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v6.2
   1/*
   2 * Kernel Debugger Architecture Independent Main Code
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
   9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
  10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
  11 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
  12 */
  13
  14#include <linux/ctype.h>
  15#include <linux/types.h>
  16#include <linux/string.h>
  17#include <linux/kernel.h>
  18#include <linux/kmsg_dump.h>
  19#include <linux/reboot.h>
  20#include <linux/sched.h>
  21#include <linux/sched/loadavg.h>
  22#include <linux/sched/stat.h>
  23#include <linux/sched/debug.h>
  24#include <linux/sysrq.h>
  25#include <linux/smp.h>
  26#include <linux/utsname.h>
  27#include <linux/vmalloc.h>
  28#include <linux/atomic.h>
 
  29#include <linux/moduleparam.h>
  30#include <linux/mm.h>
  31#include <linux/init.h>
  32#include <linux/kallsyms.h>
  33#include <linux/kgdb.h>
  34#include <linux/kdb.h>
 
  35#include <linux/notifier.h>
  36#include <linux/interrupt.h>
  37#include <linux/delay.h>
  38#include <linux/nmi.h>
  39#include <linux/time.h>
  40#include <linux/ptrace.h>
  41#include <linux/sysctl.h>
  42#include <linux/cpu.h>
  43#include <linux/kdebug.h>
  44#include <linux/proc_fs.h>
  45#include <linux/uaccess.h>
  46#include <linux/slab.h>
  47#include <linux/security.h>
  48#include "kdb_private.h"
  49
  50#undef	MODULE_PARAM_PREFIX
  51#define	MODULE_PARAM_PREFIX "kdb."
  52
  53static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  54module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  55
  56char kdb_grep_string[KDB_GREP_STRLEN];
  57int kdb_grepping_flag;
  58EXPORT_SYMBOL(kdb_grepping_flag);
  59int kdb_grep_leading;
  60int kdb_grep_trailing;
  61
  62/*
  63 * Kernel debugger state flags
  64 */
  65unsigned int kdb_flags;
  66
  67/*
  68 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  69 * single thread processors through the kernel debugger.
  70 */
  71int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  72int kdb_nextline = 1;
  73int kdb_state;			/* General KDB state */
  74
  75struct task_struct *kdb_current_task;
  76struct pt_regs *kdb_current_regs;
  77
  78const char *kdb_diemsg;
  79static int kdb_go_count;
  80#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
  81static unsigned int kdb_continue_catastrophic =
  82	CONFIG_KDB_CONTINUE_CATASTROPHIC;
  83#else
  84static unsigned int kdb_continue_catastrophic;
  85#endif
  86
  87/* kdb_cmds_head describes the available commands. */
  88static LIST_HEAD(kdb_cmds_head);
  89
  90typedef struct _kdbmsg {
  91	int	km_diag;	/* kdb diagnostic */
  92	char	*km_msg;	/* Corresponding message text */
  93} kdbmsg_t;
  94
  95#define KDBMSG(msgnum, text) \
  96	{ KDB_##msgnum, text }
  97
  98static kdbmsg_t kdbmsgs[] = {
  99	KDBMSG(NOTFOUND, "Command Not Found"),
 100	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 101	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 102	       "8 is only allowed on 64 bit systems"),
 103	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 104	KDBMSG(NOTENV, "Cannot find environment variable"),
 105	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 106	KDBMSG(NOTIMP, "Command not implemented"),
 107	KDBMSG(ENVFULL, "Environment full"),
 108	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 109	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 110#ifdef CONFIG_CPU_XSCALE
 111	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 112#else
 113	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 114#endif
 115	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 116	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 117	KDBMSG(BADMODE, "Invalid IDMODE"),
 118	KDBMSG(BADINT, "Illegal numeric value"),
 119	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 120	KDBMSG(BADREG, "Invalid register name"),
 121	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 122	KDBMSG(BADLENGTH, "Invalid length field"),
 123	KDBMSG(NOBP, "No Breakpoint exists"),
 124	KDBMSG(BADADDR, "Invalid address"),
 125	KDBMSG(NOPERM, "Permission denied"),
 126};
 127#undef KDBMSG
 128
 129static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 130
 131
 132/*
 133 * Initial environment.   This is all kept static and local to
 134 * this file.   We don't want to rely on the memory allocation
 135 * mechanisms in the kernel, so we use a very limited allocate-only
 136 * heap for new and altered environment variables.  The entire
 137 * environment is limited to a fixed number of entries (add more
 138 * to __env[] if required) and a fixed amount of heap (add more to
 139 * KDB_ENVBUFSIZE if required).
 140 */
 141
 142static char *__env[31] = {
 143#if defined(CONFIG_SMP)
 144	"PROMPT=[%d]kdb> ",
 145#else
 146	"PROMPT=kdb> ",
 147#endif
 148	"MOREPROMPT=more> ",
 149	"RADIX=16",
 150	"MDCOUNT=8",		/* lines of md output */
 151	KDB_PLATFORM_ENV,
 152	"DTABCOUNT=30",
 153	"NOSECT=1",
 154};
 155
 156static const int __nenv = ARRAY_SIZE(__env);
 157
 158struct task_struct *kdb_curr_task(int cpu)
 159{
 160	struct task_struct *p = curr_task(cpu);
 161#ifdef	_TIF_MCA_INIT
 162	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 163		p = krp->p;
 164#endif
 165	return p;
 166}
 167
 168/*
 169 * Update the permissions flags (kdb_cmd_enabled) to match the
 170 * current lockdown state.
 171 *
 172 * Within this function the calls to security_locked_down() are "lazy". We
 173 * avoid calling them if the current value of kdb_cmd_enabled already excludes
 174 * flags that might be subject to lockdown. Additionally we deliberately check
 175 * the lockdown flags independently (even though read lockdown implies write
 176 * lockdown) since that results in both simpler code and clearer messages to
 177 * the user on first-time debugger entry.
 178 *
 179 * The permission masks during a read+write lockdown permits the following
 180 * flags: INSPECT, SIGNAL, REBOOT (and ALWAYS_SAFE).
 181 *
 182 * The INSPECT commands are not blocked during lockdown because they are
 183 * not arbitrary memory reads. INSPECT covers the backtrace family (sometimes
 184 * forcing them to have no arguments) and lsmod. These commands do expose
 185 * some kernel state but do not allow the developer seated at the console to
 186 * choose what state is reported. SIGNAL and REBOOT should not be controversial,
 187 * given these are allowed for root during lockdown already.
 188 */
 189static void kdb_check_for_lockdown(void)
 190{
 191	const int write_flags = KDB_ENABLE_MEM_WRITE |
 192				KDB_ENABLE_REG_WRITE |
 193				KDB_ENABLE_FLOW_CTRL;
 194	const int read_flags = KDB_ENABLE_MEM_READ |
 195			       KDB_ENABLE_REG_READ;
 196
 197	bool need_to_lockdown_write = false;
 198	bool need_to_lockdown_read = false;
 199
 200	if (kdb_cmd_enabled & (KDB_ENABLE_ALL | write_flags))
 201		need_to_lockdown_write =
 202			security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL);
 203
 204	if (kdb_cmd_enabled & (KDB_ENABLE_ALL | read_flags))
 205		need_to_lockdown_read =
 206			security_locked_down(LOCKDOWN_DBG_READ_KERNEL);
 207
 208	/* De-compose KDB_ENABLE_ALL if required */
 209	if (need_to_lockdown_write || need_to_lockdown_read)
 210		if (kdb_cmd_enabled & KDB_ENABLE_ALL)
 211			kdb_cmd_enabled = KDB_ENABLE_MASK & ~KDB_ENABLE_ALL;
 212
 213	if (need_to_lockdown_write)
 214		kdb_cmd_enabled &= ~write_flags;
 215
 216	if (need_to_lockdown_read)
 217		kdb_cmd_enabled &= ~read_flags;
 218}
 219
 220/*
 221 * Check whether the flags of the current command, the permissions of the kdb
 222 * console and the lockdown state allow a command to be run.
 223 */
 224static bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 225				   bool no_args)
 226{
 227	/* permissions comes from userspace so needs massaging slightly */
 228	permissions &= KDB_ENABLE_MASK;
 229	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 230
 231	/* some commands change group when launched with no arguments */
 232	if (no_args)
 233		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 234
 235	flags |= KDB_ENABLE_ALL;
 236
 237	return permissions & flags;
 238}
 239
 240/*
 241 * kdbgetenv - This function will return the character string value of
 242 *	an environment variable.
 243 * Parameters:
 244 *	match	A character string representing an environment variable.
 245 * Returns:
 246 *	NULL	No environment variable matches 'match'
 247 *	char*	Pointer to string value of environment variable.
 248 */
 249char *kdbgetenv(const char *match)
 250{
 251	char **ep = __env;
 252	int matchlen = strlen(match);
 253	int i;
 254
 255	for (i = 0; i < __nenv; i++) {
 256		char *e = *ep++;
 257
 258		if (!e)
 259			continue;
 260
 261		if ((strncmp(match, e, matchlen) == 0)
 262		 && ((e[matchlen] == '\0')
 263		   || (e[matchlen] == '='))) {
 264			char *cp = strchr(e, '=');
 265			return cp ? ++cp : "";
 266		}
 267	}
 268	return NULL;
 269}
 270
 271/*
 272 * kdballocenv - This function is used to allocate bytes for
 273 *	environment entries.
 274 * Parameters:
 275 *	match	A character string representing a numeric value
 276 * Outputs:
 277 *	*value  the unsigned long representation of the env variable 'match'
 278 * Returns:
 279 *	Zero on success, a kdb diagnostic on failure.
 280 * Remarks:
 281 *	We use a static environment buffer (envbuffer) to hold the values
 282 *	of dynamically generated environment variables (see kdb_set).  Buffer
 283 *	space once allocated is never free'd, so over time, the amount of space
 284 *	(currently 512 bytes) will be exhausted if env variables are changed
 285 *	frequently.
 286 */
 287static char *kdballocenv(size_t bytes)
 288{
 289#define	KDB_ENVBUFSIZE	512
 290	static char envbuffer[KDB_ENVBUFSIZE];
 291	static int envbufsize;
 292	char *ep = NULL;
 293
 294	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 295		ep = &envbuffer[envbufsize];
 296		envbufsize += bytes;
 297	}
 298	return ep;
 299}
 300
 301/*
 302 * kdbgetulenv - This function will return the value of an unsigned
 303 *	long-valued environment variable.
 304 * Parameters:
 305 *	match	A character string representing a numeric value
 306 * Outputs:
 307 *	*value  the unsigned long representation of the env variable 'match'
 308 * Returns:
 309 *	Zero on success, a kdb diagnostic on failure.
 310 */
 311static int kdbgetulenv(const char *match, unsigned long *value)
 312{
 313	char *ep;
 314
 315	ep = kdbgetenv(match);
 316	if (!ep)
 317		return KDB_NOTENV;
 318	if (strlen(ep) == 0)
 319		return KDB_NOENVVALUE;
 320
 321	*value = simple_strtoul(ep, NULL, 0);
 322
 323	return 0;
 324}
 325
 326/*
 327 * kdbgetintenv - This function will return the value of an
 328 *	integer-valued environment variable.
 329 * Parameters:
 330 *	match	A character string representing an integer-valued env variable
 331 * Outputs:
 332 *	*value  the integer representation of the environment variable 'match'
 333 * Returns:
 334 *	Zero on success, a kdb diagnostic on failure.
 335 */
 336int kdbgetintenv(const char *match, int *value)
 337{
 338	unsigned long val;
 339	int diag;
 340
 341	diag = kdbgetulenv(match, &val);
 342	if (!diag)
 343		*value = (int) val;
 344	return diag;
 345}
 346
 347/*
 348 * kdb_setenv() - Alter an existing environment variable or create a new one.
 349 * @var: Name of the variable
 350 * @val: Value of the variable
 351 *
 352 * Return: Zero on success, a kdb diagnostic on failure.
 353 */
 354static int kdb_setenv(const char *var, const char *val)
 355{
 356	int i;
 357	char *ep;
 358	size_t varlen, vallen;
 359
 360	varlen = strlen(var);
 361	vallen = strlen(val);
 362	ep = kdballocenv(varlen + vallen + 2);
 363	if (ep == (char *)0)
 364		return KDB_ENVBUFFULL;
 365
 366	sprintf(ep, "%s=%s", var, val);
 367
 368	for (i = 0; i < __nenv; i++) {
 369		if (__env[i]
 370		 && ((strncmp(__env[i], var, varlen) == 0)
 371		   && ((__env[i][varlen] == '\0')
 372		    || (__env[i][varlen] == '=')))) {
 373			__env[i] = ep;
 374			return 0;
 375		}
 376	}
 377
 378	/*
 379	 * Wasn't existing variable.  Fit into slot.
 380	 */
 381	for (i = 0; i < __nenv-1; i++) {
 382		if (__env[i] == (char *)0) {
 383			__env[i] = ep;
 384			return 0;
 385		}
 386	}
 387
 388	return KDB_ENVFULL;
 389}
 390
 391/*
 392 * kdb_printenv() - Display the current environment variables.
 393 */
 394static void kdb_printenv(void)
 395{
 396	int i;
 397
 398	for (i = 0; i < __nenv; i++) {
 399		if (__env[i])
 400			kdb_printf("%s\n", __env[i]);
 401	}
 402}
 403
 404/*
 405 * kdbgetularg - This function will convert a numeric string into an
 406 *	unsigned long value.
 407 * Parameters:
 408 *	arg	A character string representing a numeric value
 409 * Outputs:
 410 *	*value  the unsigned long representation of arg.
 411 * Returns:
 412 *	Zero on success, a kdb diagnostic on failure.
 413 */
 414int kdbgetularg(const char *arg, unsigned long *value)
 415{
 416	char *endp;
 417	unsigned long val;
 418
 419	val = simple_strtoul(arg, &endp, 0);
 420
 421	if (endp == arg) {
 422		/*
 423		 * Also try base 16, for us folks too lazy to type the
 424		 * leading 0x...
 425		 */
 426		val = simple_strtoul(arg, &endp, 16);
 427		if (endp == arg)
 428			return KDB_BADINT;
 429	}
 430
 431	*value = val;
 432
 433	return 0;
 434}
 435
 436int kdbgetu64arg(const char *arg, u64 *value)
 437{
 438	char *endp;
 439	u64 val;
 440
 441	val = simple_strtoull(arg, &endp, 0);
 442
 443	if (endp == arg) {
 444
 445		val = simple_strtoull(arg, &endp, 16);
 446		if (endp == arg)
 447			return KDB_BADINT;
 448	}
 449
 450	*value = val;
 451
 452	return 0;
 453}
 454
 455/*
 456 * kdb_set - This function implements the 'set' command.  Alter an
 457 *	existing environment variable or create a new one.
 458 */
 459int kdb_set(int argc, const char **argv)
 460{
 461	/*
 462	 * we can be invoked two ways:
 463	 *   set var=value    argv[1]="var", argv[2]="value"
 464	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 465	 * - if the latter, shift 'em down.
 466	 */
 467	if (argc == 3) {
 468		argv[2] = argv[3];
 469		argc--;
 470	}
 471
 472	if (argc != 2)
 473		return KDB_ARGCOUNT;
 474
 475	/*
 476	 * Censor sensitive variables
 477	 */
 478	if (strcmp(argv[1], "PROMPT") == 0 &&
 479	    !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
 480		return KDB_NOPERM;
 481
 482	/*
 483	 * Check for internal variables
 484	 */
 485	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 486		unsigned int debugflags;
 487		char *cp;
 488
 489		debugflags = simple_strtoul(argv[2], &cp, 0);
 490		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 491			kdb_printf("kdb: illegal debug flags '%s'\n",
 492				    argv[2]);
 493			return 0;
 494		}
 495		kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
 496			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 497
 498		return 0;
 499	}
 500
 501	/*
 502	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 503	 * name, argv[2] = value.
 504	 */
 505	return kdb_setenv(argv[1], argv[2]);
 506}
 507
 508static int kdb_check_regs(void)
 509{
 510	if (!kdb_current_regs) {
 511		kdb_printf("No current kdb registers."
 512			   "  You may need to select another task\n");
 513		return KDB_BADREG;
 514	}
 515	return 0;
 516}
 517
 518/*
 519 * kdbgetaddrarg - This function is responsible for parsing an
 520 *	address-expression and returning the value of the expression,
 521 *	symbol name, and offset to the caller.
 522 *
 523 *	The argument may consist of a numeric value (decimal or
 524 *	hexadecimal), a symbol name, a register name (preceded by the
 525 *	percent sign), an environment variable with a numeric value
 526 *	(preceded by a dollar sign) or a simple arithmetic expression
 527 *	consisting of a symbol name, +/-, and a numeric constant value
 528 *	(offset).
 529 * Parameters:
 530 *	argc	- count of arguments in argv
 531 *	argv	- argument vector
 532 *	*nextarg - index to next unparsed argument in argv[]
 533 *	regs	- Register state at time of KDB entry
 534 * Outputs:
 535 *	*value	- receives the value of the address-expression
 536 *	*offset - receives the offset specified, if any
 537 *	*name   - receives the symbol name, if any
 538 *	*nextarg - index to next unparsed argument in argv[]
 539 * Returns:
 540 *	zero is returned on success, a kdb diagnostic code is
 541 *      returned on error.
 542 */
 543int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 544		  unsigned long *value,  long *offset,
 545		  char **name)
 546{
 547	unsigned long addr;
 548	unsigned long off = 0;
 549	int positive;
 550	int diag;
 551	int found = 0;
 552	char *symname;
 553	char symbol = '\0';
 554	char *cp;
 555	kdb_symtab_t symtab;
 556
 557	/*
 558	 * If the enable flags prohibit both arbitrary memory access
 559	 * and flow control then there are no reasonable grounds to
 560	 * provide symbol lookup.
 561	 */
 562	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 563			     kdb_cmd_enabled, false))
 564		return KDB_NOPERM;
 565
 566	/*
 567	 * Process arguments which follow the following syntax:
 568	 *
 569	 *  symbol | numeric-address [+/- numeric-offset]
 570	 *  %register
 571	 *  $environment-variable
 572	 */
 573
 574	if (*nextarg > argc)
 575		return KDB_ARGCOUNT;
 576
 577	symname = (char *)argv[*nextarg];
 578
 579	/*
 580	 * If there is no whitespace between the symbol
 581	 * or address and the '+' or '-' symbols, we
 582	 * remember the character and replace it with a
 583	 * null so the symbol/value can be properly parsed
 584	 */
 585	cp = strpbrk(symname, "+-");
 586	if (cp != NULL) {
 587		symbol = *cp;
 588		*cp++ = '\0';
 589	}
 590
 591	if (symname[0] == '$') {
 592		diag = kdbgetulenv(&symname[1], &addr);
 593		if (diag)
 594			return diag;
 595	} else if (symname[0] == '%') {
 596		diag = kdb_check_regs();
 597		if (diag)
 598			return diag;
 599		/* Implement register values with % at a later time as it is
 600		 * arch optional.
 601		 */
 602		return KDB_NOTIMP;
 603	} else {
 604		found = kdbgetsymval(symname, &symtab);
 605		if (found) {
 606			addr = symtab.sym_start;
 607		} else {
 608			diag = kdbgetularg(argv[*nextarg], &addr);
 609			if (diag)
 610				return diag;
 611		}
 612	}
 613
 614	if (!found)
 615		found = kdbnearsym(addr, &symtab);
 616
 617	(*nextarg)++;
 618
 619	if (name)
 620		*name = symname;
 621	if (value)
 622		*value = addr;
 623	if (offset && name && *name)
 624		*offset = addr - symtab.sym_start;
 625
 626	if ((*nextarg > argc)
 627	 && (symbol == '\0'))
 628		return 0;
 629
 630	/*
 631	 * check for +/- and offset
 632	 */
 633
 634	if (symbol == '\0') {
 635		if ((argv[*nextarg][0] != '+')
 636		 && (argv[*nextarg][0] != '-')) {
 637			/*
 638			 * Not our argument.  Return.
 639			 */
 640			return 0;
 641		} else {
 642			positive = (argv[*nextarg][0] == '+');
 643			(*nextarg)++;
 644		}
 645	} else
 646		positive = (symbol == '+');
 647
 648	/*
 649	 * Now there must be an offset!
 650	 */
 651	if ((*nextarg > argc)
 652	 && (symbol == '\0')) {
 653		return KDB_INVADDRFMT;
 654	}
 655
 656	if (!symbol) {
 657		cp = (char *)argv[*nextarg];
 658		(*nextarg)++;
 659	}
 660
 661	diag = kdbgetularg(cp, &off);
 662	if (diag)
 663		return diag;
 664
 665	if (!positive)
 666		off = -off;
 667
 668	if (offset)
 669		*offset += off;
 670
 671	if (value)
 672		*value += off;
 673
 674	return 0;
 675}
 676
 677static void kdb_cmderror(int diag)
 678{
 679	int i;
 680
 681	if (diag >= 0) {
 682		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 683		return;
 684	}
 685
 686	for (i = 0; i < __nkdb_err; i++) {
 687		if (kdbmsgs[i].km_diag == diag) {
 688			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 689			return;
 690		}
 691	}
 692
 693	kdb_printf("Unknown diag %d\n", -diag);
 694}
 695
 696/*
 697 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 698 *	command which defines one command as a set of other commands,
 699 *	terminated by endefcmd.  kdb_defcmd processes the initial
 700 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 701 *	the following commands until 'endefcmd'.
 702 * Inputs:
 703 *	argc	argument count
 704 *	argv	argument vector
 705 * Returns:
 706 *	zero for success, a kdb diagnostic if error
 707 */
 708struct kdb_macro {
 709	kdbtab_t cmd;			/* Macro command */
 710	struct list_head statements;	/* Associated statement list */
 711};
 712
 713struct kdb_macro_statement {
 714	char *statement;		/* Statement text */
 715	struct list_head list_node;	/* Statement list node */
 716};
 717
 718static struct kdb_macro *kdb_macro;
 719static bool defcmd_in_progress;
 720
 721/* Forward references */
 722static int kdb_exec_defcmd(int argc, const char **argv);
 723
 724static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 725{
 726	struct kdb_macro_statement *kms;
 727
 728	if (!kdb_macro)
 729		return KDB_NOTIMP;
 730
 731	if (strcmp(argv0, "endefcmd") == 0) {
 732		defcmd_in_progress = false;
 733		if (!list_empty(&kdb_macro->statements))
 734			kdb_register(&kdb_macro->cmd);
 
 
 
 
 
 
 
 
 735		return 0;
 736	}
 737
 738	kms = kmalloc(sizeof(*kms), GFP_KDB);
 739	if (!kms) {
 740		kdb_printf("Could not allocate new kdb macro command: %s\n",
 
 741			   cmdstr);
 
 742		return KDB_NOTIMP;
 743	}
 744
 745	kms->statement = kdb_strdup(cmdstr, GFP_KDB);
 746	list_add_tail(&kms->list_node, &kdb_macro->statements);
 747
 748	return 0;
 749}
 750
 751static int kdb_defcmd(int argc, const char **argv)
 752{
 753	kdbtab_t *mp;
 754
 755	if (defcmd_in_progress) {
 756		kdb_printf("kdb: nested defcmd detected, assuming missing "
 757			   "endefcmd\n");
 758		kdb_defcmd2("endefcmd", "endefcmd");
 759	}
 760	if (argc == 0) {
 761		kdbtab_t *kp;
 762		struct kdb_macro *kmp;
 763		struct kdb_macro_statement *kms;
 764
 765		list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 766			if (kp->func == kdb_exec_defcmd) {
 767				kdb_printf("defcmd %s \"%s\" \"%s\"\n",
 768					   kp->name, kp->usage, kp->help);
 769				kmp = container_of(kp, struct kdb_macro, cmd);
 770				list_for_each_entry(kms, &kmp->statements,
 771						    list_node)
 772					kdb_printf("%s", kms->statement);
 773				kdb_printf("endefcmd\n");
 774			}
 775		}
 776		return 0;
 777	}
 778	if (argc != 3)
 779		return KDB_ARGCOUNT;
 780	if (in_dbg_master()) {
 781		kdb_printf("Command only available during kdb_init()\n");
 782		return KDB_NOTIMP;
 783	}
 784	kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);
 785	if (!kdb_macro)
 
 786		goto fail_defcmd;
 787
 788	mp = &kdb_macro->cmd;
 789	mp->func = kdb_exec_defcmd;
 790	mp->minlen = 0;
 791	mp->flags = KDB_ENABLE_ALWAYS_SAFE;
 792	mp->name = kdb_strdup(argv[1], GFP_KDB);
 793	if (!mp->name)
 794		goto fail_name;
 795	mp->usage = kdb_strdup(argv[2], GFP_KDB);
 796	if (!mp->usage)
 797		goto fail_usage;
 798	mp->help = kdb_strdup(argv[3], GFP_KDB);
 799	if (!mp->help)
 800		goto fail_help;
 801	if (mp->usage[0] == '"') {
 802		strcpy(mp->usage, argv[2]+1);
 803		mp->usage[strlen(mp->usage)-1] = '\0';
 
 
 
 
 804	}
 805	if (mp->help[0] == '"') {
 806		strcpy(mp->help, argv[3]+1);
 807		mp->help[strlen(mp->help)-1] = '\0';
 808	}
 809
 810	INIT_LIST_HEAD(&kdb_macro->statements);
 811	defcmd_in_progress = true;
 
 812	return 0;
 813fail_help:
 814	kfree(mp->usage);
 815fail_usage:
 816	kfree(mp->name);
 817fail_name:
 818	kfree(kdb_macro);
 819fail_defcmd:
 820	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
 
 821	return KDB_NOTIMP;
 822}
 823
 824/*
 825 * kdb_exec_defcmd - Execute the set of commands associated with this
 826 *	defcmd name.
 827 * Inputs:
 828 *	argc	argument count
 829 *	argv	argument vector
 830 * Returns:
 831 *	zero for success, a kdb diagnostic if error
 832 */
 833static int kdb_exec_defcmd(int argc, const char **argv)
 834{
 835	int ret;
 836	kdbtab_t *kp;
 837	struct kdb_macro *kmp;
 838	struct kdb_macro_statement *kms;
 839
 840	if (argc != 0)
 841		return KDB_ARGCOUNT;
 842
 843	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 844		if (strcmp(kp->name, argv[0]) == 0)
 845			break;
 846	}
 847	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
 848		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 849			   argv[0]);
 850		return KDB_NOTIMP;
 851	}
 852	kmp = container_of(kp, struct kdb_macro, cmd);
 853	list_for_each_entry(kms, &kmp->statements, list_node) {
 854		/*
 855		 * Recursive use of kdb_parse, do not use argv after this point.
 856		 */
 857		argv = NULL;
 858		kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement);
 859		ret = kdb_parse(kms->statement);
 860		if (ret)
 861			return ret;
 862	}
 863	return 0;
 864}
 865
 866/* Command history */
 867#define KDB_CMD_HISTORY_COUNT	32
 868#define CMD_BUFLEN		200	/* kdb_printf: max printline
 869					 * size == 256 */
 870static unsigned int cmd_head, cmd_tail;
 871static unsigned int cmdptr;
 872static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 873static char cmd_cur[CMD_BUFLEN];
 874
 875/*
 876 * The "str" argument may point to something like  | grep xyz
 877 */
 878static void parse_grep(const char *str)
 879{
 880	int	len;
 881	char	*cp = (char *)str, *cp2;
 882
 883	/* sanity check: we should have been called with the \ first */
 884	if (*cp != '|')
 885		return;
 886	cp++;
 887	while (isspace(*cp))
 888		cp++;
 889	if (!str_has_prefix(cp, "grep ")) {
 890		kdb_printf("invalid 'pipe', see grephelp\n");
 891		return;
 892	}
 893	cp += 5;
 894	while (isspace(*cp))
 895		cp++;
 896	cp2 = strchr(cp, '\n');
 897	if (cp2)
 898		*cp2 = '\0'; /* remove the trailing newline */
 899	len = strlen(cp);
 900	if (len == 0) {
 901		kdb_printf("invalid 'pipe', see grephelp\n");
 902		return;
 903	}
 904	/* now cp points to a nonzero length search string */
 905	if (*cp == '"') {
 906		/* allow it be "x y z" by removing the "'s - there must
 907		   be two of them */
 908		cp++;
 909		cp2 = strchr(cp, '"');
 910		if (!cp2) {
 911			kdb_printf("invalid quoted string, see grephelp\n");
 912			return;
 913		}
 914		*cp2 = '\0'; /* end the string where the 2nd " was */
 915	}
 916	kdb_grep_leading = 0;
 917	if (*cp == '^') {
 918		kdb_grep_leading = 1;
 919		cp++;
 920	}
 921	len = strlen(cp);
 922	kdb_grep_trailing = 0;
 923	if (*(cp+len-1) == '$') {
 924		kdb_grep_trailing = 1;
 925		*(cp+len-1) = '\0';
 926	}
 927	len = strlen(cp);
 928	if (!len)
 929		return;
 930	if (len >= KDB_GREP_STRLEN) {
 931		kdb_printf("search string too long\n");
 932		return;
 933	}
 934	strcpy(kdb_grep_string, cp);
 935	kdb_grepping_flag++;
 936	return;
 937}
 938
 939/*
 940 * kdb_parse - Parse the command line, search the command table for a
 941 *	matching command and invoke the command function.  This
 942 *	function may be called recursively, if it is, the second call
 943 *	will overwrite argv and cbuf.  It is the caller's
 944 *	responsibility to save their argv if they recursively call
 945 *	kdb_parse().
 946 * Parameters:
 947 *      cmdstr	The input command line to be parsed.
 948 *	regs	The registers at the time kdb was entered.
 949 * Returns:
 950 *	Zero for success, a kdb diagnostic if failure.
 951 * Remarks:
 952 *	Limited to 20 tokens.
 953 *
 954 *	Real rudimentary tokenization. Basically only whitespace
 955 *	is considered a token delimiter (but special consideration
 956 *	is taken of the '=' sign as used by the 'set' command).
 957 *
 958 *	The algorithm used to tokenize the input string relies on
 959 *	there being at least one whitespace (or otherwise useless)
 960 *	character between tokens as the character immediately following
 961 *	the token is altered in-place to a null-byte to terminate the
 962 *	token string.
 963 */
 964
 965#define MAXARGC	20
 966
 967int kdb_parse(const char *cmdstr)
 968{
 969	static char *argv[MAXARGC];
 970	static int argc;
 971	static char cbuf[CMD_BUFLEN+2];
 972	char *cp;
 973	char *cpp, quoted;
 974	kdbtab_t *tp;
 975	int escaped, ignore_errors = 0, check_grep = 0;
 976
 977	/*
 978	 * First tokenize the command string.
 979	 */
 980	cp = (char *)cmdstr;
 981
 982	if (KDB_FLAG(CMD_INTERRUPT)) {
 983		/* Previous command was interrupted, newline must not
 984		 * repeat the command */
 985		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 986		KDB_STATE_SET(PAGER);
 987		argc = 0;	/* no repeat */
 988	}
 989
 990	if (*cp != '\n' && *cp != '\0') {
 991		argc = 0;
 992		cpp = cbuf;
 993		while (*cp) {
 994			/* skip whitespace */
 995			while (isspace(*cp))
 996				cp++;
 997			if ((*cp == '\0') || (*cp == '\n') ||
 998			    (*cp == '#' && !defcmd_in_progress))
 999				break;
1000			/* special case: check for | grep pattern */
1001			if (*cp == '|') {
1002				check_grep++;
1003				break;
1004			}
1005			if (cpp >= cbuf + CMD_BUFLEN) {
1006				kdb_printf("kdb_parse: command buffer "
1007					   "overflow, command ignored\n%s\n",
1008					   cmdstr);
1009				return KDB_NOTFOUND;
1010			}
1011			if (argc >= MAXARGC - 1) {
1012				kdb_printf("kdb_parse: too many arguments, "
1013					   "command ignored\n%s\n", cmdstr);
1014				return KDB_NOTFOUND;
1015			}
1016			argv[argc++] = cpp;
1017			escaped = 0;
1018			quoted = '\0';
1019			/* Copy to next unquoted and unescaped
1020			 * whitespace or '=' */
1021			while (*cp && *cp != '\n' &&
1022			       (escaped || quoted || !isspace(*cp))) {
1023				if (cpp >= cbuf + CMD_BUFLEN)
1024					break;
1025				if (escaped) {
1026					escaped = 0;
1027					*cpp++ = *cp++;
1028					continue;
1029				}
1030				if (*cp == '\\') {
1031					escaped = 1;
1032					++cp;
1033					continue;
1034				}
1035				if (*cp == quoted)
1036					quoted = '\0';
1037				else if (*cp == '\'' || *cp == '"')
1038					quoted = *cp;
1039				*cpp = *cp++;
1040				if (*cpp == '=' && !quoted)
1041					break;
1042				++cpp;
1043			}
1044			*cpp++ = '\0';	/* Squash a ws or '=' character */
1045		}
1046	}
1047	if (!argc)
1048		return 0;
1049	if (check_grep)
1050		parse_grep(cp);
1051	if (defcmd_in_progress) {
1052		int result = kdb_defcmd2(cmdstr, argv[0]);
1053		if (!defcmd_in_progress) {
1054			argc = 0;	/* avoid repeat on endefcmd */
1055			*(argv[0]) = '\0';
1056		}
1057		return result;
1058	}
1059	if (argv[0][0] == '-' && argv[0][1] &&
1060	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1061		ignore_errors = 1;
1062		++argv[0];
1063	}
1064
1065	list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1066		/*
1067		 * If this command is allowed to be abbreviated,
1068		 * check to see if this is it.
1069		 */
1070		if (tp->minlen && (strlen(argv[0]) <= tp->minlen) &&
1071		    (strncmp(argv[0], tp->name, tp->minlen) == 0))
1072			break;
1073
1074		if (strcmp(argv[0], tp->name) == 0)
1075			break;
1076	}
1077
1078	/*
1079	 * If we don't find a command by this name, see if the first
1080	 * few characters of this match any of the known commands.
1081	 * e.g., md1c20 should match md.
1082	 */
1083	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1084		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1085			if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0)
 
1086				break;
1087		}
1088	}
1089
1090	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1091		int result;
1092
1093		if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1))
1094			return KDB_NOPERM;
1095
1096		KDB_STATE_SET(CMD);
1097		result = (*tp->func)(argc-1, (const char **)argv);
1098		if (result && ignore_errors && result > KDB_CMD_GO)
1099			result = 0;
1100		KDB_STATE_CLEAR(CMD);
1101
1102		if (tp->flags & KDB_REPEAT_WITH_ARGS)
1103			return result;
1104
1105		argc = tp->flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1106		if (argv[argc])
1107			*(argv[argc]) = '\0';
1108		return result;
1109	}
1110
1111	/*
1112	 * If the input with which we were presented does not
1113	 * map to an existing command, attempt to parse it as an
1114	 * address argument and display the result.   Useful for
1115	 * obtaining the address of a variable, or the nearest symbol
1116	 * to an address contained in a register.
1117	 */
1118	{
1119		unsigned long value;
1120		char *name = NULL;
1121		long offset;
1122		int nextarg = 0;
1123
1124		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1125				  &value, &offset, &name)) {
1126			return KDB_NOTFOUND;
1127		}
1128
1129		kdb_printf("%s = ", argv[0]);
1130		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1131		kdb_printf("\n");
1132		return 0;
1133	}
1134}
1135
1136
1137static int handle_ctrl_cmd(char *cmd)
1138{
1139#define CTRL_P	16
1140#define CTRL_N	14
1141
1142	/* initial situation */
1143	if (cmd_head == cmd_tail)
1144		return 0;
1145	switch (*cmd) {
1146	case CTRL_P:
1147		if (cmdptr != cmd_tail)
1148			cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) %
1149				 KDB_CMD_HISTORY_COUNT;
1150		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1151		return 1;
1152	case CTRL_N:
1153		if (cmdptr != cmd_head)
1154			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1155		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1156		return 1;
1157	}
1158	return 0;
1159}
1160
1161/*
1162 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1163 *	the system immediately, or loop for ever on failure.
1164 */
1165static int kdb_reboot(int argc, const char **argv)
1166{
1167	emergency_restart();
1168	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1169	while (1)
1170		cpu_relax();
1171	/* NOTREACHED */
1172	return 0;
1173}
1174
1175static void kdb_dumpregs(struct pt_regs *regs)
1176{
1177	int old_lvl = console_loglevel;
1178	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1179	kdb_trap_printk++;
1180	show_regs(regs);
1181	kdb_trap_printk--;
1182	kdb_printf("\n");
1183	console_loglevel = old_lvl;
1184}
1185
1186static void kdb_set_current_task(struct task_struct *p)
1187{
1188	kdb_current_task = p;
1189
1190	if (kdb_task_has_cpu(p)) {
1191		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1192		return;
1193	}
1194	kdb_current_regs = NULL;
1195}
1196
1197static void drop_newline(char *buf)
1198{
1199	size_t len = strlen(buf);
1200
1201	if (len == 0)
1202		return;
1203	if (*(buf + len - 1) == '\n')
1204		*(buf + len - 1) = '\0';
1205}
1206
1207/*
1208 * kdb_local - The main code for kdb.  This routine is invoked on a
1209 *	specific processor, it is not global.  The main kdb() routine
1210 *	ensures that only one processor at a time is in this routine.
1211 *	This code is called with the real reason code on the first
1212 *	entry to a kdb session, thereafter it is called with reason
1213 *	SWITCH, even if the user goes back to the original cpu.
1214 * Inputs:
1215 *	reason		The reason KDB was invoked
1216 *	error		The hardware-defined error code
1217 *	regs		The exception frame at time of fault/breakpoint.
1218 *	db_result	Result code from the break or debug point.
1219 * Returns:
1220 *	0	KDB was invoked for an event which it wasn't responsible
1221 *	1	KDB handled the event for which it was invoked.
1222 *	KDB_CMD_GO	User typed 'go'.
1223 *	KDB_CMD_CPU	User switched to another cpu.
1224 *	KDB_CMD_SS	Single step.
1225 */
1226static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1227		     kdb_dbtrap_t db_result)
1228{
1229	char *cmdbuf;
1230	int diag;
1231	struct task_struct *kdb_current =
1232		kdb_curr_task(raw_smp_processor_id());
1233
1234	KDB_DEBUG_STATE("kdb_local 1", reason);
1235
1236	kdb_check_for_lockdown();
1237
1238	kdb_go_count = 0;
1239	if (reason == KDB_REASON_DEBUG) {
1240		/* special case below */
1241	} else {
1242		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1243			   kdb_current, kdb_current ? kdb_current->pid : 0);
1244#if defined(CONFIG_SMP)
1245		kdb_printf("on processor %d ", raw_smp_processor_id());
1246#endif
1247	}
1248
1249	switch (reason) {
1250	case KDB_REASON_DEBUG:
1251	{
1252		/*
1253		 * If re-entering kdb after a single step
1254		 * command, don't print the message.
1255		 */
1256		switch (db_result) {
1257		case KDB_DB_BPT:
1258			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1259				   kdb_current, kdb_current->pid);
1260#if defined(CONFIG_SMP)
1261			kdb_printf("on processor %d ", raw_smp_processor_id());
1262#endif
1263			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1264				   instruction_pointer(regs));
1265			break;
1266		case KDB_DB_SS:
1267			break;
1268		case KDB_DB_SSBPT:
1269			KDB_DEBUG_STATE("kdb_local 4", reason);
1270			return 1;	/* kdba_db_trap did the work */
1271		default:
1272			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1273				   db_result);
1274			break;
1275		}
1276
1277	}
1278		break;
1279	case KDB_REASON_ENTER:
1280		if (KDB_STATE(KEYBOARD))
1281			kdb_printf("due to Keyboard Entry\n");
1282		else
1283			kdb_printf("due to KDB_ENTER()\n");
1284		break;
1285	case KDB_REASON_KEYBOARD:
1286		KDB_STATE_SET(KEYBOARD);
1287		kdb_printf("due to Keyboard Entry\n");
1288		break;
1289	case KDB_REASON_ENTER_SLAVE:
1290		/* drop through, slaves only get released via cpu switch */
1291	case KDB_REASON_SWITCH:
1292		kdb_printf("due to cpu switch\n");
1293		break;
1294	case KDB_REASON_OOPS:
1295		kdb_printf("Oops: %s\n", kdb_diemsg);
1296		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1297			   instruction_pointer(regs));
1298		kdb_dumpregs(regs);
1299		break;
1300	case KDB_REASON_SYSTEM_NMI:
1301		kdb_printf("due to System NonMaskable Interrupt\n");
1302		break;
1303	case KDB_REASON_NMI:
1304		kdb_printf("due to NonMaskable Interrupt @ "
1305			   kdb_machreg_fmt "\n",
1306			   instruction_pointer(regs));
1307		break;
1308	case KDB_REASON_SSTEP:
1309	case KDB_REASON_BREAK:
1310		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1311			   reason == KDB_REASON_BREAK ?
1312			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1313		/*
1314		 * Determine if this breakpoint is one that we
1315		 * are interested in.
1316		 */
1317		if (db_result != KDB_DB_BPT) {
1318			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1319				   db_result);
1320			KDB_DEBUG_STATE("kdb_local 6", reason);
1321			return 0;	/* Not for us, dismiss it */
1322		}
1323		break;
1324	case KDB_REASON_RECURSE:
1325		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1326			   instruction_pointer(regs));
1327		break;
1328	default:
1329		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1330		KDB_DEBUG_STATE("kdb_local 8", reason);
1331		return 0;	/* Not for us, dismiss it */
1332	}
1333
1334	while (1) {
1335		/*
1336		 * Initialize pager context.
1337		 */
1338		kdb_nextline = 1;
1339		KDB_STATE_CLEAR(SUPPRESS);
1340		kdb_grepping_flag = 0;
1341		/* ensure the old search does not leak into '/' commands */
1342		kdb_grep_string[0] = '\0';
1343
1344		cmdbuf = cmd_cur;
1345		*cmdbuf = '\0';
1346		*(cmd_hist[cmd_head]) = '\0';
1347
1348do_full_getstr:
1349		/* PROMPT can only be set if we have MEM_READ permission. */
1350		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1351			 raw_smp_processor_id());
1352		if (defcmd_in_progress)
1353			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1354
1355		/*
1356		 * Fetch command from keyboard
1357		 */
1358		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1359		if (*cmdbuf != '\n') {
1360			if (*cmdbuf < 32) {
1361				if (cmdptr == cmd_head) {
1362					strscpy(cmd_hist[cmd_head], cmd_cur,
1363						CMD_BUFLEN);
1364					*(cmd_hist[cmd_head] +
1365					  strlen(cmd_hist[cmd_head])-1) = '\0';
1366				}
1367				if (!handle_ctrl_cmd(cmdbuf))
1368					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1369				cmdbuf = cmd_cur;
1370				goto do_full_getstr;
1371			} else {
1372				strscpy(cmd_hist[cmd_head], cmd_cur,
1373					CMD_BUFLEN);
1374			}
1375
1376			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1377			if (cmd_head == cmd_tail)
1378				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1379		}
1380
1381		cmdptr = cmd_head;
1382		diag = kdb_parse(cmdbuf);
1383		if (diag == KDB_NOTFOUND) {
1384			drop_newline(cmdbuf);
1385			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1386			diag = 0;
1387		}
1388		if (diag == KDB_CMD_GO
1389		 || diag == KDB_CMD_CPU
1390		 || diag == KDB_CMD_SS
1391		 || diag == KDB_CMD_KGDB)
1392			break;
1393
1394		if (diag)
1395			kdb_cmderror(diag);
1396	}
1397	KDB_DEBUG_STATE("kdb_local 9", diag);
1398	return diag;
1399}
1400
1401
1402/*
1403 * kdb_print_state - Print the state data for the current processor
1404 *	for debugging.
1405 * Inputs:
1406 *	text		Identifies the debug point
1407 *	value		Any integer value to be printed, e.g. reason code.
1408 */
1409void kdb_print_state(const char *text, int value)
1410{
1411	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1412		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1413		   kdb_state);
1414}
1415
1416/*
1417 * kdb_main_loop - After initial setup and assignment of the
1418 *	controlling cpu, all cpus are in this loop.  One cpu is in
1419 *	control and will issue the kdb prompt, the others will spin
1420 *	until 'go' or cpu switch.
1421 *
1422 *	To get a consistent view of the kernel stacks for all
1423 *	processes, this routine is invoked from the main kdb code via
1424 *	an architecture specific routine.  kdba_main_loop is
1425 *	responsible for making the kernel stacks consistent for all
1426 *	processes, there should be no difference between a blocked
1427 *	process and a running process as far as kdb is concerned.
1428 * Inputs:
1429 *	reason		The reason KDB was invoked
1430 *	error		The hardware-defined error code
1431 *	reason2		kdb's current reason code.
1432 *			Initially error but can change
1433 *			according to kdb state.
1434 *	db_result	Result code from break or debug point.
1435 *	regs		The exception frame at time of fault/breakpoint.
1436 *			should always be valid.
1437 * Returns:
1438 *	0	KDB was invoked for an event which it wasn't responsible
1439 *	1	KDB handled the event for which it was invoked.
1440 */
1441int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1442	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1443{
1444	int result = 1;
1445	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1446	while (1) {
1447		/*
1448		 * All processors except the one that is in control
1449		 * will spin here.
1450		 */
1451		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1452		while (KDB_STATE(HOLD_CPU)) {
1453			/* state KDB is turned off by kdb_cpu to see if the
1454			 * other cpus are still live, each cpu in this loop
1455			 * turns it back on.
1456			 */
1457			if (!KDB_STATE(KDB))
1458				KDB_STATE_SET(KDB);
1459		}
1460
1461		KDB_STATE_CLEAR(SUPPRESS);
1462		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1463		if (KDB_STATE(LEAVING))
1464			break;	/* Another cpu said 'go' */
1465		/* Still using kdb, this processor is in control */
1466		result = kdb_local(reason2, error, regs, db_result);
1467		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1468
1469		if (result == KDB_CMD_CPU)
1470			break;
1471
1472		if (result == KDB_CMD_SS) {
1473			KDB_STATE_SET(DOING_SS);
1474			break;
1475		}
1476
1477		if (result == KDB_CMD_KGDB) {
1478			if (!KDB_STATE(DOING_KGDB))
1479				kdb_printf("Entering please attach debugger "
1480					   "or use $D#44+ or $3#33\n");
1481			break;
1482		}
1483		if (result && result != 1 && result != KDB_CMD_GO)
1484			kdb_printf("\nUnexpected kdb_local return code %d\n",
1485				   result);
1486		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1487		break;
1488	}
1489	if (KDB_STATE(DOING_SS))
1490		KDB_STATE_CLEAR(SSBPT);
1491
1492	/* Clean up any keyboard devices before leaving */
1493	kdb_kbd_cleanup_state();
1494
1495	return result;
1496}
1497
1498/*
1499 * kdb_mdr - This function implements the guts of the 'mdr', memory
1500 * read command.
1501 *	mdr  <addr arg>,<byte count>
1502 * Inputs:
1503 *	addr	Start address
1504 *	count	Number of bytes
1505 * Returns:
1506 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1507 */
1508static int kdb_mdr(unsigned long addr, unsigned int count)
1509{
1510	unsigned char c;
1511	while (count--) {
1512		if (kdb_getarea(c, addr))
1513			return 0;
1514		kdb_printf("%02x", c);
1515		addr++;
1516	}
1517	kdb_printf("\n");
1518	return 0;
1519}
1520
1521/*
1522 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1523 *	'md8' 'mdr' and 'mds' commands.
1524 *
1525 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1526 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1527 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1528 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1529 *	mdr  <addr arg>,<byte count>
1530 */
1531static void kdb_md_line(const char *fmtstr, unsigned long addr,
1532			int symbolic, int nosect, int bytesperword,
1533			int num, int repeat, int phys)
1534{
1535	/* print just one line of data */
1536	kdb_symtab_t symtab;
1537	char cbuf[32];
1538	char *c = cbuf;
1539	int i;
1540	int j;
1541	unsigned long word;
1542
1543	memset(cbuf, '\0', sizeof(cbuf));
1544	if (phys)
1545		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1546	else
1547		kdb_printf(kdb_machreg_fmt0 " ", addr);
1548
1549	for (i = 0; i < num && repeat--; i++) {
1550		if (phys) {
1551			if (kdb_getphysword(&word, addr, bytesperword))
1552				break;
1553		} else if (kdb_getword(&word, addr, bytesperword))
1554			break;
1555		kdb_printf(fmtstr, word);
1556		if (symbolic)
1557			kdbnearsym(word, &symtab);
1558		else
1559			memset(&symtab, 0, sizeof(symtab));
1560		if (symtab.sym_name) {
1561			kdb_symbol_print(word, &symtab, 0);
1562			if (!nosect) {
1563				kdb_printf("\n");
1564				kdb_printf("                       %s %s "
1565					   kdb_machreg_fmt " "
1566					   kdb_machreg_fmt " "
1567					   kdb_machreg_fmt, symtab.mod_name,
1568					   symtab.sec_name, symtab.sec_start,
1569					   symtab.sym_start, symtab.sym_end);
1570			}
1571			addr += bytesperword;
1572		} else {
1573			union {
1574				u64 word;
1575				unsigned char c[8];
1576			} wc;
1577			unsigned char *cp;
1578#ifdef	__BIG_ENDIAN
1579			cp = wc.c + 8 - bytesperword;
1580#else
1581			cp = wc.c;
1582#endif
1583			wc.word = word;
1584#define printable_char(c) \
1585	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1586			for (j = 0; j < bytesperword; j++)
1587				*c++ = printable_char(*cp++);
1588			addr += bytesperword;
1589#undef printable_char
1590		}
1591	}
1592	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1593		   " ", cbuf);
1594}
1595
1596static int kdb_md(int argc, const char **argv)
1597{
1598	static unsigned long last_addr;
1599	static int last_radix, last_bytesperword, last_repeat;
1600	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1601	int nosect = 0;
1602	char fmtchar, fmtstr[64];
1603	unsigned long addr;
1604	unsigned long word;
1605	long offset = 0;
1606	int symbolic = 0;
1607	int valid = 0;
1608	int phys = 0;
1609	int raw = 0;
1610
1611	kdbgetintenv("MDCOUNT", &mdcount);
1612	kdbgetintenv("RADIX", &radix);
1613	kdbgetintenv("BYTESPERWORD", &bytesperword);
1614
1615	/* Assume 'md <addr>' and start with environment values */
1616	repeat = mdcount * 16 / bytesperword;
1617
1618	if (strcmp(argv[0], "mdr") == 0) {
1619		if (argc == 2 || (argc == 0 && last_addr != 0))
1620			valid = raw = 1;
1621		else
1622			return KDB_ARGCOUNT;
1623	} else if (isdigit(argv[0][2])) {
1624		bytesperword = (int)(argv[0][2] - '0');
1625		if (bytesperword == 0) {
1626			bytesperword = last_bytesperword;
1627			if (bytesperword == 0)
1628				bytesperword = 4;
1629		}
1630		last_bytesperword = bytesperword;
1631		repeat = mdcount * 16 / bytesperword;
1632		if (!argv[0][3])
1633			valid = 1;
1634		else if (argv[0][3] == 'c' && argv[0][4]) {
1635			char *p;
1636			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1637			mdcount = ((repeat * bytesperword) + 15) / 16;
1638			valid = !*p;
1639		}
1640		last_repeat = repeat;
1641	} else if (strcmp(argv[0], "md") == 0)
1642		valid = 1;
1643	else if (strcmp(argv[0], "mds") == 0)
1644		valid = 1;
1645	else if (strcmp(argv[0], "mdp") == 0) {
1646		phys = valid = 1;
1647	}
1648	if (!valid)
1649		return KDB_NOTFOUND;
1650
1651	if (argc == 0) {
1652		if (last_addr == 0)
1653			return KDB_ARGCOUNT;
1654		addr = last_addr;
1655		radix = last_radix;
1656		bytesperword = last_bytesperword;
1657		repeat = last_repeat;
1658		if (raw)
1659			mdcount = repeat;
1660		else
1661			mdcount = ((repeat * bytesperword) + 15) / 16;
1662	}
1663
1664	if (argc) {
1665		unsigned long val;
1666		int diag, nextarg = 1;
1667		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1668				     &offset, NULL);
1669		if (diag)
1670			return diag;
1671		if (argc > nextarg+2)
1672			return KDB_ARGCOUNT;
1673
1674		if (argc >= nextarg) {
1675			diag = kdbgetularg(argv[nextarg], &val);
1676			if (!diag) {
1677				mdcount = (int) val;
1678				if (raw)
1679					repeat = mdcount;
1680				else
1681					repeat = mdcount * 16 / bytesperword;
1682			}
1683		}
1684		if (argc >= nextarg+1) {
1685			diag = kdbgetularg(argv[nextarg+1], &val);
1686			if (!diag)
1687				radix = (int) val;
1688		}
1689	}
1690
1691	if (strcmp(argv[0], "mdr") == 0) {
1692		int ret;
1693		last_addr = addr;
1694		ret = kdb_mdr(addr, mdcount);
1695		last_addr += mdcount;
1696		last_repeat = mdcount;
1697		last_bytesperword = bytesperword; // to make REPEAT happy
1698		return ret;
1699	}
1700
1701	switch (radix) {
1702	case 10:
1703		fmtchar = 'd';
1704		break;
1705	case 16:
1706		fmtchar = 'x';
1707		break;
1708	case 8:
1709		fmtchar = 'o';
1710		break;
1711	default:
1712		return KDB_BADRADIX;
1713	}
1714
1715	last_radix = radix;
1716
1717	if (bytesperword > KDB_WORD_SIZE)
1718		return KDB_BADWIDTH;
1719
1720	switch (bytesperword) {
1721	case 8:
1722		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1723		break;
1724	case 4:
1725		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1726		break;
1727	case 2:
1728		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1729		break;
1730	case 1:
1731		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1732		break;
1733	default:
1734		return KDB_BADWIDTH;
1735	}
1736
1737	last_repeat = repeat;
1738	last_bytesperword = bytesperword;
1739
1740	if (strcmp(argv[0], "mds") == 0) {
1741		symbolic = 1;
1742		/* Do not save these changes as last_*, they are temporary mds
1743		 * overrides.
1744		 */
1745		bytesperword = KDB_WORD_SIZE;
1746		repeat = mdcount;
1747		kdbgetintenv("NOSECT", &nosect);
1748	}
1749
1750	/* Round address down modulo BYTESPERWORD */
1751
1752	addr &= ~(bytesperword-1);
1753
1754	while (repeat > 0) {
1755		unsigned long a;
1756		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1757
1758		if (KDB_FLAG(CMD_INTERRUPT))
1759			return 0;
1760		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1761			if (phys) {
1762				if (kdb_getphysword(&word, a, bytesperword)
1763						|| word)
1764					break;
1765			} else if (kdb_getword(&word, a, bytesperword) || word)
1766				break;
1767		}
1768		n = min(num, repeat);
1769		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1770			    num, repeat, phys);
1771		addr += bytesperword * n;
1772		repeat -= n;
1773		z = (z + num - 1) / num;
1774		if (z > 2) {
1775			int s = num * (z-2);
1776			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1777				   " zero suppressed\n",
1778				addr, addr + bytesperword * s - 1);
1779			addr += bytesperword * s;
1780			repeat -= s;
1781		}
1782	}
1783	last_addr = addr;
1784
1785	return 0;
1786}
1787
1788/*
1789 * kdb_mm - This function implements the 'mm' command.
1790 *	mm address-expression new-value
1791 * Remarks:
1792 *	mm works on machine words, mmW works on bytes.
1793 */
1794static int kdb_mm(int argc, const char **argv)
1795{
1796	int diag;
1797	unsigned long addr;
1798	long offset = 0;
1799	unsigned long contents;
1800	int nextarg;
1801	int width;
1802
1803	if (argv[0][2] && !isdigit(argv[0][2]))
1804		return KDB_NOTFOUND;
1805
1806	if (argc < 2)
1807		return KDB_ARGCOUNT;
1808
1809	nextarg = 1;
1810	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1811	if (diag)
1812		return diag;
1813
1814	if (nextarg > argc)
1815		return KDB_ARGCOUNT;
1816	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1817	if (diag)
1818		return diag;
1819
1820	if (nextarg != argc + 1)
1821		return KDB_ARGCOUNT;
1822
1823	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1824	diag = kdb_putword(addr, contents, width);
1825	if (diag)
1826		return diag;
1827
1828	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1829
1830	return 0;
1831}
1832
1833/*
1834 * kdb_go - This function implements the 'go' command.
1835 *	go [address-expression]
1836 */
1837static int kdb_go(int argc, const char **argv)
1838{
1839	unsigned long addr;
1840	int diag;
1841	int nextarg;
1842	long offset;
1843
1844	if (raw_smp_processor_id() != kdb_initial_cpu) {
1845		kdb_printf("go must execute on the entry cpu, "
1846			   "please use \"cpu %d\" and then execute go\n",
1847			   kdb_initial_cpu);
1848		return KDB_BADCPUNUM;
1849	}
1850	if (argc == 1) {
1851		nextarg = 1;
1852		diag = kdbgetaddrarg(argc, argv, &nextarg,
1853				     &addr, &offset, NULL);
1854		if (diag)
1855			return diag;
1856	} else if (argc) {
1857		return KDB_ARGCOUNT;
1858	}
1859
1860	diag = KDB_CMD_GO;
1861	if (KDB_FLAG(CATASTROPHIC)) {
1862		kdb_printf("Catastrophic error detected\n");
1863		kdb_printf("kdb_continue_catastrophic=%d, ",
1864			kdb_continue_catastrophic);
1865		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1866			kdb_printf("type go a second time if you really want "
1867				   "to continue\n");
1868			return 0;
1869		}
1870		if (kdb_continue_catastrophic == 2) {
1871			kdb_printf("forcing reboot\n");
1872			kdb_reboot(0, NULL);
1873		}
1874		kdb_printf("attempting to continue\n");
1875	}
1876	return diag;
1877}
1878
1879/*
1880 * kdb_rd - This function implements the 'rd' command.
1881 */
1882static int kdb_rd(int argc, const char **argv)
1883{
1884	int len = kdb_check_regs();
1885#if DBG_MAX_REG_NUM > 0
1886	int i;
1887	char *rname;
1888	int rsize;
1889	u64 reg64;
1890	u32 reg32;
1891	u16 reg16;
1892	u8 reg8;
1893
1894	if (len)
1895		return len;
1896
1897	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1898		rsize = dbg_reg_def[i].size * 2;
1899		if (rsize > 16)
1900			rsize = 2;
1901		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1902			len = 0;
1903			kdb_printf("\n");
1904		}
1905		if (len)
1906			len += kdb_printf("  ");
1907		switch(dbg_reg_def[i].size * 8) {
1908		case 8:
1909			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1910			if (!rname)
1911				break;
1912			len += kdb_printf("%s: %02x", rname, reg8);
1913			break;
1914		case 16:
1915			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1916			if (!rname)
1917				break;
1918			len += kdb_printf("%s: %04x", rname, reg16);
1919			break;
1920		case 32:
1921			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1922			if (!rname)
1923				break;
1924			len += kdb_printf("%s: %08x", rname, reg32);
1925			break;
1926		case 64:
1927			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1928			if (!rname)
1929				break;
1930			len += kdb_printf("%s: %016llx", rname, reg64);
1931			break;
1932		default:
1933			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1934		}
1935	}
1936	kdb_printf("\n");
1937#else
1938	if (len)
1939		return len;
1940
1941	kdb_dumpregs(kdb_current_regs);
1942#endif
1943	return 0;
1944}
1945
1946/*
1947 * kdb_rm - This function implements the 'rm' (register modify)  command.
1948 *	rm register-name new-contents
1949 * Remarks:
1950 *	Allows register modification with the same restrictions as gdb
1951 */
1952static int kdb_rm(int argc, const char **argv)
1953{
1954#if DBG_MAX_REG_NUM > 0
1955	int diag;
1956	const char *rname;
1957	int i;
1958	u64 reg64;
1959	u32 reg32;
1960	u16 reg16;
1961	u8 reg8;
1962
1963	if (argc != 2)
1964		return KDB_ARGCOUNT;
1965	/*
1966	 * Allow presence or absence of leading '%' symbol.
1967	 */
1968	rname = argv[1];
1969	if (*rname == '%')
1970		rname++;
1971
1972	diag = kdbgetu64arg(argv[2], &reg64);
1973	if (diag)
1974		return diag;
1975
1976	diag = kdb_check_regs();
1977	if (diag)
1978		return diag;
1979
1980	diag = KDB_BADREG;
1981	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1982		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1983			diag = 0;
1984			break;
1985		}
1986	}
1987	if (!diag) {
1988		switch(dbg_reg_def[i].size * 8) {
1989		case 8:
1990			reg8 = reg64;
1991			dbg_set_reg(i, &reg8, kdb_current_regs);
1992			break;
1993		case 16:
1994			reg16 = reg64;
1995			dbg_set_reg(i, &reg16, kdb_current_regs);
1996			break;
1997		case 32:
1998			reg32 = reg64;
1999			dbg_set_reg(i, &reg32, kdb_current_regs);
2000			break;
2001		case 64:
2002			dbg_set_reg(i, &reg64, kdb_current_regs);
2003			break;
2004		}
2005	}
2006	return diag;
2007#else
2008	kdb_printf("ERROR: Register set currently not implemented\n");
2009    return 0;
2010#endif
2011}
2012
2013#if defined(CONFIG_MAGIC_SYSRQ)
2014/*
2015 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
2016 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
2017 *		sr <magic-sysrq-code>
2018 */
2019static int kdb_sr(int argc, const char **argv)
2020{
2021	bool check_mask =
2022	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
2023
2024	if (argc != 1)
2025		return KDB_ARGCOUNT;
2026
2027	kdb_trap_printk++;
2028	__handle_sysrq(*argv[1], check_mask);
2029	kdb_trap_printk--;
2030
2031	return 0;
2032}
2033#endif	/* CONFIG_MAGIC_SYSRQ */
2034
2035/*
2036 * kdb_ef - This function implements the 'regs' (display exception
2037 *	frame) command.  This command takes an address and expects to
2038 *	find an exception frame at that address, formats and prints
2039 *	it.
2040 *		regs address-expression
2041 * Remarks:
2042 *	Not done yet.
2043 */
2044static int kdb_ef(int argc, const char **argv)
2045{
2046	int diag;
2047	unsigned long addr;
2048	long offset;
2049	int nextarg;
2050
2051	if (argc != 1)
2052		return KDB_ARGCOUNT;
2053
2054	nextarg = 1;
2055	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2056	if (diag)
2057		return diag;
2058	show_regs((struct pt_regs *)addr);
2059	return 0;
2060}
2061
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2062/*
2063 * kdb_env - This function implements the 'env' command.  Display the
2064 *	current environment variables.
2065 */
2066
2067static int kdb_env(int argc, const char **argv)
2068{
2069	kdb_printenv();
2070
2071	if (KDB_DEBUG(MASK))
2072		kdb_printf("KDBDEBUG=0x%x\n",
2073			(kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2074
2075	return 0;
2076}
2077
2078#ifdef CONFIG_PRINTK
2079/*
2080 * kdb_dmesg - This function implements the 'dmesg' command to display
2081 *	the contents of the syslog buffer.
2082 *		dmesg [lines] [adjust]
2083 */
2084static int kdb_dmesg(int argc, const char **argv)
2085{
2086	int diag;
2087	int logging;
2088	int lines = 0;
2089	int adjust = 0;
2090	int n = 0;
2091	int skip = 0;
2092	struct kmsg_dump_iter iter;
2093	size_t len;
2094	char buf[201];
2095
2096	if (argc > 2)
2097		return KDB_ARGCOUNT;
2098	if (argc) {
2099		char *cp;
2100		lines = simple_strtol(argv[1], &cp, 0);
2101		if (*cp)
2102			lines = 0;
2103		if (argc > 1) {
2104			adjust = simple_strtoul(argv[2], &cp, 0);
2105			if (*cp || adjust < 0)
2106				adjust = 0;
2107		}
2108	}
2109
2110	/* disable LOGGING if set */
2111	diag = kdbgetintenv("LOGGING", &logging);
2112	if (!diag && logging) {
2113		const char *setargs[] = { "set", "LOGGING", "0" };
2114		kdb_set(2, setargs);
2115	}
2116
2117	kmsg_dump_rewind(&iter);
2118	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2119		n++;
2120
2121	if (lines < 0) {
2122		if (adjust >= n)
2123			kdb_printf("buffer only contains %d lines, nothing "
2124				   "printed\n", n);
2125		else if (adjust - lines >= n)
2126			kdb_printf("buffer only contains %d lines, last %d "
2127				   "lines printed\n", n, n - adjust);
2128		skip = adjust;
2129		lines = abs(lines);
2130	} else if (lines > 0) {
2131		skip = n - lines - adjust;
2132		lines = abs(lines);
2133		if (adjust >= n) {
2134			kdb_printf("buffer only contains %d lines, "
2135				   "nothing printed\n", n);
2136			skip = n;
2137		} else if (skip < 0) {
2138			lines += skip;
2139			skip = 0;
2140			kdb_printf("buffer only contains %d lines, first "
2141				   "%d lines printed\n", n, lines);
2142		}
2143	} else {
2144		lines = n;
2145	}
2146
2147	if (skip >= n || skip < 0)
2148		return 0;
2149
2150	kmsg_dump_rewind(&iter);
2151	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2152		if (skip) {
2153			skip--;
2154			continue;
2155		}
2156		if (!lines--)
2157			break;
2158		if (KDB_FLAG(CMD_INTERRUPT))
2159			return 0;
2160
2161		kdb_printf("%.*s\n", (int)len - 1, buf);
2162	}
2163
2164	return 0;
2165}
2166#endif /* CONFIG_PRINTK */
2167
2168/* Make sure we balance enable/disable calls, must disable first. */
2169static atomic_t kdb_nmi_disabled;
2170
2171static int kdb_disable_nmi(int argc, const char *argv[])
2172{
2173	if (atomic_read(&kdb_nmi_disabled))
2174		return 0;
2175	atomic_set(&kdb_nmi_disabled, 1);
2176	arch_kgdb_ops.enable_nmi(0);
2177	return 0;
2178}
2179
2180static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2181{
2182	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2183		return -EINVAL;
2184	arch_kgdb_ops.enable_nmi(1);
2185	return 0;
2186}
2187
2188static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2189	.set = kdb_param_enable_nmi,
2190};
2191module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2192
2193/*
2194 * kdb_cpu - This function implements the 'cpu' command.
2195 *	cpu	[<cpunum>]
2196 * Returns:
2197 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2198 */
2199static void kdb_cpu_status(void)
2200{
2201	int i, start_cpu, first_print = 1;
2202	char state, prev_state = '?';
2203
2204	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2205	kdb_printf("Available cpus: ");
2206	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2207		if (!cpu_online(i)) {
2208			state = 'F';	/* cpu is offline */
2209		} else if (!kgdb_info[i].enter_kgdb) {
2210			state = 'D';	/* cpu is online but unresponsive */
2211		} else {
2212			state = ' ';	/* cpu is responding to kdb */
2213			if (kdb_task_state_char(KDB_TSK(i)) == '-')
2214				state = '-';	/* idle task */
2215		}
2216		if (state != prev_state) {
2217			if (prev_state != '?') {
2218				if (!first_print)
2219					kdb_printf(", ");
2220				first_print = 0;
2221				kdb_printf("%d", start_cpu);
2222				if (start_cpu < i-1)
2223					kdb_printf("-%d", i-1);
2224				if (prev_state != ' ')
2225					kdb_printf("(%c)", prev_state);
2226			}
2227			prev_state = state;
2228			start_cpu = i;
2229		}
2230	}
2231	/* print the trailing cpus, ignoring them if they are all offline */
2232	if (prev_state != 'F') {
2233		if (!first_print)
2234			kdb_printf(", ");
2235		kdb_printf("%d", start_cpu);
2236		if (start_cpu < i-1)
2237			kdb_printf("-%d", i-1);
2238		if (prev_state != ' ')
2239			kdb_printf("(%c)", prev_state);
2240	}
2241	kdb_printf("\n");
2242}
2243
2244static int kdb_cpu(int argc, const char **argv)
2245{
2246	unsigned long cpunum;
2247	int diag;
2248
2249	if (argc == 0) {
2250		kdb_cpu_status();
2251		return 0;
2252	}
2253
2254	if (argc != 1)
2255		return KDB_ARGCOUNT;
2256
2257	diag = kdbgetularg(argv[1], &cpunum);
2258	if (diag)
2259		return diag;
2260
2261	/*
2262	 * Validate cpunum
2263	 */
2264	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2265		return KDB_BADCPUNUM;
2266
2267	dbg_switch_cpu = cpunum;
2268
2269	/*
2270	 * Switch to other cpu
2271	 */
2272	return KDB_CMD_CPU;
2273}
2274
2275/* The user may not realize that ps/bta with no parameters does not print idle
2276 * or sleeping system daemon processes, so tell them how many were suppressed.
2277 */
2278void kdb_ps_suppressed(void)
2279{
2280	int idle = 0, daemon = 0;
 
 
2281	unsigned long cpu;
2282	const struct task_struct *p, *g;
2283	for_each_online_cpu(cpu) {
2284		p = kdb_curr_task(cpu);
2285		if (kdb_task_state(p, "-"))
2286			++idle;
2287	}
2288	for_each_process_thread(g, p) {
2289		if (kdb_task_state(p, "ims"))
2290			++daemon;
2291	}
2292	if (idle || daemon) {
2293		if (idle)
2294			kdb_printf("%d idle process%s (state -)%s\n",
2295				   idle, idle == 1 ? "" : "es",
2296				   daemon ? " and " : "");
2297		if (daemon)
2298			kdb_printf("%d sleeping system daemon (state [ims]) "
2299				   "process%s", daemon,
2300				   daemon == 1 ? "" : "es");
2301		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2302	}
2303}
2304
 
 
 
 
 
2305void kdb_ps1(const struct task_struct *p)
2306{
2307	int cpu;
2308	unsigned long tmp;
2309
2310	if (!p ||
2311	    copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2312		return;
2313
2314	cpu = kdb_process_cpu(p);
2315	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2316		   (void *)p, p->pid, p->parent->pid,
2317		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2318		   kdb_task_state_char(p),
2319		   (void *)(&p->thread),
2320		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2321		   p->comm);
2322	if (kdb_task_has_cpu(p)) {
2323		if (!KDB_TSK(cpu)) {
2324			kdb_printf("  Error: no saved data for this cpu\n");
2325		} else {
2326			if (KDB_TSK(cpu) != p)
2327				kdb_printf("  Error: does not match running "
2328				   "process table (0x%px)\n", KDB_TSK(cpu));
2329		}
2330	}
2331}
2332
2333/*
2334 * kdb_ps - This function implements the 'ps' command which shows a
2335 *	    list of the active processes.
2336 *
2337 * ps [<state_chars>]   Show processes, optionally selecting only those whose
2338 *                      state character is found in <state_chars>.
2339 */
2340static int kdb_ps(int argc, const char **argv)
2341{
2342	struct task_struct *g, *p;
2343	const char *mask;
2344	unsigned long cpu;
2345
2346	if (argc == 0)
2347		kdb_ps_suppressed();
2348	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2349		(int)(2*sizeof(void *))+2, "Task Addr",
2350		(int)(2*sizeof(void *))+2, "Thread");
2351	mask = argc ? argv[1] : kdbgetenv("PS");
2352	/* Run the active tasks first */
2353	for_each_online_cpu(cpu) {
2354		if (KDB_FLAG(CMD_INTERRUPT))
2355			return 0;
2356		p = kdb_curr_task(cpu);
2357		if (kdb_task_state(p, mask))
2358			kdb_ps1(p);
2359	}
2360	kdb_printf("\n");
2361	/* Now the real tasks */
2362	for_each_process_thread(g, p) {
2363		if (KDB_FLAG(CMD_INTERRUPT))
2364			return 0;
2365		if (kdb_task_state(p, mask))
2366			kdb_ps1(p);
2367	}
2368
2369	return 0;
2370}
2371
2372/*
2373 * kdb_pid - This function implements the 'pid' command which switches
2374 *	the currently active process.
2375 *		pid [<pid> | R]
2376 */
2377static int kdb_pid(int argc, const char **argv)
2378{
2379	struct task_struct *p;
2380	unsigned long val;
2381	int diag;
2382
2383	if (argc > 1)
2384		return KDB_ARGCOUNT;
2385
2386	if (argc) {
2387		if (strcmp(argv[1], "R") == 0) {
2388			p = KDB_TSK(kdb_initial_cpu);
2389		} else {
2390			diag = kdbgetularg(argv[1], &val);
2391			if (diag)
2392				return KDB_BADINT;
2393
2394			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2395			if (!p) {
2396				kdb_printf("No task with pid=%d\n", (pid_t)val);
2397				return 0;
2398			}
2399		}
2400		kdb_set_current_task(p);
2401	}
2402	kdb_printf("KDB current process is %s(pid=%d)\n",
2403		   kdb_current_task->comm,
2404		   kdb_current_task->pid);
2405
2406	return 0;
2407}
2408
2409static int kdb_kgdb(int argc, const char **argv)
2410{
2411	return KDB_CMD_KGDB;
2412}
2413
2414/*
2415 * kdb_help - This function implements the 'help' and '?' commands.
2416 */
2417static int kdb_help(int argc, const char **argv)
2418{
2419	kdbtab_t *kt;
2420
2421	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2422	kdb_printf("-----------------------------"
2423		   "-----------------------------\n");
2424	list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2425		char *space = "";
2426		if (KDB_FLAG(CMD_INTERRUPT))
2427			return 0;
2428		if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true))
2429			continue;
2430		if (strlen(kt->usage) > 20)
2431			space = "\n                                    ";
2432		kdb_printf("%-15.15s %-20s%s%s\n", kt->name,
2433			   kt->usage, space, kt->help);
2434	}
2435	return 0;
2436}
2437
2438/*
2439 * kdb_kill - This function implements the 'kill' commands.
2440 */
2441static int kdb_kill(int argc, const char **argv)
2442{
2443	long sig, pid;
2444	char *endp;
2445	struct task_struct *p;
2446
2447	if (argc != 2)
2448		return KDB_ARGCOUNT;
2449
2450	sig = simple_strtol(argv[1], &endp, 0);
2451	if (*endp)
2452		return KDB_BADINT;
2453	if ((sig >= 0) || !valid_signal(-sig)) {
2454		kdb_printf("Invalid signal parameter.<-signal>\n");
2455		return 0;
2456	}
2457	sig = -sig;
2458
2459	pid = simple_strtol(argv[2], &endp, 0);
2460	if (*endp)
2461		return KDB_BADINT;
2462	if (pid <= 0) {
2463		kdb_printf("Process ID must be large than 0.\n");
2464		return 0;
2465	}
2466
2467	/* Find the process. */
2468	p = find_task_by_pid_ns(pid, &init_pid_ns);
2469	if (!p) {
2470		kdb_printf("The specified process isn't found.\n");
2471		return 0;
2472	}
2473	p = p->group_leader;
2474	kdb_send_sig(p, sig);
2475	return 0;
2476}
2477
2478/*
2479 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2480 * I cannot call that code directly from kdb, it has an unconditional
2481 * cli()/sti() and calls routines that take locks which can stop the debugger.
2482 */
2483static void kdb_sysinfo(struct sysinfo *val)
2484{
2485	u64 uptime = ktime_get_mono_fast_ns();
2486
2487	memset(val, 0, sizeof(*val));
2488	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2489	val->loads[0] = avenrun[0];
2490	val->loads[1] = avenrun[1];
2491	val->loads[2] = avenrun[2];
2492	val->procs = nr_threads-1;
2493	si_meminfo(val);
2494
2495	return;
2496}
2497
2498/*
2499 * kdb_summary - This function implements the 'summary' command.
2500 */
2501static int kdb_summary(int argc, const char **argv)
2502{
2503	time64_t now;
2504	struct sysinfo val;
2505
2506	if (argc)
2507		return KDB_ARGCOUNT;
2508
2509	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2510	kdb_printf("release    %s\n", init_uts_ns.name.release);
2511	kdb_printf("version    %s\n", init_uts_ns.name.version);
2512	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2513	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2514	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2515
2516	now = __ktime_get_real_seconds();
2517	kdb_printf("date       %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
2518	kdb_sysinfo(&val);
2519	kdb_printf("uptime     ");
2520	if (val.uptime > (24*60*60)) {
2521		int days = val.uptime / (24*60*60);
2522		val.uptime %= (24*60*60);
2523		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2524	}
2525	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2526
2527	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2528		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2529		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2530		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2531
2532	/* Display in kilobytes */
2533#define K(x) ((x) << (PAGE_SHIFT - 10))
2534	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2535		   "Buffers:        %8lu kB\n",
2536		   K(val.totalram), K(val.freeram), K(val.bufferram));
2537	return 0;
2538}
2539
2540/*
2541 * kdb_per_cpu - This function implements the 'per_cpu' command.
2542 */
2543static int kdb_per_cpu(int argc, const char **argv)
2544{
2545	char fmtstr[64];
2546	int cpu, diag, nextarg = 1;
2547	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2548
2549	if (argc < 1 || argc > 3)
2550		return KDB_ARGCOUNT;
2551
2552	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2553	if (diag)
2554		return diag;
2555
2556	if (argc >= 2) {
2557		diag = kdbgetularg(argv[2], &bytesperword);
2558		if (diag)
2559			return diag;
2560	}
2561	if (!bytesperword)
2562		bytesperword = KDB_WORD_SIZE;
2563	else if (bytesperword > KDB_WORD_SIZE)
2564		return KDB_BADWIDTH;
2565	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2566	if (argc >= 3) {
2567		diag = kdbgetularg(argv[3], &whichcpu);
2568		if (diag)
2569			return diag;
2570		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2571			kdb_printf("cpu %ld is not online\n", whichcpu);
2572			return KDB_BADCPUNUM;
2573		}
2574	}
2575
2576	/* Most architectures use __per_cpu_offset[cpu], some use
2577	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2578	 */
2579#ifdef	__per_cpu_offset
2580#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2581#else
2582#ifdef	CONFIG_SMP
2583#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2584#else
2585#define KDB_PCU(cpu) 0
2586#endif
2587#endif
2588	for_each_online_cpu(cpu) {
2589		if (KDB_FLAG(CMD_INTERRUPT))
2590			return 0;
2591
2592		if (whichcpu != ~0UL && whichcpu != cpu)
2593			continue;
2594		addr = symaddr + KDB_PCU(cpu);
2595		diag = kdb_getword(&val, addr, bytesperword);
2596		if (diag) {
2597			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2598				   "read, diag=%d\n", cpu, addr, diag);
2599			continue;
2600		}
2601		kdb_printf("%5d ", cpu);
2602		kdb_md_line(fmtstr, addr,
2603			bytesperword == KDB_WORD_SIZE,
2604			1, bytesperword, 1, 1, 0);
2605	}
2606#undef KDB_PCU
2607	return 0;
2608}
2609
2610/*
2611 * display help for the use of cmd | grep pattern
2612 */
2613static int kdb_grep_help(int argc, const char **argv)
2614{
2615	kdb_printf("Usage of  cmd args | grep pattern:\n");
2616	kdb_printf("  Any command's output may be filtered through an ");
2617	kdb_printf("emulated 'pipe'.\n");
2618	kdb_printf("  'grep' is just a key word.\n");
2619	kdb_printf("  The pattern may include a very limited set of "
2620		   "metacharacters:\n");
2621	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2622	kdb_printf("  And if there are spaces in the pattern, you may "
2623		   "quote it:\n");
2624	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2625		   " or \"^pat tern$\"\n");
2626	return 0;
2627}
2628
2629/**
2630 * kdb_register() - This function is used to register a kernel debugger
2631 *                  command.
2632 * @cmd: pointer to kdb command
2633 *
2634 * Note that it's the job of the caller to keep the memory for the cmd
2635 * allocated until unregister is called.
 
 
 
 
2636 */
2637int kdb_register(kdbtab_t *cmd)
 
 
 
 
 
2638{
2639	kdbtab_t *kp;
2640
2641	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2642		if (strcmp(kp->name, cmd->name) == 0) {
2643			kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
2644				   cmd->name, cmd->func, cmd->help);
2645			return 1;
2646		}
2647	}
2648
2649	list_add_tail(&cmd->list_node, &kdb_cmds_head);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2650	return 0;
2651}
2652EXPORT_SYMBOL_GPL(kdb_register);
2653
2654/**
2655 * kdb_register_table() - This function is used to register a kdb command
2656 *                        table.
2657 * @kp: pointer to kdb command table
2658 * @len: length of kdb command table
2659 */
2660void kdb_register_table(kdbtab_t *kp, size_t len)
2661{
2662	while (len--) {
2663		list_add_tail(&kp->list_node, &kdb_cmds_head);
2664		kp++;
2665	}
2666}
2667
2668/**
2669 * kdb_unregister() - This function is used to unregister a kernel debugger
2670 *                    command. It is generally called when a module which
2671 *                    implements kdb command is unloaded.
2672 * @cmd: pointer to kdb command
 
 
 
 
 
 
2673 */
2674void kdb_unregister(kdbtab_t *cmd)
 
 
 
 
2675{
2676	list_del(&cmd->list_node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2677}
2678EXPORT_SYMBOL_GPL(kdb_unregister);
2679
2680static kdbtab_t maintab[] = {
2681	{	.name = "md",
2682		.func = kdb_md,
2683		.usage = "<vaddr>",
2684		.help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2685		.minlen = 1,
2686		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2687	},
2688	{	.name = "mdr",
2689		.func = kdb_md,
2690		.usage = "<vaddr> <bytes>",
2691		.help = "Display Raw Memory",
2692		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2693	},
2694	{	.name = "mdp",
2695		.func = kdb_md,
2696		.usage = "<paddr> <bytes>",
2697		.help = "Display Physical Memory",
2698		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2699	},
2700	{	.name = "mds",
2701		.func = kdb_md,
2702		.usage = "<vaddr>",
2703		.help = "Display Memory Symbolically",
2704		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2705	},
2706	{	.name = "mm",
2707		.func = kdb_mm,
2708		.usage = "<vaddr> <contents>",
2709		.help = "Modify Memory Contents",
2710		.flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2711	},
2712	{	.name = "go",
2713		.func = kdb_go,
2714		.usage = "[<vaddr>]",
2715		.help = "Continue Execution",
2716		.minlen = 1,
2717		.flags = KDB_ENABLE_REG_WRITE |
2718			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2719	},
2720	{	.name = "rd",
2721		.func = kdb_rd,
2722		.usage = "",
2723		.help = "Display Registers",
2724		.flags = KDB_ENABLE_REG_READ,
2725	},
2726	{	.name = "rm",
2727		.func = kdb_rm,
2728		.usage = "<reg> <contents>",
2729		.help = "Modify Registers",
2730		.flags = KDB_ENABLE_REG_WRITE,
2731	},
2732	{	.name = "ef",
2733		.func = kdb_ef,
2734		.usage = "<vaddr>",
2735		.help = "Display exception frame",
2736		.flags = KDB_ENABLE_MEM_READ,
2737	},
2738	{	.name = "bt",
2739		.func = kdb_bt,
2740		.usage = "[<vaddr>]",
2741		.help = "Stack traceback",
2742		.minlen = 1,
2743		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2744	},
2745	{	.name = "btp",
2746		.func = kdb_bt,
2747		.usage = "<pid>",
2748		.help = "Display stack for process <pid>",
2749		.flags = KDB_ENABLE_INSPECT,
2750	},
2751	{	.name = "bta",
2752		.func = kdb_bt,
2753		.usage = "[<state_chars>|A]",
2754		.help = "Backtrace all processes whose state matches",
2755		.flags = KDB_ENABLE_INSPECT,
2756	},
2757	{	.name = "btc",
2758		.func = kdb_bt,
2759		.usage = "",
2760		.help = "Backtrace current process on each cpu",
2761		.flags = KDB_ENABLE_INSPECT,
2762	},
2763	{	.name = "btt",
2764		.func = kdb_bt,
2765		.usage = "<vaddr>",
2766		.help = "Backtrace process given its struct task address",
2767		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2768	},
2769	{	.name = "env",
2770		.func = kdb_env,
2771		.usage = "",
2772		.help = "Show environment variables",
2773		.flags = KDB_ENABLE_ALWAYS_SAFE,
2774	},
2775	{	.name = "set",
2776		.func = kdb_set,
2777		.usage = "",
2778		.help = "Set environment variables",
2779		.flags = KDB_ENABLE_ALWAYS_SAFE,
2780	},
2781	{	.name = "help",
2782		.func = kdb_help,
2783		.usage = "",
2784		.help = "Display Help Message",
2785		.minlen = 1,
2786		.flags = KDB_ENABLE_ALWAYS_SAFE,
2787	},
2788	{	.name = "?",
2789		.func = kdb_help,
2790		.usage = "",
2791		.help = "Display Help Message",
2792		.flags = KDB_ENABLE_ALWAYS_SAFE,
2793	},
2794	{	.name = "cpu",
2795		.func = kdb_cpu,
2796		.usage = "<cpunum>",
2797		.help = "Switch to new cpu",
2798		.flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2799	},
2800	{	.name = "kgdb",
2801		.func = kdb_kgdb,
2802		.usage = "",
2803		.help = "Enter kgdb mode",
2804		.flags = 0,
2805	},
2806	{	.name = "ps",
2807		.func = kdb_ps,
2808		.usage = "[<state_chars>|A]",
2809		.help = "Display active task list",
2810		.flags = KDB_ENABLE_INSPECT,
2811	},
2812	{	.name = "pid",
2813		.func = kdb_pid,
2814		.usage = "<pidnum>",
2815		.help = "Switch to another task",
2816		.flags = KDB_ENABLE_INSPECT,
2817	},
2818	{	.name = "reboot",
2819		.func = kdb_reboot,
2820		.usage = "",
2821		.help = "Reboot the machine immediately",
2822		.flags = KDB_ENABLE_REBOOT,
2823	},
2824#if defined(CONFIG_MODULES)
2825	{	.name = "lsmod",
2826		.func = kdb_lsmod,
2827		.usage = "",
2828		.help = "List loaded kernel modules",
2829		.flags = KDB_ENABLE_INSPECT,
2830	},
2831#endif
2832#if defined(CONFIG_MAGIC_SYSRQ)
2833	{	.name = "sr",
2834		.func = kdb_sr,
2835		.usage = "<key>",
2836		.help = "Magic SysRq key",
2837		.flags = KDB_ENABLE_ALWAYS_SAFE,
2838	},
2839#endif
2840#if defined(CONFIG_PRINTK)
2841	{	.name = "dmesg",
2842		.func = kdb_dmesg,
2843		.usage = "[lines]",
2844		.help = "Display syslog buffer",
2845		.flags = KDB_ENABLE_ALWAYS_SAFE,
2846	},
2847#endif
2848	{	.name = "defcmd",
2849		.func = kdb_defcmd,
2850		.usage = "name \"usage\" \"help\"",
2851		.help = "Define a set of commands, down to endefcmd",
2852		/*
2853		 * Macros are always safe because when executed each
2854		 * internal command re-enters kdb_parse() and is safety
2855		 * checked individually.
2856		 */
2857		.flags = KDB_ENABLE_ALWAYS_SAFE,
2858	},
2859	{	.name = "kill",
2860		.func = kdb_kill,
2861		.usage = "<-signal> <pid>",
2862		.help = "Send a signal to a process",
2863		.flags = KDB_ENABLE_SIGNAL,
2864	},
2865	{	.name = "summary",
2866		.func = kdb_summary,
2867		.usage = "",
2868		.help = "Summarize the system",
2869		.minlen = 4,
2870		.flags = KDB_ENABLE_ALWAYS_SAFE,
2871	},
2872	{	.name = "per_cpu",
2873		.func = kdb_per_cpu,
2874		.usage = "<sym> [<bytes>] [<cpu>]",
2875		.help = "Display per_cpu variables",
2876		.minlen = 3,
2877		.flags = KDB_ENABLE_MEM_READ,
2878	},
2879	{	.name = "grephelp",
2880		.func = kdb_grep_help,
2881		.usage = "",
2882		.help = "Display help on | grep",
2883		.flags = KDB_ENABLE_ALWAYS_SAFE,
2884	},
2885};
2886
2887static kdbtab_t nmicmd = {
2888	.name = "disable_nmi",
2889	.func = kdb_disable_nmi,
2890	.usage = "",
2891	.help = "Disable NMI entry to KDB",
2892	.flags = KDB_ENABLE_ALWAYS_SAFE,
2893};
2894
2895/* Initialize the kdb command table. */
2896static void __init kdb_inittab(void)
2897{
2898	kdb_register_table(maintab, ARRAY_SIZE(maintab));
2899	if (arch_kgdb_ops.enable_nmi)
2900		kdb_register_table(&nmicmd, 1);
2901}
2902
2903/* Execute any commands defined in kdb_cmds.  */
2904static void __init kdb_cmd_init(void)
2905{
2906	int i, diag;
2907	for (i = 0; kdb_cmds[i]; ++i) {
2908		diag = kdb_parse(kdb_cmds[i]);
2909		if (diag)
2910			kdb_printf("kdb command %s failed, kdb diag %d\n",
2911				kdb_cmds[i], diag);
2912	}
2913	if (defcmd_in_progress) {
2914		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2915		kdb_parse("endefcmd");
2916	}
2917}
2918
2919/* Initialize kdb_printf, breakpoint tables and kdb state */
2920void __init kdb_init(int lvl)
2921{
2922	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2923	int i;
2924
2925	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2926		return;
2927	for (i = kdb_init_lvl; i < lvl; i++) {
2928		switch (i) {
2929		case KDB_NOT_INITIALIZED:
2930			kdb_inittab();		/* Initialize Command Table */
2931			kdb_initbptab();	/* Initialize Breakpoints */
2932			break;
2933		case KDB_INIT_EARLY:
2934			kdb_cmd_init();		/* Build kdb_cmds tables */
2935			break;
2936		}
2937	}
2938	kdb_init_lvl = lvl;
2939}
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}