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v4.17
   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	int 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 int 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 = 0;
 680		if (!s->count)
 681			s->usable = 0;
 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 = kzalloc((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 = 0;
 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((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 = 1;
 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 = 1;
 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 (strncmp(cp, "grep ", 5)) {
 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%p, 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%p, 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	unsigned long word;
1497
1498	memset(cbuf, '\0', sizeof(cbuf));
1499	if (phys)
1500		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1501	else
1502		kdb_printf(kdb_machreg_fmt0 " ", addr);
1503
1504	for (i = 0; i < num && repeat--; i++) {
1505		if (phys) {
1506			if (kdb_getphysword(&word, addr, bytesperword))
1507				break;
1508		} else if (kdb_getword(&word, addr, bytesperword))
1509			break;
1510		kdb_printf(fmtstr, word);
1511		if (symbolic)
1512			kdbnearsym(word, &symtab);
1513		else
1514			memset(&symtab, 0, sizeof(symtab));
1515		if (symtab.sym_name) {
1516			kdb_symbol_print(word, &symtab, 0);
1517			if (!nosect) {
1518				kdb_printf("\n");
1519				kdb_printf("                       %s %s "
1520					   kdb_machreg_fmt " "
1521					   kdb_machreg_fmt " "
1522					   kdb_machreg_fmt, symtab.mod_name,
1523					   symtab.sec_name, symtab.sec_start,
1524					   symtab.sym_start, symtab.sym_end);
1525			}
1526			addr += bytesperword;
1527		} else {
1528			union {
1529				u64 word;
1530				unsigned char c[8];
1531			} wc;
1532			unsigned char *cp;
1533#ifdef	__BIG_ENDIAN
1534			cp = wc.c + 8 - bytesperword;
1535#else
1536			cp = wc.c;
1537#endif
1538			wc.word = word;
1539#define printable_char(c) \
1540	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1541			switch (bytesperword) {
1542			case 8:
1543				*c++ = printable_char(*cp++);
1544				*c++ = printable_char(*cp++);
1545				*c++ = printable_char(*cp++);
1546				*c++ = printable_char(*cp++);
1547				addr += 4;
1548			case 4:
1549				*c++ = printable_char(*cp++);
1550				*c++ = printable_char(*cp++);
1551				addr += 2;
1552			case 2:
1553				*c++ = printable_char(*cp++);
1554				addr++;
1555			case 1:
1556				*c++ = printable_char(*cp++);
1557				addr++;
1558				break;
1559			}
1560#undef printable_char
1561		}
1562	}
1563	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1564		   " ", cbuf);
1565}
1566
1567static int kdb_md(int argc, const char **argv)
1568{
1569	static unsigned long last_addr;
1570	static int last_radix, last_bytesperword, last_repeat;
1571	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1572	int nosect = 0;
1573	char fmtchar, fmtstr[64];
1574	unsigned long addr;
1575	unsigned long word;
1576	long offset = 0;
1577	int symbolic = 0;
1578	int valid = 0;
1579	int phys = 0;
1580	int raw = 0;
1581
1582	kdbgetintenv("MDCOUNT", &mdcount);
1583	kdbgetintenv("RADIX", &radix);
1584	kdbgetintenv("BYTESPERWORD", &bytesperword);
1585
1586	/* Assume 'md <addr>' and start with environment values */
1587	repeat = mdcount * 16 / bytesperword;
1588
1589	if (strcmp(argv[0], "mdr") == 0) {
1590		if (argc == 2 || (argc == 0 && last_addr != 0))
1591			valid = raw = 1;
1592		else
1593			return KDB_ARGCOUNT;
 
1594	} else if (isdigit(argv[0][2])) {
1595		bytesperword = (int)(argv[0][2] - '0');
1596		if (bytesperword == 0) {
1597			bytesperword = last_bytesperword;
1598			if (bytesperword == 0)
1599				bytesperword = 4;
1600		}
1601		last_bytesperword = bytesperword;
1602		repeat = mdcount * 16 / bytesperword;
1603		if (!argv[0][3])
1604			valid = 1;
1605		else if (argv[0][3] == 'c' && argv[0][4]) {
1606			char *p;
1607			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1608			mdcount = ((repeat * bytesperword) + 15) / 16;
1609			valid = !*p;
1610		}
1611		last_repeat = repeat;
1612	} else if (strcmp(argv[0], "md") == 0)
1613		valid = 1;
1614	else if (strcmp(argv[0], "mds") == 0)
1615		valid = 1;
1616	else if (strcmp(argv[0], "mdp") == 0) {
1617		phys = valid = 1;
1618	}
1619	if (!valid)
1620		return KDB_NOTFOUND;
1621
1622	if (argc == 0) {
1623		if (last_addr == 0)
1624			return KDB_ARGCOUNT;
1625		addr = last_addr;
1626		radix = last_radix;
1627		bytesperword = last_bytesperword;
1628		repeat = last_repeat;
1629		if (raw)
1630			mdcount = repeat;
1631		else
1632			mdcount = ((repeat * bytesperword) + 15) / 16;
1633	}
1634
1635	if (argc) {
1636		unsigned long val;
1637		int diag, nextarg = 1;
1638		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1639				     &offset, NULL);
1640		if (diag)
1641			return diag;
1642		if (argc > nextarg+2)
1643			return KDB_ARGCOUNT;
1644
1645		if (argc >= nextarg) {
1646			diag = kdbgetularg(argv[nextarg], &val);
1647			if (!diag) {
1648				mdcount = (int) val;
1649				if (raw)
1650					repeat = mdcount;
1651				else
1652					repeat = mdcount * 16 / bytesperword;
1653			}
1654		}
1655		if (argc >= nextarg+1) {
1656			diag = kdbgetularg(argv[nextarg+1], &val);
1657			if (!diag)
1658				radix = (int) val;
1659		}
1660	}
1661
1662	if (strcmp(argv[0], "mdr") == 0) {
1663		int ret;
1664		last_addr = addr;
1665		ret = kdb_mdr(addr, mdcount);
1666		last_addr += mdcount;
1667		last_repeat = mdcount;
1668		last_bytesperword = bytesperword; // to make REPEAT happy
1669		return ret;
1670	}
1671
1672	switch (radix) {
1673	case 10:
1674		fmtchar = 'd';
1675		break;
1676	case 16:
1677		fmtchar = 'x';
1678		break;
1679	case 8:
1680		fmtchar = 'o';
1681		break;
1682	default:
1683		return KDB_BADRADIX;
1684	}
1685
1686	last_radix = radix;
1687
1688	if (bytesperword > KDB_WORD_SIZE)
1689		return KDB_BADWIDTH;
1690
1691	switch (bytesperword) {
1692	case 8:
1693		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1694		break;
1695	case 4:
1696		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1697		break;
1698	case 2:
1699		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1700		break;
1701	case 1:
1702		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1703		break;
1704	default:
1705		return KDB_BADWIDTH;
1706	}
1707
1708	last_repeat = repeat;
1709	last_bytesperword = bytesperword;
1710
1711	if (strcmp(argv[0], "mds") == 0) {
1712		symbolic = 1;
1713		/* Do not save these changes as last_*, they are temporary mds
1714		 * overrides.
1715		 */
1716		bytesperword = KDB_WORD_SIZE;
1717		repeat = mdcount;
1718		kdbgetintenv("NOSECT", &nosect);
1719	}
1720
1721	/* Round address down modulo BYTESPERWORD */
1722
1723	addr &= ~(bytesperword-1);
1724
1725	while (repeat > 0) {
1726		unsigned long a;
1727		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1728
1729		if (KDB_FLAG(CMD_INTERRUPT))
1730			return 0;
1731		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1732			if (phys) {
1733				if (kdb_getphysword(&word, a, bytesperword)
1734						|| word)
1735					break;
1736			} else if (kdb_getword(&word, a, bytesperword) || word)
1737				break;
1738		}
1739		n = min(num, repeat);
1740		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1741			    num, repeat, phys);
1742		addr += bytesperword * n;
1743		repeat -= n;
1744		z = (z + num - 1) / num;
1745		if (z > 2) {
1746			int s = num * (z-2);
1747			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1748				   " zero suppressed\n",
1749				addr, addr + bytesperword * s - 1);
1750			addr += bytesperword * s;
1751			repeat -= s;
1752		}
1753	}
1754	last_addr = addr;
1755
1756	return 0;
1757}
1758
1759/*
1760 * kdb_mm - This function implements the 'mm' command.
1761 *	mm address-expression new-value
1762 * Remarks:
1763 *	mm works on machine words, mmW works on bytes.
1764 */
1765static int kdb_mm(int argc, const char **argv)
1766{
1767	int diag;
1768	unsigned long addr;
1769	long offset = 0;
1770	unsigned long contents;
1771	int nextarg;
1772	int width;
1773
1774	if (argv[0][2] && !isdigit(argv[0][2]))
1775		return KDB_NOTFOUND;
1776
1777	if (argc < 2)
1778		return KDB_ARGCOUNT;
1779
1780	nextarg = 1;
1781	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1782	if (diag)
1783		return diag;
1784
1785	if (nextarg > argc)
1786		return KDB_ARGCOUNT;
1787	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1788	if (diag)
1789		return diag;
1790
1791	if (nextarg != argc + 1)
1792		return KDB_ARGCOUNT;
1793
1794	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1795	diag = kdb_putword(addr, contents, width);
1796	if (diag)
1797		return diag;
1798
1799	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1800
1801	return 0;
1802}
1803
1804/*
1805 * kdb_go - This function implements the 'go' command.
1806 *	go [address-expression]
1807 */
1808static int kdb_go(int argc, const char **argv)
1809{
1810	unsigned long addr;
1811	int diag;
1812	int nextarg;
1813	long offset;
1814
1815	if (raw_smp_processor_id() != kdb_initial_cpu) {
1816		kdb_printf("go must execute on the entry cpu, "
1817			   "please use \"cpu %d\" and then execute go\n",
1818			   kdb_initial_cpu);
1819		return KDB_BADCPUNUM;
1820	}
1821	if (argc == 1) {
1822		nextarg = 1;
1823		diag = kdbgetaddrarg(argc, argv, &nextarg,
1824				     &addr, &offset, NULL);
1825		if (diag)
1826			return diag;
1827	} else if (argc) {
1828		return KDB_ARGCOUNT;
1829	}
1830
1831	diag = KDB_CMD_GO;
1832	if (KDB_FLAG(CATASTROPHIC)) {
1833		kdb_printf("Catastrophic error detected\n");
1834		kdb_printf("kdb_continue_catastrophic=%d, ",
1835			kdb_continue_catastrophic);
1836		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1837			kdb_printf("type go a second time if you really want "
1838				   "to continue\n");
1839			return 0;
1840		}
1841		if (kdb_continue_catastrophic == 2) {
1842			kdb_printf("forcing reboot\n");
1843			kdb_reboot(0, NULL);
1844		}
1845		kdb_printf("attempting to continue\n");
1846	}
1847	return diag;
1848}
1849
1850/*
1851 * kdb_rd - This function implements the 'rd' command.
1852 */
1853static int kdb_rd(int argc, const char **argv)
1854{
1855	int len = kdb_check_regs();
1856#if DBG_MAX_REG_NUM > 0
1857	int i;
1858	char *rname;
1859	int rsize;
1860	u64 reg64;
1861	u32 reg32;
1862	u16 reg16;
1863	u8 reg8;
1864
1865	if (len)
1866		return len;
1867
1868	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1869		rsize = dbg_reg_def[i].size * 2;
1870		if (rsize > 16)
1871			rsize = 2;
1872		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1873			len = 0;
1874			kdb_printf("\n");
1875		}
1876		if (len)
1877			len += kdb_printf("  ");
1878		switch(dbg_reg_def[i].size * 8) {
1879		case 8:
1880			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1881			if (!rname)
1882				break;
1883			len += kdb_printf("%s: %02x", rname, reg8);
1884			break;
1885		case 16:
1886			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1887			if (!rname)
1888				break;
1889			len += kdb_printf("%s: %04x", rname, reg16);
1890			break;
1891		case 32:
1892			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1893			if (!rname)
1894				break;
1895			len += kdb_printf("%s: %08x", rname, reg32);
1896			break;
1897		case 64:
1898			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1899			if (!rname)
1900				break;
1901			len += kdb_printf("%s: %016llx", rname, reg64);
1902			break;
1903		default:
1904			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1905		}
1906	}
1907	kdb_printf("\n");
1908#else
1909	if (len)
1910		return len;
1911
1912	kdb_dumpregs(kdb_current_regs);
1913#endif
1914	return 0;
1915}
1916
1917/*
1918 * kdb_rm - This function implements the 'rm' (register modify)  command.
1919 *	rm register-name new-contents
1920 * Remarks:
1921 *	Allows register modification with the same restrictions as gdb
1922 */
1923static int kdb_rm(int argc, const char **argv)
1924{
1925#if DBG_MAX_REG_NUM > 0
1926	int diag;
1927	const char *rname;
1928	int i;
1929	u64 reg64;
1930	u32 reg32;
1931	u16 reg16;
1932	u8 reg8;
1933
1934	if (argc != 2)
1935		return KDB_ARGCOUNT;
1936	/*
1937	 * Allow presence or absence of leading '%' symbol.
1938	 */
1939	rname = argv[1];
1940	if (*rname == '%')
1941		rname++;
1942
1943	diag = kdbgetu64arg(argv[2], &reg64);
1944	if (diag)
1945		return diag;
1946
1947	diag = kdb_check_regs();
1948	if (diag)
1949		return diag;
1950
1951	diag = KDB_BADREG;
1952	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1953		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1954			diag = 0;
1955			break;
1956		}
1957	}
1958	if (!diag) {
1959		switch(dbg_reg_def[i].size * 8) {
1960		case 8:
1961			reg8 = reg64;
1962			dbg_set_reg(i, &reg8, kdb_current_regs);
1963			break;
1964		case 16:
1965			reg16 = reg64;
1966			dbg_set_reg(i, &reg16, kdb_current_regs);
1967			break;
1968		case 32:
1969			reg32 = reg64;
1970			dbg_set_reg(i, &reg32, kdb_current_regs);
1971			break;
1972		case 64:
1973			dbg_set_reg(i, &reg64, kdb_current_regs);
1974			break;
1975		}
1976	}
1977	return diag;
1978#else
1979	kdb_printf("ERROR: Register set currently not implemented\n");
1980    return 0;
1981#endif
1982}
1983
1984#if defined(CONFIG_MAGIC_SYSRQ)
1985/*
1986 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1987 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1988 *		sr <magic-sysrq-code>
1989 */
1990static int kdb_sr(int argc, const char **argv)
1991{
1992	bool check_mask =
1993	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1994
1995	if (argc != 1)
1996		return KDB_ARGCOUNT;
1997
1998	kdb_trap_printk++;
1999	__handle_sysrq(*argv[1], check_mask);
2000	kdb_trap_printk--;
2001
2002	return 0;
2003}
2004#endif	/* CONFIG_MAGIC_SYSRQ */
2005
2006/*
2007 * kdb_ef - This function implements the 'regs' (display exception
2008 *	frame) command.  This command takes an address and expects to
2009 *	find an exception frame at that address, formats and prints
2010 *	it.
2011 *		regs address-expression
2012 * Remarks:
2013 *	Not done yet.
2014 */
2015static int kdb_ef(int argc, const char **argv)
2016{
2017	int diag;
2018	unsigned long addr;
2019	long offset;
2020	int nextarg;
2021
2022	if (argc != 1)
2023		return KDB_ARGCOUNT;
2024
2025	nextarg = 1;
2026	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2027	if (diag)
2028		return diag;
2029	show_regs((struct pt_regs *)addr);
2030	return 0;
2031}
2032
2033#if defined(CONFIG_MODULES)
2034/*
2035 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2036 *	currently loaded kernel modules.
2037 *	Mostly taken from userland lsmod.
2038 */
2039static int kdb_lsmod(int argc, const char **argv)
2040{
2041	struct module *mod;
2042
2043	if (argc != 0)
2044		return KDB_ARGCOUNT;
2045
2046	kdb_printf("Module                  Size  modstruct     Used by\n");
2047	list_for_each_entry(mod, kdb_modules, list) {
2048		if (mod->state == MODULE_STATE_UNFORMED)
2049			continue;
2050
2051		kdb_printf("%-20s%8u  0x%p ", mod->name,
2052			   mod->core_layout.size, (void *)mod);
2053#ifdef CONFIG_MODULE_UNLOAD
2054		kdb_printf("%4d ", module_refcount(mod));
2055#endif
2056		if (mod->state == MODULE_STATE_GOING)
2057			kdb_printf(" (Unloading)");
2058		else if (mod->state == MODULE_STATE_COMING)
2059			kdb_printf(" (Loading)");
2060		else
2061			kdb_printf(" (Live)");
2062		kdb_printf(" 0x%p", mod->core_layout.base);
2063
2064#ifdef CONFIG_MODULE_UNLOAD
2065		{
2066			struct module_use *use;
2067			kdb_printf(" [ ");
2068			list_for_each_entry(use, &mod->source_list,
2069					    source_list)
2070				kdb_printf("%s ", use->target->name);
2071			kdb_printf("]\n");
2072		}
2073#endif
2074	}
2075
2076	return 0;
2077}
2078
2079#endif	/* CONFIG_MODULES */
2080
2081/*
2082 * kdb_env - This function implements the 'env' command.  Display the
2083 *	current environment variables.
2084 */
2085
2086static int kdb_env(int argc, const char **argv)
2087{
2088	int i;
2089
2090	for (i = 0; i < __nenv; i++) {
2091		if (__env[i])
2092			kdb_printf("%s\n", __env[i]);
2093	}
2094
2095	if (KDB_DEBUG(MASK))
2096		kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
2097
2098	return 0;
2099}
2100
2101#ifdef CONFIG_PRINTK
2102/*
2103 * kdb_dmesg - This function implements the 'dmesg' command to display
2104 *	the contents of the syslog buffer.
2105 *		dmesg [lines] [adjust]
2106 */
2107static int kdb_dmesg(int argc, const char **argv)
2108{
2109	int diag;
2110	int logging;
2111	int lines = 0;
2112	int adjust = 0;
2113	int n = 0;
2114	int skip = 0;
2115	struct kmsg_dumper dumper = { .active = 1 };
2116	size_t len;
2117	char buf[201];
2118
2119	if (argc > 2)
2120		return KDB_ARGCOUNT;
2121	if (argc) {
2122		char *cp;
2123		lines = simple_strtol(argv[1], &cp, 0);
2124		if (*cp)
2125			lines = 0;
2126		if (argc > 1) {
2127			adjust = simple_strtoul(argv[2], &cp, 0);
2128			if (*cp || adjust < 0)
2129				adjust = 0;
2130		}
2131	}
2132
2133	/* disable LOGGING if set */
2134	diag = kdbgetintenv("LOGGING", &logging);
2135	if (!diag && logging) {
2136		const char *setargs[] = { "set", "LOGGING", "0" };
2137		kdb_set(2, setargs);
2138	}
2139
2140	kmsg_dump_rewind_nolock(&dumper);
2141	while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
2142		n++;
2143
2144	if (lines < 0) {
2145		if (adjust >= n)
2146			kdb_printf("buffer only contains %d lines, nothing "
2147				   "printed\n", n);
2148		else if (adjust - lines >= n)
2149			kdb_printf("buffer only contains %d lines, last %d "
2150				   "lines printed\n", n, n - adjust);
2151		skip = adjust;
2152		lines = abs(lines);
2153	} else if (lines > 0) {
2154		skip = n - lines - adjust;
2155		lines = abs(lines);
2156		if (adjust >= n) {
2157			kdb_printf("buffer only contains %d lines, "
2158				   "nothing printed\n", n);
2159			skip = n;
2160		} else if (skip < 0) {
2161			lines += skip;
2162			skip = 0;
2163			kdb_printf("buffer only contains %d lines, first "
2164				   "%d lines printed\n", n, lines);
2165		}
2166	} else {
2167		lines = n;
2168	}
2169
2170	if (skip >= n || skip < 0)
2171		return 0;
2172
2173	kmsg_dump_rewind_nolock(&dumper);
2174	while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
2175		if (skip) {
2176			skip--;
2177			continue;
2178		}
2179		if (!lines--)
2180			break;
2181		if (KDB_FLAG(CMD_INTERRUPT))
2182			return 0;
2183
2184		kdb_printf("%.*s\n", (int)len - 1, buf);
2185	}
2186
2187	return 0;
2188}
2189#endif /* CONFIG_PRINTK */
2190
2191/* Make sure we balance enable/disable calls, must disable first. */
2192static atomic_t kdb_nmi_disabled;
2193
2194static int kdb_disable_nmi(int argc, const char *argv[])
2195{
2196	if (atomic_read(&kdb_nmi_disabled))
2197		return 0;
2198	atomic_set(&kdb_nmi_disabled, 1);
2199	arch_kgdb_ops.enable_nmi(0);
2200	return 0;
2201}
2202
2203static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2204{
2205	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2206		return -EINVAL;
2207	arch_kgdb_ops.enable_nmi(1);
2208	return 0;
2209}
2210
2211static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2212	.set = kdb_param_enable_nmi,
2213};
2214module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2215
2216/*
2217 * kdb_cpu - This function implements the 'cpu' command.
2218 *	cpu	[<cpunum>]
2219 * Returns:
2220 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2221 */
2222static void kdb_cpu_status(void)
2223{
2224	int i, start_cpu, first_print = 1;
2225	char state, prev_state = '?';
2226
2227	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2228	kdb_printf("Available cpus: ");
2229	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2230		if (!cpu_online(i)) {
2231			state = 'F';	/* cpu is offline */
2232		} else if (!kgdb_info[i].enter_kgdb) {
2233			state = 'D';	/* cpu is online but unresponsive */
2234		} else {
2235			state = ' ';	/* cpu is responding to kdb */
2236			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2237				state = 'I';	/* idle task */
2238		}
2239		if (state != prev_state) {
2240			if (prev_state != '?') {
2241				if (!first_print)
2242					kdb_printf(", ");
2243				first_print = 0;
2244				kdb_printf("%d", start_cpu);
2245				if (start_cpu < i-1)
2246					kdb_printf("-%d", i-1);
2247				if (prev_state != ' ')
2248					kdb_printf("(%c)", prev_state);
2249			}
2250			prev_state = state;
2251			start_cpu = i;
2252		}
2253	}
2254	/* print the trailing cpus, ignoring them if they are all offline */
2255	if (prev_state != 'F') {
2256		if (!first_print)
2257			kdb_printf(", ");
2258		kdb_printf("%d", start_cpu);
2259		if (start_cpu < i-1)
2260			kdb_printf("-%d", i-1);
2261		if (prev_state != ' ')
2262			kdb_printf("(%c)", prev_state);
2263	}
2264	kdb_printf("\n");
2265}
2266
2267static int kdb_cpu(int argc, const char **argv)
2268{
2269	unsigned long cpunum;
2270	int diag;
2271
2272	if (argc == 0) {
2273		kdb_cpu_status();
2274		return 0;
2275	}
2276
2277	if (argc != 1)
2278		return KDB_ARGCOUNT;
2279
2280	diag = kdbgetularg(argv[1], &cpunum);
2281	if (diag)
2282		return diag;
2283
2284	/*
2285	 * Validate cpunum
2286	 */
2287	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2288		return KDB_BADCPUNUM;
2289
2290	dbg_switch_cpu = cpunum;
2291
2292	/*
2293	 * Switch to other cpu
2294	 */
2295	return KDB_CMD_CPU;
2296}
2297
2298/* The user may not realize that ps/bta with no parameters does not print idle
2299 * or sleeping system daemon processes, so tell them how many were suppressed.
2300 */
2301void kdb_ps_suppressed(void)
2302{
2303	int idle = 0, daemon = 0;
2304	unsigned long mask_I = kdb_task_state_string("I"),
2305		      mask_M = kdb_task_state_string("M");
2306	unsigned long cpu;
2307	const struct task_struct *p, *g;
2308	for_each_online_cpu(cpu) {
2309		p = kdb_curr_task(cpu);
2310		if (kdb_task_state(p, mask_I))
2311			++idle;
2312	}
2313	kdb_do_each_thread(g, p) {
2314		if (kdb_task_state(p, mask_M))
2315			++daemon;
2316	} kdb_while_each_thread(g, p);
2317	if (idle || daemon) {
2318		if (idle)
2319			kdb_printf("%d idle process%s (state I)%s\n",
2320				   idle, idle == 1 ? "" : "es",
2321				   daemon ? " and " : "");
2322		if (daemon)
2323			kdb_printf("%d sleeping system daemon (state M) "
2324				   "process%s", daemon,
2325				   daemon == 1 ? "" : "es");
2326		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2327	}
2328}
2329
2330/*
2331 * kdb_ps - This function implements the 'ps' command which shows a
2332 *	list of the active processes.
2333 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2334 */
2335void kdb_ps1(const struct task_struct *p)
2336{
2337	int cpu;
2338	unsigned long tmp;
2339
2340	if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
2341		return;
2342
2343	cpu = kdb_process_cpu(p);
2344	kdb_printf("0x%p %8d %8d  %d %4d   %c  0x%p %c%s\n",
2345		   (void *)p, p->pid, p->parent->pid,
2346		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2347		   kdb_task_state_char(p),
2348		   (void *)(&p->thread),
2349		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2350		   p->comm);
2351	if (kdb_task_has_cpu(p)) {
2352		if (!KDB_TSK(cpu)) {
2353			kdb_printf("  Error: no saved data for this cpu\n");
2354		} else {
2355			if (KDB_TSK(cpu) != p)
2356				kdb_printf("  Error: does not match running "
2357				   "process table (0x%p)\n", KDB_TSK(cpu));
2358		}
2359	}
2360}
2361
2362static int kdb_ps(int argc, const char **argv)
2363{
2364	struct task_struct *g, *p;
2365	unsigned long mask, cpu;
2366
2367	if (argc == 0)
2368		kdb_ps_suppressed();
2369	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2370		(int)(2*sizeof(void *))+2, "Task Addr",
2371		(int)(2*sizeof(void *))+2, "Thread");
2372	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2373	/* Run the active tasks first */
2374	for_each_online_cpu(cpu) {
2375		if (KDB_FLAG(CMD_INTERRUPT))
2376			return 0;
2377		p = kdb_curr_task(cpu);
2378		if (kdb_task_state(p, mask))
2379			kdb_ps1(p);
2380	}
2381	kdb_printf("\n");
2382	/* Now the real tasks */
2383	kdb_do_each_thread(g, p) {
2384		if (KDB_FLAG(CMD_INTERRUPT))
2385			return 0;
2386		if (kdb_task_state(p, mask))
2387			kdb_ps1(p);
2388	} kdb_while_each_thread(g, p);
2389
2390	return 0;
2391}
2392
2393/*
2394 * kdb_pid - This function implements the 'pid' command which switches
2395 *	the currently active process.
2396 *		pid [<pid> | R]
2397 */
2398static int kdb_pid(int argc, const char **argv)
2399{
2400	struct task_struct *p;
2401	unsigned long val;
2402	int diag;
2403
2404	if (argc > 1)
2405		return KDB_ARGCOUNT;
2406
2407	if (argc) {
2408		if (strcmp(argv[1], "R") == 0) {
2409			p = KDB_TSK(kdb_initial_cpu);
2410		} else {
2411			diag = kdbgetularg(argv[1], &val);
2412			if (diag)
2413				return KDB_BADINT;
2414
2415			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2416			if (!p) {
2417				kdb_printf("No task with pid=%d\n", (pid_t)val);
2418				return 0;
2419			}
2420		}
2421		kdb_set_current_task(p);
2422	}
2423	kdb_printf("KDB current process is %s(pid=%d)\n",
2424		   kdb_current_task->comm,
2425		   kdb_current_task->pid);
2426
2427	return 0;
2428}
2429
2430static int kdb_kgdb(int argc, const char **argv)
2431{
2432	return KDB_CMD_KGDB;
2433}
2434
2435/*
2436 * kdb_help - This function implements the 'help' and '?' commands.
2437 */
2438static int kdb_help(int argc, const char **argv)
2439{
2440	kdbtab_t *kt;
2441	int i;
2442
2443	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2444	kdb_printf("-----------------------------"
2445		   "-----------------------------\n");
2446	for_each_kdbcmd(kt, i) {
2447		char *space = "";
2448		if (KDB_FLAG(CMD_INTERRUPT))
2449			return 0;
2450		if (!kt->cmd_name)
2451			continue;
2452		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2453			continue;
2454		if (strlen(kt->cmd_usage) > 20)
2455			space = "\n                                    ";
2456		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2457			   kt->cmd_usage, space, kt->cmd_help);
2458	}
2459	return 0;
2460}
2461
2462/*
2463 * kdb_kill - This function implements the 'kill' commands.
2464 */
2465static int kdb_kill(int argc, const char **argv)
2466{
2467	long sig, pid;
2468	char *endp;
2469	struct task_struct *p;
 
2470
2471	if (argc != 2)
2472		return KDB_ARGCOUNT;
2473
2474	sig = simple_strtol(argv[1], &endp, 0);
2475	if (*endp)
2476		return KDB_BADINT;
2477	if ((sig >= 0) || !valid_signal(-sig)) {
2478		kdb_printf("Invalid signal parameter.<-signal>\n");
2479		return 0;
2480	}
2481	sig = -sig;
2482
2483	pid = simple_strtol(argv[2], &endp, 0);
2484	if (*endp)
2485		return KDB_BADINT;
2486	if (pid <= 0) {
2487		kdb_printf("Process ID must be large than 0.\n");
2488		return 0;
2489	}
2490
2491	/* Find the process. */
2492	p = find_task_by_pid_ns(pid, &init_pid_ns);
2493	if (!p) {
2494		kdb_printf("The specified process isn't found.\n");
2495		return 0;
2496	}
2497	p = p->group_leader;
2498	kdb_send_sig(p, sig);
 
 
 
 
 
2499	return 0;
2500}
2501
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2502/*
2503 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2504 * I cannot call that code directly from kdb, it has an unconditional
2505 * cli()/sti() and calls routines that take locks which can stop the debugger.
2506 */
2507static void kdb_sysinfo(struct sysinfo *val)
2508{
2509	u64 uptime = ktime_get_mono_fast_ns();
2510
2511	memset(val, 0, sizeof(*val));
2512	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2513	val->loads[0] = avenrun[0];
2514	val->loads[1] = avenrun[1];
2515	val->loads[2] = avenrun[2];
2516	val->procs = nr_threads-1;
2517	si_meminfo(val);
2518
2519	return;
2520}
2521
2522/*
2523 * kdb_summary - This function implements the 'summary' command.
2524 */
2525static int kdb_summary(int argc, const char **argv)
2526{
2527	time64_t now;
2528	struct tm tm;
2529	struct sysinfo val;
2530
2531	if (argc)
2532		return KDB_ARGCOUNT;
2533
2534	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2535	kdb_printf("release    %s\n", init_uts_ns.name.release);
2536	kdb_printf("version    %s\n", init_uts_ns.name.version);
2537	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2538	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2539	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2540	kdb_printf("ccversion  %s\n", __stringify(CCVERSION));
2541
2542	now = __ktime_get_real_seconds();
2543	time64_to_tm(now, 0, &tm);
2544	kdb_printf("date       %04ld-%02d-%02d %02d:%02d:%02d "
2545		   "tz_minuteswest %d\n",
2546		1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2547		tm.tm_hour, tm.tm_min, tm.tm_sec,
2548		sys_tz.tz_minuteswest);
2549
2550	kdb_sysinfo(&val);
2551	kdb_printf("uptime     ");
2552	if (val.uptime > (24*60*60)) {
2553		int days = val.uptime / (24*60*60);
2554		val.uptime %= (24*60*60);
2555		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2556	}
2557	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2558
2559	/* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */
2560
2561#define LOAD_INT(x) ((x) >> FSHIFT)
2562#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
2563	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2564		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2565		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2566		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2567#undef LOAD_INT
2568#undef LOAD_FRAC
2569	/* Display in kilobytes */
2570#define K(x) ((x) << (PAGE_SHIFT - 10))
2571	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2572		   "Buffers:        %8lu kB\n",
2573		   K(val.totalram), K(val.freeram), K(val.bufferram));
2574	return 0;
2575}
2576
2577/*
2578 * kdb_per_cpu - This function implements the 'per_cpu' command.
2579 */
2580static int kdb_per_cpu(int argc, const char **argv)
2581{
2582	char fmtstr[64];
2583	int cpu, diag, nextarg = 1;
2584	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2585
2586	if (argc < 1 || argc > 3)
2587		return KDB_ARGCOUNT;
2588
2589	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2590	if (diag)
2591		return diag;
2592
2593	if (argc >= 2) {
2594		diag = kdbgetularg(argv[2], &bytesperword);
2595		if (diag)
2596			return diag;
2597	}
2598	if (!bytesperword)
2599		bytesperword = KDB_WORD_SIZE;
2600	else if (bytesperword > KDB_WORD_SIZE)
2601		return KDB_BADWIDTH;
2602	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2603	if (argc >= 3) {
2604		diag = kdbgetularg(argv[3], &whichcpu);
2605		if (diag)
2606			return diag;
2607		if (!cpu_online(whichcpu)) {
2608			kdb_printf("cpu %ld is not online\n", whichcpu);
2609			return KDB_BADCPUNUM;
2610		}
2611	}
2612
2613	/* Most architectures use __per_cpu_offset[cpu], some use
2614	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2615	 */
2616#ifdef	__per_cpu_offset
2617#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2618#else
2619#ifdef	CONFIG_SMP
2620#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2621#else
2622#define KDB_PCU(cpu) 0
2623#endif
2624#endif
2625	for_each_online_cpu(cpu) {
2626		if (KDB_FLAG(CMD_INTERRUPT))
2627			return 0;
2628
2629		if (whichcpu != ~0UL && whichcpu != cpu)
2630			continue;
2631		addr = symaddr + KDB_PCU(cpu);
2632		diag = kdb_getword(&val, addr, bytesperword);
2633		if (diag) {
2634			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2635				   "read, diag=%d\n", cpu, addr, diag);
2636			continue;
2637		}
2638		kdb_printf("%5d ", cpu);
2639		kdb_md_line(fmtstr, addr,
2640			bytesperword == KDB_WORD_SIZE,
2641			1, bytesperword, 1, 1, 0);
2642	}
2643#undef KDB_PCU
2644	return 0;
2645}
2646
2647/*
2648 * display help for the use of cmd | grep pattern
2649 */
2650static int kdb_grep_help(int argc, const char **argv)
2651{
2652	kdb_printf("Usage of  cmd args | grep pattern:\n");
2653	kdb_printf("  Any command's output may be filtered through an ");
2654	kdb_printf("emulated 'pipe'.\n");
2655	kdb_printf("  'grep' is just a key word.\n");
2656	kdb_printf("  The pattern may include a very limited set of "
2657		   "metacharacters:\n");
2658	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2659	kdb_printf("  And if there are spaces in the pattern, you may "
2660		   "quote it:\n");
2661	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2662		   " or \"^pat tern$\"\n");
2663	return 0;
2664}
2665
2666/*
2667 * kdb_register_flags - This function is used to register a kernel
2668 * 	debugger command.
2669 * Inputs:
2670 *	cmd	Command name
2671 *	func	Function to execute the command
2672 *	usage	A simple usage string showing arguments
2673 *	help	A simple help string describing command
2674 *	repeat	Does the command auto repeat on enter?
2675 * Returns:
2676 *	zero for success, one if a duplicate command.
2677 */
2678#define kdb_command_extend 50	/* arbitrary */
2679int kdb_register_flags(char *cmd,
2680		       kdb_func_t func,
2681		       char *usage,
2682		       char *help,
2683		       short minlen,
2684		       kdb_cmdflags_t flags)
2685{
2686	int i;
2687	kdbtab_t *kp;
2688
2689	/*
2690	 *  Brute force method to determine duplicates
2691	 */
2692	for_each_kdbcmd(kp, i) {
2693		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2694			kdb_printf("Duplicate kdb command registered: "
2695				"%s, func %p help %s\n", cmd, func, help);
2696			return 1;
2697		}
2698	}
2699
2700	/*
2701	 * Insert command into first available location in table
2702	 */
2703	for_each_kdbcmd(kp, i) {
2704		if (kp->cmd_name == NULL)
2705			break;
2706	}
2707
2708	if (i >= kdb_max_commands) {
2709		kdbtab_t *new = kmalloc((kdb_max_commands - KDB_BASE_CMD_MAX +
2710			 kdb_command_extend) * sizeof(*new), GFP_KDB);
2711		if (!new) {
2712			kdb_printf("Could not allocate new kdb_command "
2713				   "table\n");
2714			return 1;
2715		}
2716		if (kdb_commands) {
2717			memcpy(new, kdb_commands,
2718			  (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new));
2719			kfree(kdb_commands);
2720		}
2721		memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0,
2722		       kdb_command_extend * sizeof(*new));
2723		kdb_commands = new;
2724		kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX;
2725		kdb_max_commands += kdb_command_extend;
2726	}
2727
2728	kp->cmd_name   = cmd;
2729	kp->cmd_func   = func;
2730	kp->cmd_usage  = usage;
2731	kp->cmd_help   = help;
2732	kp->cmd_minlen = minlen;
2733	kp->cmd_flags  = flags;
2734
2735	return 0;
2736}
2737EXPORT_SYMBOL_GPL(kdb_register_flags);
2738
2739
2740/*
2741 * kdb_register - Compatibility register function for commands that do
2742 *	not need to specify a repeat state.  Equivalent to
2743 *	kdb_register_flags with flags set to 0.
2744 * Inputs:
2745 *	cmd	Command name
2746 *	func	Function to execute the command
2747 *	usage	A simple usage string showing arguments
2748 *	help	A simple help string describing command
2749 * Returns:
2750 *	zero for success, one if a duplicate command.
2751 */
2752int kdb_register(char *cmd,
2753	     kdb_func_t func,
2754	     char *usage,
2755	     char *help,
2756	     short minlen)
2757{
2758	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2759}
2760EXPORT_SYMBOL_GPL(kdb_register);
2761
2762/*
2763 * kdb_unregister - This function is used to unregister a kernel
2764 *	debugger command.  It is generally called when a module which
2765 *	implements kdb commands is unloaded.
2766 * Inputs:
2767 *	cmd	Command name
2768 * Returns:
2769 *	zero for success, one command not registered.
2770 */
2771int kdb_unregister(char *cmd)
2772{
2773	int i;
2774	kdbtab_t *kp;
2775
2776	/*
2777	 *  find the command.
2778	 */
2779	for_each_kdbcmd(kp, i) {
2780		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2781			kp->cmd_name = NULL;
2782			return 0;
2783		}
2784	}
2785
2786	/* Couldn't find it.  */
2787	return 1;
2788}
2789EXPORT_SYMBOL_GPL(kdb_unregister);
2790
2791/* Initialize the kdb command table. */
2792static void __init kdb_inittab(void)
2793{
2794	int i;
2795	kdbtab_t *kp;
2796
2797	for_each_kdbcmd(kp, i)
2798		kp->cmd_name = NULL;
2799
2800	kdb_register_flags("md", kdb_md, "<vaddr>",
2801	  "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2802	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2803	kdb_register_flags("mdr", kdb_md, "<vaddr> <bytes>",
2804	  "Display Raw Memory", 0,
2805	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2806	kdb_register_flags("mdp", kdb_md, "<paddr> <bytes>",
2807	  "Display Physical Memory", 0,
2808	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2809	kdb_register_flags("mds", kdb_md, "<vaddr>",
2810	  "Display Memory Symbolically", 0,
2811	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2812	kdb_register_flags("mm", kdb_mm, "<vaddr> <contents>",
2813	  "Modify Memory Contents", 0,
2814	  KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS);
2815	kdb_register_flags("go", kdb_go, "[<vaddr>]",
2816	  "Continue Execution", 1,
2817	  KDB_ENABLE_REG_WRITE | KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2818	kdb_register_flags("rd", kdb_rd, "",
2819	  "Display Registers", 0,
2820	  KDB_ENABLE_REG_READ);
2821	kdb_register_flags("rm", kdb_rm, "<reg> <contents>",
2822	  "Modify Registers", 0,
2823	  KDB_ENABLE_REG_WRITE);
2824	kdb_register_flags("ef", kdb_ef, "<vaddr>",
2825	  "Display exception frame", 0,
2826	  KDB_ENABLE_MEM_READ);
2827	kdb_register_flags("bt", kdb_bt, "[<vaddr>]",
2828	  "Stack traceback", 1,
2829	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2830	kdb_register_flags("btp", kdb_bt, "<pid>",
2831	  "Display stack for process <pid>", 0,
2832	  KDB_ENABLE_INSPECT);
2833	kdb_register_flags("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
2834	  "Backtrace all processes matching state flag", 0,
2835	  KDB_ENABLE_INSPECT);
2836	kdb_register_flags("btc", kdb_bt, "",
2837	  "Backtrace current process on each cpu", 0,
2838	  KDB_ENABLE_INSPECT);
2839	kdb_register_flags("btt", kdb_bt, "<vaddr>",
2840	  "Backtrace process given its struct task address", 0,
2841	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2842	kdb_register_flags("env", kdb_env, "",
2843	  "Show environment variables", 0,
2844	  KDB_ENABLE_ALWAYS_SAFE);
2845	kdb_register_flags("set", kdb_set, "",
2846	  "Set environment variables", 0,
2847	  KDB_ENABLE_ALWAYS_SAFE);
2848	kdb_register_flags("help", kdb_help, "",
2849	  "Display Help Message", 1,
2850	  KDB_ENABLE_ALWAYS_SAFE);
2851	kdb_register_flags("?", kdb_help, "",
2852	  "Display Help Message", 0,
2853	  KDB_ENABLE_ALWAYS_SAFE);
2854	kdb_register_flags("cpu", kdb_cpu, "<cpunum>",
2855	  "Switch to new cpu", 0,
2856	  KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2857	kdb_register_flags("kgdb", kdb_kgdb, "",
2858	  "Enter kgdb mode", 0, 0);
2859	kdb_register_flags("ps", kdb_ps, "[<flags>|A]",
2860	  "Display active task list", 0,
2861	  KDB_ENABLE_INSPECT);
2862	kdb_register_flags("pid", kdb_pid, "<pidnum>",
2863	  "Switch to another task", 0,
2864	  KDB_ENABLE_INSPECT);
2865	kdb_register_flags("reboot", kdb_reboot, "",
2866	  "Reboot the machine immediately", 0,
2867	  KDB_ENABLE_REBOOT);
2868#if defined(CONFIG_MODULES)
2869	kdb_register_flags("lsmod", kdb_lsmod, "",
2870	  "List loaded kernel modules", 0,
2871	  KDB_ENABLE_INSPECT);
2872#endif
2873#if defined(CONFIG_MAGIC_SYSRQ)
2874	kdb_register_flags("sr", kdb_sr, "<key>",
2875	  "Magic SysRq key", 0,
2876	  KDB_ENABLE_ALWAYS_SAFE);
2877#endif
2878#if defined(CONFIG_PRINTK)
2879	kdb_register_flags("dmesg", kdb_dmesg, "[lines]",
2880	  "Display syslog buffer", 0,
2881	  KDB_ENABLE_ALWAYS_SAFE);
2882#endif
2883	if (arch_kgdb_ops.enable_nmi) {
2884		kdb_register_flags("disable_nmi", kdb_disable_nmi, "",
2885		  "Disable NMI entry to KDB", 0,
2886		  KDB_ENABLE_ALWAYS_SAFE);
2887	}
2888	kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2889	  "Define a set of commands, down to endefcmd", 0,
2890	  KDB_ENABLE_ALWAYS_SAFE);
2891	kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
2892	  "Send a signal to a process", 0,
2893	  KDB_ENABLE_SIGNAL);
2894	kdb_register_flags("summary", kdb_summary, "",
2895	  "Summarize the system", 4,
2896	  KDB_ENABLE_ALWAYS_SAFE);
2897	kdb_register_flags("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]",
2898	  "Display per_cpu variables", 3,
2899	  KDB_ENABLE_MEM_READ);
2900	kdb_register_flags("grephelp", kdb_grep_help, "",
2901	  "Display help on | grep", 0,
2902	  KDB_ENABLE_ALWAYS_SAFE);
2903}
2904
2905/* Execute any commands defined in kdb_cmds.  */
2906static void __init kdb_cmd_init(void)
2907{
2908	int i, diag;
2909	for (i = 0; kdb_cmds[i]; ++i) {
2910		diag = kdb_parse(kdb_cmds[i]);
2911		if (diag)
2912			kdb_printf("kdb command %s failed, kdb diag %d\n",
2913				kdb_cmds[i], diag);
2914	}
2915	if (defcmd_in_progress) {
2916		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2917		kdb_parse("endefcmd");
2918	}
2919}
2920
2921/* Initialize kdb_printf, breakpoint tables and kdb state */
2922void __init kdb_init(int lvl)
2923{
2924	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2925	int i;
2926
2927	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2928		return;
2929	for (i = kdb_init_lvl; i < lvl; i++) {
2930		switch (i) {
2931		case KDB_NOT_INITIALIZED:
2932			kdb_inittab();		/* Initialize Command Table */
2933			kdb_initbptab();	/* Initialize Breakpoints */
2934			break;
2935		case KDB_INIT_EARLY:
2936			kdb_cmd_init();		/* Build kdb_cmds tables */
2937			break;
2938		}
2939	}
2940	kdb_init_lvl = lvl;
2941}
v4.6
   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/sysrq.h>
  22#include <linux/smp.h>
  23#include <linux/utsname.h>
  24#include <linux/vmalloc.h>
  25#include <linux/atomic.h>
  26#include <linux/module.h>
  27#include <linux/moduleparam.h>
  28#include <linux/mm.h>
  29#include <linux/init.h>
  30#include <linux/kallsyms.h>
  31#include <linux/kgdb.h>
  32#include <linux/kdb.h>
  33#include <linux/notifier.h>
  34#include <linux/interrupt.h>
  35#include <linux/delay.h>
  36#include <linux/nmi.h>
  37#include <linux/time.h>
  38#include <linux/ptrace.h>
  39#include <linux/sysctl.h>
  40#include <linux/cpu.h>
  41#include <linux/kdebug.h>
  42#include <linux/proc_fs.h>
  43#include <linux/uaccess.h>
  44#include <linux/slab.h>
  45#include "kdb_private.h"
  46
  47#undef	MODULE_PARAM_PREFIX
  48#define	MODULE_PARAM_PREFIX "kdb."
  49
  50static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  51module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  52
  53char kdb_grep_string[KDB_GREP_STRLEN];
  54int kdb_grepping_flag;
  55EXPORT_SYMBOL(kdb_grepping_flag);
  56int kdb_grep_leading;
  57int kdb_grep_trailing;
  58
  59/*
  60 * Kernel debugger state flags
  61 */
  62int kdb_flags;
  63atomic_t kdb_event;
  64
  65/*
  66 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  67 * single thread processors through the kernel debugger.
  68 */
  69int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  70int kdb_nextline = 1;
  71int kdb_state;			/* General KDB state */
  72
  73struct task_struct *kdb_current_task;
  74EXPORT_SYMBOL(kdb_current_task);
  75struct pt_regs *kdb_current_regs;
  76
  77const char *kdb_diemsg;
  78static int kdb_go_count;
  79#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
  80static unsigned int kdb_continue_catastrophic =
  81	CONFIG_KDB_CONTINUE_CATASTROPHIC;
  82#else
  83static unsigned int kdb_continue_catastrophic;
  84#endif
  85
  86/* kdb_commands describes the available commands. */
  87static kdbtab_t *kdb_commands;
  88#define KDB_BASE_CMD_MAX 50
  89static int kdb_max_commands = KDB_BASE_CMD_MAX;
  90static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX];
  91#define for_each_kdbcmd(cmd, num)					\
  92	for ((cmd) = kdb_base_commands, (num) = 0;			\
  93	     num < kdb_max_commands;					\
  94	     num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++)
  95
  96typedef struct _kdbmsg {
  97	int	km_diag;	/* kdb diagnostic */
  98	char	*km_msg;	/* Corresponding message text */
  99} kdbmsg_t;
 100
 101#define KDBMSG(msgnum, text) \
 102	{ KDB_##msgnum, text }
 103
 104static kdbmsg_t kdbmsgs[] = {
 105	KDBMSG(NOTFOUND, "Command Not Found"),
 106	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 107	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 108	       "8 is only allowed on 64 bit systems"),
 109	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 110	KDBMSG(NOTENV, "Cannot find environment variable"),
 111	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 112	KDBMSG(NOTIMP, "Command not implemented"),
 113	KDBMSG(ENVFULL, "Environment full"),
 114	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 115	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 116#ifdef CONFIG_CPU_XSCALE
 117	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 118#else
 119	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 120#endif
 121	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 122	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 123	KDBMSG(BADMODE, "Invalid IDMODE"),
 124	KDBMSG(BADINT, "Illegal numeric value"),
 125	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 126	KDBMSG(BADREG, "Invalid register name"),
 127	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 128	KDBMSG(BADLENGTH, "Invalid length field"),
 129	KDBMSG(NOBP, "No Breakpoint exists"),
 130	KDBMSG(BADADDR, "Invalid address"),
 131	KDBMSG(NOPERM, "Permission denied"),
 132};
 133#undef KDBMSG
 134
 135static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 136
 137
 138/*
 139 * Initial environment.   This is all kept static and local to
 140 * this file.   We don't want to rely on the memory allocation
 141 * mechanisms in the kernel, so we use a very limited allocate-only
 142 * heap for new and altered environment variables.  The entire
 143 * environment is limited to a fixed number of entries (add more
 144 * to __env[] if required) and a fixed amount of heap (add more to
 145 * KDB_ENVBUFSIZE if required).
 146 */
 147
 148static char *__env[] = {
 149#if defined(CONFIG_SMP)
 150 "PROMPT=[%d]kdb> ",
 151#else
 152 "PROMPT=kdb> ",
 153#endif
 154 "MOREPROMPT=more> ",
 155 "RADIX=16",
 156 "MDCOUNT=8",			/* lines of md output */
 157 KDB_PLATFORM_ENV,
 158 "DTABCOUNT=30",
 159 "NOSECT=1",
 160 (char *)0,
 161 (char *)0,
 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};
 185
 186static const int __nenv = ARRAY_SIZE(__env);
 187
 188struct task_struct *kdb_curr_task(int cpu)
 189{
 190	struct task_struct *p = curr_task(cpu);
 191#ifdef	_TIF_MCA_INIT
 192	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 193		p = krp->p;
 194#endif
 195	return p;
 196}
 197
 198/*
 199 * Check whether the flags of the current command and the permissions
 200 * of the kdb console has allow a command to be run.
 201 */
 202static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 203				   bool no_args)
 204{
 205	/* permissions comes from userspace so needs massaging slightly */
 206	permissions &= KDB_ENABLE_MASK;
 207	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 208
 209	/* some commands change group when launched with no arguments */
 210	if (no_args)
 211		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 212
 213	flags |= KDB_ENABLE_ALL;
 214
 215	return permissions & flags;
 216}
 217
 218/*
 219 * kdbgetenv - This function will return the character string value of
 220 *	an environment variable.
 221 * Parameters:
 222 *	match	A character string representing an environment variable.
 223 * Returns:
 224 *	NULL	No environment variable matches 'match'
 225 *	char*	Pointer to string value of environment variable.
 226 */
 227char *kdbgetenv(const char *match)
 228{
 229	char **ep = __env;
 230	int matchlen = strlen(match);
 231	int i;
 232
 233	for (i = 0; i < __nenv; i++) {
 234		char *e = *ep++;
 235
 236		if (!e)
 237			continue;
 238
 239		if ((strncmp(match, e, matchlen) == 0)
 240		 && ((e[matchlen] == '\0')
 241		   || (e[matchlen] == '='))) {
 242			char *cp = strchr(e, '=');
 243			return cp ? ++cp : "";
 244		}
 245	}
 246	return NULL;
 247}
 248
 249/*
 250 * kdballocenv - This function is used to allocate bytes for
 251 *	environment entries.
 252 * Parameters:
 253 *	match	A character string representing a numeric value
 254 * Outputs:
 255 *	*value  the unsigned long representation of the env variable 'match'
 256 * Returns:
 257 *	Zero on success, a kdb diagnostic on failure.
 258 * Remarks:
 259 *	We use a static environment buffer (envbuffer) to hold the values
 260 *	of dynamically generated environment variables (see kdb_set).  Buffer
 261 *	space once allocated is never free'd, so over time, the amount of space
 262 *	(currently 512 bytes) will be exhausted if env variables are changed
 263 *	frequently.
 264 */
 265static char *kdballocenv(size_t bytes)
 266{
 267#define	KDB_ENVBUFSIZE	512
 268	static char envbuffer[KDB_ENVBUFSIZE];
 269	static int envbufsize;
 270	char *ep = NULL;
 271
 272	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 273		ep = &envbuffer[envbufsize];
 274		envbufsize += bytes;
 275	}
 276	return ep;
 277}
 278
 279/*
 280 * kdbgetulenv - This function will return the value of an unsigned
 281 *	long-valued environment variable.
 282 * Parameters:
 283 *	match	A character string representing a numeric value
 284 * Outputs:
 285 *	*value  the unsigned long represntation of the env variable 'match'
 286 * Returns:
 287 *	Zero on success, a kdb diagnostic on failure.
 288 */
 289static int kdbgetulenv(const char *match, unsigned long *value)
 290{
 291	char *ep;
 292
 293	ep = kdbgetenv(match);
 294	if (!ep)
 295		return KDB_NOTENV;
 296	if (strlen(ep) == 0)
 297		return KDB_NOENVVALUE;
 298
 299	*value = simple_strtoul(ep, NULL, 0);
 300
 301	return 0;
 302}
 303
 304/*
 305 * kdbgetintenv - This function will return the value of an
 306 *	integer-valued environment variable.
 307 * Parameters:
 308 *	match	A character string representing an integer-valued env variable
 309 * Outputs:
 310 *	*value  the integer representation of the environment variable 'match'
 311 * Returns:
 312 *	Zero on success, a kdb diagnostic on failure.
 313 */
 314int kdbgetintenv(const char *match, int *value)
 315{
 316	unsigned long val;
 317	int diag;
 318
 319	diag = kdbgetulenv(match, &val);
 320	if (!diag)
 321		*value = (int) val;
 322	return diag;
 323}
 324
 325/*
 326 * kdbgetularg - This function will convert a numeric string into an
 327 *	unsigned long value.
 328 * Parameters:
 329 *	arg	A character string representing a numeric value
 330 * Outputs:
 331 *	*value  the unsigned long represntation of arg.
 332 * Returns:
 333 *	Zero on success, a kdb diagnostic on failure.
 334 */
 335int kdbgetularg(const char *arg, unsigned long *value)
 336{
 337	char *endp;
 338	unsigned long val;
 339
 340	val = simple_strtoul(arg, &endp, 0);
 341
 342	if (endp == arg) {
 343		/*
 344		 * Also try base 16, for us folks too lazy to type the
 345		 * leading 0x...
 346		 */
 347		val = simple_strtoul(arg, &endp, 16);
 348		if (endp == arg)
 349			return KDB_BADINT;
 350	}
 351
 352	*value = val;
 353
 354	return 0;
 355}
 356
 357int kdbgetu64arg(const char *arg, u64 *value)
 358{
 359	char *endp;
 360	u64 val;
 361
 362	val = simple_strtoull(arg, &endp, 0);
 363
 364	if (endp == arg) {
 365
 366		val = simple_strtoull(arg, &endp, 16);
 367		if (endp == arg)
 368			return KDB_BADINT;
 369	}
 370
 371	*value = val;
 372
 373	return 0;
 374}
 375
 376/*
 377 * kdb_set - This function implements the 'set' command.  Alter an
 378 *	existing environment variable or create a new one.
 379 */
 380int kdb_set(int argc, const char **argv)
 381{
 382	int i;
 383	char *ep;
 384	size_t varlen, vallen;
 385
 386	/*
 387	 * we can be invoked two ways:
 388	 *   set var=value    argv[1]="var", argv[2]="value"
 389	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 390	 * - if the latter, shift 'em down.
 391	 */
 392	if (argc == 3) {
 393		argv[2] = argv[3];
 394		argc--;
 395	}
 396
 397	if (argc != 2)
 398		return KDB_ARGCOUNT;
 399
 400	/*
 401	 * Check for internal variables
 402	 */
 403	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 404		unsigned int debugflags;
 405		char *cp;
 406
 407		debugflags = simple_strtoul(argv[2], &cp, 0);
 408		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 409			kdb_printf("kdb: illegal debug flags '%s'\n",
 410				    argv[2]);
 411			return 0;
 412		}
 413		kdb_flags = (kdb_flags &
 414			     ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
 415			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 416
 417		return 0;
 418	}
 419
 420	/*
 421	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 422	 * name, argv[2] = value.
 423	 */
 424	varlen = strlen(argv[1]);
 425	vallen = strlen(argv[2]);
 426	ep = kdballocenv(varlen + vallen + 2);
 427	if (ep == (char *)0)
 428		return KDB_ENVBUFFULL;
 429
 430	sprintf(ep, "%s=%s", argv[1], argv[2]);
 431
 432	ep[varlen+vallen+1] = '\0';
 433
 434	for (i = 0; i < __nenv; i++) {
 435		if (__env[i]
 436		 && ((strncmp(__env[i], argv[1], varlen) == 0)
 437		   && ((__env[i][varlen] == '\0')
 438		    || (__env[i][varlen] == '=')))) {
 439			__env[i] = ep;
 440			return 0;
 441		}
 442	}
 443
 444	/*
 445	 * Wasn't existing variable.  Fit into slot.
 446	 */
 447	for (i = 0; i < __nenv-1; i++) {
 448		if (__env[i] == (char *)0) {
 449			__env[i] = ep;
 450			return 0;
 451		}
 452	}
 453
 454	return KDB_ENVFULL;
 455}
 456
 457static int kdb_check_regs(void)
 458{
 459	if (!kdb_current_regs) {
 460		kdb_printf("No current kdb registers."
 461			   "  You may need to select another task\n");
 462		return KDB_BADREG;
 463	}
 464	return 0;
 465}
 466
 467/*
 468 * kdbgetaddrarg - This function is responsible for parsing an
 469 *	address-expression and returning the value of the expression,
 470 *	symbol name, and offset to the caller.
 471 *
 472 *	The argument may consist of a numeric value (decimal or
 473 *	hexidecimal), a symbol name, a register name (preceded by the
 474 *	percent sign), an environment variable with a numeric value
 475 *	(preceded by a dollar sign) or a simple arithmetic expression
 476 *	consisting of a symbol name, +/-, and a numeric constant value
 477 *	(offset).
 478 * Parameters:
 479 *	argc	- count of arguments in argv
 480 *	argv	- argument vector
 481 *	*nextarg - index to next unparsed argument in argv[]
 482 *	regs	- Register state at time of KDB entry
 483 * Outputs:
 484 *	*value	- receives the value of the address-expression
 485 *	*offset - receives the offset specified, if any
 486 *	*name   - receives the symbol name, if any
 487 *	*nextarg - index to next unparsed argument in argv[]
 488 * Returns:
 489 *	zero is returned on success, a kdb diagnostic code is
 490 *      returned on error.
 491 */
 492int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 493		  unsigned long *value,  long *offset,
 494		  char **name)
 495{
 496	unsigned long addr;
 497	unsigned long off = 0;
 498	int positive;
 499	int diag;
 500	int found = 0;
 501	char *symname;
 502	char symbol = '\0';
 503	char *cp;
 504	kdb_symtab_t symtab;
 505
 506	/*
 507	 * If the enable flags prohibit both arbitrary memory access
 508	 * and flow control then there are no reasonable grounds to
 509	 * provide symbol lookup.
 510	 */
 511	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 512			     kdb_cmd_enabled, false))
 513		return KDB_NOPERM;
 514
 515	/*
 516	 * Process arguments which follow the following syntax:
 517	 *
 518	 *  symbol | numeric-address [+/- numeric-offset]
 519	 *  %register
 520	 *  $environment-variable
 521	 */
 522
 523	if (*nextarg > argc)
 524		return KDB_ARGCOUNT;
 525
 526	symname = (char *)argv[*nextarg];
 527
 528	/*
 529	 * If there is no whitespace between the symbol
 530	 * or address and the '+' or '-' symbols, we
 531	 * remember the character and replace it with a
 532	 * null so the symbol/value can be properly parsed
 533	 */
 534	cp = strpbrk(symname, "+-");
 535	if (cp != NULL) {
 536		symbol = *cp;
 537		*cp++ = '\0';
 538	}
 539
 540	if (symname[0] == '$') {
 541		diag = kdbgetulenv(&symname[1], &addr);
 542		if (diag)
 543			return diag;
 544	} else if (symname[0] == '%') {
 545		diag = kdb_check_regs();
 546		if (diag)
 547			return diag;
 548		/* Implement register values with % at a later time as it is
 549		 * arch optional.
 550		 */
 551		return KDB_NOTIMP;
 552	} else {
 553		found = kdbgetsymval(symname, &symtab);
 554		if (found) {
 555			addr = symtab.sym_start;
 556		} else {
 557			diag = kdbgetularg(argv[*nextarg], &addr);
 558			if (diag)
 559				return diag;
 560		}
 561	}
 562
 563	if (!found)
 564		found = kdbnearsym(addr, &symtab);
 565
 566	(*nextarg)++;
 567
 568	if (name)
 569		*name = symname;
 570	if (value)
 571		*value = addr;
 572	if (offset && name && *name)
 573		*offset = addr - symtab.sym_start;
 574
 575	if ((*nextarg > argc)
 576	 && (symbol == '\0'))
 577		return 0;
 578
 579	/*
 580	 * check for +/- and offset
 581	 */
 582
 583	if (symbol == '\0') {
 584		if ((argv[*nextarg][0] != '+')
 585		 && (argv[*nextarg][0] != '-')) {
 586			/*
 587			 * Not our argument.  Return.
 588			 */
 589			return 0;
 590		} else {
 591			positive = (argv[*nextarg][0] == '+');
 592			(*nextarg)++;
 593		}
 594	} else
 595		positive = (symbol == '+');
 596
 597	/*
 598	 * Now there must be an offset!
 599	 */
 600	if ((*nextarg > argc)
 601	 && (symbol == '\0')) {
 602		return KDB_INVADDRFMT;
 603	}
 604
 605	if (!symbol) {
 606		cp = (char *)argv[*nextarg];
 607		(*nextarg)++;
 608	}
 609
 610	diag = kdbgetularg(cp, &off);
 611	if (diag)
 612		return diag;
 613
 614	if (!positive)
 615		off = -off;
 616
 617	if (offset)
 618		*offset += off;
 619
 620	if (value)
 621		*value += off;
 622
 623	return 0;
 624}
 625
 626static void kdb_cmderror(int diag)
 627{
 628	int i;
 629
 630	if (diag >= 0) {
 631		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 632		return;
 633	}
 634
 635	for (i = 0; i < __nkdb_err; i++) {
 636		if (kdbmsgs[i].km_diag == diag) {
 637			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 638			return;
 639		}
 640	}
 641
 642	kdb_printf("Unknown diag %d\n", -diag);
 643}
 644
 645/*
 646 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 647 *	command which defines one command as a set of other commands,
 648 *	terminated by endefcmd.  kdb_defcmd processes the initial
 649 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 650 *	the following commands until 'endefcmd'.
 651 * Inputs:
 652 *	argc	argument count
 653 *	argv	argument vector
 654 * Returns:
 655 *	zero for success, a kdb diagnostic if error
 656 */
 657struct defcmd_set {
 658	int count;
 659	int usable;
 660	char *name;
 661	char *usage;
 662	char *help;
 663	char **command;
 664};
 665static struct defcmd_set *defcmd_set;
 666static int defcmd_set_count;
 667static int defcmd_in_progress;
 668
 669/* Forward references */
 670static int kdb_exec_defcmd(int argc, const char **argv);
 671
 672static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 673{
 674	struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
 675	char **save_command = s->command;
 676	if (strcmp(argv0, "endefcmd") == 0) {
 677		defcmd_in_progress = 0;
 678		if (!s->count)
 679			s->usable = 0;
 680		if (s->usable)
 681			/* macros are always safe because when executed each
 682			 * internal command re-enters kdb_parse() and is
 683			 * safety checked individually.
 684			 */
 685			kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
 686					   s->help, 0,
 687					   KDB_ENABLE_ALWAYS_SAFE);
 688		return 0;
 689	}
 690	if (!s->usable)
 691		return KDB_NOTIMP;
 692	s->command = kzalloc((s->count + 1) * sizeof(*(s->command)), GFP_KDB);
 693	if (!s->command) {
 694		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
 695			   cmdstr);
 696		s->usable = 0;
 697		return KDB_NOTIMP;
 698	}
 699	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
 700	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
 701	kfree(save_command);
 702	return 0;
 703}
 704
 705static int kdb_defcmd(int argc, const char **argv)
 706{
 707	struct defcmd_set *save_defcmd_set = defcmd_set, *s;
 708	if (defcmd_in_progress) {
 709		kdb_printf("kdb: nested defcmd detected, assuming missing "
 710			   "endefcmd\n");
 711		kdb_defcmd2("endefcmd", "endefcmd");
 712	}
 713	if (argc == 0) {
 714		int i;
 715		for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
 716			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
 717				   s->usage, s->help);
 718			for (i = 0; i < s->count; ++i)
 719				kdb_printf("%s", s->command[i]);
 720			kdb_printf("endefcmd\n");
 721		}
 722		return 0;
 723	}
 724	if (argc != 3)
 725		return KDB_ARGCOUNT;
 726	if (in_dbg_master()) {
 727		kdb_printf("Command only available during kdb_init()\n");
 728		return KDB_NOTIMP;
 729	}
 730	defcmd_set = kmalloc((defcmd_set_count + 1) * sizeof(*defcmd_set),
 731			     GFP_KDB);
 732	if (!defcmd_set)
 733		goto fail_defcmd;
 734	memcpy(defcmd_set, save_defcmd_set,
 735	       defcmd_set_count * sizeof(*defcmd_set));
 736	s = defcmd_set + defcmd_set_count;
 737	memset(s, 0, sizeof(*s));
 738	s->usable = 1;
 739	s->name = kdb_strdup(argv[1], GFP_KDB);
 740	if (!s->name)
 741		goto fail_name;
 742	s->usage = kdb_strdup(argv[2], GFP_KDB);
 743	if (!s->usage)
 744		goto fail_usage;
 745	s->help = kdb_strdup(argv[3], GFP_KDB);
 746	if (!s->help)
 747		goto fail_help;
 748	if (s->usage[0] == '"') {
 749		strcpy(s->usage, argv[2]+1);
 750		s->usage[strlen(s->usage)-1] = '\0';
 751	}
 752	if (s->help[0] == '"') {
 753		strcpy(s->help, argv[3]+1);
 754		s->help[strlen(s->help)-1] = '\0';
 755	}
 756	++defcmd_set_count;
 757	defcmd_in_progress = 1;
 758	kfree(save_defcmd_set);
 759	return 0;
 760fail_help:
 761	kfree(s->usage);
 762fail_usage:
 763	kfree(s->name);
 764fail_name:
 765	kfree(defcmd_set);
 766fail_defcmd:
 767	kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
 768	defcmd_set = save_defcmd_set;
 769	return KDB_NOTIMP;
 770}
 771
 772/*
 773 * kdb_exec_defcmd - Execute the set of commands associated with this
 774 *	defcmd name.
 775 * Inputs:
 776 *	argc	argument count
 777 *	argv	argument vector
 778 * Returns:
 779 *	zero for success, a kdb diagnostic if error
 780 */
 781static int kdb_exec_defcmd(int argc, const char **argv)
 782{
 783	int i, ret;
 784	struct defcmd_set *s;
 785	if (argc != 0)
 786		return KDB_ARGCOUNT;
 787	for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
 788		if (strcmp(s->name, argv[0]) == 0)
 789			break;
 790	}
 791	if (i == defcmd_set_count) {
 792		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 793			   argv[0]);
 794		return KDB_NOTIMP;
 795	}
 796	for (i = 0; i < s->count; ++i) {
 797		/* Recursive use of kdb_parse, do not use argv after
 798		 * this point */
 799		argv = NULL;
 800		kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
 801		ret = kdb_parse(s->command[i]);
 802		if (ret)
 803			return ret;
 804	}
 805	return 0;
 806}
 807
 808/* Command history */
 809#define KDB_CMD_HISTORY_COUNT	32
 810#define CMD_BUFLEN		200	/* kdb_printf: max printline
 811					 * size == 256 */
 812static unsigned int cmd_head, cmd_tail;
 813static unsigned int cmdptr;
 814static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 815static char cmd_cur[CMD_BUFLEN];
 816
 817/*
 818 * The "str" argument may point to something like  | grep xyz
 819 */
 820static void parse_grep(const char *str)
 821{
 822	int	len;
 823	char	*cp = (char *)str, *cp2;
 824
 825	/* sanity check: we should have been called with the \ first */
 826	if (*cp != '|')
 827		return;
 828	cp++;
 829	while (isspace(*cp))
 830		cp++;
 831	if (strncmp(cp, "grep ", 5)) {
 832		kdb_printf("invalid 'pipe', see grephelp\n");
 833		return;
 834	}
 835	cp += 5;
 836	while (isspace(*cp))
 837		cp++;
 838	cp2 = strchr(cp, '\n');
 839	if (cp2)
 840		*cp2 = '\0'; /* remove the trailing newline */
 841	len = strlen(cp);
 842	if (len == 0) {
 843		kdb_printf("invalid 'pipe', see grephelp\n");
 844		return;
 845	}
 846	/* now cp points to a nonzero length search string */
 847	if (*cp == '"') {
 848		/* allow it be "x y z" by removing the "'s - there must
 849		   be two of them */
 850		cp++;
 851		cp2 = strchr(cp, '"');
 852		if (!cp2) {
 853			kdb_printf("invalid quoted string, see grephelp\n");
 854			return;
 855		}
 856		*cp2 = '\0'; /* end the string where the 2nd " was */
 857	}
 858	kdb_grep_leading = 0;
 859	if (*cp == '^') {
 860		kdb_grep_leading = 1;
 861		cp++;
 862	}
 863	len = strlen(cp);
 864	kdb_grep_trailing = 0;
 865	if (*(cp+len-1) == '$') {
 866		kdb_grep_trailing = 1;
 867		*(cp+len-1) = '\0';
 868	}
 869	len = strlen(cp);
 870	if (!len)
 871		return;
 872	if (len >= KDB_GREP_STRLEN) {
 873		kdb_printf("search string too long\n");
 874		return;
 875	}
 876	strcpy(kdb_grep_string, cp);
 877	kdb_grepping_flag++;
 878	return;
 879}
 880
 881/*
 882 * kdb_parse - Parse the command line, search the command table for a
 883 *	matching command and invoke the command function.  This
 884 *	function may be called recursively, if it is, the second call
 885 *	will overwrite argv and cbuf.  It is the caller's
 886 *	responsibility to save their argv if they recursively call
 887 *	kdb_parse().
 888 * Parameters:
 889 *      cmdstr	The input command line to be parsed.
 890 *	regs	The registers at the time kdb was entered.
 891 * Returns:
 892 *	Zero for success, a kdb diagnostic if failure.
 893 * Remarks:
 894 *	Limited to 20 tokens.
 895 *
 896 *	Real rudimentary tokenization. Basically only whitespace
 897 *	is considered a token delimeter (but special consideration
 898 *	is taken of the '=' sign as used by the 'set' command).
 899 *
 900 *	The algorithm used to tokenize the input string relies on
 901 *	there being at least one whitespace (or otherwise useless)
 902 *	character between tokens as the character immediately following
 903 *	the token is altered in-place to a null-byte to terminate the
 904 *	token string.
 905 */
 906
 907#define MAXARGC	20
 908
 909int kdb_parse(const char *cmdstr)
 910{
 911	static char *argv[MAXARGC];
 912	static int argc;
 913	static char cbuf[CMD_BUFLEN+2];
 914	char *cp;
 915	char *cpp, quoted;
 916	kdbtab_t *tp;
 917	int i, escaped, ignore_errors = 0, check_grep = 0;
 918
 919	/*
 920	 * First tokenize the command string.
 921	 */
 922	cp = (char *)cmdstr;
 923
 924	if (KDB_FLAG(CMD_INTERRUPT)) {
 925		/* Previous command was interrupted, newline must not
 926		 * repeat the command */
 927		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 928		KDB_STATE_SET(PAGER);
 929		argc = 0;	/* no repeat */
 930	}
 931
 932	if (*cp != '\n' && *cp != '\0') {
 933		argc = 0;
 934		cpp = cbuf;
 935		while (*cp) {
 936			/* skip whitespace */
 937			while (isspace(*cp))
 938				cp++;
 939			if ((*cp == '\0') || (*cp == '\n') ||
 940			    (*cp == '#' && !defcmd_in_progress))
 941				break;
 942			/* special case: check for | grep pattern */
 943			if (*cp == '|') {
 944				check_grep++;
 945				break;
 946			}
 947			if (cpp >= cbuf + CMD_BUFLEN) {
 948				kdb_printf("kdb_parse: command buffer "
 949					   "overflow, command ignored\n%s\n",
 950					   cmdstr);
 951				return KDB_NOTFOUND;
 952			}
 953			if (argc >= MAXARGC - 1) {
 954				kdb_printf("kdb_parse: too many arguments, "
 955					   "command ignored\n%s\n", cmdstr);
 956				return KDB_NOTFOUND;
 957			}
 958			argv[argc++] = cpp;
 959			escaped = 0;
 960			quoted = '\0';
 961			/* Copy to next unquoted and unescaped
 962			 * whitespace or '=' */
 963			while (*cp && *cp != '\n' &&
 964			       (escaped || quoted || !isspace(*cp))) {
 965				if (cpp >= cbuf + CMD_BUFLEN)
 966					break;
 967				if (escaped) {
 968					escaped = 0;
 969					*cpp++ = *cp++;
 970					continue;
 971				}
 972				if (*cp == '\\') {
 973					escaped = 1;
 974					++cp;
 975					continue;
 976				}
 977				if (*cp == quoted)
 978					quoted = '\0';
 979				else if (*cp == '\'' || *cp == '"')
 980					quoted = *cp;
 981				*cpp = *cp++;
 982				if (*cpp == '=' && !quoted)
 983					break;
 984				++cpp;
 985			}
 986			*cpp++ = '\0';	/* Squash a ws or '=' character */
 987		}
 988	}
 989	if (!argc)
 990		return 0;
 991	if (check_grep)
 992		parse_grep(cp);
 993	if (defcmd_in_progress) {
 994		int result = kdb_defcmd2(cmdstr, argv[0]);
 995		if (!defcmd_in_progress) {
 996			argc = 0;	/* avoid repeat on endefcmd */
 997			*(argv[0]) = '\0';
 998		}
 999		return result;
1000	}
1001	if (argv[0][0] == '-' && argv[0][1] &&
1002	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1003		ignore_errors = 1;
1004		++argv[0];
1005	}
1006
1007	for_each_kdbcmd(tp, i) {
1008		if (tp->cmd_name) {
1009			/*
1010			 * If this command is allowed to be abbreviated,
1011			 * check to see if this is it.
1012			 */
1013
1014			if (tp->cmd_minlen
1015			 && (strlen(argv[0]) <= tp->cmd_minlen)) {
1016				if (strncmp(argv[0],
1017					    tp->cmd_name,
1018					    tp->cmd_minlen) == 0) {
1019					break;
1020				}
1021			}
1022
1023			if (strcmp(argv[0], tp->cmd_name) == 0)
1024				break;
1025		}
1026	}
1027
1028	/*
1029	 * If we don't find a command by this name, see if the first
1030	 * few characters of this match any of the known commands.
1031	 * e.g., md1c20 should match md.
1032	 */
1033	if (i == kdb_max_commands) {
1034		for_each_kdbcmd(tp, i) {
1035			if (tp->cmd_name) {
1036				if (strncmp(argv[0],
1037					    tp->cmd_name,
1038					    strlen(tp->cmd_name)) == 0) {
1039					break;
1040				}
1041			}
1042		}
1043	}
1044
1045	if (i < kdb_max_commands) {
1046		int result;
1047
1048		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1049			return KDB_NOPERM;
1050
1051		KDB_STATE_SET(CMD);
1052		result = (*tp->cmd_func)(argc-1, (const char **)argv);
1053		if (result && ignore_errors && result > KDB_CMD_GO)
1054			result = 0;
1055		KDB_STATE_CLEAR(CMD);
1056
1057		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1058			return result;
1059
1060		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1061		if (argv[argc])
1062			*(argv[argc]) = '\0';
1063		return result;
1064	}
1065
1066	/*
1067	 * If the input with which we were presented does not
1068	 * map to an existing command, attempt to parse it as an
1069	 * address argument and display the result.   Useful for
1070	 * obtaining the address of a variable, or the nearest symbol
1071	 * to an address contained in a register.
1072	 */
1073	{
1074		unsigned long value;
1075		char *name = NULL;
1076		long offset;
1077		int nextarg = 0;
1078
1079		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1080				  &value, &offset, &name)) {
1081			return KDB_NOTFOUND;
1082		}
1083
1084		kdb_printf("%s = ", argv[0]);
1085		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1086		kdb_printf("\n");
1087		return 0;
1088	}
1089}
1090
1091
1092static int handle_ctrl_cmd(char *cmd)
1093{
1094#define CTRL_P	16
1095#define CTRL_N	14
1096
1097	/* initial situation */
1098	if (cmd_head == cmd_tail)
1099		return 0;
1100	switch (*cmd) {
1101	case CTRL_P:
1102		if (cmdptr != cmd_tail)
1103			cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
1104		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1105		return 1;
1106	case CTRL_N:
1107		if (cmdptr != cmd_head)
1108			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1109		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1110		return 1;
1111	}
1112	return 0;
1113}
1114
1115/*
1116 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1117 *	the system immediately, or loop for ever on failure.
1118 */
1119static int kdb_reboot(int argc, const char **argv)
1120{
1121	emergency_restart();
1122	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1123	while (1)
1124		cpu_relax();
1125	/* NOTREACHED */
1126	return 0;
1127}
1128
1129static void kdb_dumpregs(struct pt_regs *regs)
1130{
1131	int old_lvl = console_loglevel;
1132	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1133	kdb_trap_printk++;
1134	show_regs(regs);
1135	kdb_trap_printk--;
1136	kdb_printf("\n");
1137	console_loglevel = old_lvl;
1138}
1139
1140void kdb_set_current_task(struct task_struct *p)
1141{
1142	kdb_current_task = p;
1143
1144	if (kdb_task_has_cpu(p)) {
1145		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1146		return;
1147	}
1148	kdb_current_regs = NULL;
1149}
1150
 
 
 
 
 
 
 
 
 
 
1151/*
1152 * kdb_local - The main code for kdb.  This routine is invoked on a
1153 *	specific processor, it is not global.  The main kdb() routine
1154 *	ensures that only one processor at a time is in this routine.
1155 *	This code is called with the real reason code on the first
1156 *	entry to a kdb session, thereafter it is called with reason
1157 *	SWITCH, even if the user goes back to the original cpu.
1158 * Inputs:
1159 *	reason		The reason KDB was invoked
1160 *	error		The hardware-defined error code
1161 *	regs		The exception frame at time of fault/breakpoint.
1162 *	db_result	Result code from the break or debug point.
1163 * Returns:
1164 *	0	KDB was invoked for an event which it wasn't responsible
1165 *	1	KDB handled the event for which it was invoked.
1166 *	KDB_CMD_GO	User typed 'go'.
1167 *	KDB_CMD_CPU	User switched to another cpu.
1168 *	KDB_CMD_SS	Single step.
1169 */
1170static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1171		     kdb_dbtrap_t db_result)
1172{
1173	char *cmdbuf;
1174	int diag;
1175	struct task_struct *kdb_current =
1176		kdb_curr_task(raw_smp_processor_id());
1177
1178	KDB_DEBUG_STATE("kdb_local 1", reason);
1179	kdb_go_count = 0;
1180	if (reason == KDB_REASON_DEBUG) {
1181		/* special case below */
1182	} else {
1183		kdb_printf("\nEntering kdb (current=0x%p, pid %d) ",
1184			   kdb_current, kdb_current ? kdb_current->pid : 0);
1185#if defined(CONFIG_SMP)
1186		kdb_printf("on processor %d ", raw_smp_processor_id());
1187#endif
1188	}
1189
1190	switch (reason) {
1191	case KDB_REASON_DEBUG:
1192	{
1193		/*
1194		 * If re-entering kdb after a single step
1195		 * command, don't print the message.
1196		 */
1197		switch (db_result) {
1198		case KDB_DB_BPT:
1199			kdb_printf("\nEntering kdb (0x%p, pid %d) ",
1200				   kdb_current, kdb_current->pid);
1201#if defined(CONFIG_SMP)
1202			kdb_printf("on processor %d ", raw_smp_processor_id());
1203#endif
1204			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1205				   instruction_pointer(regs));
1206			break;
1207		case KDB_DB_SS:
1208			break;
1209		case KDB_DB_SSBPT:
1210			KDB_DEBUG_STATE("kdb_local 4", reason);
1211			return 1;	/* kdba_db_trap did the work */
1212		default:
1213			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1214				   db_result);
1215			break;
1216		}
1217
1218	}
1219		break;
1220	case KDB_REASON_ENTER:
1221		if (KDB_STATE(KEYBOARD))
1222			kdb_printf("due to Keyboard Entry\n");
1223		else
1224			kdb_printf("due to KDB_ENTER()\n");
1225		break;
1226	case KDB_REASON_KEYBOARD:
1227		KDB_STATE_SET(KEYBOARD);
1228		kdb_printf("due to Keyboard Entry\n");
1229		break;
1230	case KDB_REASON_ENTER_SLAVE:
1231		/* drop through, slaves only get released via cpu switch */
1232	case KDB_REASON_SWITCH:
1233		kdb_printf("due to cpu switch\n");
1234		break;
1235	case KDB_REASON_OOPS:
1236		kdb_printf("Oops: %s\n", kdb_diemsg);
1237		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1238			   instruction_pointer(regs));
1239		kdb_dumpregs(regs);
1240		break;
1241	case KDB_REASON_SYSTEM_NMI:
1242		kdb_printf("due to System NonMaskable Interrupt\n");
1243		break;
1244	case KDB_REASON_NMI:
1245		kdb_printf("due to NonMaskable Interrupt @ "
1246			   kdb_machreg_fmt "\n",
1247			   instruction_pointer(regs));
1248		break;
1249	case KDB_REASON_SSTEP:
1250	case KDB_REASON_BREAK:
1251		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1252			   reason == KDB_REASON_BREAK ?
1253			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1254		/*
1255		 * Determine if this breakpoint is one that we
1256		 * are interested in.
1257		 */
1258		if (db_result != KDB_DB_BPT) {
1259			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1260				   db_result);
1261			KDB_DEBUG_STATE("kdb_local 6", reason);
1262			return 0;	/* Not for us, dismiss it */
1263		}
1264		break;
1265	case KDB_REASON_RECURSE:
1266		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1267			   instruction_pointer(regs));
1268		break;
1269	default:
1270		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1271		KDB_DEBUG_STATE("kdb_local 8", reason);
1272		return 0;	/* Not for us, dismiss it */
1273	}
1274
1275	while (1) {
1276		/*
1277		 * Initialize pager context.
1278		 */
1279		kdb_nextline = 1;
1280		KDB_STATE_CLEAR(SUPPRESS);
1281		kdb_grepping_flag = 0;
1282		/* ensure the old search does not leak into '/' commands */
1283		kdb_grep_string[0] = '\0';
1284
1285		cmdbuf = cmd_cur;
1286		*cmdbuf = '\0';
1287		*(cmd_hist[cmd_head]) = '\0';
1288
1289do_full_getstr:
1290#if defined(CONFIG_SMP)
1291		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1292			 raw_smp_processor_id());
1293#else
1294		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
1295#endif
1296		if (defcmd_in_progress)
1297			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1298
1299		/*
1300		 * Fetch command from keyboard
1301		 */
1302		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1303		if (*cmdbuf != '\n') {
1304			if (*cmdbuf < 32) {
1305				if (cmdptr == cmd_head) {
1306					strncpy(cmd_hist[cmd_head], cmd_cur,
1307						CMD_BUFLEN);
1308					*(cmd_hist[cmd_head] +
1309					  strlen(cmd_hist[cmd_head])-1) = '\0';
1310				}
1311				if (!handle_ctrl_cmd(cmdbuf))
1312					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1313				cmdbuf = cmd_cur;
1314				goto do_full_getstr;
1315			} else {
1316				strncpy(cmd_hist[cmd_head], cmd_cur,
1317					CMD_BUFLEN);
1318			}
1319
1320			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1321			if (cmd_head == cmd_tail)
1322				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1323		}
1324
1325		cmdptr = cmd_head;
1326		diag = kdb_parse(cmdbuf);
1327		if (diag == KDB_NOTFOUND) {
 
1328			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1329			diag = 0;
1330		}
1331		if (diag == KDB_CMD_GO
1332		 || diag == KDB_CMD_CPU
1333		 || diag == KDB_CMD_SS
1334		 || diag == KDB_CMD_KGDB)
1335			break;
1336
1337		if (diag)
1338			kdb_cmderror(diag);
1339	}
1340	KDB_DEBUG_STATE("kdb_local 9", diag);
1341	return diag;
1342}
1343
1344
1345/*
1346 * kdb_print_state - Print the state data for the current processor
1347 *	for debugging.
1348 * Inputs:
1349 *	text		Identifies the debug point
1350 *	value		Any integer value to be printed, e.g. reason code.
1351 */
1352void kdb_print_state(const char *text, int value)
1353{
1354	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1355		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1356		   kdb_state);
1357}
1358
1359/*
1360 * kdb_main_loop - After initial setup and assignment of the
1361 *	controlling cpu, all cpus are in this loop.  One cpu is in
1362 *	control and will issue the kdb prompt, the others will spin
1363 *	until 'go' or cpu switch.
1364 *
1365 *	To get a consistent view of the kernel stacks for all
1366 *	processes, this routine is invoked from the main kdb code via
1367 *	an architecture specific routine.  kdba_main_loop is
1368 *	responsible for making the kernel stacks consistent for all
1369 *	processes, there should be no difference between a blocked
1370 *	process and a running process as far as kdb is concerned.
1371 * Inputs:
1372 *	reason		The reason KDB was invoked
1373 *	error		The hardware-defined error code
1374 *	reason2		kdb's current reason code.
1375 *			Initially error but can change
1376 *			according to kdb state.
1377 *	db_result	Result code from break or debug point.
1378 *	regs		The exception frame at time of fault/breakpoint.
1379 *			should always be valid.
1380 * Returns:
1381 *	0	KDB was invoked for an event which it wasn't responsible
1382 *	1	KDB handled the event for which it was invoked.
1383 */
1384int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1385	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1386{
1387	int result = 1;
1388	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1389	while (1) {
1390		/*
1391		 * All processors except the one that is in control
1392		 * will spin here.
1393		 */
1394		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1395		while (KDB_STATE(HOLD_CPU)) {
1396			/* state KDB is turned off by kdb_cpu to see if the
1397			 * other cpus are still live, each cpu in this loop
1398			 * turns it back on.
1399			 */
1400			if (!KDB_STATE(KDB))
1401				KDB_STATE_SET(KDB);
1402		}
1403
1404		KDB_STATE_CLEAR(SUPPRESS);
1405		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1406		if (KDB_STATE(LEAVING))
1407			break;	/* Another cpu said 'go' */
1408		/* Still using kdb, this processor is in control */
1409		result = kdb_local(reason2, error, regs, db_result);
1410		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1411
1412		if (result == KDB_CMD_CPU)
1413			break;
1414
1415		if (result == KDB_CMD_SS) {
1416			KDB_STATE_SET(DOING_SS);
1417			break;
1418		}
1419
1420		if (result == KDB_CMD_KGDB) {
1421			if (!KDB_STATE(DOING_KGDB))
1422				kdb_printf("Entering please attach debugger "
1423					   "or use $D#44+ or $3#33\n");
1424			break;
1425		}
1426		if (result && result != 1 && result != KDB_CMD_GO)
1427			kdb_printf("\nUnexpected kdb_local return code %d\n",
1428				   result);
1429		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1430		break;
1431	}
1432	if (KDB_STATE(DOING_SS))
1433		KDB_STATE_CLEAR(SSBPT);
1434
1435	/* Clean up any keyboard devices before leaving */
1436	kdb_kbd_cleanup_state();
1437
1438	return result;
1439}
1440
1441/*
1442 * kdb_mdr - This function implements the guts of the 'mdr', memory
1443 * read command.
1444 *	mdr  <addr arg>,<byte count>
1445 * Inputs:
1446 *	addr	Start address
1447 *	count	Number of bytes
1448 * Returns:
1449 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1450 */
1451static int kdb_mdr(unsigned long addr, unsigned int count)
1452{
1453	unsigned char c;
1454	while (count--) {
1455		if (kdb_getarea(c, addr))
1456			return 0;
1457		kdb_printf("%02x", c);
1458		addr++;
1459	}
1460	kdb_printf("\n");
1461	return 0;
1462}
1463
1464/*
1465 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1466 *	'md8' 'mdr' and 'mds' commands.
1467 *
1468 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1469 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1470 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1471 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1472 *	mdr  <addr arg>,<byte count>
1473 */
1474static void kdb_md_line(const char *fmtstr, unsigned long addr,
1475			int symbolic, int nosect, int bytesperword,
1476			int num, int repeat, int phys)
1477{
1478	/* print just one line of data */
1479	kdb_symtab_t symtab;
1480	char cbuf[32];
1481	char *c = cbuf;
1482	int i;
1483	unsigned long word;
1484
1485	memset(cbuf, '\0', sizeof(cbuf));
1486	if (phys)
1487		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1488	else
1489		kdb_printf(kdb_machreg_fmt0 " ", addr);
1490
1491	for (i = 0; i < num && repeat--; i++) {
1492		if (phys) {
1493			if (kdb_getphysword(&word, addr, bytesperword))
1494				break;
1495		} else if (kdb_getword(&word, addr, bytesperword))
1496			break;
1497		kdb_printf(fmtstr, word);
1498		if (symbolic)
1499			kdbnearsym(word, &symtab);
1500		else
1501			memset(&symtab, 0, sizeof(symtab));
1502		if (symtab.sym_name) {
1503			kdb_symbol_print(word, &symtab, 0);
1504			if (!nosect) {
1505				kdb_printf("\n");
1506				kdb_printf("                       %s %s "
1507					   kdb_machreg_fmt " "
1508					   kdb_machreg_fmt " "
1509					   kdb_machreg_fmt, symtab.mod_name,
1510					   symtab.sec_name, symtab.sec_start,
1511					   symtab.sym_start, symtab.sym_end);
1512			}
1513			addr += bytesperword;
1514		} else {
1515			union {
1516				u64 word;
1517				unsigned char c[8];
1518			} wc;
1519			unsigned char *cp;
1520#ifdef	__BIG_ENDIAN
1521			cp = wc.c + 8 - bytesperword;
1522#else
1523			cp = wc.c;
1524#endif
1525			wc.word = word;
1526#define printable_char(c) \
1527	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1528			switch (bytesperword) {
1529			case 8:
1530				*c++ = printable_char(*cp++);
1531				*c++ = printable_char(*cp++);
1532				*c++ = printable_char(*cp++);
1533				*c++ = printable_char(*cp++);
1534				addr += 4;
1535			case 4:
1536				*c++ = printable_char(*cp++);
1537				*c++ = printable_char(*cp++);
1538				addr += 2;
1539			case 2:
1540				*c++ = printable_char(*cp++);
1541				addr++;
1542			case 1:
1543				*c++ = printable_char(*cp++);
1544				addr++;
1545				break;
1546			}
1547#undef printable_char
1548		}
1549	}
1550	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1551		   " ", cbuf);
1552}
1553
1554static int kdb_md(int argc, const char **argv)
1555{
1556	static unsigned long last_addr;
1557	static int last_radix, last_bytesperword, last_repeat;
1558	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1559	int nosect = 0;
1560	char fmtchar, fmtstr[64];
1561	unsigned long addr;
1562	unsigned long word;
1563	long offset = 0;
1564	int symbolic = 0;
1565	int valid = 0;
1566	int phys = 0;
 
1567
1568	kdbgetintenv("MDCOUNT", &mdcount);
1569	kdbgetintenv("RADIX", &radix);
1570	kdbgetintenv("BYTESPERWORD", &bytesperword);
1571
1572	/* Assume 'md <addr>' and start with environment values */
1573	repeat = mdcount * 16 / bytesperword;
1574
1575	if (strcmp(argv[0], "mdr") == 0) {
1576		if (argc != 2)
 
 
1577			return KDB_ARGCOUNT;
1578		valid = 1;
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		mdcount = ((repeat * bytesperword) + 15) / 16;
 
 
 
1615	}
1616
1617	if (argc) {
1618		unsigned long val;
1619		int diag, nextarg = 1;
1620		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1621				     &offset, NULL);
1622		if (diag)
1623			return diag;
1624		if (argc > nextarg+2)
1625			return KDB_ARGCOUNT;
1626
1627		if (argc >= nextarg) {
1628			diag = kdbgetularg(argv[nextarg], &val);
1629			if (!diag) {
1630				mdcount = (int) val;
1631				repeat = mdcount * 16 / bytesperword;
 
 
 
1632			}
1633		}
1634		if (argc >= nextarg+1) {
1635			diag = kdbgetularg(argv[nextarg+1], &val);
1636			if (!diag)
1637				radix = (int) val;
1638		}
1639	}
1640
1641	if (strcmp(argv[0], "mdr") == 0)
1642		return kdb_mdr(addr, mdcount);
 
 
 
 
 
 
 
1643
1644	switch (radix) {
1645	case 10:
1646		fmtchar = 'd';
1647		break;
1648	case 16:
1649		fmtchar = 'x';
1650		break;
1651	case 8:
1652		fmtchar = 'o';
1653		break;
1654	default:
1655		return KDB_BADRADIX;
1656	}
1657
1658	last_radix = radix;
1659
1660	if (bytesperword > KDB_WORD_SIZE)
1661		return KDB_BADWIDTH;
1662
1663	switch (bytesperword) {
1664	case 8:
1665		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1666		break;
1667	case 4:
1668		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1669		break;
1670	case 2:
1671		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1672		break;
1673	case 1:
1674		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1675		break;
1676	default:
1677		return KDB_BADWIDTH;
1678	}
1679
1680	last_repeat = repeat;
1681	last_bytesperword = bytesperword;
1682
1683	if (strcmp(argv[0], "mds") == 0) {
1684		symbolic = 1;
1685		/* Do not save these changes as last_*, they are temporary mds
1686		 * overrides.
1687		 */
1688		bytesperword = KDB_WORD_SIZE;
1689		repeat = mdcount;
1690		kdbgetintenv("NOSECT", &nosect);
1691	}
1692
1693	/* Round address down modulo BYTESPERWORD */
1694
1695	addr &= ~(bytesperword-1);
1696
1697	while (repeat > 0) {
1698		unsigned long a;
1699		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1700
1701		if (KDB_FLAG(CMD_INTERRUPT))
1702			return 0;
1703		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1704			if (phys) {
1705				if (kdb_getphysword(&word, a, bytesperword)
1706						|| word)
1707					break;
1708			} else if (kdb_getword(&word, a, bytesperword) || word)
1709				break;
1710		}
1711		n = min(num, repeat);
1712		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1713			    num, repeat, phys);
1714		addr += bytesperword * n;
1715		repeat -= n;
1716		z = (z + num - 1) / num;
1717		if (z > 2) {
1718			int s = num * (z-2);
1719			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1720				   " zero suppressed\n",
1721				addr, addr + bytesperword * s - 1);
1722			addr += bytesperword * s;
1723			repeat -= s;
1724		}
1725	}
1726	last_addr = addr;
1727
1728	return 0;
1729}
1730
1731/*
1732 * kdb_mm - This function implements the 'mm' command.
1733 *	mm address-expression new-value
1734 * Remarks:
1735 *	mm works on machine words, mmW works on bytes.
1736 */
1737static int kdb_mm(int argc, const char **argv)
1738{
1739	int diag;
1740	unsigned long addr;
1741	long offset = 0;
1742	unsigned long contents;
1743	int nextarg;
1744	int width;
1745
1746	if (argv[0][2] && !isdigit(argv[0][2]))
1747		return KDB_NOTFOUND;
1748
1749	if (argc < 2)
1750		return KDB_ARGCOUNT;
1751
1752	nextarg = 1;
1753	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1754	if (diag)
1755		return diag;
1756
1757	if (nextarg > argc)
1758		return KDB_ARGCOUNT;
1759	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1760	if (diag)
1761		return diag;
1762
1763	if (nextarg != argc + 1)
1764		return KDB_ARGCOUNT;
1765
1766	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1767	diag = kdb_putword(addr, contents, width);
1768	if (diag)
1769		return diag;
1770
1771	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1772
1773	return 0;
1774}
1775
1776/*
1777 * kdb_go - This function implements the 'go' command.
1778 *	go [address-expression]
1779 */
1780static int kdb_go(int argc, const char **argv)
1781{
1782	unsigned long addr;
1783	int diag;
1784	int nextarg;
1785	long offset;
1786
1787	if (raw_smp_processor_id() != kdb_initial_cpu) {
1788		kdb_printf("go must execute on the entry cpu, "
1789			   "please use \"cpu %d\" and then execute go\n",
1790			   kdb_initial_cpu);
1791		return KDB_BADCPUNUM;
1792	}
1793	if (argc == 1) {
1794		nextarg = 1;
1795		diag = kdbgetaddrarg(argc, argv, &nextarg,
1796				     &addr, &offset, NULL);
1797		if (diag)
1798			return diag;
1799	} else if (argc) {
1800		return KDB_ARGCOUNT;
1801	}
1802
1803	diag = KDB_CMD_GO;
1804	if (KDB_FLAG(CATASTROPHIC)) {
1805		kdb_printf("Catastrophic error detected\n");
1806		kdb_printf("kdb_continue_catastrophic=%d, ",
1807			kdb_continue_catastrophic);
1808		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1809			kdb_printf("type go a second time if you really want "
1810				   "to continue\n");
1811			return 0;
1812		}
1813		if (kdb_continue_catastrophic == 2) {
1814			kdb_printf("forcing reboot\n");
1815			kdb_reboot(0, NULL);
1816		}
1817		kdb_printf("attempting to continue\n");
1818	}
1819	return diag;
1820}
1821
1822/*
1823 * kdb_rd - This function implements the 'rd' command.
1824 */
1825static int kdb_rd(int argc, const char **argv)
1826{
1827	int len = kdb_check_regs();
1828#if DBG_MAX_REG_NUM > 0
1829	int i;
1830	char *rname;
1831	int rsize;
1832	u64 reg64;
1833	u32 reg32;
1834	u16 reg16;
1835	u8 reg8;
1836
1837	if (len)
1838		return len;
1839
1840	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1841		rsize = dbg_reg_def[i].size * 2;
1842		if (rsize > 16)
1843			rsize = 2;
1844		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1845			len = 0;
1846			kdb_printf("\n");
1847		}
1848		if (len)
1849			len += kdb_printf("  ");
1850		switch(dbg_reg_def[i].size * 8) {
1851		case 8:
1852			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1853			if (!rname)
1854				break;
1855			len += kdb_printf("%s: %02x", rname, reg8);
1856			break;
1857		case 16:
1858			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1859			if (!rname)
1860				break;
1861			len += kdb_printf("%s: %04x", rname, reg16);
1862			break;
1863		case 32:
1864			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1865			if (!rname)
1866				break;
1867			len += kdb_printf("%s: %08x", rname, reg32);
1868			break;
1869		case 64:
1870			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1871			if (!rname)
1872				break;
1873			len += kdb_printf("%s: %016llx", rname, reg64);
1874			break;
1875		default:
1876			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1877		}
1878	}
1879	kdb_printf("\n");
1880#else
1881	if (len)
1882		return len;
1883
1884	kdb_dumpregs(kdb_current_regs);
1885#endif
1886	return 0;
1887}
1888
1889/*
1890 * kdb_rm - This function implements the 'rm' (register modify)  command.
1891 *	rm register-name new-contents
1892 * Remarks:
1893 *	Allows register modification with the same restrictions as gdb
1894 */
1895static int kdb_rm(int argc, const char **argv)
1896{
1897#if DBG_MAX_REG_NUM > 0
1898	int diag;
1899	const char *rname;
1900	int i;
1901	u64 reg64;
1902	u32 reg32;
1903	u16 reg16;
1904	u8 reg8;
1905
1906	if (argc != 2)
1907		return KDB_ARGCOUNT;
1908	/*
1909	 * Allow presence or absence of leading '%' symbol.
1910	 */
1911	rname = argv[1];
1912	if (*rname == '%')
1913		rname++;
1914
1915	diag = kdbgetu64arg(argv[2], &reg64);
1916	if (diag)
1917		return diag;
1918
1919	diag = kdb_check_regs();
1920	if (diag)
1921		return diag;
1922
1923	diag = KDB_BADREG;
1924	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1925		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1926			diag = 0;
1927			break;
1928		}
1929	}
1930	if (!diag) {
1931		switch(dbg_reg_def[i].size * 8) {
1932		case 8:
1933			reg8 = reg64;
1934			dbg_set_reg(i, &reg8, kdb_current_regs);
1935			break;
1936		case 16:
1937			reg16 = reg64;
1938			dbg_set_reg(i, &reg16, kdb_current_regs);
1939			break;
1940		case 32:
1941			reg32 = reg64;
1942			dbg_set_reg(i, &reg32, kdb_current_regs);
1943			break;
1944		case 64:
1945			dbg_set_reg(i, &reg64, kdb_current_regs);
1946			break;
1947		}
1948	}
1949	return diag;
1950#else
1951	kdb_printf("ERROR: Register set currently not implemented\n");
1952    return 0;
1953#endif
1954}
1955
1956#if defined(CONFIG_MAGIC_SYSRQ)
1957/*
1958 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1959 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1960 *		sr <magic-sysrq-code>
1961 */
1962static int kdb_sr(int argc, const char **argv)
1963{
1964	bool check_mask =
1965	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1966
1967	if (argc != 1)
1968		return KDB_ARGCOUNT;
1969
1970	kdb_trap_printk++;
1971	__handle_sysrq(*argv[1], check_mask);
1972	kdb_trap_printk--;
1973
1974	return 0;
1975}
1976#endif	/* CONFIG_MAGIC_SYSRQ */
1977
1978/*
1979 * kdb_ef - This function implements the 'regs' (display exception
1980 *	frame) command.  This command takes an address and expects to
1981 *	find an exception frame at that address, formats and prints
1982 *	it.
1983 *		regs address-expression
1984 * Remarks:
1985 *	Not done yet.
1986 */
1987static int kdb_ef(int argc, const char **argv)
1988{
1989	int diag;
1990	unsigned long addr;
1991	long offset;
1992	int nextarg;
1993
1994	if (argc != 1)
1995		return KDB_ARGCOUNT;
1996
1997	nextarg = 1;
1998	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1999	if (diag)
2000		return diag;
2001	show_regs((struct pt_regs *)addr);
2002	return 0;
2003}
2004
2005#if defined(CONFIG_MODULES)
2006/*
2007 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2008 *	currently loaded kernel modules.
2009 *	Mostly taken from userland lsmod.
2010 */
2011static int kdb_lsmod(int argc, const char **argv)
2012{
2013	struct module *mod;
2014
2015	if (argc != 0)
2016		return KDB_ARGCOUNT;
2017
2018	kdb_printf("Module                  Size  modstruct     Used by\n");
2019	list_for_each_entry(mod, kdb_modules, list) {
2020		if (mod->state == MODULE_STATE_UNFORMED)
2021			continue;
2022
2023		kdb_printf("%-20s%8u  0x%p ", mod->name,
2024			   mod->core_layout.size, (void *)mod);
2025#ifdef CONFIG_MODULE_UNLOAD
2026		kdb_printf("%4d ", module_refcount(mod));
2027#endif
2028		if (mod->state == MODULE_STATE_GOING)
2029			kdb_printf(" (Unloading)");
2030		else if (mod->state == MODULE_STATE_COMING)
2031			kdb_printf(" (Loading)");
2032		else
2033			kdb_printf(" (Live)");
2034		kdb_printf(" 0x%p", mod->core_layout.base);
2035
2036#ifdef CONFIG_MODULE_UNLOAD
2037		{
2038			struct module_use *use;
2039			kdb_printf(" [ ");
2040			list_for_each_entry(use, &mod->source_list,
2041					    source_list)
2042				kdb_printf("%s ", use->target->name);
2043			kdb_printf("]\n");
2044		}
2045#endif
2046	}
2047
2048	return 0;
2049}
2050
2051#endif	/* CONFIG_MODULES */
2052
2053/*
2054 * kdb_env - This function implements the 'env' command.  Display the
2055 *	current environment variables.
2056 */
2057
2058static int kdb_env(int argc, const char **argv)
2059{
2060	int i;
2061
2062	for (i = 0; i < __nenv; i++) {
2063		if (__env[i])
2064			kdb_printf("%s\n", __env[i]);
2065	}
2066
2067	if (KDB_DEBUG(MASK))
2068		kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
2069
2070	return 0;
2071}
2072
2073#ifdef CONFIG_PRINTK
2074/*
2075 * kdb_dmesg - This function implements the 'dmesg' command to display
2076 *	the contents of the syslog buffer.
2077 *		dmesg [lines] [adjust]
2078 */
2079static int kdb_dmesg(int argc, const char **argv)
2080{
2081	int diag;
2082	int logging;
2083	int lines = 0;
2084	int adjust = 0;
2085	int n = 0;
2086	int skip = 0;
2087	struct kmsg_dumper dumper = { .active = 1 };
2088	size_t len;
2089	char buf[201];
2090
2091	if (argc > 2)
2092		return KDB_ARGCOUNT;
2093	if (argc) {
2094		char *cp;
2095		lines = simple_strtol(argv[1], &cp, 0);
2096		if (*cp)
2097			lines = 0;
2098		if (argc > 1) {
2099			adjust = simple_strtoul(argv[2], &cp, 0);
2100			if (*cp || adjust < 0)
2101				adjust = 0;
2102		}
2103	}
2104
2105	/* disable LOGGING if set */
2106	diag = kdbgetintenv("LOGGING", &logging);
2107	if (!diag && logging) {
2108		const char *setargs[] = { "set", "LOGGING", "0" };
2109		kdb_set(2, setargs);
2110	}
2111
2112	kmsg_dump_rewind_nolock(&dumper);
2113	while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
2114		n++;
2115
2116	if (lines < 0) {
2117		if (adjust >= n)
2118			kdb_printf("buffer only contains %d lines, nothing "
2119				   "printed\n", n);
2120		else if (adjust - lines >= n)
2121			kdb_printf("buffer only contains %d lines, last %d "
2122				   "lines printed\n", n, n - adjust);
2123		skip = adjust;
2124		lines = abs(lines);
2125	} else if (lines > 0) {
2126		skip = n - lines - adjust;
2127		lines = abs(lines);
2128		if (adjust >= n) {
2129			kdb_printf("buffer only contains %d lines, "
2130				   "nothing printed\n", n);
2131			skip = n;
2132		} else if (skip < 0) {
2133			lines += skip;
2134			skip = 0;
2135			kdb_printf("buffer only contains %d lines, first "
2136				   "%d lines printed\n", n, lines);
2137		}
2138	} else {
2139		lines = n;
2140	}
2141
2142	if (skip >= n || skip < 0)
2143		return 0;
2144
2145	kmsg_dump_rewind_nolock(&dumper);
2146	while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
2147		if (skip) {
2148			skip--;
2149			continue;
2150		}
2151		if (!lines--)
2152			break;
2153		if (KDB_FLAG(CMD_INTERRUPT))
2154			return 0;
2155
2156		kdb_printf("%.*s\n", (int)len - 1, buf);
2157	}
2158
2159	return 0;
2160}
2161#endif /* CONFIG_PRINTK */
2162
2163/* Make sure we balance enable/disable calls, must disable first. */
2164static atomic_t kdb_nmi_disabled;
2165
2166static int kdb_disable_nmi(int argc, const char *argv[])
2167{
2168	if (atomic_read(&kdb_nmi_disabled))
2169		return 0;
2170	atomic_set(&kdb_nmi_disabled, 1);
2171	arch_kgdb_ops.enable_nmi(0);
2172	return 0;
2173}
2174
2175static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2176{
2177	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2178		return -EINVAL;
2179	arch_kgdb_ops.enable_nmi(1);
2180	return 0;
2181}
2182
2183static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2184	.set = kdb_param_enable_nmi,
2185};
2186module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2187
2188/*
2189 * kdb_cpu - This function implements the 'cpu' command.
2190 *	cpu	[<cpunum>]
2191 * Returns:
2192 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2193 */
2194static void kdb_cpu_status(void)
2195{
2196	int i, start_cpu, first_print = 1;
2197	char state, prev_state = '?';
2198
2199	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2200	kdb_printf("Available cpus: ");
2201	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2202		if (!cpu_online(i)) {
2203			state = 'F';	/* cpu is offline */
2204		} else if (!kgdb_info[i].enter_kgdb) {
2205			state = 'D';	/* cpu is online but unresponsive */
2206		} else {
2207			state = ' ';	/* cpu is responding to kdb */
2208			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2209				state = 'I';	/* idle task */
2210		}
2211		if (state != prev_state) {
2212			if (prev_state != '?') {
2213				if (!first_print)
2214					kdb_printf(", ");
2215				first_print = 0;
2216				kdb_printf("%d", start_cpu);
2217				if (start_cpu < i-1)
2218					kdb_printf("-%d", i-1);
2219				if (prev_state != ' ')
2220					kdb_printf("(%c)", prev_state);
2221			}
2222			prev_state = state;
2223			start_cpu = i;
2224		}
2225	}
2226	/* print the trailing cpus, ignoring them if they are all offline */
2227	if (prev_state != 'F') {
2228		if (!first_print)
2229			kdb_printf(", ");
2230		kdb_printf("%d", start_cpu);
2231		if (start_cpu < i-1)
2232			kdb_printf("-%d", i-1);
2233		if (prev_state != ' ')
2234			kdb_printf("(%c)", prev_state);
2235	}
2236	kdb_printf("\n");
2237}
2238
2239static int kdb_cpu(int argc, const char **argv)
2240{
2241	unsigned long cpunum;
2242	int diag;
2243
2244	if (argc == 0) {
2245		kdb_cpu_status();
2246		return 0;
2247	}
2248
2249	if (argc != 1)
2250		return KDB_ARGCOUNT;
2251
2252	diag = kdbgetularg(argv[1], &cpunum);
2253	if (diag)
2254		return diag;
2255
2256	/*
2257	 * Validate cpunum
2258	 */
2259	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2260		return KDB_BADCPUNUM;
2261
2262	dbg_switch_cpu = cpunum;
2263
2264	/*
2265	 * Switch to other cpu
2266	 */
2267	return KDB_CMD_CPU;
2268}
2269
2270/* The user may not realize that ps/bta with no parameters does not print idle
2271 * or sleeping system daemon processes, so tell them how many were suppressed.
2272 */
2273void kdb_ps_suppressed(void)
2274{
2275	int idle = 0, daemon = 0;
2276	unsigned long mask_I = kdb_task_state_string("I"),
2277		      mask_M = kdb_task_state_string("M");
2278	unsigned long cpu;
2279	const struct task_struct *p, *g;
2280	for_each_online_cpu(cpu) {
2281		p = kdb_curr_task(cpu);
2282		if (kdb_task_state(p, mask_I))
2283			++idle;
2284	}
2285	kdb_do_each_thread(g, p) {
2286		if (kdb_task_state(p, mask_M))
2287			++daemon;
2288	} kdb_while_each_thread(g, p);
2289	if (idle || daemon) {
2290		if (idle)
2291			kdb_printf("%d idle process%s (state I)%s\n",
2292				   idle, idle == 1 ? "" : "es",
2293				   daemon ? " and " : "");
2294		if (daemon)
2295			kdb_printf("%d sleeping system daemon (state M) "
2296				   "process%s", daemon,
2297				   daemon == 1 ? "" : "es");
2298		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2299	}
2300}
2301
2302/*
2303 * kdb_ps - This function implements the 'ps' command which shows a
2304 *	list of the active processes.
2305 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2306 */
2307void kdb_ps1(const struct task_struct *p)
2308{
2309	int cpu;
2310	unsigned long tmp;
2311
2312	if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
2313		return;
2314
2315	cpu = kdb_process_cpu(p);
2316	kdb_printf("0x%p %8d %8d  %d %4d   %c  0x%p %c%s\n",
2317		   (void *)p, p->pid, p->parent->pid,
2318		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2319		   kdb_task_state_char(p),
2320		   (void *)(&p->thread),
2321		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2322		   p->comm);
2323	if (kdb_task_has_cpu(p)) {
2324		if (!KDB_TSK(cpu)) {
2325			kdb_printf("  Error: no saved data for this cpu\n");
2326		} else {
2327			if (KDB_TSK(cpu) != p)
2328				kdb_printf("  Error: does not match running "
2329				   "process table (0x%p)\n", KDB_TSK(cpu));
2330		}
2331	}
2332}
2333
2334static int kdb_ps(int argc, const char **argv)
2335{
2336	struct task_struct *g, *p;
2337	unsigned long mask, cpu;
2338
2339	if (argc == 0)
2340		kdb_ps_suppressed();
2341	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2342		(int)(2*sizeof(void *))+2, "Task Addr",
2343		(int)(2*sizeof(void *))+2, "Thread");
2344	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2345	/* Run the active tasks first */
2346	for_each_online_cpu(cpu) {
2347		if (KDB_FLAG(CMD_INTERRUPT))
2348			return 0;
2349		p = kdb_curr_task(cpu);
2350		if (kdb_task_state(p, mask))
2351			kdb_ps1(p);
2352	}
2353	kdb_printf("\n");
2354	/* Now the real tasks */
2355	kdb_do_each_thread(g, p) {
2356		if (KDB_FLAG(CMD_INTERRUPT))
2357			return 0;
2358		if (kdb_task_state(p, mask))
2359			kdb_ps1(p);
2360	} kdb_while_each_thread(g, p);
2361
2362	return 0;
2363}
2364
2365/*
2366 * kdb_pid - This function implements the 'pid' command which switches
2367 *	the currently active process.
2368 *		pid [<pid> | R]
2369 */
2370static int kdb_pid(int argc, const char **argv)
2371{
2372	struct task_struct *p;
2373	unsigned long val;
2374	int diag;
2375
2376	if (argc > 1)
2377		return KDB_ARGCOUNT;
2378
2379	if (argc) {
2380		if (strcmp(argv[1], "R") == 0) {
2381			p = KDB_TSK(kdb_initial_cpu);
2382		} else {
2383			diag = kdbgetularg(argv[1], &val);
2384			if (diag)
2385				return KDB_BADINT;
2386
2387			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2388			if (!p) {
2389				kdb_printf("No task with pid=%d\n", (pid_t)val);
2390				return 0;
2391			}
2392		}
2393		kdb_set_current_task(p);
2394	}
2395	kdb_printf("KDB current process is %s(pid=%d)\n",
2396		   kdb_current_task->comm,
2397		   kdb_current_task->pid);
2398
2399	return 0;
2400}
2401
2402static int kdb_kgdb(int argc, const char **argv)
2403{
2404	return KDB_CMD_KGDB;
2405}
2406
2407/*
2408 * kdb_help - This function implements the 'help' and '?' commands.
2409 */
2410static int kdb_help(int argc, const char **argv)
2411{
2412	kdbtab_t *kt;
2413	int i;
2414
2415	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2416	kdb_printf("-----------------------------"
2417		   "-----------------------------\n");
2418	for_each_kdbcmd(kt, i) {
2419		char *space = "";
2420		if (KDB_FLAG(CMD_INTERRUPT))
2421			return 0;
2422		if (!kt->cmd_name)
2423			continue;
2424		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2425			continue;
2426		if (strlen(kt->cmd_usage) > 20)
2427			space = "\n                                    ";
2428		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2429			   kt->cmd_usage, space, kt->cmd_help);
2430	}
2431	return 0;
2432}
2433
2434/*
2435 * kdb_kill - This function implements the 'kill' commands.
2436 */
2437static int kdb_kill(int argc, const char **argv)
2438{
2439	long sig, pid;
2440	char *endp;
2441	struct task_struct *p;
2442	struct siginfo info;
2443
2444	if (argc != 2)
2445		return KDB_ARGCOUNT;
2446
2447	sig = simple_strtol(argv[1], &endp, 0);
2448	if (*endp)
2449		return KDB_BADINT;
2450	if (sig >= 0) {
2451		kdb_printf("Invalid signal parameter.<-signal>\n");
2452		return 0;
2453	}
2454	sig = -sig;
2455
2456	pid = simple_strtol(argv[2], &endp, 0);
2457	if (*endp)
2458		return KDB_BADINT;
2459	if (pid <= 0) {
2460		kdb_printf("Process ID must be large than 0.\n");
2461		return 0;
2462	}
2463
2464	/* Find the process. */
2465	p = find_task_by_pid_ns(pid, &init_pid_ns);
2466	if (!p) {
2467		kdb_printf("The specified process isn't found.\n");
2468		return 0;
2469	}
2470	p = p->group_leader;
2471	info.si_signo = sig;
2472	info.si_errno = 0;
2473	info.si_code = SI_USER;
2474	info.si_pid = pid;  /* same capabilities as process being signalled */
2475	info.si_uid = 0;    /* kdb has root authority */
2476	kdb_send_sig_info(p, &info);
2477	return 0;
2478}
2479
2480struct kdb_tm {
2481	int tm_sec;	/* seconds */
2482	int tm_min;	/* minutes */
2483	int tm_hour;	/* hours */
2484	int tm_mday;	/* day of the month */
2485	int tm_mon;	/* month */
2486	int tm_year;	/* year */
2487};
2488
2489static void kdb_gmtime(struct timespec *tv, struct kdb_tm *tm)
2490{
2491	/* This will work from 1970-2099, 2100 is not a leap year */
2492	static int mon_day[] = { 31, 29, 31, 30, 31, 30, 31,
2493				 31, 30, 31, 30, 31 };
2494	memset(tm, 0, sizeof(*tm));
2495	tm->tm_sec  = tv->tv_sec % (24 * 60 * 60);
2496	tm->tm_mday = tv->tv_sec / (24 * 60 * 60) +
2497		(2 * 365 + 1); /* shift base from 1970 to 1968 */
2498	tm->tm_min =  tm->tm_sec / 60 % 60;
2499	tm->tm_hour = tm->tm_sec / 60 / 60;
2500	tm->tm_sec =  tm->tm_sec % 60;
2501	tm->tm_year = 68 + 4*(tm->tm_mday / (4*365+1));
2502	tm->tm_mday %= (4*365+1);
2503	mon_day[1] = 29;
2504	while (tm->tm_mday >= mon_day[tm->tm_mon]) {
2505		tm->tm_mday -= mon_day[tm->tm_mon];
2506		if (++tm->tm_mon == 12) {
2507			tm->tm_mon = 0;
2508			++tm->tm_year;
2509			mon_day[1] = 28;
2510		}
2511	}
2512	++tm->tm_mday;
2513}
2514
2515/*
2516 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2517 * I cannot call that code directly from kdb, it has an unconditional
2518 * cli()/sti() and calls routines that take locks which can stop the debugger.
2519 */
2520static void kdb_sysinfo(struct sysinfo *val)
2521{
2522	struct timespec uptime;
2523	ktime_get_ts(&uptime);
2524	memset(val, 0, sizeof(*val));
2525	val->uptime = uptime.tv_sec;
2526	val->loads[0] = avenrun[0];
2527	val->loads[1] = avenrun[1];
2528	val->loads[2] = avenrun[2];
2529	val->procs = nr_threads-1;
2530	si_meminfo(val);
2531
2532	return;
2533}
2534
2535/*
2536 * kdb_summary - This function implements the 'summary' command.
2537 */
2538static int kdb_summary(int argc, const char **argv)
2539{
2540	struct timespec now;
2541	struct kdb_tm tm;
2542	struct sysinfo val;
2543
2544	if (argc)
2545		return KDB_ARGCOUNT;
2546
2547	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2548	kdb_printf("release    %s\n", init_uts_ns.name.release);
2549	kdb_printf("version    %s\n", init_uts_ns.name.version);
2550	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2551	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2552	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2553	kdb_printf("ccversion  %s\n", __stringify(CCVERSION));
2554
2555	now = __current_kernel_time();
2556	kdb_gmtime(&now, &tm);
2557	kdb_printf("date       %04d-%02d-%02d %02d:%02d:%02d "
2558		   "tz_minuteswest %d\n",
2559		1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2560		tm.tm_hour, tm.tm_min, tm.tm_sec,
2561		sys_tz.tz_minuteswest);
2562
2563	kdb_sysinfo(&val);
2564	kdb_printf("uptime     ");
2565	if (val.uptime > (24*60*60)) {
2566		int days = val.uptime / (24*60*60);
2567		val.uptime %= (24*60*60);
2568		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2569	}
2570	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2571
2572	/* lifted from fs/proc/proc_misc.c::loadavg_read_proc() */
2573
2574#define LOAD_INT(x) ((x) >> FSHIFT)
2575#define LOAD_FRAC(x) LOAD_INT(((x) & (FIXED_1-1)) * 100)
2576	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2577		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2578		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2579		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2580#undef LOAD_INT
2581#undef LOAD_FRAC
2582	/* Display in kilobytes */
2583#define K(x) ((x) << (PAGE_SHIFT - 10))
2584	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2585		   "Buffers:        %8lu kB\n",
2586		   K(val.totalram), K(val.freeram), K(val.bufferram));
2587	return 0;
2588}
2589
2590/*
2591 * kdb_per_cpu - This function implements the 'per_cpu' command.
2592 */
2593static int kdb_per_cpu(int argc, const char **argv)
2594{
2595	char fmtstr[64];
2596	int cpu, diag, nextarg = 1;
2597	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2598
2599	if (argc < 1 || argc > 3)
2600		return KDB_ARGCOUNT;
2601
2602	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2603	if (diag)
2604		return diag;
2605
2606	if (argc >= 2) {
2607		diag = kdbgetularg(argv[2], &bytesperword);
2608		if (diag)
2609			return diag;
2610	}
2611	if (!bytesperword)
2612		bytesperword = KDB_WORD_SIZE;
2613	else if (bytesperword > KDB_WORD_SIZE)
2614		return KDB_BADWIDTH;
2615	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2616	if (argc >= 3) {
2617		diag = kdbgetularg(argv[3], &whichcpu);
2618		if (diag)
2619			return diag;
2620		if (!cpu_online(whichcpu)) {
2621			kdb_printf("cpu %ld is not online\n", whichcpu);
2622			return KDB_BADCPUNUM;
2623		}
2624	}
2625
2626	/* Most architectures use __per_cpu_offset[cpu], some use
2627	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2628	 */
2629#ifdef	__per_cpu_offset
2630#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2631#else
2632#ifdef	CONFIG_SMP
2633#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2634#else
2635#define KDB_PCU(cpu) 0
2636#endif
2637#endif
2638	for_each_online_cpu(cpu) {
2639		if (KDB_FLAG(CMD_INTERRUPT))
2640			return 0;
2641
2642		if (whichcpu != ~0UL && whichcpu != cpu)
2643			continue;
2644		addr = symaddr + KDB_PCU(cpu);
2645		diag = kdb_getword(&val, addr, bytesperword);
2646		if (diag) {
2647			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2648				   "read, diag=%d\n", cpu, addr, diag);
2649			continue;
2650		}
2651		kdb_printf("%5d ", cpu);
2652		kdb_md_line(fmtstr, addr,
2653			bytesperword == KDB_WORD_SIZE,
2654			1, bytesperword, 1, 1, 0);
2655	}
2656#undef KDB_PCU
2657	return 0;
2658}
2659
2660/*
2661 * display help for the use of cmd | grep pattern
2662 */
2663static int kdb_grep_help(int argc, const char **argv)
2664{
2665	kdb_printf("Usage of  cmd args | grep pattern:\n");
2666	kdb_printf("  Any command's output may be filtered through an ");
2667	kdb_printf("emulated 'pipe'.\n");
2668	kdb_printf("  'grep' is just a key word.\n");
2669	kdb_printf("  The pattern may include a very limited set of "
2670		   "metacharacters:\n");
2671	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2672	kdb_printf("  And if there are spaces in the pattern, you may "
2673		   "quote it:\n");
2674	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2675		   " or \"^pat tern$\"\n");
2676	return 0;
2677}
2678
2679/*
2680 * kdb_register_flags - This function is used to register a kernel
2681 * 	debugger command.
2682 * Inputs:
2683 *	cmd	Command name
2684 *	func	Function to execute the command
2685 *	usage	A simple usage string showing arguments
2686 *	help	A simple help string describing command
2687 *	repeat	Does the command auto repeat on enter?
2688 * Returns:
2689 *	zero for success, one if a duplicate command.
2690 */
2691#define kdb_command_extend 50	/* arbitrary */
2692int kdb_register_flags(char *cmd,
2693		       kdb_func_t func,
2694		       char *usage,
2695		       char *help,
2696		       short minlen,
2697		       kdb_cmdflags_t flags)
2698{
2699	int i;
2700	kdbtab_t *kp;
2701
2702	/*
2703	 *  Brute force method to determine duplicates
2704	 */
2705	for_each_kdbcmd(kp, i) {
2706		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2707			kdb_printf("Duplicate kdb command registered: "
2708				"%s, func %p help %s\n", cmd, func, help);
2709			return 1;
2710		}
2711	}
2712
2713	/*
2714	 * Insert command into first available location in table
2715	 */
2716	for_each_kdbcmd(kp, i) {
2717		if (kp->cmd_name == NULL)
2718			break;
2719	}
2720
2721	if (i >= kdb_max_commands) {
2722		kdbtab_t *new = kmalloc((kdb_max_commands - KDB_BASE_CMD_MAX +
2723			 kdb_command_extend) * sizeof(*new), GFP_KDB);
2724		if (!new) {
2725			kdb_printf("Could not allocate new kdb_command "
2726				   "table\n");
2727			return 1;
2728		}
2729		if (kdb_commands) {
2730			memcpy(new, kdb_commands,
2731			  (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new));
2732			kfree(kdb_commands);
2733		}
2734		memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0,
2735		       kdb_command_extend * sizeof(*new));
2736		kdb_commands = new;
2737		kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX;
2738		kdb_max_commands += kdb_command_extend;
2739	}
2740
2741	kp->cmd_name   = cmd;
2742	kp->cmd_func   = func;
2743	kp->cmd_usage  = usage;
2744	kp->cmd_help   = help;
2745	kp->cmd_minlen = minlen;
2746	kp->cmd_flags  = flags;
2747
2748	return 0;
2749}
2750EXPORT_SYMBOL_GPL(kdb_register_flags);
2751
2752
2753/*
2754 * kdb_register - Compatibility register function for commands that do
2755 *	not need to specify a repeat state.  Equivalent to
2756 *	kdb_register_flags with flags set to 0.
2757 * Inputs:
2758 *	cmd	Command name
2759 *	func	Function to execute the command
2760 *	usage	A simple usage string showing arguments
2761 *	help	A simple help string describing command
2762 * Returns:
2763 *	zero for success, one if a duplicate command.
2764 */
2765int kdb_register(char *cmd,
2766	     kdb_func_t func,
2767	     char *usage,
2768	     char *help,
2769	     short minlen)
2770{
2771	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2772}
2773EXPORT_SYMBOL_GPL(kdb_register);
2774
2775/*
2776 * kdb_unregister - This function is used to unregister a kernel
2777 *	debugger command.  It is generally called when a module which
2778 *	implements kdb commands is unloaded.
2779 * Inputs:
2780 *	cmd	Command name
2781 * Returns:
2782 *	zero for success, one command not registered.
2783 */
2784int kdb_unregister(char *cmd)
2785{
2786	int i;
2787	kdbtab_t *kp;
2788
2789	/*
2790	 *  find the command.
2791	 */
2792	for_each_kdbcmd(kp, i) {
2793		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2794			kp->cmd_name = NULL;
2795			return 0;
2796		}
2797	}
2798
2799	/* Couldn't find it.  */
2800	return 1;
2801}
2802EXPORT_SYMBOL_GPL(kdb_unregister);
2803
2804/* Initialize the kdb command table. */
2805static void __init kdb_inittab(void)
2806{
2807	int i;
2808	kdbtab_t *kp;
2809
2810	for_each_kdbcmd(kp, i)
2811		kp->cmd_name = NULL;
2812
2813	kdb_register_flags("md", kdb_md, "<vaddr>",
2814	  "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2815	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2816	kdb_register_flags("mdr", kdb_md, "<vaddr> <bytes>",
2817	  "Display Raw Memory", 0,
2818	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2819	kdb_register_flags("mdp", kdb_md, "<paddr> <bytes>",
2820	  "Display Physical Memory", 0,
2821	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2822	kdb_register_flags("mds", kdb_md, "<vaddr>",
2823	  "Display Memory Symbolically", 0,
2824	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2825	kdb_register_flags("mm", kdb_mm, "<vaddr> <contents>",
2826	  "Modify Memory Contents", 0,
2827	  KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS);
2828	kdb_register_flags("go", kdb_go, "[<vaddr>]",
2829	  "Continue Execution", 1,
2830	  KDB_ENABLE_REG_WRITE | KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2831	kdb_register_flags("rd", kdb_rd, "",
2832	  "Display Registers", 0,
2833	  KDB_ENABLE_REG_READ);
2834	kdb_register_flags("rm", kdb_rm, "<reg> <contents>",
2835	  "Modify Registers", 0,
2836	  KDB_ENABLE_REG_WRITE);
2837	kdb_register_flags("ef", kdb_ef, "<vaddr>",
2838	  "Display exception frame", 0,
2839	  KDB_ENABLE_MEM_READ);
2840	kdb_register_flags("bt", kdb_bt, "[<vaddr>]",
2841	  "Stack traceback", 1,
2842	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2843	kdb_register_flags("btp", kdb_bt, "<pid>",
2844	  "Display stack for process <pid>", 0,
2845	  KDB_ENABLE_INSPECT);
2846	kdb_register_flags("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
2847	  "Backtrace all processes matching state flag", 0,
2848	  KDB_ENABLE_INSPECT);
2849	kdb_register_flags("btc", kdb_bt, "",
2850	  "Backtrace current process on each cpu", 0,
2851	  KDB_ENABLE_INSPECT);
2852	kdb_register_flags("btt", kdb_bt, "<vaddr>",
2853	  "Backtrace process given its struct task address", 0,
2854	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2855	kdb_register_flags("env", kdb_env, "",
2856	  "Show environment variables", 0,
2857	  KDB_ENABLE_ALWAYS_SAFE);
2858	kdb_register_flags("set", kdb_set, "",
2859	  "Set environment variables", 0,
2860	  KDB_ENABLE_ALWAYS_SAFE);
2861	kdb_register_flags("help", kdb_help, "",
2862	  "Display Help Message", 1,
2863	  KDB_ENABLE_ALWAYS_SAFE);
2864	kdb_register_flags("?", kdb_help, "",
2865	  "Display Help Message", 0,
2866	  KDB_ENABLE_ALWAYS_SAFE);
2867	kdb_register_flags("cpu", kdb_cpu, "<cpunum>",
2868	  "Switch to new cpu", 0,
2869	  KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2870	kdb_register_flags("kgdb", kdb_kgdb, "",
2871	  "Enter kgdb mode", 0, 0);
2872	kdb_register_flags("ps", kdb_ps, "[<flags>|A]",
2873	  "Display active task list", 0,
2874	  KDB_ENABLE_INSPECT);
2875	kdb_register_flags("pid", kdb_pid, "<pidnum>",
2876	  "Switch to another task", 0,
2877	  KDB_ENABLE_INSPECT);
2878	kdb_register_flags("reboot", kdb_reboot, "",
2879	  "Reboot the machine immediately", 0,
2880	  KDB_ENABLE_REBOOT);
2881#if defined(CONFIG_MODULES)
2882	kdb_register_flags("lsmod", kdb_lsmod, "",
2883	  "List loaded kernel modules", 0,
2884	  KDB_ENABLE_INSPECT);
2885#endif
2886#if defined(CONFIG_MAGIC_SYSRQ)
2887	kdb_register_flags("sr", kdb_sr, "<key>",
2888	  "Magic SysRq key", 0,
2889	  KDB_ENABLE_ALWAYS_SAFE);
2890#endif
2891#if defined(CONFIG_PRINTK)
2892	kdb_register_flags("dmesg", kdb_dmesg, "[lines]",
2893	  "Display syslog buffer", 0,
2894	  KDB_ENABLE_ALWAYS_SAFE);
2895#endif
2896	if (arch_kgdb_ops.enable_nmi) {
2897		kdb_register_flags("disable_nmi", kdb_disable_nmi, "",
2898		  "Disable NMI entry to KDB", 0,
2899		  KDB_ENABLE_ALWAYS_SAFE);
2900	}
2901	kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2902	  "Define a set of commands, down to endefcmd", 0,
2903	  KDB_ENABLE_ALWAYS_SAFE);
2904	kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
2905	  "Send a signal to a process", 0,
2906	  KDB_ENABLE_SIGNAL);
2907	kdb_register_flags("summary", kdb_summary, "",
2908	  "Summarize the system", 4,
2909	  KDB_ENABLE_ALWAYS_SAFE);
2910	kdb_register_flags("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]",
2911	  "Display per_cpu variables", 3,
2912	  KDB_ENABLE_MEM_READ);
2913	kdb_register_flags("grephelp", kdb_grep_help, "",
2914	  "Display help on | grep", 0,
2915	  KDB_ENABLE_ALWAYS_SAFE);
2916}
2917
2918/* Execute any commands defined in kdb_cmds.  */
2919static void __init kdb_cmd_init(void)
2920{
2921	int i, diag;
2922	for (i = 0; kdb_cmds[i]; ++i) {
2923		diag = kdb_parse(kdb_cmds[i]);
2924		if (diag)
2925			kdb_printf("kdb command %s failed, kdb diag %d\n",
2926				kdb_cmds[i], diag);
2927	}
2928	if (defcmd_in_progress) {
2929		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2930		kdb_parse("endefcmd");
2931	}
2932}
2933
2934/* Initialize kdb_printf, breakpoint tables and kdb state */
2935void __init kdb_init(int lvl)
2936{
2937	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2938	int i;
2939
2940	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2941		return;
2942	for (i = kdb_init_lvl; i < lvl; i++) {
2943		switch (i) {
2944		case KDB_NOT_INITIALIZED:
2945			kdb_inittab();		/* Initialize Command Table */
2946			kdb_initbptab();	/* Initialize Breakpoints */
2947			break;
2948		case KDB_INIT_EARLY:
2949			kdb_cmd_init();		/* Build kdb_cmds tables */
2950			break;
2951		}
2952	}
2953	kdb_init_lvl = lvl;
2954}