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v5.4
   1/*
   2 * Kernel Debugger Architecture Independent Main Code
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
   9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
  10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
  11 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
  12 */
  13
  14#include <linux/ctype.h>
  15#include <linux/types.h>
  16#include <linux/string.h>
  17#include <linux/kernel.h>
  18#include <linux/kmsg_dump.h>
  19#include <linux/reboot.h>
  20#include <linux/sched.h>
  21#include <linux/sched/loadavg.h>
  22#include <linux/sched/stat.h>
  23#include <linux/sched/debug.h>
  24#include <linux/sysrq.h>
  25#include <linux/smp.h>
  26#include <linux/utsname.h>
  27#include <linux/vmalloc.h>
  28#include <linux/atomic.h>
  29#include <linux/module.h>
  30#include <linux/moduleparam.h>
  31#include <linux/mm.h>
  32#include <linux/init.h>
  33#include <linux/kallsyms.h>
  34#include <linux/kgdb.h>
  35#include <linux/kdb.h>
 
  36#include <linux/notifier.h>
  37#include <linux/interrupt.h>
  38#include <linux/delay.h>
  39#include <linux/nmi.h>
  40#include <linux/time.h>
  41#include <linux/ptrace.h>
  42#include <linux/sysctl.h>
  43#include <linux/cpu.h>
  44#include <linux/kdebug.h>
  45#include <linux/proc_fs.h>
  46#include <linux/uaccess.h>
  47#include <linux/slab.h>
  48#include "kdb_private.h"
  49
  50#undef	MODULE_PARAM_PREFIX
  51#define	MODULE_PARAM_PREFIX "kdb."
  52
  53static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  54module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  55
  56char kdb_grep_string[KDB_GREP_STRLEN];
  57int kdb_grepping_flag;
  58EXPORT_SYMBOL(kdb_grepping_flag);
  59int kdb_grep_leading;
  60int kdb_grep_trailing;
  61
  62/*
  63 * Kernel debugger state flags
  64 */
  65int kdb_flags;
  66
  67/*
  68 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  69 * single thread processors through the kernel debugger.
  70 */
  71int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  72int kdb_nextline = 1;
  73int kdb_state;			/* General KDB state */
  74
  75struct task_struct *kdb_current_task;
  76EXPORT_SYMBOL(kdb_current_task);
  77struct pt_regs *kdb_current_regs;
  78
  79const char *kdb_diemsg;
  80static int kdb_go_count;
  81#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
  82static unsigned int kdb_continue_catastrophic =
  83	CONFIG_KDB_CONTINUE_CATASTROPHIC;
  84#else
  85static unsigned int kdb_continue_catastrophic;
  86#endif
  87
  88/* kdb_commands describes the available commands. */
  89static kdbtab_t *kdb_commands;
  90#define KDB_BASE_CMD_MAX 50
  91static int kdb_max_commands = KDB_BASE_CMD_MAX;
  92static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX];
  93#define for_each_kdbcmd(cmd, num)					\
  94	for ((cmd) = kdb_base_commands, (num) = 0;			\
  95	     num < kdb_max_commands;					\
  96	     num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++)
  97
  98typedef struct _kdbmsg {
  99	int	km_diag;	/* kdb diagnostic */
 100	char	*km_msg;	/* Corresponding message text */
 101} kdbmsg_t;
 102
 103#define KDBMSG(msgnum, text) \
 104	{ KDB_##msgnum, text }
 105
 106static kdbmsg_t kdbmsgs[] = {
 107	KDBMSG(NOTFOUND, "Command Not Found"),
 108	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 109	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 110	       "8 is only allowed on 64 bit systems"),
 111	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 112	KDBMSG(NOTENV, "Cannot find environment variable"),
 113	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 114	KDBMSG(NOTIMP, "Command not implemented"),
 115	KDBMSG(ENVFULL, "Environment full"),
 116	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 117	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 118#ifdef CONFIG_CPU_XSCALE
 119	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 120#else
 121	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 122#endif
 123	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 124	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 125	KDBMSG(BADMODE, "Invalid IDMODE"),
 126	KDBMSG(BADINT, "Illegal numeric value"),
 127	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 128	KDBMSG(BADREG, "Invalid register name"),
 129	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 130	KDBMSG(BADLENGTH, "Invalid length field"),
 131	KDBMSG(NOBP, "No Breakpoint exists"),
 132	KDBMSG(BADADDR, "Invalid address"),
 133	KDBMSG(NOPERM, "Permission denied"),
 134};
 135#undef KDBMSG
 136
 137static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 138
 139
 140/*
 141 * Initial environment.   This is all kept static and local to
 142 * this file.   We don't want to rely on the memory allocation
 143 * mechanisms in the kernel, so we use a very limited allocate-only
 144 * heap for new and altered environment variables.  The entire
 145 * environment is limited to a fixed number of entries (add more
 146 * to __env[] if required) and a fixed amount of heap (add more to
 147 * KDB_ENVBUFSIZE if required).
 148 */
 149
 150static char *__env[] = {
 151#if defined(CONFIG_SMP)
 152 "PROMPT=[%d]kdb> ",
 153#else
 154 "PROMPT=kdb> ",
 155#endif
 156 "MOREPROMPT=more> ",
 157 "RADIX=16",
 158 "MDCOUNT=8",			/* lines of md output */
 159 KDB_PLATFORM_ENV,
 160 "DTABCOUNT=30",
 161 "NOSECT=1",
 162 (char *)0,
 163 (char *)0,
 164 (char *)0,
 165 (char *)0,
 166 (char *)0,
 167 (char *)0,
 168 (char *)0,
 169 (char *)0,
 170 (char *)0,
 171 (char *)0,
 172 (char *)0,
 173 (char *)0,
 174 (char *)0,
 175 (char *)0,
 176 (char *)0,
 177 (char *)0,
 178 (char *)0,
 179 (char *)0,
 180 (char *)0,
 181 (char *)0,
 182 (char *)0,
 183 (char *)0,
 184 (char *)0,
 185 (char *)0,
 186};
 187
 188static const int __nenv = ARRAY_SIZE(__env);
 189
 190struct task_struct *kdb_curr_task(int cpu)
 191{
 192	struct task_struct *p = curr_task(cpu);
 193#ifdef	_TIF_MCA_INIT
 194	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 195		p = krp->p;
 196#endif
 197	return p;
 198}
 199
 200/*
 201 * Check whether the flags of the current command and the permissions
 202 * of the kdb console has allow a command to be run.
 203 */
 204static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 205				   bool no_args)
 206{
 207	/* permissions comes from userspace so needs massaging slightly */
 208	permissions &= KDB_ENABLE_MASK;
 209	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 210
 211	/* some commands change group when launched with no arguments */
 212	if (no_args)
 213		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 214
 215	flags |= KDB_ENABLE_ALL;
 216
 217	return permissions & flags;
 218}
 219
 220/*
 221 * kdbgetenv - This function will return the character string value of
 222 *	an environment variable.
 223 * Parameters:
 224 *	match	A character string representing an environment variable.
 225 * Returns:
 226 *	NULL	No environment variable matches 'match'
 227 *	char*	Pointer to string value of environment variable.
 228 */
 229char *kdbgetenv(const char *match)
 230{
 231	char **ep = __env;
 232	int matchlen = strlen(match);
 233	int i;
 234
 235	for (i = 0; i < __nenv; i++) {
 236		char *e = *ep++;
 237
 238		if (!e)
 239			continue;
 240
 241		if ((strncmp(match, e, matchlen) == 0)
 242		 && ((e[matchlen] == '\0')
 243		   || (e[matchlen] == '='))) {
 244			char *cp = strchr(e, '=');
 245			return cp ? ++cp : "";
 246		}
 247	}
 248	return NULL;
 249}
 250
 251/*
 252 * kdballocenv - This function is used to allocate bytes for
 253 *	environment entries.
 254 * Parameters:
 255 *	match	A character string representing a numeric value
 256 * Outputs:
 257 *	*value  the unsigned long representation of the env variable 'match'
 258 * Returns:
 259 *	Zero on success, a kdb diagnostic on failure.
 260 * Remarks:
 261 *	We use a static environment buffer (envbuffer) to hold the values
 262 *	of dynamically generated environment variables (see kdb_set).  Buffer
 263 *	space once allocated is never free'd, so over time, the amount of space
 264 *	(currently 512 bytes) will be exhausted if env variables are changed
 265 *	frequently.
 266 */
 267static char *kdballocenv(size_t bytes)
 268{
 269#define	KDB_ENVBUFSIZE	512
 270	static char envbuffer[KDB_ENVBUFSIZE];
 271	static int envbufsize;
 272	char *ep = NULL;
 273
 274	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 275		ep = &envbuffer[envbufsize];
 276		envbufsize += bytes;
 277	}
 278	return ep;
 279}
 280
 281/*
 282 * kdbgetulenv - This function will return the value of an unsigned
 283 *	long-valued environment variable.
 284 * Parameters:
 285 *	match	A character string representing a numeric value
 286 * Outputs:
 287 *	*value  the unsigned long represntation of the env variable 'match'
 288 * Returns:
 289 *	Zero on success, a kdb diagnostic on failure.
 290 */
 291static int kdbgetulenv(const char *match, unsigned long *value)
 292{
 293	char *ep;
 294
 295	ep = kdbgetenv(match);
 296	if (!ep)
 297		return KDB_NOTENV;
 298	if (strlen(ep) == 0)
 299		return KDB_NOENVVALUE;
 300
 301	*value = simple_strtoul(ep, NULL, 0);
 302
 303	return 0;
 304}
 305
 306/*
 307 * kdbgetintenv - This function will return the value of an
 308 *	integer-valued environment variable.
 309 * Parameters:
 310 *	match	A character string representing an integer-valued env variable
 311 * Outputs:
 312 *	*value  the integer representation of the environment variable 'match'
 313 * Returns:
 314 *	Zero on success, a kdb diagnostic on failure.
 315 */
 316int kdbgetintenv(const char *match, int *value)
 317{
 318	unsigned long val;
 319	int diag;
 320
 321	diag = kdbgetulenv(match, &val);
 322	if (!diag)
 323		*value = (int) val;
 324	return diag;
 325}
 326
 327/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 328 * kdbgetularg - This function will convert a numeric string into an
 329 *	unsigned long value.
 330 * Parameters:
 331 *	arg	A character string representing a numeric value
 332 * Outputs:
 333 *	*value  the unsigned long represntation of arg.
 334 * Returns:
 335 *	Zero on success, a kdb diagnostic on failure.
 336 */
 337int kdbgetularg(const char *arg, unsigned long *value)
 338{
 339	char *endp;
 340	unsigned long val;
 341
 342	val = simple_strtoul(arg, &endp, 0);
 343
 344	if (endp == arg) {
 345		/*
 346		 * Also try base 16, for us folks too lazy to type the
 347		 * leading 0x...
 348		 */
 349		val = simple_strtoul(arg, &endp, 16);
 350		if (endp == arg)
 351			return KDB_BADINT;
 352	}
 353
 354	*value = val;
 355
 356	return 0;
 357}
 358
 359int kdbgetu64arg(const char *arg, u64 *value)
 360{
 361	char *endp;
 362	u64 val;
 363
 364	val = simple_strtoull(arg, &endp, 0);
 365
 366	if (endp == arg) {
 367
 368		val = simple_strtoull(arg, &endp, 16);
 369		if (endp == arg)
 370			return KDB_BADINT;
 371	}
 372
 373	*value = val;
 374
 375	return 0;
 376}
 377
 378/*
 379 * kdb_set - This function implements the 'set' command.  Alter an
 380 *	existing environment variable or create a new one.
 381 */
 382int kdb_set(int argc, const char **argv)
 383{
 384	int i;
 385	char *ep;
 386	size_t varlen, vallen;
 387
 388	/*
 389	 * we can be invoked two ways:
 390	 *   set var=value    argv[1]="var", argv[2]="value"
 391	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 392	 * - if the latter, shift 'em down.
 393	 */
 394	if (argc == 3) {
 395		argv[2] = argv[3];
 396		argc--;
 397	}
 398
 399	if (argc != 2)
 400		return KDB_ARGCOUNT;
 401
 402	/*
 
 
 
 
 
 
 
 403	 * Check for internal variables
 404	 */
 405	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 406		unsigned int debugflags;
 407		char *cp;
 408
 409		debugflags = simple_strtoul(argv[2], &cp, 0);
 410		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 411			kdb_printf("kdb: illegal debug flags '%s'\n",
 412				    argv[2]);
 413			return 0;
 414		}
 415		kdb_flags = (kdb_flags &
 416			     ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
 417			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 418
 419		return 0;
 420	}
 421
 422	/*
 423	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 424	 * name, argv[2] = value.
 425	 */
 426	varlen = strlen(argv[1]);
 427	vallen = strlen(argv[2]);
 428	ep = kdballocenv(varlen + vallen + 2);
 429	if (ep == (char *)0)
 430		return KDB_ENVBUFFULL;
 431
 432	sprintf(ep, "%s=%s", argv[1], argv[2]);
 433
 434	ep[varlen+vallen+1] = '\0';
 435
 436	for (i = 0; i < __nenv; i++) {
 437		if (__env[i]
 438		 && ((strncmp(__env[i], argv[1], varlen) == 0)
 439		   && ((__env[i][varlen] == '\0')
 440		    || (__env[i][varlen] == '=')))) {
 441			__env[i] = ep;
 442			return 0;
 443		}
 444	}
 445
 446	/*
 447	 * Wasn't existing variable.  Fit into slot.
 448	 */
 449	for (i = 0; i < __nenv-1; i++) {
 450		if (__env[i] == (char *)0) {
 451			__env[i] = ep;
 452			return 0;
 453		}
 454	}
 455
 456	return KDB_ENVFULL;
 457}
 458
 459static int kdb_check_regs(void)
 460{
 461	if (!kdb_current_regs) {
 462		kdb_printf("No current kdb registers."
 463			   "  You may need to select another task\n");
 464		return KDB_BADREG;
 465	}
 466	return 0;
 467}
 468
 469/*
 470 * kdbgetaddrarg - This function is responsible for parsing an
 471 *	address-expression and returning the value of the expression,
 472 *	symbol name, and offset to the caller.
 473 *
 474 *	The argument may consist of a numeric value (decimal or
 475 *	hexidecimal), a symbol name, a register name (preceded by the
 476 *	percent sign), an environment variable with a numeric value
 477 *	(preceded by a dollar sign) or a simple arithmetic expression
 478 *	consisting of a symbol name, +/-, and a numeric constant value
 479 *	(offset).
 480 * Parameters:
 481 *	argc	- count of arguments in argv
 482 *	argv	- argument vector
 483 *	*nextarg - index to next unparsed argument in argv[]
 484 *	regs	- Register state at time of KDB entry
 485 * Outputs:
 486 *	*value	- receives the value of the address-expression
 487 *	*offset - receives the offset specified, if any
 488 *	*name   - receives the symbol name, if any
 489 *	*nextarg - index to next unparsed argument in argv[]
 490 * Returns:
 491 *	zero is returned on success, a kdb diagnostic code is
 492 *      returned on error.
 493 */
 494int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 495		  unsigned long *value,  long *offset,
 496		  char **name)
 497{
 498	unsigned long addr;
 499	unsigned long off = 0;
 500	int positive;
 501	int diag;
 502	int found = 0;
 503	char *symname;
 504	char symbol = '\0';
 505	char *cp;
 506	kdb_symtab_t symtab;
 507
 508	/*
 509	 * If the enable flags prohibit both arbitrary memory access
 510	 * and flow control then there are no reasonable grounds to
 511	 * provide symbol lookup.
 512	 */
 513	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 514			     kdb_cmd_enabled, false))
 515		return KDB_NOPERM;
 516
 517	/*
 518	 * Process arguments which follow the following syntax:
 519	 *
 520	 *  symbol | numeric-address [+/- numeric-offset]
 521	 *  %register
 522	 *  $environment-variable
 523	 */
 524
 525	if (*nextarg > argc)
 526		return KDB_ARGCOUNT;
 527
 528	symname = (char *)argv[*nextarg];
 529
 530	/*
 531	 * If there is no whitespace between the symbol
 532	 * or address and the '+' or '-' symbols, we
 533	 * remember the character and replace it with a
 534	 * null so the symbol/value can be properly parsed
 535	 */
 536	cp = strpbrk(symname, "+-");
 537	if (cp != NULL) {
 538		symbol = *cp;
 539		*cp++ = '\0';
 540	}
 541
 542	if (symname[0] == '$') {
 543		diag = kdbgetulenv(&symname[1], &addr);
 544		if (diag)
 545			return diag;
 546	} else if (symname[0] == '%') {
 547		diag = kdb_check_regs();
 548		if (diag)
 549			return diag;
 550		/* Implement register values with % at a later time as it is
 551		 * arch optional.
 552		 */
 553		return KDB_NOTIMP;
 554	} else {
 555		found = kdbgetsymval(symname, &symtab);
 556		if (found) {
 557			addr = symtab.sym_start;
 558		} else {
 559			diag = kdbgetularg(argv[*nextarg], &addr);
 560			if (diag)
 561				return diag;
 562		}
 563	}
 564
 565	if (!found)
 566		found = kdbnearsym(addr, &symtab);
 567
 568	(*nextarg)++;
 569
 570	if (name)
 571		*name = symname;
 572	if (value)
 573		*value = addr;
 574	if (offset && name && *name)
 575		*offset = addr - symtab.sym_start;
 576
 577	if ((*nextarg > argc)
 578	 && (symbol == '\0'))
 579		return 0;
 580
 581	/*
 582	 * check for +/- and offset
 583	 */
 584
 585	if (symbol == '\0') {
 586		if ((argv[*nextarg][0] != '+')
 587		 && (argv[*nextarg][0] != '-')) {
 588			/*
 589			 * Not our argument.  Return.
 590			 */
 591			return 0;
 592		} else {
 593			positive = (argv[*nextarg][0] == '+');
 594			(*nextarg)++;
 595		}
 596	} else
 597		positive = (symbol == '+');
 598
 599	/*
 600	 * Now there must be an offset!
 601	 */
 602	if ((*nextarg > argc)
 603	 && (symbol == '\0')) {
 604		return KDB_INVADDRFMT;
 605	}
 606
 607	if (!symbol) {
 608		cp = (char *)argv[*nextarg];
 609		(*nextarg)++;
 610	}
 611
 612	diag = kdbgetularg(cp, &off);
 613	if (diag)
 614		return diag;
 615
 616	if (!positive)
 617		off = -off;
 618
 619	if (offset)
 620		*offset += off;
 621
 622	if (value)
 623		*value += off;
 624
 625	return 0;
 626}
 627
 628static void kdb_cmderror(int diag)
 629{
 630	int i;
 631
 632	if (diag >= 0) {
 633		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 634		return;
 635	}
 636
 637	for (i = 0; i < __nkdb_err; i++) {
 638		if (kdbmsgs[i].km_diag == diag) {
 639			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 640			return;
 641		}
 642	}
 643
 644	kdb_printf("Unknown diag %d\n", -diag);
 645}
 646
 647/*
 648 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 649 *	command which defines one command as a set of other commands,
 650 *	terminated by endefcmd.  kdb_defcmd processes the initial
 651 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 652 *	the following commands until 'endefcmd'.
 653 * Inputs:
 654 *	argc	argument count
 655 *	argv	argument vector
 656 * Returns:
 657 *	zero for success, a kdb diagnostic if error
 658 */
 659struct defcmd_set {
 660	int count;
 661	bool usable;
 662	char *name;
 663	char *usage;
 664	char *help;
 665	char **command;
 666};
 667static struct defcmd_set *defcmd_set;
 668static int defcmd_set_count;
 669static bool defcmd_in_progress;
 670
 671/* Forward references */
 672static int kdb_exec_defcmd(int argc, const char **argv);
 673
 674static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 675{
 676	struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
 677	char **save_command = s->command;
 678	if (strcmp(argv0, "endefcmd") == 0) {
 679		defcmd_in_progress = false;
 680		if (!s->count)
 681			s->usable = false;
 682		if (s->usable)
 683			/* macros are always safe because when executed each
 684			 * internal command re-enters kdb_parse() and is
 685			 * safety checked individually.
 686			 */
 687			kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
 688					   s->help, 0,
 689					   KDB_ENABLE_ALWAYS_SAFE);
 690		return 0;
 691	}
 692	if (!s->usable)
 693		return KDB_NOTIMP;
 694	s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);
 695	if (!s->command) {
 696		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
 697			   cmdstr);
 698		s->usable = false;
 699		return KDB_NOTIMP;
 700	}
 701	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
 702	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
 703	kfree(save_command);
 704	return 0;
 705}
 706
 707static int kdb_defcmd(int argc, const char **argv)
 708{
 709	struct defcmd_set *save_defcmd_set = defcmd_set, *s;
 710	if (defcmd_in_progress) {
 711		kdb_printf("kdb: nested defcmd detected, assuming missing "
 712			   "endefcmd\n");
 713		kdb_defcmd2("endefcmd", "endefcmd");
 714	}
 715	if (argc == 0) {
 716		int i;
 717		for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
 718			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
 719				   s->usage, s->help);
 720			for (i = 0; i < s->count; ++i)
 721				kdb_printf("%s", s->command[i]);
 722			kdb_printf("endefcmd\n");
 723		}
 724		return 0;
 725	}
 726	if (argc != 3)
 727		return KDB_ARGCOUNT;
 728	if (in_dbg_master()) {
 729		kdb_printf("Command only available during kdb_init()\n");
 730		return KDB_NOTIMP;
 731	}
 732	defcmd_set = kmalloc_array(defcmd_set_count + 1, sizeof(*defcmd_set),
 733				   GFP_KDB);
 734	if (!defcmd_set)
 735		goto fail_defcmd;
 736	memcpy(defcmd_set, save_defcmd_set,
 737	       defcmd_set_count * sizeof(*defcmd_set));
 738	s = defcmd_set + defcmd_set_count;
 739	memset(s, 0, sizeof(*s));
 740	s->usable = true;
 741	s->name = kdb_strdup(argv[1], GFP_KDB);
 742	if (!s->name)
 743		goto fail_name;
 744	s->usage = kdb_strdup(argv[2], GFP_KDB);
 745	if (!s->usage)
 746		goto fail_usage;
 747	s->help = kdb_strdup(argv[3], GFP_KDB);
 748	if (!s->help)
 749		goto fail_help;
 750	if (s->usage[0] == '"') {
 751		strcpy(s->usage, argv[2]+1);
 752		s->usage[strlen(s->usage)-1] = '\0';
 753	}
 754	if (s->help[0] == '"') {
 755		strcpy(s->help, argv[3]+1);
 756		s->help[strlen(s->help)-1] = '\0';
 757	}
 758	++defcmd_set_count;
 759	defcmd_in_progress = true;
 760	kfree(save_defcmd_set);
 761	return 0;
 762fail_help:
 763	kfree(s->usage);
 764fail_usage:
 765	kfree(s->name);
 766fail_name:
 767	kfree(defcmd_set);
 768fail_defcmd:
 769	kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
 770	defcmd_set = save_defcmd_set;
 771	return KDB_NOTIMP;
 772}
 773
 774/*
 775 * kdb_exec_defcmd - Execute the set of commands associated with this
 776 *	defcmd name.
 777 * Inputs:
 778 *	argc	argument count
 779 *	argv	argument vector
 780 * Returns:
 781 *	zero for success, a kdb diagnostic if error
 782 */
 783static int kdb_exec_defcmd(int argc, const char **argv)
 784{
 785	int i, ret;
 786	struct defcmd_set *s;
 787	if (argc != 0)
 788		return KDB_ARGCOUNT;
 789	for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
 790		if (strcmp(s->name, argv[0]) == 0)
 791			break;
 792	}
 793	if (i == defcmd_set_count) {
 794		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 795			   argv[0]);
 796		return KDB_NOTIMP;
 797	}
 798	for (i = 0; i < s->count; ++i) {
 799		/* Recursive use of kdb_parse, do not use argv after
 800		 * this point */
 801		argv = NULL;
 802		kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
 803		ret = kdb_parse(s->command[i]);
 804		if (ret)
 805			return ret;
 806	}
 807	return 0;
 808}
 809
 810/* Command history */
 811#define KDB_CMD_HISTORY_COUNT	32
 812#define CMD_BUFLEN		200	/* kdb_printf: max printline
 813					 * size == 256 */
 814static unsigned int cmd_head, cmd_tail;
 815static unsigned int cmdptr;
 816static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 817static char cmd_cur[CMD_BUFLEN];
 818
 819/*
 820 * The "str" argument may point to something like  | grep xyz
 821 */
 822static void parse_grep(const char *str)
 823{
 824	int	len;
 825	char	*cp = (char *)str, *cp2;
 826
 827	/* sanity check: we should have been called with the \ first */
 828	if (*cp != '|')
 829		return;
 830	cp++;
 831	while (isspace(*cp))
 832		cp++;
 833	if (!str_has_prefix(cp, "grep ")) {
 834		kdb_printf("invalid 'pipe', see grephelp\n");
 835		return;
 836	}
 837	cp += 5;
 838	while (isspace(*cp))
 839		cp++;
 840	cp2 = strchr(cp, '\n');
 841	if (cp2)
 842		*cp2 = '\0'; /* remove the trailing newline */
 843	len = strlen(cp);
 844	if (len == 0) {
 845		kdb_printf("invalid 'pipe', see grephelp\n");
 846		return;
 847	}
 848	/* now cp points to a nonzero length search string */
 849	if (*cp == '"') {
 850		/* allow it be "x y z" by removing the "'s - there must
 851		   be two of them */
 852		cp++;
 853		cp2 = strchr(cp, '"');
 854		if (!cp2) {
 855			kdb_printf("invalid quoted string, see grephelp\n");
 856			return;
 857		}
 858		*cp2 = '\0'; /* end the string where the 2nd " was */
 859	}
 860	kdb_grep_leading = 0;
 861	if (*cp == '^') {
 862		kdb_grep_leading = 1;
 863		cp++;
 864	}
 865	len = strlen(cp);
 866	kdb_grep_trailing = 0;
 867	if (*(cp+len-1) == '$') {
 868		kdb_grep_trailing = 1;
 869		*(cp+len-1) = '\0';
 870	}
 871	len = strlen(cp);
 872	if (!len)
 873		return;
 874	if (len >= KDB_GREP_STRLEN) {
 875		kdb_printf("search string too long\n");
 876		return;
 877	}
 878	strcpy(kdb_grep_string, cp);
 879	kdb_grepping_flag++;
 880	return;
 881}
 882
 883/*
 884 * kdb_parse - Parse the command line, search the command table for a
 885 *	matching command and invoke the command function.  This
 886 *	function may be called recursively, if it is, the second call
 887 *	will overwrite argv and cbuf.  It is the caller's
 888 *	responsibility to save their argv if they recursively call
 889 *	kdb_parse().
 890 * Parameters:
 891 *      cmdstr	The input command line to be parsed.
 892 *	regs	The registers at the time kdb was entered.
 893 * Returns:
 894 *	Zero for success, a kdb diagnostic if failure.
 895 * Remarks:
 896 *	Limited to 20 tokens.
 897 *
 898 *	Real rudimentary tokenization. Basically only whitespace
 899 *	is considered a token delimeter (but special consideration
 900 *	is taken of the '=' sign as used by the 'set' command).
 901 *
 902 *	The algorithm used to tokenize the input string relies on
 903 *	there being at least one whitespace (or otherwise useless)
 904 *	character between tokens as the character immediately following
 905 *	the token is altered in-place to a null-byte to terminate the
 906 *	token string.
 907 */
 908
 909#define MAXARGC	20
 910
 911int kdb_parse(const char *cmdstr)
 912{
 913	static char *argv[MAXARGC];
 914	static int argc;
 915	static char cbuf[CMD_BUFLEN+2];
 916	char *cp;
 917	char *cpp, quoted;
 918	kdbtab_t *tp;
 919	int i, escaped, ignore_errors = 0, check_grep = 0;
 920
 921	/*
 922	 * First tokenize the command string.
 923	 */
 924	cp = (char *)cmdstr;
 925
 926	if (KDB_FLAG(CMD_INTERRUPT)) {
 927		/* Previous command was interrupted, newline must not
 928		 * repeat the command */
 929		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 930		KDB_STATE_SET(PAGER);
 931		argc = 0;	/* no repeat */
 932	}
 933
 934	if (*cp != '\n' && *cp != '\0') {
 935		argc = 0;
 936		cpp = cbuf;
 937		while (*cp) {
 938			/* skip whitespace */
 939			while (isspace(*cp))
 940				cp++;
 941			if ((*cp == '\0') || (*cp == '\n') ||
 942			    (*cp == '#' && !defcmd_in_progress))
 943				break;
 944			/* special case: check for | grep pattern */
 945			if (*cp == '|') {
 946				check_grep++;
 947				break;
 948			}
 949			if (cpp >= cbuf + CMD_BUFLEN) {
 950				kdb_printf("kdb_parse: command buffer "
 951					   "overflow, command ignored\n%s\n",
 952					   cmdstr);
 953				return KDB_NOTFOUND;
 954			}
 955			if (argc >= MAXARGC - 1) {
 956				kdb_printf("kdb_parse: too many arguments, "
 957					   "command ignored\n%s\n", cmdstr);
 958				return KDB_NOTFOUND;
 959			}
 960			argv[argc++] = cpp;
 961			escaped = 0;
 962			quoted = '\0';
 963			/* Copy to next unquoted and unescaped
 964			 * whitespace or '=' */
 965			while (*cp && *cp != '\n' &&
 966			       (escaped || quoted || !isspace(*cp))) {
 967				if (cpp >= cbuf + CMD_BUFLEN)
 968					break;
 969				if (escaped) {
 970					escaped = 0;
 971					*cpp++ = *cp++;
 972					continue;
 973				}
 974				if (*cp == '\\') {
 975					escaped = 1;
 976					++cp;
 977					continue;
 978				}
 979				if (*cp == quoted)
 980					quoted = '\0';
 981				else if (*cp == '\'' || *cp == '"')
 982					quoted = *cp;
 983				*cpp = *cp++;
 984				if (*cpp == '=' && !quoted)
 985					break;
 986				++cpp;
 987			}
 988			*cpp++ = '\0';	/* Squash a ws or '=' character */
 989		}
 990	}
 991	if (!argc)
 992		return 0;
 993	if (check_grep)
 994		parse_grep(cp);
 995	if (defcmd_in_progress) {
 996		int result = kdb_defcmd2(cmdstr, argv[0]);
 997		if (!defcmd_in_progress) {
 998			argc = 0;	/* avoid repeat on endefcmd */
 999			*(argv[0]) = '\0';
1000		}
1001		return result;
1002	}
1003	if (argv[0][0] == '-' && argv[0][1] &&
1004	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1005		ignore_errors = 1;
1006		++argv[0];
1007	}
1008
1009	for_each_kdbcmd(tp, i) {
1010		if (tp->cmd_name) {
1011			/*
1012			 * If this command is allowed to be abbreviated,
1013			 * check to see if this is it.
1014			 */
1015
1016			if (tp->cmd_minlen
1017			 && (strlen(argv[0]) <= tp->cmd_minlen)) {
1018				if (strncmp(argv[0],
1019					    tp->cmd_name,
1020					    tp->cmd_minlen) == 0) {
1021					break;
1022				}
1023			}
1024
1025			if (strcmp(argv[0], tp->cmd_name) == 0)
1026				break;
1027		}
1028	}
1029
1030	/*
1031	 * If we don't find a command by this name, see if the first
1032	 * few characters of this match any of the known commands.
1033	 * e.g., md1c20 should match md.
1034	 */
1035	if (i == kdb_max_commands) {
1036		for_each_kdbcmd(tp, i) {
1037			if (tp->cmd_name) {
1038				if (strncmp(argv[0],
1039					    tp->cmd_name,
1040					    strlen(tp->cmd_name)) == 0) {
1041					break;
1042				}
1043			}
1044		}
1045	}
1046
1047	if (i < kdb_max_commands) {
1048		int result;
1049
1050		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1051			return KDB_NOPERM;
1052
1053		KDB_STATE_SET(CMD);
1054		result = (*tp->cmd_func)(argc-1, (const char **)argv);
1055		if (result && ignore_errors && result > KDB_CMD_GO)
1056			result = 0;
1057		KDB_STATE_CLEAR(CMD);
1058
1059		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1060			return result;
1061
1062		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1063		if (argv[argc])
1064			*(argv[argc]) = '\0';
1065		return result;
1066	}
1067
1068	/*
1069	 * If the input with which we were presented does not
1070	 * map to an existing command, attempt to parse it as an
1071	 * address argument and display the result.   Useful for
1072	 * obtaining the address of a variable, or the nearest symbol
1073	 * to an address contained in a register.
1074	 */
1075	{
1076		unsigned long value;
1077		char *name = NULL;
1078		long offset;
1079		int nextarg = 0;
1080
1081		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1082				  &value, &offset, &name)) {
1083			return KDB_NOTFOUND;
1084		}
1085
1086		kdb_printf("%s = ", argv[0]);
1087		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1088		kdb_printf("\n");
1089		return 0;
1090	}
1091}
1092
1093
1094static int handle_ctrl_cmd(char *cmd)
1095{
1096#define CTRL_P	16
1097#define CTRL_N	14
1098
1099	/* initial situation */
1100	if (cmd_head == cmd_tail)
1101		return 0;
1102	switch (*cmd) {
1103	case CTRL_P:
1104		if (cmdptr != cmd_tail)
1105			cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
1106		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
 
1107		return 1;
1108	case CTRL_N:
1109		if (cmdptr != cmd_head)
1110			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1111		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1112		return 1;
1113	}
1114	return 0;
1115}
1116
1117/*
1118 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1119 *	the system immediately, or loop for ever on failure.
1120 */
1121static int kdb_reboot(int argc, const char **argv)
1122{
1123	emergency_restart();
1124	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1125	while (1)
1126		cpu_relax();
1127	/* NOTREACHED */
1128	return 0;
1129}
1130
1131static void kdb_dumpregs(struct pt_regs *regs)
1132{
1133	int old_lvl = console_loglevel;
1134	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1135	kdb_trap_printk++;
1136	show_regs(regs);
1137	kdb_trap_printk--;
1138	kdb_printf("\n");
1139	console_loglevel = old_lvl;
1140}
1141
1142void kdb_set_current_task(struct task_struct *p)
1143{
1144	kdb_current_task = p;
1145
1146	if (kdb_task_has_cpu(p)) {
1147		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1148		return;
1149	}
1150	kdb_current_regs = NULL;
1151}
1152
1153static void drop_newline(char *buf)
1154{
1155	size_t len = strlen(buf);
1156
1157	if (len == 0)
1158		return;
1159	if (*(buf + len - 1) == '\n')
1160		*(buf + len - 1) = '\0';
1161}
1162
1163/*
1164 * kdb_local - The main code for kdb.  This routine is invoked on a
1165 *	specific processor, it is not global.  The main kdb() routine
1166 *	ensures that only one processor at a time is in this routine.
1167 *	This code is called with the real reason code on the first
1168 *	entry to a kdb session, thereafter it is called with reason
1169 *	SWITCH, even if the user goes back to the original cpu.
1170 * Inputs:
1171 *	reason		The reason KDB was invoked
1172 *	error		The hardware-defined error code
1173 *	regs		The exception frame at time of fault/breakpoint.
1174 *	db_result	Result code from the break or debug point.
1175 * Returns:
1176 *	0	KDB was invoked for an event which it wasn't responsible
1177 *	1	KDB handled the event for which it was invoked.
1178 *	KDB_CMD_GO	User typed 'go'.
1179 *	KDB_CMD_CPU	User switched to another cpu.
1180 *	KDB_CMD_SS	Single step.
1181 */
1182static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1183		     kdb_dbtrap_t db_result)
1184{
1185	char *cmdbuf;
1186	int diag;
1187	struct task_struct *kdb_current =
1188		kdb_curr_task(raw_smp_processor_id());
1189
1190	KDB_DEBUG_STATE("kdb_local 1", reason);
1191	kdb_go_count = 0;
1192	if (reason == KDB_REASON_DEBUG) {
1193		/* special case below */
1194	} else {
1195		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1196			   kdb_current, kdb_current ? kdb_current->pid : 0);
1197#if defined(CONFIG_SMP)
1198		kdb_printf("on processor %d ", raw_smp_processor_id());
1199#endif
1200	}
1201
1202	switch (reason) {
1203	case KDB_REASON_DEBUG:
1204	{
1205		/*
1206		 * If re-entering kdb after a single step
1207		 * command, don't print the message.
1208		 */
1209		switch (db_result) {
1210		case KDB_DB_BPT:
1211			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1212				   kdb_current, kdb_current->pid);
1213#if defined(CONFIG_SMP)
1214			kdb_printf("on processor %d ", raw_smp_processor_id());
1215#endif
1216			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1217				   instruction_pointer(regs));
1218			break;
1219		case KDB_DB_SS:
1220			break;
1221		case KDB_DB_SSBPT:
1222			KDB_DEBUG_STATE("kdb_local 4", reason);
1223			return 1;	/* kdba_db_trap did the work */
1224		default:
1225			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1226				   db_result);
1227			break;
1228		}
1229
1230	}
1231		break;
1232	case KDB_REASON_ENTER:
1233		if (KDB_STATE(KEYBOARD))
1234			kdb_printf("due to Keyboard Entry\n");
1235		else
1236			kdb_printf("due to KDB_ENTER()\n");
1237		break;
1238	case KDB_REASON_KEYBOARD:
1239		KDB_STATE_SET(KEYBOARD);
1240		kdb_printf("due to Keyboard Entry\n");
1241		break;
1242	case KDB_REASON_ENTER_SLAVE:
1243		/* drop through, slaves only get released via cpu switch */
1244	case KDB_REASON_SWITCH:
1245		kdb_printf("due to cpu switch\n");
1246		break;
1247	case KDB_REASON_OOPS:
1248		kdb_printf("Oops: %s\n", kdb_diemsg);
1249		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1250			   instruction_pointer(regs));
1251		kdb_dumpregs(regs);
1252		break;
1253	case KDB_REASON_SYSTEM_NMI:
1254		kdb_printf("due to System NonMaskable Interrupt\n");
1255		break;
1256	case KDB_REASON_NMI:
1257		kdb_printf("due to NonMaskable Interrupt @ "
1258			   kdb_machreg_fmt "\n",
1259			   instruction_pointer(regs));
1260		break;
1261	case KDB_REASON_SSTEP:
1262	case KDB_REASON_BREAK:
1263		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1264			   reason == KDB_REASON_BREAK ?
1265			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1266		/*
1267		 * Determine if this breakpoint is one that we
1268		 * are interested in.
1269		 */
1270		if (db_result != KDB_DB_BPT) {
1271			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1272				   db_result);
1273			KDB_DEBUG_STATE("kdb_local 6", reason);
1274			return 0;	/* Not for us, dismiss it */
1275		}
1276		break;
1277	case KDB_REASON_RECURSE:
1278		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1279			   instruction_pointer(regs));
1280		break;
1281	default:
1282		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1283		KDB_DEBUG_STATE("kdb_local 8", reason);
1284		return 0;	/* Not for us, dismiss it */
1285	}
1286
1287	while (1) {
1288		/*
1289		 * Initialize pager context.
1290		 */
1291		kdb_nextline = 1;
1292		KDB_STATE_CLEAR(SUPPRESS);
1293		kdb_grepping_flag = 0;
1294		/* ensure the old search does not leak into '/' commands */
1295		kdb_grep_string[0] = '\0';
1296
1297		cmdbuf = cmd_cur;
1298		*cmdbuf = '\0';
1299		*(cmd_hist[cmd_head]) = '\0';
1300
1301do_full_getstr:
1302#if defined(CONFIG_SMP)
1303		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1304			 raw_smp_processor_id());
1305#else
1306		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
1307#endif
1308		if (defcmd_in_progress)
1309			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1310
1311		/*
1312		 * Fetch command from keyboard
1313		 */
1314		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1315		if (*cmdbuf != '\n') {
1316			if (*cmdbuf < 32) {
1317				if (cmdptr == cmd_head) {
1318					strncpy(cmd_hist[cmd_head], cmd_cur,
1319						CMD_BUFLEN);
1320					*(cmd_hist[cmd_head] +
1321					  strlen(cmd_hist[cmd_head])-1) = '\0';
1322				}
1323				if (!handle_ctrl_cmd(cmdbuf))
1324					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1325				cmdbuf = cmd_cur;
1326				goto do_full_getstr;
1327			} else {
1328				strncpy(cmd_hist[cmd_head], cmd_cur,
1329					CMD_BUFLEN);
1330			}
1331
1332			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1333			if (cmd_head == cmd_tail)
1334				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1335		}
1336
1337		cmdptr = cmd_head;
1338		diag = kdb_parse(cmdbuf);
1339		if (diag == KDB_NOTFOUND) {
1340			drop_newline(cmdbuf);
1341			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1342			diag = 0;
1343		}
1344		if (diag == KDB_CMD_GO
1345		 || diag == KDB_CMD_CPU
1346		 || diag == KDB_CMD_SS
1347		 || diag == KDB_CMD_KGDB)
1348			break;
1349
1350		if (diag)
1351			kdb_cmderror(diag);
1352	}
1353	KDB_DEBUG_STATE("kdb_local 9", diag);
1354	return diag;
1355}
1356
1357
1358/*
1359 * kdb_print_state - Print the state data for the current processor
1360 *	for debugging.
1361 * Inputs:
1362 *	text		Identifies the debug point
1363 *	value		Any integer value to be printed, e.g. reason code.
1364 */
1365void kdb_print_state(const char *text, int value)
1366{
1367	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1368		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1369		   kdb_state);
1370}
1371
1372/*
1373 * kdb_main_loop - After initial setup and assignment of the
1374 *	controlling cpu, all cpus are in this loop.  One cpu is in
1375 *	control and will issue the kdb prompt, the others will spin
1376 *	until 'go' or cpu switch.
1377 *
1378 *	To get a consistent view of the kernel stacks for all
1379 *	processes, this routine is invoked from the main kdb code via
1380 *	an architecture specific routine.  kdba_main_loop is
1381 *	responsible for making the kernel stacks consistent for all
1382 *	processes, there should be no difference between a blocked
1383 *	process and a running process as far as kdb is concerned.
1384 * Inputs:
1385 *	reason		The reason KDB was invoked
1386 *	error		The hardware-defined error code
1387 *	reason2		kdb's current reason code.
1388 *			Initially error but can change
1389 *			according to kdb state.
1390 *	db_result	Result code from break or debug point.
1391 *	regs		The exception frame at time of fault/breakpoint.
1392 *			should always be valid.
1393 * Returns:
1394 *	0	KDB was invoked for an event which it wasn't responsible
1395 *	1	KDB handled the event for which it was invoked.
1396 */
1397int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1398	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1399{
1400	int result = 1;
1401	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1402	while (1) {
1403		/*
1404		 * All processors except the one that is in control
1405		 * will spin here.
1406		 */
1407		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1408		while (KDB_STATE(HOLD_CPU)) {
1409			/* state KDB is turned off by kdb_cpu to see if the
1410			 * other cpus are still live, each cpu in this loop
1411			 * turns it back on.
1412			 */
1413			if (!KDB_STATE(KDB))
1414				KDB_STATE_SET(KDB);
1415		}
1416
1417		KDB_STATE_CLEAR(SUPPRESS);
1418		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1419		if (KDB_STATE(LEAVING))
1420			break;	/* Another cpu said 'go' */
1421		/* Still using kdb, this processor is in control */
1422		result = kdb_local(reason2, error, regs, db_result);
1423		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1424
1425		if (result == KDB_CMD_CPU)
1426			break;
1427
1428		if (result == KDB_CMD_SS) {
1429			KDB_STATE_SET(DOING_SS);
1430			break;
1431		}
1432
1433		if (result == KDB_CMD_KGDB) {
1434			if (!KDB_STATE(DOING_KGDB))
1435				kdb_printf("Entering please attach debugger "
1436					   "or use $D#44+ or $3#33\n");
1437			break;
1438		}
1439		if (result && result != 1 && result != KDB_CMD_GO)
1440			kdb_printf("\nUnexpected kdb_local return code %d\n",
1441				   result);
1442		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1443		break;
1444	}
1445	if (KDB_STATE(DOING_SS))
1446		KDB_STATE_CLEAR(SSBPT);
1447
1448	/* Clean up any keyboard devices before leaving */
1449	kdb_kbd_cleanup_state();
1450
1451	return result;
1452}
1453
1454/*
1455 * kdb_mdr - This function implements the guts of the 'mdr', memory
1456 * read command.
1457 *	mdr  <addr arg>,<byte count>
1458 * Inputs:
1459 *	addr	Start address
1460 *	count	Number of bytes
1461 * Returns:
1462 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1463 */
1464static int kdb_mdr(unsigned long addr, unsigned int count)
1465{
1466	unsigned char c;
1467	while (count--) {
1468		if (kdb_getarea(c, addr))
1469			return 0;
1470		kdb_printf("%02x", c);
1471		addr++;
1472	}
1473	kdb_printf("\n");
1474	return 0;
1475}
1476
1477/*
1478 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1479 *	'md8' 'mdr' and 'mds' commands.
1480 *
1481 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1482 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1483 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1484 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1485 *	mdr  <addr arg>,<byte count>
1486 */
1487static void kdb_md_line(const char *fmtstr, unsigned long addr,
1488			int symbolic, int nosect, int bytesperword,
1489			int num, int repeat, int phys)
1490{
1491	/* print just one line of data */
1492	kdb_symtab_t symtab;
1493	char cbuf[32];
1494	char *c = cbuf;
1495	int i;
1496	int j;
1497	unsigned long word;
1498
1499	memset(cbuf, '\0', sizeof(cbuf));
1500	if (phys)
1501		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1502	else
1503		kdb_printf(kdb_machreg_fmt0 " ", addr);
1504
1505	for (i = 0; i < num && repeat--; i++) {
1506		if (phys) {
1507			if (kdb_getphysword(&word, addr, bytesperword))
1508				break;
1509		} else if (kdb_getword(&word, addr, bytesperword))
1510			break;
1511		kdb_printf(fmtstr, word);
1512		if (symbolic)
1513			kdbnearsym(word, &symtab);
1514		else
1515			memset(&symtab, 0, sizeof(symtab));
1516		if (symtab.sym_name) {
1517			kdb_symbol_print(word, &symtab, 0);
1518			if (!nosect) {
1519				kdb_printf("\n");
1520				kdb_printf("                       %s %s "
1521					   kdb_machreg_fmt " "
1522					   kdb_machreg_fmt " "
1523					   kdb_machreg_fmt, symtab.mod_name,
1524					   symtab.sec_name, symtab.sec_start,
1525					   symtab.sym_start, symtab.sym_end);
1526			}
1527			addr += bytesperword;
1528		} else {
1529			union {
1530				u64 word;
1531				unsigned char c[8];
1532			} wc;
1533			unsigned char *cp;
1534#ifdef	__BIG_ENDIAN
1535			cp = wc.c + 8 - bytesperword;
1536#else
1537			cp = wc.c;
1538#endif
1539			wc.word = word;
1540#define printable_char(c) \
1541	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1542			for (j = 0; j < bytesperword; j++)
1543				*c++ = printable_char(*cp++);
1544			addr += bytesperword;
1545#undef printable_char
1546		}
1547	}
1548	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1549		   " ", cbuf);
1550}
1551
1552static int kdb_md(int argc, const char **argv)
1553{
1554	static unsigned long last_addr;
1555	static int last_radix, last_bytesperword, last_repeat;
1556	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1557	int nosect = 0;
1558	char fmtchar, fmtstr[64];
1559	unsigned long addr;
1560	unsigned long word;
1561	long offset = 0;
1562	int symbolic = 0;
1563	int valid = 0;
1564	int phys = 0;
1565	int raw = 0;
1566
1567	kdbgetintenv("MDCOUNT", &mdcount);
1568	kdbgetintenv("RADIX", &radix);
1569	kdbgetintenv("BYTESPERWORD", &bytesperword);
1570
1571	/* Assume 'md <addr>' and start with environment values */
1572	repeat = mdcount * 16 / bytesperword;
1573
1574	if (strcmp(argv[0], "mdr") == 0) {
1575		if (argc == 2 || (argc == 0 && last_addr != 0))
1576			valid = raw = 1;
1577		else
1578			return KDB_ARGCOUNT;
1579	} else if (isdigit(argv[0][2])) {
1580		bytesperword = (int)(argv[0][2] - '0');
1581		if (bytesperword == 0) {
1582			bytesperword = last_bytesperword;
1583			if (bytesperword == 0)
1584				bytesperword = 4;
1585		}
1586		last_bytesperword = bytesperword;
1587		repeat = mdcount * 16 / bytesperword;
1588		if (!argv[0][3])
1589			valid = 1;
1590		else if (argv[0][3] == 'c' && argv[0][4]) {
1591			char *p;
1592			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1593			mdcount = ((repeat * bytesperword) + 15) / 16;
1594			valid = !*p;
1595		}
1596		last_repeat = repeat;
1597	} else if (strcmp(argv[0], "md") == 0)
1598		valid = 1;
1599	else if (strcmp(argv[0], "mds") == 0)
1600		valid = 1;
1601	else if (strcmp(argv[0], "mdp") == 0) {
1602		phys = valid = 1;
1603	}
1604	if (!valid)
1605		return KDB_NOTFOUND;
1606
1607	if (argc == 0) {
1608		if (last_addr == 0)
1609			return KDB_ARGCOUNT;
1610		addr = last_addr;
1611		radix = last_radix;
1612		bytesperword = last_bytesperword;
1613		repeat = last_repeat;
1614		if (raw)
1615			mdcount = repeat;
1616		else
1617			mdcount = ((repeat * bytesperword) + 15) / 16;
1618	}
1619
1620	if (argc) {
1621		unsigned long val;
1622		int diag, nextarg = 1;
1623		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1624				     &offset, NULL);
1625		if (diag)
1626			return diag;
1627		if (argc > nextarg+2)
1628			return KDB_ARGCOUNT;
1629
1630		if (argc >= nextarg) {
1631			diag = kdbgetularg(argv[nextarg], &val);
1632			if (!diag) {
1633				mdcount = (int) val;
1634				if (raw)
1635					repeat = mdcount;
1636				else
1637					repeat = mdcount * 16 / bytesperword;
1638			}
1639		}
1640		if (argc >= nextarg+1) {
1641			diag = kdbgetularg(argv[nextarg+1], &val);
1642			if (!diag)
1643				radix = (int) val;
1644		}
1645	}
1646
1647	if (strcmp(argv[0], "mdr") == 0) {
1648		int ret;
1649		last_addr = addr;
1650		ret = kdb_mdr(addr, mdcount);
1651		last_addr += mdcount;
1652		last_repeat = mdcount;
1653		last_bytesperword = bytesperword; // to make REPEAT happy
1654		return ret;
1655	}
1656
1657	switch (radix) {
1658	case 10:
1659		fmtchar = 'd';
1660		break;
1661	case 16:
1662		fmtchar = 'x';
1663		break;
1664	case 8:
1665		fmtchar = 'o';
1666		break;
1667	default:
1668		return KDB_BADRADIX;
1669	}
1670
1671	last_radix = radix;
1672
1673	if (bytesperword > KDB_WORD_SIZE)
1674		return KDB_BADWIDTH;
1675
1676	switch (bytesperword) {
1677	case 8:
1678		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1679		break;
1680	case 4:
1681		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1682		break;
1683	case 2:
1684		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1685		break;
1686	case 1:
1687		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1688		break;
1689	default:
1690		return KDB_BADWIDTH;
1691	}
1692
1693	last_repeat = repeat;
1694	last_bytesperword = bytesperword;
1695
1696	if (strcmp(argv[0], "mds") == 0) {
1697		symbolic = 1;
1698		/* Do not save these changes as last_*, they are temporary mds
1699		 * overrides.
1700		 */
1701		bytesperword = KDB_WORD_SIZE;
1702		repeat = mdcount;
1703		kdbgetintenv("NOSECT", &nosect);
1704	}
1705
1706	/* Round address down modulo BYTESPERWORD */
1707
1708	addr &= ~(bytesperword-1);
1709
1710	while (repeat > 0) {
1711		unsigned long a;
1712		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1713
1714		if (KDB_FLAG(CMD_INTERRUPT))
1715			return 0;
1716		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1717			if (phys) {
1718				if (kdb_getphysword(&word, a, bytesperword)
1719						|| word)
1720					break;
1721			} else if (kdb_getword(&word, a, bytesperword) || word)
1722				break;
1723		}
1724		n = min(num, repeat);
1725		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1726			    num, repeat, phys);
1727		addr += bytesperword * n;
1728		repeat -= n;
1729		z = (z + num - 1) / num;
1730		if (z > 2) {
1731			int s = num * (z-2);
1732			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1733				   " zero suppressed\n",
1734				addr, addr + bytesperword * s - 1);
1735			addr += bytesperword * s;
1736			repeat -= s;
1737		}
1738	}
1739	last_addr = addr;
1740
1741	return 0;
1742}
1743
1744/*
1745 * kdb_mm - This function implements the 'mm' command.
1746 *	mm address-expression new-value
1747 * Remarks:
1748 *	mm works on machine words, mmW works on bytes.
1749 */
1750static int kdb_mm(int argc, const char **argv)
1751{
1752	int diag;
1753	unsigned long addr;
1754	long offset = 0;
1755	unsigned long contents;
1756	int nextarg;
1757	int width;
1758
1759	if (argv[0][2] && !isdigit(argv[0][2]))
1760		return KDB_NOTFOUND;
1761
1762	if (argc < 2)
1763		return KDB_ARGCOUNT;
1764
1765	nextarg = 1;
1766	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1767	if (diag)
1768		return diag;
1769
1770	if (nextarg > argc)
1771		return KDB_ARGCOUNT;
1772	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1773	if (diag)
1774		return diag;
1775
1776	if (nextarg != argc + 1)
1777		return KDB_ARGCOUNT;
1778
1779	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1780	diag = kdb_putword(addr, contents, width);
1781	if (diag)
1782		return diag;
1783
1784	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1785
1786	return 0;
1787}
1788
1789/*
1790 * kdb_go - This function implements the 'go' command.
1791 *	go [address-expression]
1792 */
1793static int kdb_go(int argc, const char **argv)
1794{
1795	unsigned long addr;
1796	int diag;
1797	int nextarg;
1798	long offset;
1799
1800	if (raw_smp_processor_id() != kdb_initial_cpu) {
1801		kdb_printf("go must execute on the entry cpu, "
1802			   "please use \"cpu %d\" and then execute go\n",
1803			   kdb_initial_cpu);
1804		return KDB_BADCPUNUM;
1805	}
1806	if (argc == 1) {
1807		nextarg = 1;
1808		diag = kdbgetaddrarg(argc, argv, &nextarg,
1809				     &addr, &offset, NULL);
1810		if (diag)
1811			return diag;
1812	} else if (argc) {
1813		return KDB_ARGCOUNT;
1814	}
1815
1816	diag = KDB_CMD_GO;
1817	if (KDB_FLAG(CATASTROPHIC)) {
1818		kdb_printf("Catastrophic error detected\n");
1819		kdb_printf("kdb_continue_catastrophic=%d, ",
1820			kdb_continue_catastrophic);
1821		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1822			kdb_printf("type go a second time if you really want "
1823				   "to continue\n");
1824			return 0;
1825		}
1826		if (kdb_continue_catastrophic == 2) {
1827			kdb_printf("forcing reboot\n");
1828			kdb_reboot(0, NULL);
1829		}
1830		kdb_printf("attempting to continue\n");
1831	}
1832	return diag;
1833}
1834
1835/*
1836 * kdb_rd - This function implements the 'rd' command.
1837 */
1838static int kdb_rd(int argc, const char **argv)
1839{
1840	int len = kdb_check_regs();
1841#if DBG_MAX_REG_NUM > 0
1842	int i;
1843	char *rname;
1844	int rsize;
1845	u64 reg64;
1846	u32 reg32;
1847	u16 reg16;
1848	u8 reg8;
1849
1850	if (len)
1851		return len;
1852
1853	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1854		rsize = dbg_reg_def[i].size * 2;
1855		if (rsize > 16)
1856			rsize = 2;
1857		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1858			len = 0;
1859			kdb_printf("\n");
1860		}
1861		if (len)
1862			len += kdb_printf("  ");
1863		switch(dbg_reg_def[i].size * 8) {
1864		case 8:
1865			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1866			if (!rname)
1867				break;
1868			len += kdb_printf("%s: %02x", rname, reg8);
1869			break;
1870		case 16:
1871			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1872			if (!rname)
1873				break;
1874			len += kdb_printf("%s: %04x", rname, reg16);
1875			break;
1876		case 32:
1877			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1878			if (!rname)
1879				break;
1880			len += kdb_printf("%s: %08x", rname, reg32);
1881			break;
1882		case 64:
1883			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1884			if (!rname)
1885				break;
1886			len += kdb_printf("%s: %016llx", rname, reg64);
1887			break;
1888		default:
1889			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1890		}
1891	}
1892	kdb_printf("\n");
1893#else
1894	if (len)
1895		return len;
1896
1897	kdb_dumpregs(kdb_current_regs);
1898#endif
1899	return 0;
1900}
1901
1902/*
1903 * kdb_rm - This function implements the 'rm' (register modify)  command.
1904 *	rm register-name new-contents
1905 * Remarks:
1906 *	Allows register modification with the same restrictions as gdb
1907 */
1908static int kdb_rm(int argc, const char **argv)
1909{
1910#if DBG_MAX_REG_NUM > 0
1911	int diag;
1912	const char *rname;
1913	int i;
1914	u64 reg64;
1915	u32 reg32;
1916	u16 reg16;
1917	u8 reg8;
1918
1919	if (argc != 2)
1920		return KDB_ARGCOUNT;
1921	/*
1922	 * Allow presence or absence of leading '%' symbol.
1923	 */
1924	rname = argv[1];
1925	if (*rname == '%')
1926		rname++;
1927
1928	diag = kdbgetu64arg(argv[2], &reg64);
1929	if (diag)
1930		return diag;
1931
1932	diag = kdb_check_regs();
1933	if (diag)
1934		return diag;
1935
1936	diag = KDB_BADREG;
1937	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1938		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1939			diag = 0;
1940			break;
1941		}
1942	}
1943	if (!diag) {
1944		switch(dbg_reg_def[i].size * 8) {
1945		case 8:
1946			reg8 = reg64;
1947			dbg_set_reg(i, &reg8, kdb_current_regs);
1948			break;
1949		case 16:
1950			reg16 = reg64;
1951			dbg_set_reg(i, &reg16, kdb_current_regs);
1952			break;
1953		case 32:
1954			reg32 = reg64;
1955			dbg_set_reg(i, &reg32, kdb_current_regs);
1956			break;
1957		case 64:
1958			dbg_set_reg(i, &reg64, kdb_current_regs);
1959			break;
1960		}
1961	}
1962	return diag;
1963#else
1964	kdb_printf("ERROR: Register set currently not implemented\n");
1965    return 0;
1966#endif
1967}
1968
1969#if defined(CONFIG_MAGIC_SYSRQ)
1970/*
1971 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1972 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1973 *		sr <magic-sysrq-code>
1974 */
1975static int kdb_sr(int argc, const char **argv)
1976{
1977	bool check_mask =
1978	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1979
1980	if (argc != 1)
1981		return KDB_ARGCOUNT;
1982
1983	kdb_trap_printk++;
1984	__handle_sysrq(*argv[1], check_mask);
1985	kdb_trap_printk--;
1986
1987	return 0;
1988}
1989#endif	/* CONFIG_MAGIC_SYSRQ */
1990
1991/*
1992 * kdb_ef - This function implements the 'regs' (display exception
1993 *	frame) command.  This command takes an address and expects to
1994 *	find an exception frame at that address, formats and prints
1995 *	it.
1996 *		regs address-expression
1997 * Remarks:
1998 *	Not done yet.
1999 */
2000static int kdb_ef(int argc, const char **argv)
2001{
2002	int diag;
2003	unsigned long addr;
2004	long offset;
2005	int nextarg;
2006
2007	if (argc != 1)
2008		return KDB_ARGCOUNT;
2009
2010	nextarg = 1;
2011	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2012	if (diag)
2013		return diag;
2014	show_regs((struct pt_regs *)addr);
2015	return 0;
2016}
2017
2018#if defined(CONFIG_MODULES)
2019/*
2020 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2021 *	currently loaded kernel modules.
2022 *	Mostly taken from userland lsmod.
2023 */
2024static int kdb_lsmod(int argc, const char **argv)
2025{
2026	struct module *mod;
2027
2028	if (argc != 0)
2029		return KDB_ARGCOUNT;
2030
2031	kdb_printf("Module                  Size  modstruct     Used by\n");
2032	list_for_each_entry(mod, kdb_modules, list) {
2033		if (mod->state == MODULE_STATE_UNFORMED)
2034			continue;
2035
2036		kdb_printf("%-20s%8u  0x%px ", mod->name,
2037			   mod->core_layout.size, (void *)mod);
2038#ifdef CONFIG_MODULE_UNLOAD
2039		kdb_printf("%4d ", module_refcount(mod));
2040#endif
2041		if (mod->state == MODULE_STATE_GOING)
2042			kdb_printf(" (Unloading)");
2043		else if (mod->state == MODULE_STATE_COMING)
2044			kdb_printf(" (Loading)");
2045		else
2046			kdb_printf(" (Live)");
2047		kdb_printf(" 0x%px", mod->core_layout.base);
2048
2049#ifdef CONFIG_MODULE_UNLOAD
2050		{
2051			struct module_use *use;
2052			kdb_printf(" [ ");
2053			list_for_each_entry(use, &mod->source_list,
2054					    source_list)
2055				kdb_printf("%s ", use->target->name);
2056			kdb_printf("]\n");
2057		}
2058#endif
2059	}
2060
2061	return 0;
2062}
2063
2064#endif	/* CONFIG_MODULES */
2065
2066/*
2067 * kdb_env - This function implements the 'env' command.  Display the
2068 *	current environment variables.
2069 */
2070
2071static int kdb_env(int argc, const char **argv)
2072{
2073	int i;
2074
2075	for (i = 0; i < __nenv; i++) {
2076		if (__env[i])
2077			kdb_printf("%s\n", __env[i]);
2078	}
2079
2080	if (KDB_DEBUG(MASK))
2081		kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
 
2082
2083	return 0;
2084}
2085
2086#ifdef CONFIG_PRINTK
2087/*
2088 * kdb_dmesg - This function implements the 'dmesg' command to display
2089 *	the contents of the syslog buffer.
2090 *		dmesg [lines] [adjust]
2091 */
2092static int kdb_dmesg(int argc, const char **argv)
2093{
2094	int diag;
2095	int logging;
2096	int lines = 0;
2097	int adjust = 0;
2098	int n = 0;
2099	int skip = 0;
2100	struct kmsg_dumper dumper = { .active = 1 };
2101	size_t len;
2102	char buf[201];
2103
2104	if (argc > 2)
2105		return KDB_ARGCOUNT;
2106	if (argc) {
2107		char *cp;
2108		lines = simple_strtol(argv[1], &cp, 0);
2109		if (*cp)
2110			lines = 0;
2111		if (argc > 1) {
2112			adjust = simple_strtoul(argv[2], &cp, 0);
2113			if (*cp || adjust < 0)
2114				adjust = 0;
2115		}
2116	}
2117
2118	/* disable LOGGING if set */
2119	diag = kdbgetintenv("LOGGING", &logging);
2120	if (!diag && logging) {
2121		const char *setargs[] = { "set", "LOGGING", "0" };
2122		kdb_set(2, setargs);
2123	}
2124
2125	kmsg_dump_rewind_nolock(&dumper);
2126	while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
2127		n++;
2128
2129	if (lines < 0) {
2130		if (adjust >= n)
2131			kdb_printf("buffer only contains %d lines, nothing "
2132				   "printed\n", n);
2133		else if (adjust - lines >= n)
2134			kdb_printf("buffer only contains %d lines, last %d "
2135				   "lines printed\n", n, n - adjust);
2136		skip = adjust;
2137		lines = abs(lines);
2138	} else if (lines > 0) {
2139		skip = n - lines - adjust;
2140		lines = abs(lines);
2141		if (adjust >= n) {
2142			kdb_printf("buffer only contains %d lines, "
2143				   "nothing printed\n", n);
2144			skip = n;
2145		} else if (skip < 0) {
2146			lines += skip;
2147			skip = 0;
2148			kdb_printf("buffer only contains %d lines, first "
2149				   "%d lines printed\n", n, lines);
2150		}
2151	} else {
2152		lines = n;
2153	}
2154
2155	if (skip >= n || skip < 0)
2156		return 0;
2157
2158	kmsg_dump_rewind_nolock(&dumper);
2159	while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
2160		if (skip) {
2161			skip--;
2162			continue;
2163		}
2164		if (!lines--)
2165			break;
2166		if (KDB_FLAG(CMD_INTERRUPT))
2167			return 0;
2168
2169		kdb_printf("%.*s\n", (int)len - 1, buf);
2170	}
2171
2172	return 0;
2173}
2174#endif /* CONFIG_PRINTK */
2175
2176/* Make sure we balance enable/disable calls, must disable first. */
2177static atomic_t kdb_nmi_disabled;
2178
2179static int kdb_disable_nmi(int argc, const char *argv[])
2180{
2181	if (atomic_read(&kdb_nmi_disabled))
2182		return 0;
2183	atomic_set(&kdb_nmi_disabled, 1);
2184	arch_kgdb_ops.enable_nmi(0);
2185	return 0;
2186}
2187
2188static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2189{
2190	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2191		return -EINVAL;
2192	arch_kgdb_ops.enable_nmi(1);
2193	return 0;
2194}
2195
2196static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2197	.set = kdb_param_enable_nmi,
2198};
2199module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2200
2201/*
2202 * kdb_cpu - This function implements the 'cpu' command.
2203 *	cpu	[<cpunum>]
2204 * Returns:
2205 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2206 */
2207static void kdb_cpu_status(void)
2208{
2209	int i, start_cpu, first_print = 1;
2210	char state, prev_state = '?';
2211
2212	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2213	kdb_printf("Available cpus: ");
2214	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2215		if (!cpu_online(i)) {
2216			state = 'F';	/* cpu is offline */
2217		} else if (!kgdb_info[i].enter_kgdb) {
2218			state = 'D';	/* cpu is online but unresponsive */
2219		} else {
2220			state = ' ';	/* cpu is responding to kdb */
2221			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2222				state = 'I';	/* idle task */
2223		}
2224		if (state != prev_state) {
2225			if (prev_state != '?') {
2226				if (!first_print)
2227					kdb_printf(", ");
2228				first_print = 0;
2229				kdb_printf("%d", start_cpu);
2230				if (start_cpu < i-1)
2231					kdb_printf("-%d", i-1);
2232				if (prev_state != ' ')
2233					kdb_printf("(%c)", prev_state);
2234			}
2235			prev_state = state;
2236			start_cpu = i;
2237		}
2238	}
2239	/* print the trailing cpus, ignoring them if they are all offline */
2240	if (prev_state != 'F') {
2241		if (!first_print)
2242			kdb_printf(", ");
2243		kdb_printf("%d", start_cpu);
2244		if (start_cpu < i-1)
2245			kdb_printf("-%d", i-1);
2246		if (prev_state != ' ')
2247			kdb_printf("(%c)", prev_state);
2248	}
2249	kdb_printf("\n");
2250}
2251
2252static int kdb_cpu(int argc, const char **argv)
2253{
2254	unsigned long cpunum;
2255	int diag;
2256
2257	if (argc == 0) {
2258		kdb_cpu_status();
2259		return 0;
2260	}
2261
2262	if (argc != 1)
2263		return KDB_ARGCOUNT;
2264
2265	diag = kdbgetularg(argv[1], &cpunum);
2266	if (diag)
2267		return diag;
2268
2269	/*
2270	 * Validate cpunum
2271	 */
2272	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2273		return KDB_BADCPUNUM;
2274
2275	dbg_switch_cpu = cpunum;
2276
2277	/*
2278	 * Switch to other cpu
2279	 */
2280	return KDB_CMD_CPU;
2281}
2282
2283/* The user may not realize that ps/bta with no parameters does not print idle
2284 * or sleeping system daemon processes, so tell them how many were suppressed.
2285 */
2286void kdb_ps_suppressed(void)
2287{
2288	int idle = 0, daemon = 0;
2289	unsigned long mask_I = kdb_task_state_string("I"),
2290		      mask_M = kdb_task_state_string("M");
2291	unsigned long cpu;
2292	const struct task_struct *p, *g;
2293	for_each_online_cpu(cpu) {
2294		p = kdb_curr_task(cpu);
2295		if (kdb_task_state(p, mask_I))
2296			++idle;
2297	}
2298	kdb_do_each_thread(g, p) {
2299		if (kdb_task_state(p, mask_M))
2300			++daemon;
2301	} kdb_while_each_thread(g, p);
2302	if (idle || daemon) {
2303		if (idle)
2304			kdb_printf("%d idle process%s (state I)%s\n",
2305				   idle, idle == 1 ? "" : "es",
2306				   daemon ? " and " : "");
2307		if (daemon)
2308			kdb_printf("%d sleeping system daemon (state M) "
2309				   "process%s", daemon,
2310				   daemon == 1 ? "" : "es");
2311		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2312	}
2313}
2314
2315/*
2316 * kdb_ps - This function implements the 'ps' command which shows a
2317 *	list of the active processes.
2318 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2319 */
2320void kdb_ps1(const struct task_struct *p)
2321{
2322	int cpu;
2323	unsigned long tmp;
2324
2325	if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
 
2326		return;
2327
2328	cpu = kdb_process_cpu(p);
2329	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2330		   (void *)p, p->pid, p->parent->pid,
2331		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2332		   kdb_task_state_char(p),
2333		   (void *)(&p->thread),
2334		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2335		   p->comm);
2336	if (kdb_task_has_cpu(p)) {
2337		if (!KDB_TSK(cpu)) {
2338			kdb_printf("  Error: no saved data for this cpu\n");
2339		} else {
2340			if (KDB_TSK(cpu) != p)
2341				kdb_printf("  Error: does not match running "
2342				   "process table (0x%px)\n", KDB_TSK(cpu));
2343		}
2344	}
2345}
2346
2347static int kdb_ps(int argc, const char **argv)
2348{
2349	struct task_struct *g, *p;
2350	unsigned long mask, cpu;
2351
2352	if (argc == 0)
2353		kdb_ps_suppressed();
2354	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2355		(int)(2*sizeof(void *))+2, "Task Addr",
2356		(int)(2*sizeof(void *))+2, "Thread");
2357	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2358	/* Run the active tasks first */
2359	for_each_online_cpu(cpu) {
2360		if (KDB_FLAG(CMD_INTERRUPT))
2361			return 0;
2362		p = kdb_curr_task(cpu);
2363		if (kdb_task_state(p, mask))
2364			kdb_ps1(p);
2365	}
2366	kdb_printf("\n");
2367	/* Now the real tasks */
2368	kdb_do_each_thread(g, p) {
2369		if (KDB_FLAG(CMD_INTERRUPT))
2370			return 0;
2371		if (kdb_task_state(p, mask))
2372			kdb_ps1(p);
2373	} kdb_while_each_thread(g, p);
2374
2375	return 0;
2376}
2377
2378/*
2379 * kdb_pid - This function implements the 'pid' command which switches
2380 *	the currently active process.
2381 *		pid [<pid> | R]
2382 */
2383static int kdb_pid(int argc, const char **argv)
2384{
2385	struct task_struct *p;
2386	unsigned long val;
2387	int diag;
2388
2389	if (argc > 1)
2390		return KDB_ARGCOUNT;
2391
2392	if (argc) {
2393		if (strcmp(argv[1], "R") == 0) {
2394			p = KDB_TSK(kdb_initial_cpu);
2395		} else {
2396			diag = kdbgetularg(argv[1], &val);
2397			if (diag)
2398				return KDB_BADINT;
2399
2400			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2401			if (!p) {
2402				kdb_printf("No task with pid=%d\n", (pid_t)val);
2403				return 0;
2404			}
2405		}
2406		kdb_set_current_task(p);
2407	}
2408	kdb_printf("KDB current process is %s(pid=%d)\n",
2409		   kdb_current_task->comm,
2410		   kdb_current_task->pid);
2411
2412	return 0;
2413}
2414
2415static int kdb_kgdb(int argc, const char **argv)
2416{
2417	return KDB_CMD_KGDB;
2418}
2419
2420/*
2421 * kdb_help - This function implements the 'help' and '?' commands.
2422 */
2423static int kdb_help(int argc, const char **argv)
2424{
2425	kdbtab_t *kt;
2426	int i;
2427
2428	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2429	kdb_printf("-----------------------------"
2430		   "-----------------------------\n");
2431	for_each_kdbcmd(kt, i) {
2432		char *space = "";
2433		if (KDB_FLAG(CMD_INTERRUPT))
2434			return 0;
2435		if (!kt->cmd_name)
2436			continue;
2437		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2438			continue;
2439		if (strlen(kt->cmd_usage) > 20)
2440			space = "\n                                    ";
2441		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2442			   kt->cmd_usage, space, kt->cmd_help);
2443	}
2444	return 0;
2445}
2446
2447/*
2448 * kdb_kill - This function implements the 'kill' commands.
2449 */
2450static int kdb_kill(int argc, const char **argv)
2451{
2452	long sig, pid;
2453	char *endp;
2454	struct task_struct *p;
2455
2456	if (argc != 2)
2457		return KDB_ARGCOUNT;
2458
2459	sig = simple_strtol(argv[1], &endp, 0);
2460	if (*endp)
2461		return KDB_BADINT;
2462	if ((sig >= 0) || !valid_signal(-sig)) {
2463		kdb_printf("Invalid signal parameter.<-signal>\n");
2464		return 0;
2465	}
2466	sig = -sig;
2467
2468	pid = simple_strtol(argv[2], &endp, 0);
2469	if (*endp)
2470		return KDB_BADINT;
2471	if (pid <= 0) {
2472		kdb_printf("Process ID must be large than 0.\n");
2473		return 0;
2474	}
2475
2476	/* Find the process. */
2477	p = find_task_by_pid_ns(pid, &init_pid_ns);
2478	if (!p) {
2479		kdb_printf("The specified process isn't found.\n");
2480		return 0;
2481	}
2482	p = p->group_leader;
2483	kdb_send_sig(p, sig);
2484	return 0;
2485}
2486
2487/*
2488 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2489 * I cannot call that code directly from kdb, it has an unconditional
2490 * cli()/sti() and calls routines that take locks which can stop the debugger.
2491 */
2492static void kdb_sysinfo(struct sysinfo *val)
2493{
2494	u64 uptime = ktime_get_mono_fast_ns();
2495
2496	memset(val, 0, sizeof(*val));
2497	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2498	val->loads[0] = avenrun[0];
2499	val->loads[1] = avenrun[1];
2500	val->loads[2] = avenrun[2];
2501	val->procs = nr_threads-1;
2502	si_meminfo(val);
2503
2504	return;
2505}
2506
2507/*
2508 * kdb_summary - This function implements the 'summary' command.
2509 */
2510static int kdb_summary(int argc, const char **argv)
2511{
2512	time64_t now;
2513	struct tm tm;
2514	struct sysinfo val;
2515
2516	if (argc)
2517		return KDB_ARGCOUNT;
2518
2519	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2520	kdb_printf("release    %s\n", init_uts_ns.name.release);
2521	kdb_printf("version    %s\n", init_uts_ns.name.version);
2522	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2523	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2524	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2525
2526	now = __ktime_get_real_seconds();
2527	time64_to_tm(now, 0, &tm);
2528	kdb_printf("date       %04ld-%02d-%02d %02d:%02d:%02d "
2529		   "tz_minuteswest %d\n",
2530		1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2531		tm.tm_hour, tm.tm_min, tm.tm_sec,
2532		sys_tz.tz_minuteswest);
2533
2534	kdb_sysinfo(&val);
2535	kdb_printf("uptime     ");
2536	if (val.uptime > (24*60*60)) {
2537		int days = val.uptime / (24*60*60);
2538		val.uptime %= (24*60*60);
2539		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2540	}
2541	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2542
2543	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2544		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2545		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2546		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2547
2548	/* Display in kilobytes */
2549#define K(x) ((x) << (PAGE_SHIFT - 10))
2550	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2551		   "Buffers:        %8lu kB\n",
2552		   K(val.totalram), K(val.freeram), K(val.bufferram));
2553	return 0;
2554}
2555
2556/*
2557 * kdb_per_cpu - This function implements the 'per_cpu' command.
2558 */
2559static int kdb_per_cpu(int argc, const char **argv)
2560{
2561	char fmtstr[64];
2562	int cpu, diag, nextarg = 1;
2563	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2564
2565	if (argc < 1 || argc > 3)
2566		return KDB_ARGCOUNT;
2567
2568	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2569	if (diag)
2570		return diag;
2571
2572	if (argc >= 2) {
2573		diag = kdbgetularg(argv[2], &bytesperword);
2574		if (diag)
2575			return diag;
2576	}
2577	if (!bytesperword)
2578		bytesperword = KDB_WORD_SIZE;
2579	else if (bytesperword > KDB_WORD_SIZE)
2580		return KDB_BADWIDTH;
2581	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2582	if (argc >= 3) {
2583		diag = kdbgetularg(argv[3], &whichcpu);
2584		if (diag)
2585			return diag;
2586		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2587			kdb_printf("cpu %ld is not online\n", whichcpu);
2588			return KDB_BADCPUNUM;
2589		}
2590	}
2591
2592	/* Most architectures use __per_cpu_offset[cpu], some use
2593	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2594	 */
2595#ifdef	__per_cpu_offset
2596#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2597#else
2598#ifdef	CONFIG_SMP
2599#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2600#else
2601#define KDB_PCU(cpu) 0
2602#endif
2603#endif
2604	for_each_online_cpu(cpu) {
2605		if (KDB_FLAG(CMD_INTERRUPT))
2606			return 0;
2607
2608		if (whichcpu != ~0UL && whichcpu != cpu)
2609			continue;
2610		addr = symaddr + KDB_PCU(cpu);
2611		diag = kdb_getword(&val, addr, bytesperword);
2612		if (diag) {
2613			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2614				   "read, diag=%d\n", cpu, addr, diag);
2615			continue;
2616		}
2617		kdb_printf("%5d ", cpu);
2618		kdb_md_line(fmtstr, addr,
2619			bytesperword == KDB_WORD_SIZE,
2620			1, bytesperword, 1, 1, 0);
2621	}
2622#undef KDB_PCU
2623	return 0;
2624}
2625
2626/*
2627 * display help for the use of cmd | grep pattern
2628 */
2629static int kdb_grep_help(int argc, const char **argv)
2630{
2631	kdb_printf("Usage of  cmd args | grep pattern:\n");
2632	kdb_printf("  Any command's output may be filtered through an ");
2633	kdb_printf("emulated 'pipe'.\n");
2634	kdb_printf("  'grep' is just a key word.\n");
2635	kdb_printf("  The pattern may include a very limited set of "
2636		   "metacharacters:\n");
2637	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2638	kdb_printf("  And if there are spaces in the pattern, you may "
2639		   "quote it:\n");
2640	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2641		   " or \"^pat tern$\"\n");
2642	return 0;
2643}
2644
2645/*
2646 * kdb_register_flags - This function is used to register a kernel
2647 * 	debugger command.
2648 * Inputs:
2649 *	cmd	Command name
2650 *	func	Function to execute the command
2651 *	usage	A simple usage string showing arguments
2652 *	help	A simple help string describing command
2653 *	repeat	Does the command auto repeat on enter?
2654 * Returns:
2655 *	zero for success, one if a duplicate command.
2656 */
2657#define kdb_command_extend 50	/* arbitrary */
2658int kdb_register_flags(char *cmd,
2659		       kdb_func_t func,
2660		       char *usage,
2661		       char *help,
2662		       short minlen,
2663		       kdb_cmdflags_t flags)
2664{
2665	int i;
2666	kdbtab_t *kp;
2667
2668	/*
2669	 *  Brute force method to determine duplicates
2670	 */
2671	for_each_kdbcmd(kp, i) {
2672		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2673			kdb_printf("Duplicate kdb command registered: "
2674				"%s, func %px help %s\n", cmd, func, help);
2675			return 1;
2676		}
2677	}
2678
2679	/*
2680	 * Insert command into first available location in table
2681	 */
2682	for_each_kdbcmd(kp, i) {
2683		if (kp->cmd_name == NULL)
2684			break;
2685	}
2686
2687	if (i >= kdb_max_commands) {
2688		kdbtab_t *new = kmalloc_array(kdb_max_commands -
2689						KDB_BASE_CMD_MAX +
2690						kdb_command_extend,
2691					      sizeof(*new),
2692					      GFP_KDB);
2693		if (!new) {
2694			kdb_printf("Could not allocate new kdb_command "
2695				   "table\n");
2696			return 1;
2697		}
2698		if (kdb_commands) {
2699			memcpy(new, kdb_commands,
2700			  (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new));
2701			kfree(kdb_commands);
2702		}
2703		memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0,
2704		       kdb_command_extend * sizeof(*new));
2705		kdb_commands = new;
2706		kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX;
2707		kdb_max_commands += kdb_command_extend;
2708	}
2709
2710	kp->cmd_name   = cmd;
2711	kp->cmd_func   = func;
2712	kp->cmd_usage  = usage;
2713	kp->cmd_help   = help;
2714	kp->cmd_minlen = minlen;
2715	kp->cmd_flags  = flags;
 
 
 
2716
2717	return 0;
2718}
2719EXPORT_SYMBOL_GPL(kdb_register_flags);
2720
 
 
 
 
 
 
 
 
 
 
 
 
 
2721
2722/*
2723 * kdb_register - Compatibility register function for commands that do
2724 *	not need to specify a repeat state.  Equivalent to
2725 *	kdb_register_flags with flags set to 0.
2726 * Inputs:
2727 *	cmd	Command name
2728 *	func	Function to execute the command
2729 *	usage	A simple usage string showing arguments
2730 *	help	A simple help string describing command
2731 * Returns:
2732 *	zero for success, one if a duplicate command.
2733 */
2734int kdb_register(char *cmd,
2735	     kdb_func_t func,
2736	     char *usage,
2737	     char *help,
2738	     short minlen)
2739{
2740	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2741}
2742EXPORT_SYMBOL_GPL(kdb_register);
2743
2744/*
2745 * kdb_unregister - This function is used to unregister a kernel
2746 *	debugger command.  It is generally called when a module which
2747 *	implements kdb commands is unloaded.
2748 * Inputs:
2749 *	cmd	Command name
2750 * Returns:
2751 *	zero for success, one command not registered.
2752 */
2753int kdb_unregister(char *cmd)
2754{
2755	int i;
2756	kdbtab_t *kp;
2757
2758	/*
2759	 *  find the command.
2760	 */
2761	for_each_kdbcmd(kp, i) {
2762		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2763			kp->cmd_name = NULL;
 
 
2764			return 0;
2765		}
2766	}
2767
2768	/* Couldn't find it.  */
2769	return 1;
2770}
2771EXPORT_SYMBOL_GPL(kdb_unregister);
2772
2773/* Initialize the kdb command table. */
2774static void __init kdb_inittab(void)
2775{
2776	int i;
2777	kdbtab_t *kp;
2778
2779	for_each_kdbcmd(kp, i)
2780		kp->cmd_name = NULL;
2781
2782	kdb_register_flags("md", kdb_md, "<vaddr>",
2783	  "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2784	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2785	kdb_register_flags("mdr", kdb_md, "<vaddr> <bytes>",
2786	  "Display Raw Memory", 0,
2787	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2788	kdb_register_flags("mdp", kdb_md, "<paddr> <bytes>",
2789	  "Display Physical Memory", 0,
2790	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2791	kdb_register_flags("mds", kdb_md, "<vaddr>",
2792	  "Display Memory Symbolically", 0,
2793	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2794	kdb_register_flags("mm", kdb_mm, "<vaddr> <contents>",
2795	  "Modify Memory Contents", 0,
2796	  KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS);
2797	kdb_register_flags("go", kdb_go, "[<vaddr>]",
2798	  "Continue Execution", 1,
2799	  KDB_ENABLE_REG_WRITE | KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2800	kdb_register_flags("rd", kdb_rd, "",
2801	  "Display Registers", 0,
2802	  KDB_ENABLE_REG_READ);
2803	kdb_register_flags("rm", kdb_rm, "<reg> <contents>",
2804	  "Modify Registers", 0,
2805	  KDB_ENABLE_REG_WRITE);
2806	kdb_register_flags("ef", kdb_ef, "<vaddr>",
2807	  "Display exception frame", 0,
2808	  KDB_ENABLE_MEM_READ);
2809	kdb_register_flags("bt", kdb_bt, "[<vaddr>]",
2810	  "Stack traceback", 1,
2811	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2812	kdb_register_flags("btp", kdb_bt, "<pid>",
2813	  "Display stack for process <pid>", 0,
2814	  KDB_ENABLE_INSPECT);
2815	kdb_register_flags("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
2816	  "Backtrace all processes matching state flag", 0,
2817	  KDB_ENABLE_INSPECT);
2818	kdb_register_flags("btc", kdb_bt, "",
2819	  "Backtrace current process on each cpu", 0,
2820	  KDB_ENABLE_INSPECT);
2821	kdb_register_flags("btt", kdb_bt, "<vaddr>",
2822	  "Backtrace process given its struct task address", 0,
2823	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2824	kdb_register_flags("env", kdb_env, "",
2825	  "Show environment variables", 0,
2826	  KDB_ENABLE_ALWAYS_SAFE);
2827	kdb_register_flags("set", kdb_set, "",
2828	  "Set environment variables", 0,
2829	  KDB_ENABLE_ALWAYS_SAFE);
2830	kdb_register_flags("help", kdb_help, "",
2831	  "Display Help Message", 1,
2832	  KDB_ENABLE_ALWAYS_SAFE);
2833	kdb_register_flags("?", kdb_help, "",
2834	  "Display Help Message", 0,
2835	  KDB_ENABLE_ALWAYS_SAFE);
2836	kdb_register_flags("cpu", kdb_cpu, "<cpunum>",
2837	  "Switch to new cpu", 0,
2838	  KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2839	kdb_register_flags("kgdb", kdb_kgdb, "",
2840	  "Enter kgdb mode", 0, 0);
2841	kdb_register_flags("ps", kdb_ps, "[<flags>|A]",
2842	  "Display active task list", 0,
2843	  KDB_ENABLE_INSPECT);
2844	kdb_register_flags("pid", kdb_pid, "<pidnum>",
2845	  "Switch to another task", 0,
2846	  KDB_ENABLE_INSPECT);
2847	kdb_register_flags("reboot", kdb_reboot, "",
2848	  "Reboot the machine immediately", 0,
2849	  KDB_ENABLE_REBOOT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2850#if defined(CONFIG_MODULES)
2851	kdb_register_flags("lsmod", kdb_lsmod, "",
2852	  "List loaded kernel modules", 0,
2853	  KDB_ENABLE_INSPECT);
 
 
 
2854#endif
2855#if defined(CONFIG_MAGIC_SYSRQ)
2856	kdb_register_flags("sr", kdb_sr, "<key>",
2857	  "Magic SysRq key", 0,
2858	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
2859#endif
2860#if defined(CONFIG_PRINTK)
2861	kdb_register_flags("dmesg", kdb_dmesg, "[lines]",
2862	  "Display syslog buffer", 0,
2863	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
2864#endif
2865	if (arch_kgdb_ops.enable_nmi) {
2866		kdb_register_flags("disable_nmi", kdb_disable_nmi, "",
2867		  "Disable NMI entry to KDB", 0,
2868		  KDB_ENABLE_ALWAYS_SAFE);
2869	}
2870	kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2871	  "Define a set of commands, down to endefcmd", 0,
2872	  KDB_ENABLE_ALWAYS_SAFE);
2873	kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
2874	  "Send a signal to a process", 0,
2875	  KDB_ENABLE_SIGNAL);
2876	kdb_register_flags("summary", kdb_summary, "",
2877	  "Summarize the system", 4,
2878	  KDB_ENABLE_ALWAYS_SAFE);
2879	kdb_register_flags("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]",
2880	  "Display per_cpu variables", 3,
2881	  KDB_ENABLE_MEM_READ);
2882	kdb_register_flags("grephelp", kdb_grep_help, "",
2883	  "Display help on | grep", 0,
2884	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2885}
2886
2887/* Execute any commands defined in kdb_cmds.  */
2888static void __init kdb_cmd_init(void)
2889{
2890	int i, diag;
2891	for (i = 0; kdb_cmds[i]; ++i) {
2892		diag = kdb_parse(kdb_cmds[i]);
2893		if (diag)
2894			kdb_printf("kdb command %s failed, kdb diag %d\n",
2895				kdb_cmds[i], diag);
2896	}
2897	if (defcmd_in_progress) {
2898		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2899		kdb_parse("endefcmd");
2900	}
2901}
2902
2903/* Initialize kdb_printf, breakpoint tables and kdb state */
2904void __init kdb_init(int lvl)
2905{
2906	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2907	int i;
2908
2909	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2910		return;
2911	for (i = kdb_init_lvl; i < lvl; i++) {
2912		switch (i) {
2913		case KDB_NOT_INITIALIZED:
2914			kdb_inittab();		/* Initialize Command Table */
2915			kdb_initbptab();	/* Initialize Breakpoints */
2916			break;
2917		case KDB_INIT_EARLY:
2918			kdb_cmd_init();		/* Build kdb_cmds tables */
2919			break;
2920		}
2921	}
2922	kdb_init_lvl = lvl;
2923}
v5.14.15
   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/list.h>
  37#include <linux/notifier.h>
  38#include <linux/interrupt.h>
  39#include <linux/delay.h>
  40#include <linux/nmi.h>
  41#include <linux/time.h>
  42#include <linux/ptrace.h>
  43#include <linux/sysctl.h>
  44#include <linux/cpu.h>
  45#include <linux/kdebug.h>
  46#include <linux/proc_fs.h>
  47#include <linux/uaccess.h>
  48#include <linux/slab.h>
  49#include "kdb_private.h"
  50
  51#undef	MODULE_PARAM_PREFIX
  52#define	MODULE_PARAM_PREFIX "kdb."
  53
  54static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  55module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  56
  57char kdb_grep_string[KDB_GREP_STRLEN];
  58int kdb_grepping_flag;
  59EXPORT_SYMBOL(kdb_grepping_flag);
  60int kdb_grep_leading;
  61int kdb_grep_trailing;
  62
  63/*
  64 * Kernel debugger state flags
  65 */
  66unsigned int kdb_flags;
  67
  68/*
  69 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  70 * single thread processors through the kernel debugger.
  71 */
  72int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  73int kdb_nextline = 1;
  74int kdb_state;			/* General KDB state */
  75
  76struct task_struct *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_cmds_head describes the available commands. */
  89static LIST_HEAD(kdb_cmds_head);
 
 
 
 
 
 
 
  90
  91typedef struct _kdbmsg {
  92	int	km_diag;	/* kdb diagnostic */
  93	char	*km_msg;	/* Corresponding message text */
  94} kdbmsg_t;
  95
  96#define KDBMSG(msgnum, text) \
  97	{ KDB_##msgnum, text }
  98
  99static kdbmsg_t kdbmsgs[] = {
 100	KDBMSG(NOTFOUND, "Command Not Found"),
 101	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 102	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 103	       "8 is only allowed on 64 bit systems"),
 104	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 105	KDBMSG(NOTENV, "Cannot find environment variable"),
 106	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 107	KDBMSG(NOTIMP, "Command not implemented"),
 108	KDBMSG(ENVFULL, "Environment full"),
 109	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 110	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 111#ifdef CONFIG_CPU_XSCALE
 112	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 113#else
 114	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 115#endif
 116	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 117	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 118	KDBMSG(BADMODE, "Invalid IDMODE"),
 119	KDBMSG(BADINT, "Illegal numeric value"),
 120	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 121	KDBMSG(BADREG, "Invalid register name"),
 122	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 123	KDBMSG(BADLENGTH, "Invalid length field"),
 124	KDBMSG(NOBP, "No Breakpoint exists"),
 125	KDBMSG(BADADDR, "Invalid address"),
 126	KDBMSG(NOPERM, "Permission denied"),
 127};
 128#undef KDBMSG
 129
 130static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 131
 132
 133/*
 134 * Initial environment.   This is all kept static and local to
 135 * this file.   We don't want to rely on the memory allocation
 136 * mechanisms in the kernel, so we use a very limited allocate-only
 137 * heap for new and altered environment variables.  The entire
 138 * environment is limited to a fixed number of entries (add more
 139 * to __env[] if required) and a fixed amount of heap (add more to
 140 * KDB_ENVBUFSIZE if required).
 141 */
 142
 143static char *__env[31] = {
 144#if defined(CONFIG_SMP)
 145	"PROMPT=[%d]kdb> ",
 146#else
 147	"PROMPT=kdb> ",
 148#endif
 149	"MOREPROMPT=more> ",
 150	"RADIX=16",
 151	"MDCOUNT=8",		/* lines of md output */
 152	KDB_PLATFORM_ENV,
 153	"DTABCOUNT=30",
 154	"NOSECT=1",
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 155};
 156
 157static const int __nenv = ARRAY_SIZE(__env);
 158
 159struct task_struct *kdb_curr_task(int cpu)
 160{
 161	struct task_struct *p = curr_task(cpu);
 162#ifdef	_TIF_MCA_INIT
 163	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 164		p = krp->p;
 165#endif
 166	return p;
 167}
 168
 169/*
 170 * Check whether the flags of the current command and the permissions
 171 * of the kdb console has allow a command to be run.
 172 */
 173static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 174				   bool no_args)
 175{
 176	/* permissions comes from userspace so needs massaging slightly */
 177	permissions &= KDB_ENABLE_MASK;
 178	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 179
 180	/* some commands change group when launched with no arguments */
 181	if (no_args)
 182		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 183
 184	flags |= KDB_ENABLE_ALL;
 185
 186	return permissions & flags;
 187}
 188
 189/*
 190 * kdbgetenv - This function will return the character string value of
 191 *	an environment variable.
 192 * Parameters:
 193 *	match	A character string representing an environment variable.
 194 * Returns:
 195 *	NULL	No environment variable matches 'match'
 196 *	char*	Pointer to string value of environment variable.
 197 */
 198char *kdbgetenv(const char *match)
 199{
 200	char **ep = __env;
 201	int matchlen = strlen(match);
 202	int i;
 203
 204	for (i = 0; i < __nenv; i++) {
 205		char *e = *ep++;
 206
 207		if (!e)
 208			continue;
 209
 210		if ((strncmp(match, e, matchlen) == 0)
 211		 && ((e[matchlen] == '\0')
 212		   || (e[matchlen] == '='))) {
 213			char *cp = strchr(e, '=');
 214			return cp ? ++cp : "";
 215		}
 216	}
 217	return NULL;
 218}
 219
 220/*
 221 * kdballocenv - This function is used to allocate bytes for
 222 *	environment entries.
 223 * Parameters:
 224 *	match	A character string representing a numeric value
 225 * Outputs:
 226 *	*value  the unsigned long representation of the env variable 'match'
 227 * Returns:
 228 *	Zero on success, a kdb diagnostic on failure.
 229 * Remarks:
 230 *	We use a static environment buffer (envbuffer) to hold the values
 231 *	of dynamically generated environment variables (see kdb_set).  Buffer
 232 *	space once allocated is never free'd, so over time, the amount of space
 233 *	(currently 512 bytes) will be exhausted if env variables are changed
 234 *	frequently.
 235 */
 236static char *kdballocenv(size_t bytes)
 237{
 238#define	KDB_ENVBUFSIZE	512
 239	static char envbuffer[KDB_ENVBUFSIZE];
 240	static int envbufsize;
 241	char *ep = NULL;
 242
 243	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 244		ep = &envbuffer[envbufsize];
 245		envbufsize += bytes;
 246	}
 247	return ep;
 248}
 249
 250/*
 251 * kdbgetulenv - This function will return the value of an unsigned
 252 *	long-valued environment variable.
 253 * Parameters:
 254 *	match	A character string representing a numeric value
 255 * Outputs:
 256 *	*value  the unsigned long representation of the env variable 'match'
 257 * Returns:
 258 *	Zero on success, a kdb diagnostic on failure.
 259 */
 260static int kdbgetulenv(const char *match, unsigned long *value)
 261{
 262	char *ep;
 263
 264	ep = kdbgetenv(match);
 265	if (!ep)
 266		return KDB_NOTENV;
 267	if (strlen(ep) == 0)
 268		return KDB_NOENVVALUE;
 269
 270	*value = simple_strtoul(ep, NULL, 0);
 271
 272	return 0;
 273}
 274
 275/*
 276 * kdbgetintenv - This function will return the value of an
 277 *	integer-valued environment variable.
 278 * Parameters:
 279 *	match	A character string representing an integer-valued env variable
 280 * Outputs:
 281 *	*value  the integer representation of the environment variable 'match'
 282 * Returns:
 283 *	Zero on success, a kdb diagnostic on failure.
 284 */
 285int kdbgetintenv(const char *match, int *value)
 286{
 287	unsigned long val;
 288	int diag;
 289
 290	diag = kdbgetulenv(match, &val);
 291	if (!diag)
 292		*value = (int) val;
 293	return diag;
 294}
 295
 296/*
 297 * kdb_setenv() - Alter an existing environment variable or create a new one.
 298 * @var: Name of the variable
 299 * @val: Value of the variable
 300 *
 301 * Return: Zero on success, a kdb diagnostic on failure.
 302 */
 303static int kdb_setenv(const char *var, const char *val)
 304{
 305	int i;
 306	char *ep;
 307	size_t varlen, vallen;
 308
 309	varlen = strlen(var);
 310	vallen = strlen(val);
 311	ep = kdballocenv(varlen + vallen + 2);
 312	if (ep == (char *)0)
 313		return KDB_ENVBUFFULL;
 314
 315	sprintf(ep, "%s=%s", var, val);
 316
 317	for (i = 0; i < __nenv; i++) {
 318		if (__env[i]
 319		 && ((strncmp(__env[i], var, varlen) == 0)
 320		   && ((__env[i][varlen] == '\0')
 321		    || (__env[i][varlen] == '=')))) {
 322			__env[i] = ep;
 323			return 0;
 324		}
 325	}
 326
 327	/*
 328	 * Wasn't existing variable.  Fit into slot.
 329	 */
 330	for (i = 0; i < __nenv-1; i++) {
 331		if (__env[i] == (char *)0) {
 332			__env[i] = ep;
 333			return 0;
 334		}
 335	}
 336
 337	return KDB_ENVFULL;
 338}
 339
 340/*
 341 * kdb_printenv() - Display the current environment variables.
 342 */
 343static void kdb_printenv(void)
 344{
 345	int i;
 346
 347	for (i = 0; i < __nenv; i++) {
 348		if (__env[i])
 349			kdb_printf("%s\n", __env[i]);
 350	}
 351}
 352
 353/*
 354 * kdbgetularg - This function will convert a numeric string into an
 355 *	unsigned long value.
 356 * Parameters:
 357 *	arg	A character string representing a numeric value
 358 * Outputs:
 359 *	*value  the unsigned long representation of arg.
 360 * Returns:
 361 *	Zero on success, a kdb diagnostic on failure.
 362 */
 363int kdbgetularg(const char *arg, unsigned long *value)
 364{
 365	char *endp;
 366	unsigned long val;
 367
 368	val = simple_strtoul(arg, &endp, 0);
 369
 370	if (endp == arg) {
 371		/*
 372		 * Also try base 16, for us folks too lazy to type the
 373		 * leading 0x...
 374		 */
 375		val = simple_strtoul(arg, &endp, 16);
 376		if (endp == arg)
 377			return KDB_BADINT;
 378	}
 379
 380	*value = val;
 381
 382	return 0;
 383}
 384
 385int kdbgetu64arg(const char *arg, u64 *value)
 386{
 387	char *endp;
 388	u64 val;
 389
 390	val = simple_strtoull(arg, &endp, 0);
 391
 392	if (endp == arg) {
 393
 394		val = simple_strtoull(arg, &endp, 16);
 395		if (endp == arg)
 396			return KDB_BADINT;
 397	}
 398
 399	*value = val;
 400
 401	return 0;
 402}
 403
 404/*
 405 * kdb_set - This function implements the 'set' command.  Alter an
 406 *	existing environment variable or create a new one.
 407 */
 408int kdb_set(int argc, const char **argv)
 409{
 
 
 
 
 410	/*
 411	 * we can be invoked two ways:
 412	 *   set var=value    argv[1]="var", argv[2]="value"
 413	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 414	 * - if the latter, shift 'em down.
 415	 */
 416	if (argc == 3) {
 417		argv[2] = argv[3];
 418		argc--;
 419	}
 420
 421	if (argc != 2)
 422		return KDB_ARGCOUNT;
 423
 424	/*
 425	 * Censor sensitive variables
 426	 */
 427	if (strcmp(argv[1], "PROMPT") == 0 &&
 428	    !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
 429		return KDB_NOPERM;
 430
 431	/*
 432	 * Check for internal variables
 433	 */
 434	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 435		unsigned int debugflags;
 436		char *cp;
 437
 438		debugflags = simple_strtoul(argv[2], &cp, 0);
 439		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 440			kdb_printf("kdb: illegal debug flags '%s'\n",
 441				    argv[2]);
 442			return 0;
 443		}
 444		kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
 
 445			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 446
 447		return 0;
 448	}
 449
 450	/*
 451	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 452	 * name, argv[2] = value.
 453	 */
 454	return kdb_setenv(argv[1], argv[2]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 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 *	hexadecimal), 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	bool 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 bool 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 = false;
 678		if (!s->count)
 679			s->usable = false;
 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 = kcalloc(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 = false;
 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_array(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 = true;
 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 = true;
 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 (!str_has_prefix(cp, "grep ")) {
 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 delimiter (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 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	list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1008		/*
1009		 * If this command is allowed to be abbreviated,
1010		 * check to see if this is it.
1011		 */
1012		if (tp->cmd_minlen && (strlen(argv[0]) <= tp->cmd_minlen) &&
1013		    (strncmp(argv[0], tp->cmd_name, tp->cmd_minlen) == 0))
1014			break;
 
 
 
 
 
 
 
1015
1016		if (strcmp(argv[0], tp->cmd_name) == 0)
1017			break;
 
1018	}
1019
1020	/*
1021	 * If we don't find a command by this name, see if the first
1022	 * few characters of this match any of the known commands.
1023	 * e.g., md1c20 should match md.
1024	 */
1025	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1026		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1027			if (strncmp(argv[0], tp->cmd_name,
1028				    strlen(tp->cmd_name)) == 0)
1029				break;
 
 
 
 
1030		}
1031	}
1032
1033	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1034		int result;
1035
1036		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1037			return KDB_NOPERM;
1038
1039		KDB_STATE_SET(CMD);
1040		result = (*tp->cmd_func)(argc-1, (const char **)argv);
1041		if (result && ignore_errors && result > KDB_CMD_GO)
1042			result = 0;
1043		KDB_STATE_CLEAR(CMD);
1044
1045		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1046			return result;
1047
1048		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1049		if (argv[argc])
1050			*(argv[argc]) = '\0';
1051		return result;
1052	}
1053
1054	/*
1055	 * If the input with which we were presented does not
1056	 * map to an existing command, attempt to parse it as an
1057	 * address argument and display the result.   Useful for
1058	 * obtaining the address of a variable, or the nearest symbol
1059	 * to an address contained in a register.
1060	 */
1061	{
1062		unsigned long value;
1063		char *name = NULL;
1064		long offset;
1065		int nextarg = 0;
1066
1067		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1068				  &value, &offset, &name)) {
1069			return KDB_NOTFOUND;
1070		}
1071
1072		kdb_printf("%s = ", argv[0]);
1073		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1074		kdb_printf("\n");
1075		return 0;
1076	}
1077}
1078
1079
1080static int handle_ctrl_cmd(char *cmd)
1081{
1082#define CTRL_P	16
1083#define CTRL_N	14
1084
1085	/* initial situation */
1086	if (cmd_head == cmd_tail)
1087		return 0;
1088	switch (*cmd) {
1089	case CTRL_P:
1090		if (cmdptr != cmd_tail)
1091			cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) %
1092				 KDB_CMD_HISTORY_COUNT;
1093		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1094		return 1;
1095	case CTRL_N:
1096		if (cmdptr != cmd_head)
1097			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1098		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1099		return 1;
1100	}
1101	return 0;
1102}
1103
1104/*
1105 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1106 *	the system immediately, or loop for ever on failure.
1107 */
1108static int kdb_reboot(int argc, const char **argv)
1109{
1110	emergency_restart();
1111	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1112	while (1)
1113		cpu_relax();
1114	/* NOTREACHED */
1115	return 0;
1116}
1117
1118static void kdb_dumpregs(struct pt_regs *regs)
1119{
1120	int old_lvl = console_loglevel;
1121	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1122	kdb_trap_printk++;
1123	show_regs(regs);
1124	kdb_trap_printk--;
1125	kdb_printf("\n");
1126	console_loglevel = old_lvl;
1127}
1128
1129static void kdb_set_current_task(struct task_struct *p)
1130{
1131	kdb_current_task = p;
1132
1133	if (kdb_task_has_cpu(p)) {
1134		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1135		return;
1136	}
1137	kdb_current_regs = NULL;
1138}
1139
1140static void drop_newline(char *buf)
1141{
1142	size_t len = strlen(buf);
1143
1144	if (len == 0)
1145		return;
1146	if (*(buf + len - 1) == '\n')
1147		*(buf + len - 1) = '\0';
1148}
1149
1150/*
1151 * kdb_local - The main code for kdb.  This routine is invoked on a
1152 *	specific processor, it is not global.  The main kdb() routine
1153 *	ensures that only one processor at a time is in this routine.
1154 *	This code is called with the real reason code on the first
1155 *	entry to a kdb session, thereafter it is called with reason
1156 *	SWITCH, even if the user goes back to the original cpu.
1157 * Inputs:
1158 *	reason		The reason KDB was invoked
1159 *	error		The hardware-defined error code
1160 *	regs		The exception frame at time of fault/breakpoint.
1161 *	db_result	Result code from the break or debug point.
1162 * Returns:
1163 *	0	KDB was invoked for an event which it wasn't responsible
1164 *	1	KDB handled the event for which it was invoked.
1165 *	KDB_CMD_GO	User typed 'go'.
1166 *	KDB_CMD_CPU	User switched to another cpu.
1167 *	KDB_CMD_SS	Single step.
1168 */
1169static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1170		     kdb_dbtrap_t db_result)
1171{
1172	char *cmdbuf;
1173	int diag;
1174	struct task_struct *kdb_current =
1175		kdb_curr_task(raw_smp_processor_id());
1176
1177	KDB_DEBUG_STATE("kdb_local 1", reason);
1178	kdb_go_count = 0;
1179	if (reason == KDB_REASON_DEBUG) {
1180		/* special case below */
1181	} else {
1182		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1183			   kdb_current, kdb_current ? kdb_current->pid : 0);
1184#if defined(CONFIG_SMP)
1185		kdb_printf("on processor %d ", raw_smp_processor_id());
1186#endif
1187	}
1188
1189	switch (reason) {
1190	case KDB_REASON_DEBUG:
1191	{
1192		/*
1193		 * If re-entering kdb after a single step
1194		 * command, don't print the message.
1195		 */
1196		switch (db_result) {
1197		case KDB_DB_BPT:
1198			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1199				   kdb_current, kdb_current->pid);
1200#if defined(CONFIG_SMP)
1201			kdb_printf("on processor %d ", raw_smp_processor_id());
1202#endif
1203			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1204				   instruction_pointer(regs));
1205			break;
1206		case KDB_DB_SS:
1207			break;
1208		case KDB_DB_SSBPT:
1209			KDB_DEBUG_STATE("kdb_local 4", reason);
1210			return 1;	/* kdba_db_trap did the work */
1211		default:
1212			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1213				   db_result);
1214			break;
1215		}
1216
1217	}
1218		break;
1219	case KDB_REASON_ENTER:
1220		if (KDB_STATE(KEYBOARD))
1221			kdb_printf("due to Keyboard Entry\n");
1222		else
1223			kdb_printf("due to KDB_ENTER()\n");
1224		break;
1225	case KDB_REASON_KEYBOARD:
1226		KDB_STATE_SET(KEYBOARD);
1227		kdb_printf("due to Keyboard Entry\n");
1228		break;
1229	case KDB_REASON_ENTER_SLAVE:
1230		/* drop through, slaves only get released via cpu switch */
1231	case KDB_REASON_SWITCH:
1232		kdb_printf("due to cpu switch\n");
1233		break;
1234	case KDB_REASON_OOPS:
1235		kdb_printf("Oops: %s\n", kdb_diemsg);
1236		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1237			   instruction_pointer(regs));
1238		kdb_dumpregs(regs);
1239		break;
1240	case KDB_REASON_SYSTEM_NMI:
1241		kdb_printf("due to System NonMaskable Interrupt\n");
1242		break;
1243	case KDB_REASON_NMI:
1244		kdb_printf("due to NonMaskable Interrupt @ "
1245			   kdb_machreg_fmt "\n",
1246			   instruction_pointer(regs));
1247		break;
1248	case KDB_REASON_SSTEP:
1249	case KDB_REASON_BREAK:
1250		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1251			   reason == KDB_REASON_BREAK ?
1252			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1253		/*
1254		 * Determine if this breakpoint is one that we
1255		 * are interested in.
1256		 */
1257		if (db_result != KDB_DB_BPT) {
1258			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1259				   db_result);
1260			KDB_DEBUG_STATE("kdb_local 6", reason);
1261			return 0;	/* Not for us, dismiss it */
1262		}
1263		break;
1264	case KDB_REASON_RECURSE:
1265		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1266			   instruction_pointer(regs));
1267		break;
1268	default:
1269		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1270		KDB_DEBUG_STATE("kdb_local 8", reason);
1271		return 0;	/* Not for us, dismiss it */
1272	}
1273
1274	while (1) {
1275		/*
1276		 * Initialize pager context.
1277		 */
1278		kdb_nextline = 1;
1279		KDB_STATE_CLEAR(SUPPRESS);
1280		kdb_grepping_flag = 0;
1281		/* ensure the old search does not leak into '/' commands */
1282		kdb_grep_string[0] = '\0';
1283
1284		cmdbuf = cmd_cur;
1285		*cmdbuf = '\0';
1286		*(cmd_hist[cmd_head]) = '\0';
1287
1288do_full_getstr:
1289		/* PROMPT can only be set if we have MEM_READ permission. */
1290		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1291			 raw_smp_processor_id());
 
 
 
1292		if (defcmd_in_progress)
1293			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1294
1295		/*
1296		 * Fetch command from keyboard
1297		 */
1298		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1299		if (*cmdbuf != '\n') {
1300			if (*cmdbuf < 32) {
1301				if (cmdptr == cmd_head) {
1302					strscpy(cmd_hist[cmd_head], cmd_cur,
1303						CMD_BUFLEN);
1304					*(cmd_hist[cmd_head] +
1305					  strlen(cmd_hist[cmd_head])-1) = '\0';
1306				}
1307				if (!handle_ctrl_cmd(cmdbuf))
1308					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1309				cmdbuf = cmd_cur;
1310				goto do_full_getstr;
1311			} else {
1312				strscpy(cmd_hist[cmd_head], cmd_cur,
1313					CMD_BUFLEN);
1314			}
1315
1316			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1317			if (cmd_head == cmd_tail)
1318				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1319		}
1320
1321		cmdptr = cmd_head;
1322		diag = kdb_parse(cmdbuf);
1323		if (diag == KDB_NOTFOUND) {
1324			drop_newline(cmdbuf);
1325			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1326			diag = 0;
1327		}
1328		if (diag == KDB_CMD_GO
1329		 || diag == KDB_CMD_CPU
1330		 || diag == KDB_CMD_SS
1331		 || diag == KDB_CMD_KGDB)
1332			break;
1333
1334		if (diag)
1335			kdb_cmderror(diag);
1336	}
1337	KDB_DEBUG_STATE("kdb_local 9", diag);
1338	return diag;
1339}
1340
1341
1342/*
1343 * kdb_print_state - Print the state data for the current processor
1344 *	for debugging.
1345 * Inputs:
1346 *	text		Identifies the debug point
1347 *	value		Any integer value to be printed, e.g. reason code.
1348 */
1349void kdb_print_state(const char *text, int value)
1350{
1351	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1352		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1353		   kdb_state);
1354}
1355
1356/*
1357 * kdb_main_loop - After initial setup and assignment of the
1358 *	controlling cpu, all cpus are in this loop.  One cpu is in
1359 *	control and will issue the kdb prompt, the others will spin
1360 *	until 'go' or cpu switch.
1361 *
1362 *	To get a consistent view of the kernel stacks for all
1363 *	processes, this routine is invoked from the main kdb code via
1364 *	an architecture specific routine.  kdba_main_loop is
1365 *	responsible for making the kernel stacks consistent for all
1366 *	processes, there should be no difference between a blocked
1367 *	process and a running process as far as kdb is concerned.
1368 * Inputs:
1369 *	reason		The reason KDB was invoked
1370 *	error		The hardware-defined error code
1371 *	reason2		kdb's current reason code.
1372 *			Initially error but can change
1373 *			according to kdb state.
1374 *	db_result	Result code from break or debug point.
1375 *	regs		The exception frame at time of fault/breakpoint.
1376 *			should always be valid.
1377 * Returns:
1378 *	0	KDB was invoked for an event which it wasn't responsible
1379 *	1	KDB handled the event for which it was invoked.
1380 */
1381int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1382	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1383{
1384	int result = 1;
1385	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1386	while (1) {
1387		/*
1388		 * All processors except the one that is in control
1389		 * will spin here.
1390		 */
1391		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1392		while (KDB_STATE(HOLD_CPU)) {
1393			/* state KDB is turned off by kdb_cpu to see if the
1394			 * other cpus are still live, each cpu in this loop
1395			 * turns it back on.
1396			 */
1397			if (!KDB_STATE(KDB))
1398				KDB_STATE_SET(KDB);
1399		}
1400
1401		KDB_STATE_CLEAR(SUPPRESS);
1402		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1403		if (KDB_STATE(LEAVING))
1404			break;	/* Another cpu said 'go' */
1405		/* Still using kdb, this processor is in control */
1406		result = kdb_local(reason2, error, regs, db_result);
1407		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1408
1409		if (result == KDB_CMD_CPU)
1410			break;
1411
1412		if (result == KDB_CMD_SS) {
1413			KDB_STATE_SET(DOING_SS);
1414			break;
1415		}
1416
1417		if (result == KDB_CMD_KGDB) {
1418			if (!KDB_STATE(DOING_KGDB))
1419				kdb_printf("Entering please attach debugger "
1420					   "or use $D#44+ or $3#33\n");
1421			break;
1422		}
1423		if (result && result != 1 && result != KDB_CMD_GO)
1424			kdb_printf("\nUnexpected kdb_local return code %d\n",
1425				   result);
1426		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1427		break;
1428	}
1429	if (KDB_STATE(DOING_SS))
1430		KDB_STATE_CLEAR(SSBPT);
1431
1432	/* Clean up any keyboard devices before leaving */
1433	kdb_kbd_cleanup_state();
1434
1435	return result;
1436}
1437
1438/*
1439 * kdb_mdr - This function implements the guts of the 'mdr', memory
1440 * read command.
1441 *	mdr  <addr arg>,<byte count>
1442 * Inputs:
1443 *	addr	Start address
1444 *	count	Number of bytes
1445 * Returns:
1446 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1447 */
1448static int kdb_mdr(unsigned long addr, unsigned int count)
1449{
1450	unsigned char c;
1451	while (count--) {
1452		if (kdb_getarea(c, addr))
1453			return 0;
1454		kdb_printf("%02x", c);
1455		addr++;
1456	}
1457	kdb_printf("\n");
1458	return 0;
1459}
1460
1461/*
1462 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1463 *	'md8' 'mdr' and 'mds' commands.
1464 *
1465 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1466 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1467 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1468 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1469 *	mdr  <addr arg>,<byte count>
1470 */
1471static void kdb_md_line(const char *fmtstr, unsigned long addr,
1472			int symbolic, int nosect, int bytesperword,
1473			int num, int repeat, int phys)
1474{
1475	/* print just one line of data */
1476	kdb_symtab_t symtab;
1477	char cbuf[32];
1478	char *c = cbuf;
1479	int i;
1480	int j;
1481	unsigned long word;
1482
1483	memset(cbuf, '\0', sizeof(cbuf));
1484	if (phys)
1485		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1486	else
1487		kdb_printf(kdb_machreg_fmt0 " ", addr);
1488
1489	for (i = 0; i < num && repeat--; i++) {
1490		if (phys) {
1491			if (kdb_getphysword(&word, addr, bytesperword))
1492				break;
1493		} else if (kdb_getword(&word, addr, bytesperword))
1494			break;
1495		kdb_printf(fmtstr, word);
1496		if (symbolic)
1497			kdbnearsym(word, &symtab);
1498		else
1499			memset(&symtab, 0, sizeof(symtab));
1500		if (symtab.sym_name) {
1501			kdb_symbol_print(word, &symtab, 0);
1502			if (!nosect) {
1503				kdb_printf("\n");
1504				kdb_printf("                       %s %s "
1505					   kdb_machreg_fmt " "
1506					   kdb_machreg_fmt " "
1507					   kdb_machreg_fmt, symtab.mod_name,
1508					   symtab.sec_name, symtab.sec_start,
1509					   symtab.sym_start, symtab.sym_end);
1510			}
1511			addr += bytesperword;
1512		} else {
1513			union {
1514				u64 word;
1515				unsigned char c[8];
1516			} wc;
1517			unsigned char *cp;
1518#ifdef	__BIG_ENDIAN
1519			cp = wc.c + 8 - bytesperword;
1520#else
1521			cp = wc.c;
1522#endif
1523			wc.word = word;
1524#define printable_char(c) \
1525	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1526			for (j = 0; j < bytesperword; j++)
1527				*c++ = printable_char(*cp++);
1528			addr += bytesperword;
1529#undef printable_char
1530		}
1531	}
1532	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1533		   " ", cbuf);
1534}
1535
1536static int kdb_md(int argc, const char **argv)
1537{
1538	static unsigned long last_addr;
1539	static int last_radix, last_bytesperword, last_repeat;
1540	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1541	int nosect = 0;
1542	char fmtchar, fmtstr[64];
1543	unsigned long addr;
1544	unsigned long word;
1545	long offset = 0;
1546	int symbolic = 0;
1547	int valid = 0;
1548	int phys = 0;
1549	int raw = 0;
1550
1551	kdbgetintenv("MDCOUNT", &mdcount);
1552	kdbgetintenv("RADIX", &radix);
1553	kdbgetintenv("BYTESPERWORD", &bytesperword);
1554
1555	/* Assume 'md <addr>' and start with environment values */
1556	repeat = mdcount * 16 / bytesperword;
1557
1558	if (strcmp(argv[0], "mdr") == 0) {
1559		if (argc == 2 || (argc == 0 && last_addr != 0))
1560			valid = raw = 1;
1561		else
1562			return KDB_ARGCOUNT;
1563	} else if (isdigit(argv[0][2])) {
1564		bytesperword = (int)(argv[0][2] - '0');
1565		if (bytesperword == 0) {
1566			bytesperword = last_bytesperword;
1567			if (bytesperword == 0)
1568				bytesperword = 4;
1569		}
1570		last_bytesperword = bytesperword;
1571		repeat = mdcount * 16 / bytesperword;
1572		if (!argv[0][3])
1573			valid = 1;
1574		else if (argv[0][3] == 'c' && argv[0][4]) {
1575			char *p;
1576			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1577			mdcount = ((repeat * bytesperword) + 15) / 16;
1578			valid = !*p;
1579		}
1580		last_repeat = repeat;
1581	} else if (strcmp(argv[0], "md") == 0)
1582		valid = 1;
1583	else if (strcmp(argv[0], "mds") == 0)
1584		valid = 1;
1585	else if (strcmp(argv[0], "mdp") == 0) {
1586		phys = valid = 1;
1587	}
1588	if (!valid)
1589		return KDB_NOTFOUND;
1590
1591	if (argc == 0) {
1592		if (last_addr == 0)
1593			return KDB_ARGCOUNT;
1594		addr = last_addr;
1595		radix = last_radix;
1596		bytesperword = last_bytesperword;
1597		repeat = last_repeat;
1598		if (raw)
1599			mdcount = repeat;
1600		else
1601			mdcount = ((repeat * bytesperword) + 15) / 16;
1602	}
1603
1604	if (argc) {
1605		unsigned long val;
1606		int diag, nextarg = 1;
1607		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1608				     &offset, NULL);
1609		if (diag)
1610			return diag;
1611		if (argc > nextarg+2)
1612			return KDB_ARGCOUNT;
1613
1614		if (argc >= nextarg) {
1615			diag = kdbgetularg(argv[nextarg], &val);
1616			if (!diag) {
1617				mdcount = (int) val;
1618				if (raw)
1619					repeat = mdcount;
1620				else
1621					repeat = mdcount * 16 / bytesperword;
1622			}
1623		}
1624		if (argc >= nextarg+1) {
1625			diag = kdbgetularg(argv[nextarg+1], &val);
1626			if (!diag)
1627				radix = (int) val;
1628		}
1629	}
1630
1631	if (strcmp(argv[0], "mdr") == 0) {
1632		int ret;
1633		last_addr = addr;
1634		ret = kdb_mdr(addr, mdcount);
1635		last_addr += mdcount;
1636		last_repeat = mdcount;
1637		last_bytesperword = bytesperword; // to make REPEAT happy
1638		return ret;
1639	}
1640
1641	switch (radix) {
1642	case 10:
1643		fmtchar = 'd';
1644		break;
1645	case 16:
1646		fmtchar = 'x';
1647		break;
1648	case 8:
1649		fmtchar = 'o';
1650		break;
1651	default:
1652		return KDB_BADRADIX;
1653	}
1654
1655	last_radix = radix;
1656
1657	if (bytesperword > KDB_WORD_SIZE)
1658		return KDB_BADWIDTH;
1659
1660	switch (bytesperword) {
1661	case 8:
1662		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1663		break;
1664	case 4:
1665		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1666		break;
1667	case 2:
1668		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1669		break;
1670	case 1:
1671		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1672		break;
1673	default:
1674		return KDB_BADWIDTH;
1675	}
1676
1677	last_repeat = repeat;
1678	last_bytesperword = bytesperword;
1679
1680	if (strcmp(argv[0], "mds") == 0) {
1681		symbolic = 1;
1682		/* Do not save these changes as last_*, they are temporary mds
1683		 * overrides.
1684		 */
1685		bytesperword = KDB_WORD_SIZE;
1686		repeat = mdcount;
1687		kdbgetintenv("NOSECT", &nosect);
1688	}
1689
1690	/* Round address down modulo BYTESPERWORD */
1691
1692	addr &= ~(bytesperword-1);
1693
1694	while (repeat > 0) {
1695		unsigned long a;
1696		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1697
1698		if (KDB_FLAG(CMD_INTERRUPT))
1699			return 0;
1700		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1701			if (phys) {
1702				if (kdb_getphysword(&word, a, bytesperword)
1703						|| word)
1704					break;
1705			} else if (kdb_getword(&word, a, bytesperword) || word)
1706				break;
1707		}
1708		n = min(num, repeat);
1709		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1710			    num, repeat, phys);
1711		addr += bytesperword * n;
1712		repeat -= n;
1713		z = (z + num - 1) / num;
1714		if (z > 2) {
1715			int s = num * (z-2);
1716			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1717				   " zero suppressed\n",
1718				addr, addr + bytesperword * s - 1);
1719			addr += bytesperword * s;
1720			repeat -= s;
1721		}
1722	}
1723	last_addr = addr;
1724
1725	return 0;
1726}
1727
1728/*
1729 * kdb_mm - This function implements the 'mm' command.
1730 *	mm address-expression new-value
1731 * Remarks:
1732 *	mm works on machine words, mmW works on bytes.
1733 */
1734static int kdb_mm(int argc, const char **argv)
1735{
1736	int diag;
1737	unsigned long addr;
1738	long offset = 0;
1739	unsigned long contents;
1740	int nextarg;
1741	int width;
1742
1743	if (argv[0][2] && !isdigit(argv[0][2]))
1744		return KDB_NOTFOUND;
1745
1746	if (argc < 2)
1747		return KDB_ARGCOUNT;
1748
1749	nextarg = 1;
1750	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1751	if (diag)
1752		return diag;
1753
1754	if (nextarg > argc)
1755		return KDB_ARGCOUNT;
1756	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1757	if (diag)
1758		return diag;
1759
1760	if (nextarg != argc + 1)
1761		return KDB_ARGCOUNT;
1762
1763	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1764	diag = kdb_putword(addr, contents, width);
1765	if (diag)
1766		return diag;
1767
1768	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1769
1770	return 0;
1771}
1772
1773/*
1774 * kdb_go - This function implements the 'go' command.
1775 *	go [address-expression]
1776 */
1777static int kdb_go(int argc, const char **argv)
1778{
1779	unsigned long addr;
1780	int diag;
1781	int nextarg;
1782	long offset;
1783
1784	if (raw_smp_processor_id() != kdb_initial_cpu) {
1785		kdb_printf("go must execute on the entry cpu, "
1786			   "please use \"cpu %d\" and then execute go\n",
1787			   kdb_initial_cpu);
1788		return KDB_BADCPUNUM;
1789	}
1790	if (argc == 1) {
1791		nextarg = 1;
1792		diag = kdbgetaddrarg(argc, argv, &nextarg,
1793				     &addr, &offset, NULL);
1794		if (diag)
1795			return diag;
1796	} else if (argc) {
1797		return KDB_ARGCOUNT;
1798	}
1799
1800	diag = KDB_CMD_GO;
1801	if (KDB_FLAG(CATASTROPHIC)) {
1802		kdb_printf("Catastrophic error detected\n");
1803		kdb_printf("kdb_continue_catastrophic=%d, ",
1804			kdb_continue_catastrophic);
1805		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1806			kdb_printf("type go a second time if you really want "
1807				   "to continue\n");
1808			return 0;
1809		}
1810		if (kdb_continue_catastrophic == 2) {
1811			kdb_printf("forcing reboot\n");
1812			kdb_reboot(0, NULL);
1813		}
1814		kdb_printf("attempting to continue\n");
1815	}
1816	return diag;
1817}
1818
1819/*
1820 * kdb_rd - This function implements the 'rd' command.
1821 */
1822static int kdb_rd(int argc, const char **argv)
1823{
1824	int len = kdb_check_regs();
1825#if DBG_MAX_REG_NUM > 0
1826	int i;
1827	char *rname;
1828	int rsize;
1829	u64 reg64;
1830	u32 reg32;
1831	u16 reg16;
1832	u8 reg8;
1833
1834	if (len)
1835		return len;
1836
1837	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1838		rsize = dbg_reg_def[i].size * 2;
1839		if (rsize > 16)
1840			rsize = 2;
1841		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1842			len = 0;
1843			kdb_printf("\n");
1844		}
1845		if (len)
1846			len += kdb_printf("  ");
1847		switch(dbg_reg_def[i].size * 8) {
1848		case 8:
1849			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1850			if (!rname)
1851				break;
1852			len += kdb_printf("%s: %02x", rname, reg8);
1853			break;
1854		case 16:
1855			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1856			if (!rname)
1857				break;
1858			len += kdb_printf("%s: %04x", rname, reg16);
1859			break;
1860		case 32:
1861			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1862			if (!rname)
1863				break;
1864			len += kdb_printf("%s: %08x", rname, reg32);
1865			break;
1866		case 64:
1867			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1868			if (!rname)
1869				break;
1870			len += kdb_printf("%s: %016llx", rname, reg64);
1871			break;
1872		default:
1873			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1874		}
1875	}
1876	kdb_printf("\n");
1877#else
1878	if (len)
1879		return len;
1880
1881	kdb_dumpregs(kdb_current_regs);
1882#endif
1883	return 0;
1884}
1885
1886/*
1887 * kdb_rm - This function implements the 'rm' (register modify)  command.
1888 *	rm register-name new-contents
1889 * Remarks:
1890 *	Allows register modification with the same restrictions as gdb
1891 */
1892static int kdb_rm(int argc, const char **argv)
1893{
1894#if DBG_MAX_REG_NUM > 0
1895	int diag;
1896	const char *rname;
1897	int i;
1898	u64 reg64;
1899	u32 reg32;
1900	u16 reg16;
1901	u8 reg8;
1902
1903	if (argc != 2)
1904		return KDB_ARGCOUNT;
1905	/*
1906	 * Allow presence or absence of leading '%' symbol.
1907	 */
1908	rname = argv[1];
1909	if (*rname == '%')
1910		rname++;
1911
1912	diag = kdbgetu64arg(argv[2], &reg64);
1913	if (diag)
1914		return diag;
1915
1916	diag = kdb_check_regs();
1917	if (diag)
1918		return diag;
1919
1920	diag = KDB_BADREG;
1921	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1922		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1923			diag = 0;
1924			break;
1925		}
1926	}
1927	if (!diag) {
1928		switch(dbg_reg_def[i].size * 8) {
1929		case 8:
1930			reg8 = reg64;
1931			dbg_set_reg(i, &reg8, kdb_current_regs);
1932			break;
1933		case 16:
1934			reg16 = reg64;
1935			dbg_set_reg(i, &reg16, kdb_current_regs);
1936			break;
1937		case 32:
1938			reg32 = reg64;
1939			dbg_set_reg(i, &reg32, kdb_current_regs);
1940			break;
1941		case 64:
1942			dbg_set_reg(i, &reg64, kdb_current_regs);
1943			break;
1944		}
1945	}
1946	return diag;
1947#else
1948	kdb_printf("ERROR: Register set currently not implemented\n");
1949    return 0;
1950#endif
1951}
1952
1953#if defined(CONFIG_MAGIC_SYSRQ)
1954/*
1955 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1956 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1957 *		sr <magic-sysrq-code>
1958 */
1959static int kdb_sr(int argc, const char **argv)
1960{
1961	bool check_mask =
1962	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1963
1964	if (argc != 1)
1965		return KDB_ARGCOUNT;
1966
1967	kdb_trap_printk++;
1968	__handle_sysrq(*argv[1], check_mask);
1969	kdb_trap_printk--;
1970
1971	return 0;
1972}
1973#endif	/* CONFIG_MAGIC_SYSRQ */
1974
1975/*
1976 * kdb_ef - This function implements the 'regs' (display exception
1977 *	frame) command.  This command takes an address and expects to
1978 *	find an exception frame at that address, formats and prints
1979 *	it.
1980 *		regs address-expression
1981 * Remarks:
1982 *	Not done yet.
1983 */
1984static int kdb_ef(int argc, const char **argv)
1985{
1986	int diag;
1987	unsigned long addr;
1988	long offset;
1989	int nextarg;
1990
1991	if (argc != 1)
1992		return KDB_ARGCOUNT;
1993
1994	nextarg = 1;
1995	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1996	if (diag)
1997		return diag;
1998	show_regs((struct pt_regs *)addr);
1999	return 0;
2000}
2001
2002#if defined(CONFIG_MODULES)
2003/*
2004 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2005 *	currently loaded kernel modules.
2006 *	Mostly taken from userland lsmod.
2007 */
2008static int kdb_lsmod(int argc, const char **argv)
2009{
2010	struct module *mod;
2011
2012	if (argc != 0)
2013		return KDB_ARGCOUNT;
2014
2015	kdb_printf("Module                  Size  modstruct     Used by\n");
2016	list_for_each_entry(mod, kdb_modules, list) {
2017		if (mod->state == MODULE_STATE_UNFORMED)
2018			continue;
2019
2020		kdb_printf("%-20s%8u  0x%px ", mod->name,
2021			   mod->core_layout.size, (void *)mod);
2022#ifdef CONFIG_MODULE_UNLOAD
2023		kdb_printf("%4d ", module_refcount(mod));
2024#endif
2025		if (mod->state == MODULE_STATE_GOING)
2026			kdb_printf(" (Unloading)");
2027		else if (mod->state == MODULE_STATE_COMING)
2028			kdb_printf(" (Loading)");
2029		else
2030			kdb_printf(" (Live)");
2031		kdb_printf(" 0x%px", mod->core_layout.base);
2032
2033#ifdef CONFIG_MODULE_UNLOAD
2034		{
2035			struct module_use *use;
2036			kdb_printf(" [ ");
2037			list_for_each_entry(use, &mod->source_list,
2038					    source_list)
2039				kdb_printf("%s ", use->target->name);
2040			kdb_printf("]\n");
2041		}
2042#endif
2043	}
2044
2045	return 0;
2046}
2047
2048#endif	/* CONFIG_MODULES */
2049
2050/*
2051 * kdb_env - This function implements the 'env' command.  Display the
2052 *	current environment variables.
2053 */
2054
2055static int kdb_env(int argc, const char **argv)
2056{
2057	kdb_printenv();
 
 
 
 
 
2058
2059	if (KDB_DEBUG(MASK))
2060		kdb_printf("KDBDEBUG=0x%x\n",
2061			(kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2062
2063	return 0;
2064}
2065
2066#ifdef CONFIG_PRINTK
2067/*
2068 * kdb_dmesg - This function implements the 'dmesg' command to display
2069 *	the contents of the syslog buffer.
2070 *		dmesg [lines] [adjust]
2071 */
2072static int kdb_dmesg(int argc, const char **argv)
2073{
2074	int diag;
2075	int logging;
2076	int lines = 0;
2077	int adjust = 0;
2078	int n = 0;
2079	int skip = 0;
2080	struct kmsg_dump_iter iter;
2081	size_t len;
2082	char buf[201];
2083
2084	if (argc > 2)
2085		return KDB_ARGCOUNT;
2086	if (argc) {
2087		char *cp;
2088		lines = simple_strtol(argv[1], &cp, 0);
2089		if (*cp)
2090			lines = 0;
2091		if (argc > 1) {
2092			adjust = simple_strtoul(argv[2], &cp, 0);
2093			if (*cp || adjust < 0)
2094				adjust = 0;
2095		}
2096	}
2097
2098	/* disable LOGGING if set */
2099	diag = kdbgetintenv("LOGGING", &logging);
2100	if (!diag && logging) {
2101		const char *setargs[] = { "set", "LOGGING", "0" };
2102		kdb_set(2, setargs);
2103	}
2104
2105	kmsg_dump_rewind(&iter);
2106	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2107		n++;
2108
2109	if (lines < 0) {
2110		if (adjust >= n)
2111			kdb_printf("buffer only contains %d lines, nothing "
2112				   "printed\n", n);
2113		else if (adjust - lines >= n)
2114			kdb_printf("buffer only contains %d lines, last %d "
2115				   "lines printed\n", n, n - adjust);
2116		skip = adjust;
2117		lines = abs(lines);
2118	} else if (lines > 0) {
2119		skip = n - lines - adjust;
2120		lines = abs(lines);
2121		if (adjust >= n) {
2122			kdb_printf("buffer only contains %d lines, "
2123				   "nothing printed\n", n);
2124			skip = n;
2125		} else if (skip < 0) {
2126			lines += skip;
2127			skip = 0;
2128			kdb_printf("buffer only contains %d lines, first "
2129				   "%d lines printed\n", n, lines);
2130		}
2131	} else {
2132		lines = n;
2133	}
2134
2135	if (skip >= n || skip < 0)
2136		return 0;
2137
2138	kmsg_dump_rewind(&iter);
2139	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2140		if (skip) {
2141			skip--;
2142			continue;
2143		}
2144		if (!lines--)
2145			break;
2146		if (KDB_FLAG(CMD_INTERRUPT))
2147			return 0;
2148
2149		kdb_printf("%.*s\n", (int)len - 1, buf);
2150	}
2151
2152	return 0;
2153}
2154#endif /* CONFIG_PRINTK */
2155
2156/* Make sure we balance enable/disable calls, must disable first. */
2157static atomic_t kdb_nmi_disabled;
2158
2159static int kdb_disable_nmi(int argc, const char *argv[])
2160{
2161	if (atomic_read(&kdb_nmi_disabled))
2162		return 0;
2163	atomic_set(&kdb_nmi_disabled, 1);
2164	arch_kgdb_ops.enable_nmi(0);
2165	return 0;
2166}
2167
2168static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2169{
2170	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2171		return -EINVAL;
2172	arch_kgdb_ops.enable_nmi(1);
2173	return 0;
2174}
2175
2176static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2177	.set = kdb_param_enable_nmi,
2178};
2179module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2180
2181/*
2182 * kdb_cpu - This function implements the 'cpu' command.
2183 *	cpu	[<cpunum>]
2184 * Returns:
2185 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2186 */
2187static void kdb_cpu_status(void)
2188{
2189	int i, start_cpu, first_print = 1;
2190	char state, prev_state = '?';
2191
2192	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2193	kdb_printf("Available cpus: ");
2194	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2195		if (!cpu_online(i)) {
2196			state = 'F';	/* cpu is offline */
2197		} else if (!kgdb_info[i].enter_kgdb) {
2198			state = 'D';	/* cpu is online but unresponsive */
2199		} else {
2200			state = ' ';	/* cpu is responding to kdb */
2201			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2202				state = 'I';	/* idle task */
2203		}
2204		if (state != prev_state) {
2205			if (prev_state != '?') {
2206				if (!first_print)
2207					kdb_printf(", ");
2208				first_print = 0;
2209				kdb_printf("%d", start_cpu);
2210				if (start_cpu < i-1)
2211					kdb_printf("-%d", i-1);
2212				if (prev_state != ' ')
2213					kdb_printf("(%c)", prev_state);
2214			}
2215			prev_state = state;
2216			start_cpu = i;
2217		}
2218	}
2219	/* print the trailing cpus, ignoring them if they are all offline */
2220	if (prev_state != 'F') {
2221		if (!first_print)
2222			kdb_printf(", ");
2223		kdb_printf("%d", start_cpu);
2224		if (start_cpu < i-1)
2225			kdb_printf("-%d", i-1);
2226		if (prev_state != ' ')
2227			kdb_printf("(%c)", prev_state);
2228	}
2229	kdb_printf("\n");
2230}
2231
2232static int kdb_cpu(int argc, const char **argv)
2233{
2234	unsigned long cpunum;
2235	int diag;
2236
2237	if (argc == 0) {
2238		kdb_cpu_status();
2239		return 0;
2240	}
2241
2242	if (argc != 1)
2243		return KDB_ARGCOUNT;
2244
2245	diag = kdbgetularg(argv[1], &cpunum);
2246	if (diag)
2247		return diag;
2248
2249	/*
2250	 * Validate cpunum
2251	 */
2252	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2253		return KDB_BADCPUNUM;
2254
2255	dbg_switch_cpu = cpunum;
2256
2257	/*
2258	 * Switch to other cpu
2259	 */
2260	return KDB_CMD_CPU;
2261}
2262
2263/* The user may not realize that ps/bta with no parameters does not print idle
2264 * or sleeping system daemon processes, so tell them how many were suppressed.
2265 */
2266void kdb_ps_suppressed(void)
2267{
2268	int idle = 0, daemon = 0;
2269	unsigned long mask_I = kdb_task_state_string("I"),
2270		      mask_M = kdb_task_state_string("M");
2271	unsigned long cpu;
2272	const struct task_struct *p, *g;
2273	for_each_online_cpu(cpu) {
2274		p = kdb_curr_task(cpu);
2275		if (kdb_task_state(p, mask_I))
2276			++idle;
2277	}
2278	for_each_process_thread(g, p) {
2279		if (kdb_task_state(p, mask_M))
2280			++daemon;
2281	}
2282	if (idle || daemon) {
2283		if (idle)
2284			kdb_printf("%d idle process%s (state I)%s\n",
2285				   idle, idle == 1 ? "" : "es",
2286				   daemon ? " and " : "");
2287		if (daemon)
2288			kdb_printf("%d sleeping system daemon (state M) "
2289				   "process%s", daemon,
2290				   daemon == 1 ? "" : "es");
2291		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2292	}
2293}
2294
2295/*
2296 * kdb_ps - This function implements the 'ps' command which shows a
2297 *	list of the active processes.
2298 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2299 */
2300void kdb_ps1(const struct task_struct *p)
2301{
2302	int cpu;
2303	unsigned long tmp;
2304
2305	if (!p ||
2306	    copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2307		return;
2308
2309	cpu = kdb_process_cpu(p);
2310	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2311		   (void *)p, p->pid, p->parent->pid,
2312		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2313		   kdb_task_state_char(p),
2314		   (void *)(&p->thread),
2315		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2316		   p->comm);
2317	if (kdb_task_has_cpu(p)) {
2318		if (!KDB_TSK(cpu)) {
2319			kdb_printf("  Error: no saved data for this cpu\n");
2320		} else {
2321			if (KDB_TSK(cpu) != p)
2322				kdb_printf("  Error: does not match running "
2323				   "process table (0x%px)\n", KDB_TSK(cpu));
2324		}
2325	}
2326}
2327
2328static int kdb_ps(int argc, const char **argv)
2329{
2330	struct task_struct *g, *p;
2331	unsigned long mask, cpu;
2332
2333	if (argc == 0)
2334		kdb_ps_suppressed();
2335	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2336		(int)(2*sizeof(void *))+2, "Task Addr",
2337		(int)(2*sizeof(void *))+2, "Thread");
2338	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2339	/* Run the active tasks first */
2340	for_each_online_cpu(cpu) {
2341		if (KDB_FLAG(CMD_INTERRUPT))
2342			return 0;
2343		p = kdb_curr_task(cpu);
2344		if (kdb_task_state(p, mask))
2345			kdb_ps1(p);
2346	}
2347	kdb_printf("\n");
2348	/* Now the real tasks */
2349	for_each_process_thread(g, p) {
2350		if (KDB_FLAG(CMD_INTERRUPT))
2351			return 0;
2352		if (kdb_task_state(p, mask))
2353			kdb_ps1(p);
2354	}
2355
2356	return 0;
2357}
2358
2359/*
2360 * kdb_pid - This function implements the 'pid' command which switches
2361 *	the currently active process.
2362 *		pid [<pid> | R]
2363 */
2364static int kdb_pid(int argc, const char **argv)
2365{
2366	struct task_struct *p;
2367	unsigned long val;
2368	int diag;
2369
2370	if (argc > 1)
2371		return KDB_ARGCOUNT;
2372
2373	if (argc) {
2374		if (strcmp(argv[1], "R") == 0) {
2375			p = KDB_TSK(kdb_initial_cpu);
2376		} else {
2377			diag = kdbgetularg(argv[1], &val);
2378			if (diag)
2379				return KDB_BADINT;
2380
2381			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2382			if (!p) {
2383				kdb_printf("No task with pid=%d\n", (pid_t)val);
2384				return 0;
2385			}
2386		}
2387		kdb_set_current_task(p);
2388	}
2389	kdb_printf("KDB current process is %s(pid=%d)\n",
2390		   kdb_current_task->comm,
2391		   kdb_current_task->pid);
2392
2393	return 0;
2394}
2395
2396static int kdb_kgdb(int argc, const char **argv)
2397{
2398	return KDB_CMD_KGDB;
2399}
2400
2401/*
2402 * kdb_help - This function implements the 'help' and '?' commands.
2403 */
2404static int kdb_help(int argc, const char **argv)
2405{
2406	kdbtab_t *kt;
 
2407
2408	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2409	kdb_printf("-----------------------------"
2410		   "-----------------------------\n");
2411	list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2412		char *space = "";
2413		if (KDB_FLAG(CMD_INTERRUPT))
2414			return 0;
 
 
2415		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2416			continue;
2417		if (strlen(kt->cmd_usage) > 20)
2418			space = "\n                                    ";
2419		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2420			   kt->cmd_usage, space, kt->cmd_help);
2421	}
2422	return 0;
2423}
2424
2425/*
2426 * kdb_kill - This function implements the 'kill' commands.
2427 */
2428static int kdb_kill(int argc, const char **argv)
2429{
2430	long sig, pid;
2431	char *endp;
2432	struct task_struct *p;
2433
2434	if (argc != 2)
2435		return KDB_ARGCOUNT;
2436
2437	sig = simple_strtol(argv[1], &endp, 0);
2438	if (*endp)
2439		return KDB_BADINT;
2440	if ((sig >= 0) || !valid_signal(-sig)) {
2441		kdb_printf("Invalid signal parameter.<-signal>\n");
2442		return 0;
2443	}
2444	sig = -sig;
2445
2446	pid = simple_strtol(argv[2], &endp, 0);
2447	if (*endp)
2448		return KDB_BADINT;
2449	if (pid <= 0) {
2450		kdb_printf("Process ID must be large than 0.\n");
2451		return 0;
2452	}
2453
2454	/* Find the process. */
2455	p = find_task_by_pid_ns(pid, &init_pid_ns);
2456	if (!p) {
2457		kdb_printf("The specified process isn't found.\n");
2458		return 0;
2459	}
2460	p = p->group_leader;
2461	kdb_send_sig(p, sig);
2462	return 0;
2463}
2464
2465/*
2466 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2467 * I cannot call that code directly from kdb, it has an unconditional
2468 * cli()/sti() and calls routines that take locks which can stop the debugger.
2469 */
2470static void kdb_sysinfo(struct sysinfo *val)
2471{
2472	u64 uptime = ktime_get_mono_fast_ns();
2473
2474	memset(val, 0, sizeof(*val));
2475	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2476	val->loads[0] = avenrun[0];
2477	val->loads[1] = avenrun[1];
2478	val->loads[2] = avenrun[2];
2479	val->procs = nr_threads-1;
2480	si_meminfo(val);
2481
2482	return;
2483}
2484
2485/*
2486 * kdb_summary - This function implements the 'summary' command.
2487 */
2488static int kdb_summary(int argc, const char **argv)
2489{
2490	time64_t now;
 
2491	struct sysinfo val;
2492
2493	if (argc)
2494		return KDB_ARGCOUNT;
2495
2496	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2497	kdb_printf("release    %s\n", init_uts_ns.name.release);
2498	kdb_printf("version    %s\n", init_uts_ns.name.version);
2499	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2500	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2501	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2502
2503	now = __ktime_get_real_seconds();
2504	kdb_printf("date       %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
 
 
 
 
 
 
2505	kdb_sysinfo(&val);
2506	kdb_printf("uptime     ");
2507	if (val.uptime > (24*60*60)) {
2508		int days = val.uptime / (24*60*60);
2509		val.uptime %= (24*60*60);
2510		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2511	}
2512	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2513
2514	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2515		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2516		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2517		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2518
2519	/* Display in kilobytes */
2520#define K(x) ((x) << (PAGE_SHIFT - 10))
2521	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2522		   "Buffers:        %8lu kB\n",
2523		   K(val.totalram), K(val.freeram), K(val.bufferram));
2524	return 0;
2525}
2526
2527/*
2528 * kdb_per_cpu - This function implements the 'per_cpu' command.
2529 */
2530static int kdb_per_cpu(int argc, const char **argv)
2531{
2532	char fmtstr[64];
2533	int cpu, diag, nextarg = 1;
2534	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2535
2536	if (argc < 1 || argc > 3)
2537		return KDB_ARGCOUNT;
2538
2539	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2540	if (diag)
2541		return diag;
2542
2543	if (argc >= 2) {
2544		diag = kdbgetularg(argv[2], &bytesperword);
2545		if (diag)
2546			return diag;
2547	}
2548	if (!bytesperword)
2549		bytesperword = KDB_WORD_SIZE;
2550	else if (bytesperword > KDB_WORD_SIZE)
2551		return KDB_BADWIDTH;
2552	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2553	if (argc >= 3) {
2554		diag = kdbgetularg(argv[3], &whichcpu);
2555		if (diag)
2556			return diag;
2557		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2558			kdb_printf("cpu %ld is not online\n", whichcpu);
2559			return KDB_BADCPUNUM;
2560		}
2561	}
2562
2563	/* Most architectures use __per_cpu_offset[cpu], some use
2564	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2565	 */
2566#ifdef	__per_cpu_offset
2567#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2568#else
2569#ifdef	CONFIG_SMP
2570#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2571#else
2572#define KDB_PCU(cpu) 0
2573#endif
2574#endif
2575	for_each_online_cpu(cpu) {
2576		if (KDB_FLAG(CMD_INTERRUPT))
2577			return 0;
2578
2579		if (whichcpu != ~0UL && whichcpu != cpu)
2580			continue;
2581		addr = symaddr + KDB_PCU(cpu);
2582		diag = kdb_getword(&val, addr, bytesperword);
2583		if (diag) {
2584			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2585				   "read, diag=%d\n", cpu, addr, diag);
2586			continue;
2587		}
2588		kdb_printf("%5d ", cpu);
2589		kdb_md_line(fmtstr, addr,
2590			bytesperword == KDB_WORD_SIZE,
2591			1, bytesperword, 1, 1, 0);
2592	}
2593#undef KDB_PCU
2594	return 0;
2595}
2596
2597/*
2598 * display help for the use of cmd | grep pattern
2599 */
2600static int kdb_grep_help(int argc, const char **argv)
2601{
2602	kdb_printf("Usage of  cmd args | grep pattern:\n");
2603	kdb_printf("  Any command's output may be filtered through an ");
2604	kdb_printf("emulated 'pipe'.\n");
2605	kdb_printf("  'grep' is just a key word.\n");
2606	kdb_printf("  The pattern may include a very limited set of "
2607		   "metacharacters:\n");
2608	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2609	kdb_printf("  And if there are spaces in the pattern, you may "
2610		   "quote it:\n");
2611	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2612		   " or \"^pat tern$\"\n");
2613	return 0;
2614}
2615
2616/*
2617 * kdb_register_flags - This function is used to register a kernel
2618 * 	debugger command.
2619 * Inputs:
2620 *	cmd	Command name
2621 *	func	Function to execute the command
2622 *	usage	A simple usage string showing arguments
2623 *	help	A simple help string describing command
2624 *	repeat	Does the command auto repeat on enter?
2625 * Returns:
2626 *	zero for success, one if a duplicate command.
2627 */
 
2628int kdb_register_flags(char *cmd,
2629		       kdb_func_t func,
2630		       char *usage,
2631		       char *help,
2632		       short minlen,
2633		       kdb_cmdflags_t flags)
2634{
 
2635	kdbtab_t *kp;
2636
2637	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2638		if (strcmp(kp->cmd_name, cmd) == 0) {
 
 
 
2639			kdb_printf("Duplicate kdb command registered: "
2640				"%s, func %px help %s\n", cmd, func, help);
2641			return 1;
2642		}
2643	}
2644
2645	kp = kmalloc(sizeof(*kp), GFP_KDB);
2646	if (!kp) {
2647		kdb_printf("Could not allocate new kdb_command table\n");
2648		return 1;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2649	}
2650
2651	kp->cmd_name   = cmd;
2652	kp->cmd_func   = func;
2653	kp->cmd_usage  = usage;
2654	kp->cmd_help   = help;
2655	kp->cmd_minlen = minlen;
2656	kp->cmd_flags  = flags;
2657	kp->is_dynamic = true;
2658
2659	list_add_tail(&kp->list_node, &kdb_cmds_head);
2660
2661	return 0;
2662}
2663EXPORT_SYMBOL_GPL(kdb_register_flags);
2664
2665/*
2666 * kdb_register_table() - This function is used to register a kdb command
2667 *                        table.
2668 * @kp: pointer to kdb command table
2669 * @len: length of kdb command table
2670 */
2671void kdb_register_table(kdbtab_t *kp, size_t len)
2672{
2673	while (len--) {
2674		list_add_tail(&kp->list_node, &kdb_cmds_head);
2675		kp++;
2676	}
2677}
2678
2679/*
2680 * kdb_register - Compatibility register function for commands that do
2681 *	not need to specify a repeat state.  Equivalent to
2682 *	kdb_register_flags with flags set to 0.
2683 * Inputs:
2684 *	cmd	Command name
2685 *	func	Function to execute the command
2686 *	usage	A simple usage string showing arguments
2687 *	help	A simple help string describing command
2688 * Returns:
2689 *	zero for success, one if a duplicate command.
2690 */
2691int kdb_register(char *cmd,
2692	     kdb_func_t func,
2693	     char *usage,
2694	     char *help,
2695	     short minlen)
2696{
2697	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2698}
2699EXPORT_SYMBOL_GPL(kdb_register);
2700
2701/*
2702 * kdb_unregister - This function is used to unregister a kernel
2703 *	debugger command.  It is generally called when a module which
2704 *	implements kdb commands is unloaded.
2705 * Inputs:
2706 *	cmd	Command name
2707 * Returns:
2708 *	zero for success, one command not registered.
2709 */
2710int kdb_unregister(char *cmd)
2711{
 
2712	kdbtab_t *kp;
2713
2714	/*
2715	 *  find the command.
2716	 */
2717	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2718		if (strcmp(kp->cmd_name, cmd) == 0) {
2719			list_del(&kp->list_node);
2720			if (kp->is_dynamic)
2721				kfree(kp);
2722			return 0;
2723		}
2724	}
2725
2726	/* Couldn't find it.  */
2727	return 1;
2728}
2729EXPORT_SYMBOL_GPL(kdb_unregister);
2730
2731static kdbtab_t maintab[] = {
2732	{	.cmd_name = "md",
2733		.cmd_func = kdb_md,
2734		.cmd_usage = "<vaddr>",
2735		.cmd_help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2736		.cmd_minlen = 1,
2737		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2738	},
2739	{	.cmd_name = "mdr",
2740		.cmd_func = kdb_md,
2741		.cmd_usage = "<vaddr> <bytes>",
2742		.cmd_help = "Display Raw Memory",
2743		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2744	},
2745	{	.cmd_name = "mdp",
2746		.cmd_func = kdb_md,
2747		.cmd_usage = "<paddr> <bytes>",
2748		.cmd_help = "Display Physical Memory",
2749		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2750	},
2751	{	.cmd_name = "mds",
2752		.cmd_func = kdb_md,
2753		.cmd_usage = "<vaddr>",
2754		.cmd_help = "Display Memory Symbolically",
2755		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2756	},
2757	{	.cmd_name = "mm",
2758		.cmd_func = kdb_mm,
2759		.cmd_usage = "<vaddr> <contents>",
2760		.cmd_help = "Modify Memory Contents",
2761		.cmd_flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2762	},
2763	{	.cmd_name = "go",
2764		.cmd_func = kdb_go,
2765		.cmd_usage = "[<vaddr>]",
2766		.cmd_help = "Continue Execution",
2767		.cmd_minlen = 1,
2768		.cmd_flags = KDB_ENABLE_REG_WRITE |
2769			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2770	},
2771	{	.cmd_name = "rd",
2772		.cmd_func = kdb_rd,
2773		.cmd_usage = "",
2774		.cmd_help = "Display Registers",
2775		.cmd_flags = KDB_ENABLE_REG_READ,
2776	},
2777	{	.cmd_name = "rm",
2778		.cmd_func = kdb_rm,
2779		.cmd_usage = "<reg> <contents>",
2780		.cmd_help = "Modify Registers",
2781		.cmd_flags = KDB_ENABLE_REG_WRITE,
2782	},
2783	{	.cmd_name = "ef",
2784		.cmd_func = kdb_ef,
2785		.cmd_usage = "<vaddr>",
2786		.cmd_help = "Display exception frame",
2787		.cmd_flags = KDB_ENABLE_MEM_READ,
2788	},
2789	{	.cmd_name = "bt",
2790		.cmd_func = kdb_bt,
2791		.cmd_usage = "[<vaddr>]",
2792		.cmd_help = "Stack traceback",
2793		.cmd_minlen = 1,
2794		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2795	},
2796	{	.cmd_name = "btp",
2797		.cmd_func = kdb_bt,
2798		.cmd_usage = "<pid>",
2799		.cmd_help = "Display stack for process <pid>",
2800		.cmd_flags = KDB_ENABLE_INSPECT,
2801	},
2802	{	.cmd_name = "bta",
2803		.cmd_func = kdb_bt,
2804		.cmd_usage = "[D|R|S|T|C|Z|E|U|I|M|A]",
2805		.cmd_help = "Backtrace all processes matching state flag",
2806		.cmd_flags = KDB_ENABLE_INSPECT,
2807	},
2808	{	.cmd_name = "btc",
2809		.cmd_func = kdb_bt,
2810		.cmd_usage = "",
2811		.cmd_help = "Backtrace current process on each cpu",
2812		.cmd_flags = KDB_ENABLE_INSPECT,
2813	},
2814	{	.cmd_name = "btt",
2815		.cmd_func = kdb_bt,
2816		.cmd_usage = "<vaddr>",
2817		.cmd_help = "Backtrace process given its struct task address",
2818		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2819	},
2820	{	.cmd_name = "env",
2821		.cmd_func = kdb_env,
2822		.cmd_usage = "",
2823		.cmd_help = "Show environment variables",
2824		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2825	},
2826	{	.cmd_name = "set",
2827		.cmd_func = kdb_set,
2828		.cmd_usage = "",
2829		.cmd_help = "Set environment variables",
2830		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2831	},
2832	{	.cmd_name = "help",
2833		.cmd_func = kdb_help,
2834		.cmd_usage = "",
2835		.cmd_help = "Display Help Message",
2836		.cmd_minlen = 1,
2837		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2838	},
2839	{	.cmd_name = "?",
2840		.cmd_func = kdb_help,
2841		.cmd_usage = "",
2842		.cmd_help = "Display Help Message",
2843		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2844	},
2845	{	.cmd_name = "cpu",
2846		.cmd_func = kdb_cpu,
2847		.cmd_usage = "<cpunum>",
2848		.cmd_help = "Switch to new cpu",
2849		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2850	},
2851	{	.cmd_name = "kgdb",
2852		.cmd_func = kdb_kgdb,
2853		.cmd_usage = "",
2854		.cmd_help = "Enter kgdb mode",
2855		.cmd_flags = 0,
2856	},
2857	{	.cmd_name = "ps",
2858		.cmd_func = kdb_ps,
2859		.cmd_usage = "[<flags>|A]",
2860		.cmd_help = "Display active task list",
2861		.cmd_flags = KDB_ENABLE_INSPECT,
2862	},
2863	{	.cmd_name = "pid",
2864		.cmd_func = kdb_pid,
2865		.cmd_usage = "<pidnum>",
2866		.cmd_help = "Switch to another task",
2867		.cmd_flags = KDB_ENABLE_INSPECT,
2868	},
2869	{	.cmd_name = "reboot",
2870		.cmd_func = kdb_reboot,
2871		.cmd_usage = "",
2872		.cmd_help = "Reboot the machine immediately",
2873		.cmd_flags = KDB_ENABLE_REBOOT,
2874	},
2875#if defined(CONFIG_MODULES)
2876	{	.cmd_name = "lsmod",
2877		.cmd_func = kdb_lsmod,
2878		.cmd_usage = "",
2879		.cmd_help = "List loaded kernel modules",
2880		.cmd_flags = KDB_ENABLE_INSPECT,
2881	},
2882#endif
2883#if defined(CONFIG_MAGIC_SYSRQ)
2884	{	.cmd_name = "sr",
2885		.cmd_func = kdb_sr,
2886		.cmd_usage = "<key>",
2887		.cmd_help = "Magic SysRq key",
2888		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2889	},
2890#endif
2891#if defined(CONFIG_PRINTK)
2892	{	.cmd_name = "dmesg",
2893		.cmd_func = kdb_dmesg,
2894		.cmd_usage = "[lines]",
2895		.cmd_help = "Display syslog buffer",
2896		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2897	},
2898#endif
2899	{	.cmd_name = "defcmd",
2900		.cmd_func = kdb_defcmd,
2901		.cmd_usage = "name \"usage\" \"help\"",
2902		.cmd_help = "Define a set of commands, down to endefcmd",
2903		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2904	},
2905	{	.cmd_name = "kill",
2906		.cmd_func = kdb_kill,
2907		.cmd_usage = "<-signal> <pid>",
2908		.cmd_help = "Send a signal to a process",
2909		.cmd_flags = KDB_ENABLE_SIGNAL,
2910	},
2911	{	.cmd_name = "summary",
2912		.cmd_func = kdb_summary,
2913		.cmd_usage = "",
2914		.cmd_help = "Summarize the system",
2915		.cmd_minlen = 4,
2916		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2917	},
2918	{	.cmd_name = "per_cpu",
2919		.cmd_func = kdb_per_cpu,
2920		.cmd_usage = "<sym> [<bytes>] [<cpu>]",
2921		.cmd_help = "Display per_cpu variables",
2922		.cmd_minlen = 3,
2923		.cmd_flags = KDB_ENABLE_MEM_READ,
2924	},
2925	{	.cmd_name = "grephelp",
2926		.cmd_func = kdb_grep_help,
2927		.cmd_usage = "",
2928		.cmd_help = "Display help on | grep",
2929		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2930	},
2931};
2932
2933static kdbtab_t nmicmd = {
2934	.cmd_name = "disable_nmi",
2935	.cmd_func = kdb_disable_nmi,
2936	.cmd_usage = "",
2937	.cmd_help = "Disable NMI entry to KDB",
2938	.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2939};
2940
2941/* Initialize the kdb command table. */
2942static void __init kdb_inittab(void)
2943{
2944	kdb_register_table(maintab, ARRAY_SIZE(maintab));
2945	if (arch_kgdb_ops.enable_nmi)
2946		kdb_register_table(&nmicmd, 1);
2947}
2948
2949/* Execute any commands defined in kdb_cmds.  */
2950static void __init kdb_cmd_init(void)
2951{
2952	int i, diag;
2953	for (i = 0; kdb_cmds[i]; ++i) {
2954		diag = kdb_parse(kdb_cmds[i]);
2955		if (diag)
2956			kdb_printf("kdb command %s failed, kdb diag %d\n",
2957				kdb_cmds[i], diag);
2958	}
2959	if (defcmd_in_progress) {
2960		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2961		kdb_parse("endefcmd");
2962	}
2963}
2964
2965/* Initialize kdb_printf, breakpoint tables and kdb state */
2966void __init kdb_init(int lvl)
2967{
2968	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2969	int i;
2970
2971	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2972		return;
2973	for (i = kdb_init_lvl; i < lvl; i++) {
2974		switch (i) {
2975		case KDB_NOT_INITIALIZED:
2976			kdb_inittab();		/* Initialize Command Table */
2977			kdb_initbptab();	/* Initialize Breakpoints */
2978			break;
2979		case KDB_INIT_EARLY:
2980			kdb_cmd_init();		/* Build kdb_cmds tables */
2981			break;
2982		}
2983	}
2984	kdb_init_lvl = lvl;
2985}