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