1585 if (bytesperword == 0) {
1586 bytesperword = last_bytesperword;
1587 if (bytesperword == 0)
1588 bytesperword = 4;
1589 }
1590 last_bytesperword = bytesperword;
1591 repeat = mdcount * 16 / bytesperword;
1592 if (!argv[0][3])
1593 valid = 1;
1594 else if (argv[0][3] == 'c' && argv[0][4]) {
1595 if (kstrtouint(argv[0] + 4, 10, &repeat))
1596 return KDB_BADINT;
1597 mdcount = ((repeat * bytesperword) + 15) / 16;
1598 valid = 1;
1599 }
1600 last_repeat = repeat;
1601 } else if (strcmp(argv[0], "md") == 0)
1602 valid = 1;
1603 else if (strcmp(argv[0], "mds") == 0)
1604 valid = 1;
1605 else if (strcmp(argv[0], "mdp") == 0) {
1606 phys = valid = 1;
1607 }
1608 if (!valid)
1609 return KDB_NOTFOUND;
1610
1611 if (argc == 0) {
1612 if (last_addr == 0)
1613 return KDB_ARGCOUNT;
1614 addr = last_addr;
1615 radix = last_radix;
1616 bytesperword = last_bytesperword;
1617 repeat = last_repeat;
1618 if (raw)
1619 mdcount = repeat;
1620 else
1621 mdcount = ((repeat * bytesperword) + 15) / 16;
1622 }
1623
1624 if (argc) {
1625 unsigned long val;
1626 int diag, nextarg = 1;
1627 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1628 &offset, NULL);
1629 if (diag)
1630 return diag;
1631 if (argc > nextarg+2)
1632 return KDB_ARGCOUNT;
1633
1634 if (argc >= nextarg) {
1635 diag = kdbgetularg(argv[nextarg], &val);
1636 if (!diag) {
1637 mdcount = (int) val;
1638 if (raw)
1639 repeat = mdcount;
1640 else
1641 repeat = mdcount * 16 / bytesperword;
1642 }
1643 }
1644 if (argc >= nextarg+1) {
1645 diag = kdbgetularg(argv[nextarg+1], &val);
1646 if (!diag)
1647 radix = (int) val;
1648 }
1649 }
1650
1651 if (strcmp(argv[0], "mdr") == 0) {
1652 int ret;
1653 last_addr = addr;
1654 ret = kdb_mdr(addr, mdcount);
1655 last_addr += mdcount;
1656 last_repeat = mdcount;
1657 last_bytesperword = bytesperword; // to make REPEAT happy
1658 return ret;
1659 }
1660
1661 switch (radix) {
1662 case 10:
1663 fmtchar = 'd';
1664 break;
1665 case 16:
1666 fmtchar = 'x';
1667 break;
1668 case 8:
1669 fmtchar = 'o';
1670 break;
1671 default:
1672 return KDB_BADRADIX;
1673 }
1674
1675 last_radix = radix;
1676
1677 if (bytesperword > KDB_WORD_SIZE)
1678 return KDB_BADWIDTH;
1679
1680 switch (bytesperword) {
1681 case 8:
1682 sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1683 break;
1684 case 4:
1685 sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1686 break;
1687 case 2:
1688 sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1689 break;
1690 case 1:
1691 sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1692 break;
1693 default:
1694 return KDB_BADWIDTH;
1695 }
1696
1697 last_repeat = repeat;
1698 last_bytesperword = bytesperword;
1699
1700 if (strcmp(argv[0], "mds") == 0) {
1701 symbolic = 1;
1702 /* Do not save these changes as last_*, they are temporary mds
1703 * overrides.
1704 */
1705 bytesperword = KDB_WORD_SIZE;
1706 repeat = mdcount;
1707 kdbgetintenv("NOSECT", &nosect);
1708 }
1709
1710 /* Round address down modulo BYTESPERWORD */
1711
1712 addr &= ~(bytesperword-1);
1713
1714 while (repeat > 0) {
1715 unsigned long a;
1716 int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1717
1718 if (KDB_FLAG(CMD_INTERRUPT))
1719 return 0;
1720 for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1721 if (phys) {
1722 if (kdb_getphysword(&word, a, bytesperword)
1723 || word)
1724 break;
1725 } else if (kdb_getword(&word, a, bytesperword) || word)
1726 break;
1727 }
1728 n = min(num, repeat);
1729 kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1730 num, repeat, phys);
1731 addr += bytesperword * n;
1732 repeat -= n;
1733 z = (z + num - 1) / num;
1734 if (z > 2) {
1735 int s = num * (z-2);
1736 kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1737 " zero suppressed\n",
1738 addr, addr + bytesperword * s - 1);
1739 addr += bytesperword * s;
1740 repeat -= s;
1741 }
1742 }
1743 last_addr = addr;
1744
1745 return 0;
1746}
1747
1748/*
1749 * kdb_mm - This function implements the 'mm' command.
1750 * mm address-expression new-value
1751 * Remarks:
1752 * mm works on machine words, mmW works on bytes.
1753 */
1754static int kdb_mm(int argc, const char **argv)
1755{
1756 int diag;
1757 unsigned long addr;
1758 long offset = 0;
1759 unsigned long contents;
1760 int nextarg;
1761 int width;
1762
1763 if (argv[0][2] && !isdigit(argv[0][2]))
1764 return KDB_NOTFOUND;
1765
1766 if (argc < 2)
1767 return KDB_ARGCOUNT;
1768
1769 nextarg = 1;
1770 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1771 if (diag)
1772 return diag;
1773
1774 if (nextarg > argc)
1775 return KDB_ARGCOUNT;
1776 diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1777 if (diag)
1778 return diag;
1779
1780 if (nextarg != argc + 1)
1781 return KDB_ARGCOUNT;
1782
1783 width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1784 diag = kdb_putword(addr, contents, width);
1785 if (diag)
1786 return diag;
1787
1788 kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1789
1790 return 0;
1791}
1792
1793/*
1794 * kdb_go - This function implements the 'go' command.
1795 * go [address-expression]
1796 */
1797static int kdb_go(int argc, const char **argv)
1798{
1799 unsigned long addr;
1800 int diag;
1801 int nextarg;
1802 long offset;
1803
1804 if (raw_smp_processor_id() != kdb_initial_cpu) {
1805 kdb_printf("go must execute on the entry cpu, "
1806 "please use \"cpu %d\" and then execute go\n",
1807 kdb_initial_cpu);
1808 return KDB_BADCPUNUM;
1809 }
1810 if (argc == 1) {
1811 nextarg = 1;
1812 diag = kdbgetaddrarg(argc, argv, &nextarg,
1813 &addr, &offset, NULL);
1814 if (diag)
1815 return diag;
1816 } else if (argc) {
1817 return KDB_ARGCOUNT;
1818 }
1819
1820 diag = KDB_CMD_GO;
1821 if (KDB_FLAG(CATASTROPHIC)) {
1822 kdb_printf("Catastrophic error detected\n");
1823 kdb_printf("kdb_continue_catastrophic=%d, ",
1824 kdb_continue_catastrophic);
1825 if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1826 kdb_printf("type go a second time if you really want "
1827 "to continue\n");
1828 return 0;
1829 }
1830 if (kdb_continue_catastrophic == 2) {
1831 kdb_printf("forcing reboot\n");
1832 kdb_reboot(0, NULL);
1833 }
1834 kdb_printf("attempting to continue\n");
1835 }
1836 return diag;
1837}
1838
1839/*
1840 * kdb_rd - This function implements the 'rd' command.
1841 */
1842static int kdb_rd(int argc, const char **argv)
1843{
1844 int len = kdb_check_regs();
1845#if DBG_MAX_REG_NUM > 0
1846 int i;
1847 char *rname;
1848 int rsize;
1849 u64 reg64;
1850 u32 reg32;
1851 u16 reg16;
1852 u8 reg8;
1853
1854 if (len)
1855 return len;
1856
1857 for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1858 rsize = dbg_reg_def[i].size * 2;
1859 if (rsize > 16)
1860 rsize = 2;
1861 if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1862 len = 0;
1863 kdb_printf("\n");
1864 }
1865 if (len)
1866 len += kdb_printf(" ");
1867 switch(dbg_reg_def[i].size * 8) {
1868 case 8:
1869 rname = dbg_get_reg(i, ®8, kdb_current_regs);
1870 if (!rname)
1871 break;
1872 len += kdb_printf("%s: %02x", rname, reg8);
1873 break;
1874 case 16:
1875 rname = dbg_get_reg(i, ®16, kdb_current_regs);
1876 if (!rname)
1877 break;
1878 len += kdb_printf("%s: %04x", rname, reg16);
1879 break;
1880 case 32:
1881 rname = dbg_get_reg(i, ®32, kdb_current_regs);
1882 if (!rname)
1883 break;
1884 len += kdb_printf("%s: %08x", rname, reg32);
1885 break;
1886 case 64:
1887 rname = dbg_get_reg(i, ®64, kdb_current_regs);
1888 if (!rname)
1889 break;
1890 len += kdb_printf("%s: %016llx", rname, reg64);
1891 break;
1892 default:
1893 len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1894 }
1895 }
1896 kdb_printf("\n");
1897#else
1898 if (len)
1899 return len;
1900
1901 kdb_dumpregs(kdb_current_regs);
1902#endif
1903 return 0;
1904}
1905
1906/*
1907 * kdb_rm - This function implements the 'rm' (register modify) command.
1908 * rm register-name new-contents
1909 * Remarks:
1910 * Allows register modification with the same restrictions as gdb
1911 */
1912static int kdb_rm(int argc, const char **argv)
1913{
1914#if DBG_MAX_REG_NUM > 0
1915 int diag;
1916 const char *rname;
1917 int i;
1918 u64 reg64;
1919 u32 reg32;
1920 u16 reg16;
1921 u8 reg8;
1922
1923 if (argc != 2)
1924 return KDB_ARGCOUNT;
1925 /*
1926 * Allow presence or absence of leading '%' symbol.
1927 */
1928 rname = argv[1];
1929 if (*rname == '%')
1930 rname++;
1931
1932 diag = kdbgetu64arg(argv[2], ®64);
1933 if (diag)
1934 return diag;
1935
1936 diag = kdb_check_regs();
1937 if (diag)
1938 return diag;
1939
1940 diag = KDB_BADREG;
1941 for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1942 if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1943 diag = 0;
1944 break;
1945 }
1946 }
1947 if (!diag) {
1948 switch(dbg_reg_def[i].size * 8) {
1949 case 8:
1950 reg8 = reg64;
1951 dbg_set_reg(i, ®8, kdb_current_regs);
1952 break;
1953 case 16:
1954 reg16 = reg64;
1955 dbg_set_reg(i, ®16, kdb_current_regs);
1956 break;
1957 case 32:
1958 reg32 = reg64;
1959 dbg_set_reg(i, ®32, kdb_current_regs);
1960 break;
1961 case 64:
1962 dbg_set_reg(i, ®64, kdb_current_regs);
1963 break;
1964 }
1965 }
1966 return diag;
1967#else
1968 kdb_printf("ERROR: Register set currently not implemented\n");
1969 return 0;
1970#endif
1971}
1972
1973#if defined(CONFIG_MAGIC_SYSRQ)
1974/*
1975 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1976 * which interfaces to the soi-disant MAGIC SYSRQ functionality.
1977 * sr <magic-sysrq-code>
1978 */
1979static int kdb_sr(int argc, const char **argv)
1980{
1981 bool check_mask =
1982 !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1983
1984 if (argc != 1)
1985 return KDB_ARGCOUNT;
1986
1987 kdb_trap_printk++;
1988 __handle_sysrq(*argv[1], check_mask);
1989 kdb_trap_printk--;
1990
1991 return 0;
1992}
1993#endif /* CONFIG_MAGIC_SYSRQ */
1994
1995/*
1996 * kdb_ef - This function implements the 'regs' (display exception
1997 * frame) command. This command takes an address and expects to
1998 * find an exception frame at that address, formats and prints
1999 * it.
2000 * regs address-expression
2001 * Remarks:
2002 * Not done yet.
2003 */
2004static int kdb_ef(int argc, const char **argv)
2005{
2006 int diag;
2007 unsigned long addr;
2008 long offset;
2009 int nextarg;
2010
2011 if (argc != 1)
2012 return KDB_ARGCOUNT;
2013
2014 nextarg = 1;
2015 diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2016 if (diag)
2017 return diag;
2018 show_regs((struct pt_regs *)addr);
2019 return 0;
2020}
2021
2022/*
2023 * kdb_env - This function implements the 'env' command. Display the
2024 * current environment variables.
2025 */
2026
2027static int kdb_env(int argc, const char **argv)
2028{
2029 kdb_printenv();
2030
2031 if (KDB_DEBUG(MASK))
2032 kdb_printf("KDBDEBUG=0x%x\n",
2033 (kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2034
2035 return 0;
2036}
2037
2038#ifdef CONFIG_PRINTK
2039/*
2040 * kdb_dmesg - This function implements the 'dmesg' command to display
2041 * the contents of the syslog buffer.
2042 * dmesg [lines] [adjust]
2043 */
2044static int kdb_dmesg(int argc, const char **argv)
2045{
2046 int diag;
2047 int logging;
2048 int lines = 0;
2049 int adjust = 0;
2050 int n = 0;
2051 int skip = 0;
2052 struct kmsg_dump_iter iter;
2053 size_t len;
2054 char buf[201];
2055
2056 if (argc > 2)
2057 return KDB_ARGCOUNT;
2058 if (argc) {
2059 if (kstrtoint(argv[1], 0, &lines))
2060 lines = 0;
2061 if (argc > 1 && (kstrtoint(argv[2], 0, &adjust) || adjust < 0))
2062 adjust = 0;
2063 }
2064
2065 /* disable LOGGING if set */
2066 diag = kdbgetintenv("LOGGING", &logging);
2067 if (!diag && logging) {
2068 const char *setargs[] = { "set", "LOGGING", "0" };
2069 kdb_set(2, setargs);
2070 }
2071
2072 kmsg_dump_rewind(&iter);
2073 while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2074 n++;
2075
2076 if (lines < 0) {
2077 if (adjust >= n)
2078 kdb_printf("buffer only contains %d lines, nothing "
2079 "printed\n", n);
2080 else if (adjust - lines >= n)
2081 kdb_printf("buffer only contains %d lines, last %d "
2082 "lines printed\n", n, n - adjust);
2083 skip = adjust;
2084 lines = abs(lines);
2085 } else if (lines > 0) {
2086 skip = n - lines - adjust;
2087 lines = abs(lines);
2088 if (adjust >= n) {
2089 kdb_printf("buffer only contains %d lines, "
2090 "nothing printed\n", n);
2091 skip = n;
2092 } else if (skip < 0) {
2093 lines += skip;
2094 skip = 0;
2095 kdb_printf("buffer only contains %d lines, first "
2096 "%d lines printed\n", n, lines);
2097 }
2098 } else {
2099 lines = n;
2100 }
2101
2102 if (skip >= n || skip < 0)
2103 return 0;
2104
2105 kmsg_dump_rewind(&iter);
2106 while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2107 if (skip) {
2108 skip--;
2109 continue;
2110 }
2111 if (!lines--)
2112 break;
2113 if (KDB_FLAG(CMD_INTERRUPT))
2114 return 0;
2115
2116 kdb_printf("%.*s\n", (int)len - 1, buf);
2117 }
2118
2119 return 0;
2120}
2121#endif /* CONFIG_PRINTK */
2122
2123/* Make sure we balance enable/disable calls, must disable first. */
2124static atomic_t kdb_nmi_disabled;
2125
2126static int kdb_disable_nmi(int argc, const char *argv[])
2127{
2128 if (atomic_read(&kdb_nmi_disabled))
2129 return 0;
2130 atomic_set(&kdb_nmi_disabled, 1);
2131 arch_kgdb_ops.enable_nmi(0);
2132 return 0;
2133}
2134
2135static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2136{
2137 if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2138 return -EINVAL;
2139 arch_kgdb_ops.enable_nmi(1);
2140 return 0;
2141}
2142
2143static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2144 .set = kdb_param_enable_nmi,
2145};
2146module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2147
2148/*
2149 * kdb_cpu - This function implements the 'cpu' command.
2150 * cpu [<cpunum>]
2151 * Returns:
2152 * KDB_CMD_CPU for success, a kdb diagnostic if error
2153 */
2154static void kdb_cpu_status(void)
2155{
2156 int i, start_cpu, first_print = 1;
2157 char state, prev_state = '?';
2158
2159 kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2160 kdb_printf("Available cpus: ");
2161 for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2162 if (!cpu_online(i)) {
2163 state = 'F'; /* cpu is offline */
2164 } else if (!kgdb_info[i].enter_kgdb) {
2165 state = 'D'; /* cpu is online but unresponsive */
2166 } else {
2167 state = ' '; /* cpu is responding to kdb */
2168 if (kdb_task_state_char(KDB_TSK(i)) == '-')
2169 state = '-'; /* idle task */
2170 }
2171 if (state != prev_state) {
2172 if (prev_state != '?') {
2173 if (!first_print)
2174 kdb_printf(", ");
2175 first_print = 0;
2176 kdb_printf("%d", start_cpu);
2177 if (start_cpu < i-1)
2178 kdb_printf("-%d", i-1);
2179 if (prev_state != ' ')
2180 kdb_printf("(%c)", prev_state);
2181 }
2182 prev_state = state;
2183 start_cpu = i;
2184 }
2185 }
2186 /* print the trailing cpus, ignoring them if they are all offline */
2187 if (prev_state != 'F') {
2188 if (!first_print)
2189 kdb_printf(", ");
2190 kdb_printf("%d", start_cpu);
2191 if (start_cpu < i-1)
2192 kdb_printf("-%d", i-1);
2193 if (prev_state != ' ')
2194 kdb_printf("(%c)", prev_state);
2195 }
2196 kdb_printf("\n");
2197}
2198
2199static int kdb_cpu(int argc, const char **argv)
2200{
2201 unsigned long cpunum;
2202 int diag;
2203
2204 if (argc == 0) {
2205 kdb_cpu_status();
2206 return 0;
2207 }
2208
2209 if (argc != 1)
2210 return KDB_ARGCOUNT;
2211
2212 diag = kdbgetularg(argv[1], &cpunum);
2213 if (diag)
2214 return diag;
2215
2216 /*
2217 * Validate cpunum
2218 */
2219 if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2220 return KDB_BADCPUNUM;
2221
2222 dbg_switch_cpu = cpunum;
2223
2224 /*
2225 * Switch to other cpu
2226 */
2227 return KDB_CMD_CPU;
2228}
2229
2230/* The user may not realize that ps/bta with no parameters does not print idle
2231 * or sleeping system daemon processes, so tell them how many were suppressed.
2232 */
2233void kdb_ps_suppressed(void)
2234{
2235 int idle = 0, daemon = 0;
2236 unsigned long cpu;
2237 const struct task_struct *p, *g;
2238 for_each_online_cpu(cpu) {
2239 p = curr_task(cpu);
2240 if (kdb_task_state(p, "-"))
2241 ++idle;
2242 }
2243 for_each_process_thread(g, p) {
2244 if (kdb_task_state(p, "ims"))
2245 ++daemon;
2246 }
2247 if (idle || daemon) {
2248 if (idle)
2249 kdb_printf("%d idle process%s (state -)%s\n",
2250 idle, idle == 1 ? "" : "es",
2251 daemon ? " and " : "");
2252 if (daemon)
2253 kdb_printf("%d sleeping system daemon (state [ims]) "
2254 "process%s", daemon,
2255 daemon == 1 ? "" : "es");
2256 kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2257 }
2258}
2259
2260void kdb_ps1(const struct task_struct *p)
2261{
2262 int cpu;
2263 unsigned long tmp;
2264
2265 if (!p ||
2266 copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2267 return;
2268
2269 cpu = kdb_process_cpu(p);
2270 kdb_printf("0x%px %8d %8d %d %4d %c 0x%px %c%s\n",
2271 (void *)p, p->pid, p->parent->pid,
2272 kdb_task_has_cpu(p), kdb_process_cpu(p),
2273 kdb_task_state_char(p),
2274 (void *)(&p->thread),
2275 p == curr_task(raw_smp_processor_id()) ? '*' : ' ',
2276 p->comm);
2277 if (kdb_task_has_cpu(p)) {
2278 if (!KDB_TSK(cpu)) {
2279 kdb_printf(" Error: no saved data for this cpu\n");
2280 } else {
2281 if (KDB_TSK(cpu) != p)
2282 kdb_printf(" Error: does not match running "
2283 "process table (0x%px)\n", KDB_TSK(cpu));
2284 }
2285 }
2286}
2287
2288/*
2289 * kdb_ps - This function implements the 'ps' command which shows a
2290 * list of the active processes.
2291 *
2292 * ps [<state_chars>] Show processes, optionally selecting only those whose
2293 * state character is found in <state_chars>.
2294 */
2295static int kdb_ps(int argc, const char **argv)
2296{
2297 struct task_struct *g, *p;
2298 const char *mask;
2299 unsigned long cpu;
2300
2301 if (argc == 0)
2302 kdb_ps_suppressed();
2303 kdb_printf("%-*s Pid Parent [*] cpu State %-*s Command\n",
2304 (int)(2*sizeof(void *))+2, "Task Addr",
2305 (int)(2*sizeof(void *))+2, "Thread");
2306 mask = argc ? argv[1] : kdbgetenv("PS");
2307 /* Run the active tasks first */
2308 for_each_online_cpu(cpu) {
2309 if (KDB_FLAG(CMD_INTERRUPT))
2310 return 0;
2311 p = curr_task(cpu);
2312 if (kdb_task_state(p, mask))
2313 kdb_ps1(p);
2314 }
2315 kdb_printf("\n");
2316 /* Now the real tasks */
2317 for_each_process_thread(g, p) {
2318 if (KDB_FLAG(CMD_INTERRUPT))
2319 return 0;
2320 if (kdb_task_state(p, mask))
2321 kdb_ps1(p);
2322 }
2323
2324 return 0;
2325}
2326
2327/*
2328 * kdb_pid - This function implements the 'pid' command which switches
2329 * the currently active process.
2330 * pid [<pid> | R]
2331 */
2332static int kdb_pid(int argc, const char **argv)
2333{
2334 struct task_struct *p;
2335 unsigned long val;
2336 int diag;
2337
2338 if (argc > 1)
2339 return KDB_ARGCOUNT;
2340
2341 if (argc) {
2342 if (strcmp(argv[1], "R") == 0) {
2343 p = KDB_TSK(kdb_initial_cpu);
2344 } else {
2345 diag = kdbgetularg(argv[1], &val);
2346 if (diag)
2347 return KDB_BADINT;
2348
2349 p = find_task_by_pid_ns((pid_t)val, &init_pid_ns);
2350 if (!p) {
2351 kdb_printf("No task with pid=%d\n", (pid_t)val);
2352 return 0;
2353 }
2354 }
2355 kdb_set_current_task(p);
2356 }
2357 kdb_printf("KDB current process is %s(pid=%d)\n",
2358 kdb_current_task->comm,
2359 kdb_current_task->pid);
2360
2361 return 0;
2362}
2363
2364static int kdb_kgdb(int argc, const char **argv)
2365{
2366 return KDB_CMD_KGDB;
2367}
2368
2369/*
2370 * kdb_help - This function implements the 'help' and '?' commands.
2371 */
2372static int kdb_help(int argc, const char **argv)
2373{
2374 kdbtab_t *kt;
2375
2376 kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2377 kdb_printf("-----------------------------"
2378 "-----------------------------\n");
2379 list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2380 char *space = "";
2381 if (KDB_FLAG(CMD_INTERRUPT))
2382 return 0;
2383 if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true))
2384 continue;
2385 if (strlen(kt->usage) > 20)
2386 space = "\n ";
2387 kdb_printf("%-15.15s %-20s%s%s\n", kt->name,
2388 kt->usage, space, kt->help);
2389 }
2390 return 0;
2391}
2392
2393/*
2394 * kdb_kill - This function implements the 'kill' commands.
2395 */
2396static int kdb_kill(int argc, const char **argv)
2397{
2398 long sig, pid;
2399 struct task_struct *p;
2400
2401 if (argc != 2)
2402 return KDB_ARGCOUNT;
2403
2404 if (kstrtol(argv[1], 0, &sig))
2405 return KDB_BADINT;
2406 if ((sig >= 0) || !valid_signal(-sig)) {
2407 kdb_printf("Invalid signal parameter.<-signal>\n");
2408 return 0;
2409 }
2410 sig = -sig;
2411
2412 if (kstrtol(argv[2], 0, &pid))
2413 return KDB_BADINT;
2414 if (pid <= 0) {
2415 kdb_printf("Process ID must be large than 0.\n");
2416 return 0;
2417 }
2418
2419 /* Find the process. */
2420 p = find_task_by_pid_ns(pid, &init_pid_ns);
2421 if (!p) {
2422 kdb_printf("The specified process isn't found.\n");
2423 return 0;
2424 }
2425 p = p->group_leader;
2426 kdb_send_sig(p, sig);
2427 return 0;
2428}
2429
2430/*
2431 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2432 * I cannot call that code directly from kdb, it has an unconditional
2433 * cli()/sti() and calls routines that take locks which can stop the debugger.
2434 */
2435static void kdb_sysinfo(struct sysinfo *val)
2436{
2437 u64 uptime = ktime_get_mono_fast_ns();
2438
2439 memset(val, 0, sizeof(*val));
2440 val->uptime = div_u64(uptime, NSEC_PER_SEC);
2441 val->loads[0] = avenrun[0];
2442 val->loads[1] = avenrun[1];
2443 val->loads[2] = avenrun[2];
2444 val->procs = nr_threads-1;
2445 si_meminfo(val);
2446
2447 return;
2448}
2449
2450/*
2451 * kdb_summary - This function implements the 'summary' command.
2452 */
2453static int kdb_summary(int argc, const char **argv)
2454{
2455 time64_t now;
2456 struct sysinfo val;
2457
2458 if (argc)
2459 return KDB_ARGCOUNT;
2460
2461 kdb_printf("sysname %s\n", init_uts_ns.name.sysname);
2462 kdb_printf("release %s\n", init_uts_ns.name.release);
2463 kdb_printf("version %s\n", init_uts_ns.name.version);
2464 kdb_printf("machine %s\n", init_uts_ns.name.machine);
2465 kdb_printf("nodename %s\n", init_uts_ns.name.nodename);
2466 kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2467
2468 now = __ktime_get_real_seconds();
2469 kdb_printf("date %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
2470 kdb_sysinfo(&val);
2471 kdb_printf("uptime ");
2472 if (val.uptime > (24*60*60)) {
2473 int days = val.uptime / (24*60*60);
2474 val.uptime %= (24*60*60);
2475 kdb_printf("%d day%s ", days, str_plural(days));
2476 }
2477 kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2478
2479 kdb_printf("load avg %ld.%02ld %ld.%02ld %ld.%02ld\n",
2480 LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2481 LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2482 LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2483
2484 /* Display in kilobytes */
2485#define K(x) ((x) << (PAGE_SHIFT - 10))
2486 kdb_printf("\nMemTotal: %8lu kB\nMemFree: %8lu kB\n"
2487 "Buffers: %8lu kB\n",
2488 K(val.totalram), K(val.freeram), K(val.bufferram));
2489 return 0;
2490}
2491
2492/*
2493 * kdb_per_cpu - This function implements the 'per_cpu' command.
2494 */
2495static int kdb_per_cpu(int argc, const char **argv)
2496{
2497 char fmtstr[64];
2498 int cpu, diag, nextarg = 1;
2499 unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2500
2501 if (argc < 1 || argc > 3)
2502 return KDB_ARGCOUNT;
2503
2504 diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2505 if (diag)
2506 return diag;
2507
2508 if (argc >= 2) {
2509 diag = kdbgetularg(argv[2], &bytesperword);
2510 if (diag)
2511 return diag;
2512 }
2513 if (!bytesperword)
2514 bytesperword = KDB_WORD_SIZE;
2515 else if (bytesperword > KDB_WORD_SIZE)
2516 return KDB_BADWIDTH;
2517 sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2518 if (argc >= 3) {
2519 diag = kdbgetularg(argv[3], &whichcpu);
2520 if (diag)
2521 return diag;
2522 if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2523 kdb_printf("cpu %ld is not online\n", whichcpu);
2524 return KDB_BADCPUNUM;
2525 }
2526 }
2527
2528 /* Most architectures use __per_cpu_offset[cpu], some use
2529 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2530 */
2531#ifdef __per_cpu_offset
2532#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2533#else
2534#ifdef CONFIG_SMP
2535#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2536#else
2537#define KDB_PCU(cpu) 0
2538#endif
2539#endif
2540 for_each_online_cpu(cpu) {
2541 if (KDB_FLAG(CMD_INTERRUPT))
2542 return 0;
2543
2544 if (whichcpu != ~0UL && whichcpu != cpu)
2545 continue;
2546 addr = symaddr + KDB_PCU(cpu);
2547 diag = kdb_getword(&val, addr, bytesperword);
2548 if (diag) {
2549 kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2550 "read, diag=%d\n", cpu, addr, diag);
2551 continue;
2552 }
2553 kdb_printf("%5d ", cpu);
2554 kdb_md_line(fmtstr, addr,
2555 bytesperword == KDB_WORD_SIZE,
2556 1, bytesperword, 1, 1, 0);
2557 }
2558#undef KDB_PCU
2559 return 0;
2560}
2561
2562/*
2563 * display help for the use of cmd | grep pattern
2564 */
2565static int kdb_grep_help(int argc, const char **argv)
2566{
2567 kdb_printf("Usage of cmd args | grep pattern:\n");
2568 kdb_printf(" Any command's output may be filtered through an ");
2569 kdb_printf("emulated 'pipe'.\n");
2570 kdb_printf(" 'grep' is just a key word.\n");
2571 kdb_printf(" The pattern may include a very limited set of "
2572 "metacharacters:\n");
2573 kdb_printf(" pattern or ^pattern or pattern$ or ^pattern$\n");
2574 kdb_printf(" And if there are spaces in the pattern, you may "
2575 "quote it:\n");
2576 kdb_printf(" \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2577 " or \"^pat tern$\"\n");
2578 return 0;
2579}
2580
2581/**
2582 * kdb_register() - This function is used to register a kernel debugger
2583 * command.
2584 * @cmd: pointer to kdb command
2585 *
2586 * Note that it's the job of the caller to keep the memory for the cmd
2587 * allocated until unregister is called.
2588 */
2589int kdb_register(kdbtab_t *cmd)
2590{
2591 kdbtab_t *kp;
2592
2593 list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2594 if (strcmp(kp->name, cmd->name) == 0) {
2595 kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
2596 cmd->name, cmd->func, cmd->help);
2597 return 1;
2598 }
2599 }
2600
2601 list_add_tail(&cmd->list_node, &kdb_cmds_head);
2602 return 0;
2603}
2604EXPORT_SYMBOL_GPL(kdb_register);
2605
2606/**
2607 * kdb_register_table() - This function is used to register a kdb command
2608 * table.
2609 * @kp: pointer to kdb command table
2610 * @len: length of kdb command table
2611 */
2612void kdb_register_table(kdbtab_t *kp, size_t len)
2613{
2614 while (len--) {
2615 list_add_tail(&kp->list_node, &kdb_cmds_head);
2616 kp++;
2617 }
2618}
2619
2620/**
2621 * kdb_unregister() - This function is used to unregister a kernel debugger
2622 * command. It is generally called when a module which
2623 * implements kdb command is unloaded.
2624 * @cmd: pointer to kdb command
2625 */
2626void kdb_unregister(kdbtab_t *cmd)
2627{
2628 list_del(&cmd->list_node);
2629}
2630EXPORT_SYMBOL_GPL(kdb_unregister);
2631
2632static kdbtab_t maintab[] = {
2633 { .name = "md",
2634 .func = kdb_md,
2635 .usage = "<vaddr>",
2636 .help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2637 .minlen = 1,
2638 .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2639 },
2640 { .name = "mdr",
2641 .func = kdb_md,
2642 .usage = "<vaddr> <bytes>",
2643 .help = "Display Raw Memory",
2644 .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2645 },
2646 { .name = "mdp",
2647 .func = kdb_md,
2648 .usage = "<paddr> <bytes>",
2649 .help = "Display Physical Memory",
2650 .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2651 },
2652 { .name = "mds",
2653 .func = kdb_md,
2654 .usage = "<vaddr>",
2655 .help = "Display Memory Symbolically",
2656 .flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2657 },
2658 { .name = "mm",
2659 .func = kdb_mm,
2660 .usage = "<vaddr> <contents>",
2661 .help = "Modify Memory Contents",
2662 .flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2663 },
2664 { .name = "go",
2665 .func = kdb_go,
2666 .usage = "[<vaddr>]",
2667 .help = "Continue Execution",
2668 .minlen = 1,
2669 .flags = KDB_ENABLE_REG_WRITE |
2670 KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2671 },
2672 { .name = "rd",
2673 .func = kdb_rd,
2674 .usage = "",
2675 .help = "Display Registers",
2676 .flags = KDB_ENABLE_REG_READ,
2677 },
2678 { .name = "rm",
2679 .func = kdb_rm,
2680 .usage = "<reg> <contents>",
2681 .help = "Modify Registers",
2682 .flags = KDB_ENABLE_REG_WRITE,
2683 },
2684 { .name = "ef",
2685 .func = kdb_ef,
2686 .usage = "<vaddr>",
2687 .help = "Display exception frame",
2688 .flags = KDB_ENABLE_MEM_READ,
2689 },
2690 { .name = "bt",
2691 .func = kdb_bt,
2692 .usage = "[<vaddr>]",
2693 .help = "Stack traceback",
2694 .minlen = 1,
2695 .flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2696 },
2697 { .name = "btp",
2698 .func = kdb_bt,
2699 .usage = "<pid>",
2700 .help = "Display stack for process <pid>",
2701 .flags = KDB_ENABLE_INSPECT,
2702 },
2703 { .name = "bta",
2704 .func = kdb_bt,
2705 .usage = "[<state_chars>|A]",
2706 .help = "Backtrace all processes whose state matches",
2707 .flags = KDB_ENABLE_INSPECT,
2708 },
2709 { .name = "btc",
2710 .func = kdb_bt,
2711 .usage = "",
2712 .help = "Backtrace current process on each cpu",
2713 .flags = KDB_ENABLE_INSPECT,
2714 },
2715 { .name = "btt",
2716 .func = kdb_bt,
2717 .usage = "<vaddr>",
2718 .help = "Backtrace process given its struct task address",
2719 .flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2720 },
2721 { .name = "env",
2722 .func = kdb_env,
2723 .usage = "",
2724 .help = "Show environment variables",
2725 .flags = KDB_ENABLE_ALWAYS_SAFE,
2726 },
2727 { .name = "set",
2728 .func = kdb_set,
2729 .usage = "",
2730 .help = "Set environment variables",
2731 .flags = KDB_ENABLE_ALWAYS_SAFE,
2732 },
2733 { .name = "help",
2734 .func = kdb_help,
2735 .usage = "",
2736 .help = "Display Help Message",
2737 .minlen = 1,
2738 .flags = KDB_ENABLE_ALWAYS_SAFE,
2739 },
2740 { .name = "?",
2741 .func = kdb_help,
2742 .usage = "",
2743 .help = "Display Help Message",
2744 .flags = KDB_ENABLE_ALWAYS_SAFE,
2745 },
2746 { .name = "cpu",
2747 .func = kdb_cpu,
2748 .usage = "<cpunum>",
2749 .help = "Switch to new cpu",
2750 .flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2751 },
2752 { .name = "kgdb",
2753 .func = kdb_kgdb,
2754 .usage = "",
2755 .help = "Enter kgdb mode",
2756 .flags = 0,
2757 },
2758 { .name = "ps",
2759 .func = kdb_ps,
2760 .usage = "[<state_chars>|A]",
2761 .help = "Display active task list",
2762 .flags = KDB_ENABLE_INSPECT,
2763 },
2764 { .name = "pid",
2765 .func = kdb_pid,
2766 .usage = "<pidnum>",
2767 .help = "Switch to another task",
2768 .flags = KDB_ENABLE_INSPECT,
2769 },
2770 { .name = "reboot",
2771 .func = kdb_reboot,
2772 .usage = "",
2773 .help = "Reboot the machine immediately",
2774 .flags = KDB_ENABLE_REBOOT,
2775 },
2776#if defined(CONFIG_MODULES)
2777 { .name = "lsmod",
2778 .func = kdb_lsmod,
2779 .usage = "",
2780 .help = "List loaded kernel modules",
2781 .flags = KDB_ENABLE_INSPECT,
2782 },
2783#endif
2784#if defined(CONFIG_MAGIC_SYSRQ)
2785 { .name = "sr",
2786 .func = kdb_sr,
2787 .usage = "<key>",
2788 .help = "Magic SysRq key",
2789 .flags = KDB_ENABLE_ALWAYS_SAFE,
2790 },
2791#endif
2792#if defined(CONFIG_PRINTK)
2793 { .name = "dmesg",
2794 .func = kdb_dmesg,
2795 .usage = "[lines]",
2796 .help = "Display syslog buffer",
2797 .flags = KDB_ENABLE_ALWAYS_SAFE,
2798 },
2799#endif
2800 { .name = "defcmd",
2801 .func = kdb_defcmd,
2802 .usage = "name \"usage\" \"help\"",
2803 .help = "Define a set of commands, down to endefcmd",
2804 /*
2805 * Macros are always safe because when executed each
2806 * internal command re-enters kdb_parse() and is safety
2807 * checked individually.
2808 */
2809 .flags = KDB_ENABLE_ALWAYS_SAFE,
2810 },
2811 { .name = "kill",
2812 .func = kdb_kill,
2813 .usage = "<-signal> <pid>",
2814 .help = "Send a signal to a process",
2815 .flags = KDB_ENABLE_SIGNAL,
2816 },
2817 { .name = "summary",
2818 .func = kdb_summary,
2819 .usage = "",
2820 .help = "Summarize the system",
2821 .minlen = 4,
2822 .flags = KDB_ENABLE_ALWAYS_SAFE,
2823 },
2824 { .name = "per_cpu",
2825 .func = kdb_per_cpu,
2826 .usage = "<sym> [<bytes>] [<cpu>]",
2827 .help = "Display per_cpu variables",
2828 .minlen = 3,
2829 .flags = KDB_ENABLE_MEM_READ,
2830 },
2831 { .name = "grephelp",
2832 .func = kdb_grep_help,
2833 .usage = "",
2834 .help = "Display help on | grep",
2835 .flags = KDB_ENABLE_ALWAYS_SAFE,
2836 },
2837};
2838
2839static kdbtab_t nmicmd = {
2840 .name = "disable_nmi",
2841 .func = kdb_disable_nmi,
2842 .usage = "",
2843 .help = "Disable NMI entry to KDB",
2844 .flags = KDB_ENABLE_ALWAYS_SAFE,
2845};
2846
2847/* Initialize the kdb command table. */
2848static void __init kdb_inittab(void)
2849{
2850 kdb_register_table(maintab, ARRAY_SIZE(maintab));
2851 if (arch_kgdb_ops.enable_nmi)
2852 kdb_register_table(&nmicmd, 1);
2853}
2854
2855/* Execute any commands defined in kdb_cmds. */
2856static void __init kdb_cmd_init(void)
2857{
2858 int i, diag;
2859 for (i = 0; kdb_cmds[i]; ++i) {
2860 diag = kdb_parse(kdb_cmds[i]);
2861 if (diag)
2862 kdb_printf("kdb command %s failed, kdb diag %d\n",
2863 kdb_cmds[i], diag);
2864 }
2865 if (defcmd_in_progress) {
2866 kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2867 kdb_parse("endefcmd");
2868 }
2869}
2870
2871/* Initialize kdb_printf, breakpoint tables and kdb state */
2872void __init kdb_init(int lvl)
2873{
2874 static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2875 int i;
2876
2877 if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2878 return;
2879 for (i = kdb_init_lvl; i < lvl; i++) {
2880 switch (i) {
2881 case KDB_NOT_INITIALIZED:
2882 kdb_inittab(); /* Initialize Command Table */
2883 kdb_initbptab(); /* Initialize Breakpoints */
2884 break;
2885 case KDB_INIT_EARLY:
2886 kdb_cmd_init(); /* Build kdb_cmds tables */
2887 break;
2888 }
2889 }
2890 kdb_init_lvl = lvl;
2891}