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v6.8
   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 *	bytes	The number of bytes to allocate in the static buffer.
 
 
 276 * Returns:
 277 *	A pointer to the allocated space in the buffer on success.
 278 *	NULL if bytes > size available in the envbuffer.
 279 * Remarks:
 280 *	We use a static environment buffer (envbuffer) to hold the values
 281 *	of dynamically generated environment variables (see kdb_set).  Buffer
 282 *	space once allocated is never free'd, so over time, the amount of space
 283 *	(currently 512 bytes) will be exhausted if env variables are changed
 284 *	frequently.
 285 */
 286static char *kdballocenv(size_t bytes)
 287{
 288#define	KDB_ENVBUFSIZE	512
 289	static char envbuffer[KDB_ENVBUFSIZE];
 290	static int envbufsize;
 291	char *ep = NULL;
 292
 293	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 294		ep = &envbuffer[envbufsize];
 295		envbufsize += bytes;
 296	}
 297	return ep;
 298}
 299
 300/*
 301 * kdbgetulenv - This function will return the value of an unsigned
 302 *	long-valued environment variable.
 303 * Parameters:
 304 *	match	A character string representing a numeric value
 305 * Outputs:
 306 *	*value  the unsigned long representation of the env variable 'match'
 307 * Returns:
 308 *	Zero on success, a kdb diagnostic on failure.
 309 */
 310static int kdbgetulenv(const char *match, unsigned long *value)
 311{
 312	char *ep;
 313
 314	ep = kdbgetenv(match);
 315	if (!ep)
 316		return KDB_NOTENV;
 317	if (strlen(ep) == 0)
 318		return KDB_NOENVVALUE;
 319
 320	*value = simple_strtoul(ep, NULL, 0);
 321
 322	return 0;
 323}
 324
 325/*
 326 * kdbgetintenv - This function will return the value of an
 327 *	integer-valued environment variable.
 328 * Parameters:
 329 *	match	A character string representing an integer-valued env variable
 330 * Outputs:
 331 *	*value  the integer representation of the environment variable 'match'
 332 * Returns:
 333 *	Zero on success, a kdb diagnostic on failure.
 334 */
 335int kdbgetintenv(const char *match, int *value)
 336{
 337	unsigned long val;
 338	int diag;
 339
 340	diag = kdbgetulenv(match, &val);
 341	if (!diag)
 342		*value = (int) val;
 343	return diag;
 344}
 345
 346/*
 347 * kdb_setenv() - Alter an existing environment variable or create a new one.
 348 * @var: Name of the variable
 349 * @val: Value of the variable
 350 *
 351 * Return: Zero on success, a kdb diagnostic on failure.
 352 */
 353static int kdb_setenv(const char *var, const char *val)
 354{
 355	int i;
 356	char *ep;
 357	size_t varlen, vallen;
 358
 359	varlen = strlen(var);
 360	vallen = strlen(val);
 361	ep = kdballocenv(varlen + vallen + 2);
 362	if (ep == (char *)0)
 363		return KDB_ENVBUFFULL;
 364
 365	sprintf(ep, "%s=%s", var, val);
 366
 367	for (i = 0; i < __nenv; i++) {
 368		if (__env[i]
 369		 && ((strncmp(__env[i], var, varlen) == 0)
 370		   && ((__env[i][varlen] == '\0')
 371		    || (__env[i][varlen] == '=')))) {
 372			__env[i] = ep;
 373			return 0;
 374		}
 375	}
 376
 377	/*
 378	 * Wasn't existing variable.  Fit into slot.
 379	 */
 380	for (i = 0; i < __nenv-1; i++) {
 381		if (__env[i] == (char *)0) {
 382			__env[i] = ep;
 383			return 0;
 384		}
 385	}
 386
 387	return KDB_ENVFULL;
 388}
 389
 390/*
 391 * kdb_printenv() - Display the current environment variables.
 392 */
 393static void kdb_printenv(void)
 394{
 395	int i;
 396
 397	for (i = 0; i < __nenv; i++) {
 398		if (__env[i])
 399			kdb_printf("%s\n", __env[i]);
 400	}
 401}
 402
 403/*
 404 * kdbgetularg - This function will convert a numeric string into an
 405 *	unsigned long value.
 406 * Parameters:
 407 *	arg	A character string representing a numeric value
 408 * Outputs:
 409 *	*value  the unsigned long representation of arg.
 410 * Returns:
 411 *	Zero on success, a kdb diagnostic on failure.
 412 */
 413int kdbgetularg(const char *arg, unsigned long *value)
 414{
 415	char *endp;
 416	unsigned long val;
 417
 418	val = simple_strtoul(arg, &endp, 0);
 419
 420	if (endp == arg) {
 421		/*
 422		 * Also try base 16, for us folks too lazy to type the
 423		 * leading 0x...
 424		 */
 425		val = simple_strtoul(arg, &endp, 16);
 426		if (endp == arg)
 427			return KDB_BADINT;
 428	}
 429
 430	*value = val;
 431
 432	return 0;
 433}
 434
 435int kdbgetu64arg(const char *arg, u64 *value)
 436{
 437	char *endp;
 438	u64 val;
 439
 440	val = simple_strtoull(arg, &endp, 0);
 441
 442	if (endp == arg) {
 443
 444		val = simple_strtoull(arg, &endp, 16);
 445		if (endp == arg)
 446			return KDB_BADINT;
 447	}
 448
 449	*value = val;
 450
 451	return 0;
 452}
 453
 454/*
 455 * kdb_set - This function implements the 'set' command.  Alter an
 456 *	existing environment variable or create a new one.
 457 */
 458int kdb_set(int argc, const char **argv)
 459{
 
 
 
 
 460	/*
 461	 * we can be invoked two ways:
 462	 *   set var=value    argv[1]="var", argv[2]="value"
 463	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 464	 * - if the latter, shift 'em down.
 465	 */
 466	if (argc == 3) {
 467		argv[2] = argv[3];
 468		argc--;
 469	}
 470
 471	if (argc != 2)
 472		return KDB_ARGCOUNT;
 473
 474	/*
 475	 * Censor sensitive variables
 476	 */
 477	if (strcmp(argv[1], "PROMPT") == 0 &&
 478	    !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
 479		return KDB_NOPERM;
 480
 481	/*
 482	 * Check for internal variables
 483	 */
 484	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 485		unsigned int debugflags;
 486		char *cp;
 487
 488		debugflags = simple_strtoul(argv[2], &cp, 0);
 489		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 490			kdb_printf("kdb: illegal debug flags '%s'\n",
 491				    argv[2]);
 492			return 0;
 493		}
 494		kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
 
 495			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 496
 497		return 0;
 498	}
 499
 500	/*
 501	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 502	 * name, argv[2] = value.
 503	 */
 504	return kdb_setenv(argv[1], argv[2]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 505}
 506
 507static int kdb_check_regs(void)
 508{
 509	if (!kdb_current_regs) {
 510		kdb_printf("No current kdb registers."
 511			   "  You may need to select another task\n");
 512		return KDB_BADREG;
 513	}
 514	return 0;
 515}
 516
 517/*
 518 * kdbgetaddrarg - This function is responsible for parsing an
 519 *	address-expression and returning the value of the expression,
 520 *	symbol name, and offset to the caller.
 521 *
 522 *	The argument may consist of a numeric value (decimal or
 523 *	hexadecimal), a symbol name, a register name (preceded by the
 524 *	percent sign), an environment variable with a numeric value
 525 *	(preceded by a dollar sign) or a simple arithmetic expression
 526 *	consisting of a symbol name, +/-, and a numeric constant value
 527 *	(offset).
 528 * Parameters:
 529 *	argc	- count of arguments in argv
 530 *	argv	- argument vector
 531 *	*nextarg - index to next unparsed argument in argv[]
 532 *	regs	- Register state at time of KDB entry
 533 * Outputs:
 534 *	*value	- receives the value of the address-expression
 535 *	*offset - receives the offset specified, if any
 536 *	*name   - receives the symbol name, if any
 537 *	*nextarg - index to next unparsed argument in argv[]
 538 * Returns:
 539 *	zero is returned on success, a kdb diagnostic code is
 540 *      returned on error.
 541 */
 542int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 543		  unsigned long *value,  long *offset,
 544		  char **name)
 545{
 546	unsigned long addr;
 547	unsigned long off = 0;
 548	int positive;
 549	int diag;
 550	int found = 0;
 551	char *symname;
 552	char symbol = '\0';
 553	char *cp;
 554	kdb_symtab_t symtab;
 555
 556	/*
 557	 * If the enable flags prohibit both arbitrary memory access
 558	 * and flow control then there are no reasonable grounds to
 559	 * provide symbol lookup.
 560	 */
 561	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 562			     kdb_cmd_enabled, false))
 563		return KDB_NOPERM;
 564
 565	/*
 566	 * Process arguments which follow the following syntax:
 567	 *
 568	 *  symbol | numeric-address [+/- numeric-offset]
 569	 *  %register
 570	 *  $environment-variable
 571	 */
 572
 573	if (*nextarg > argc)
 574		return KDB_ARGCOUNT;
 575
 576	symname = (char *)argv[*nextarg];
 577
 578	/*
 579	 * If there is no whitespace between the symbol
 580	 * or address and the '+' or '-' symbols, we
 581	 * remember the character and replace it with a
 582	 * null so the symbol/value can be properly parsed
 583	 */
 584	cp = strpbrk(symname, "+-");
 585	if (cp != NULL) {
 586		symbol = *cp;
 587		*cp++ = '\0';
 588	}
 589
 590	if (symname[0] == '$') {
 591		diag = kdbgetulenv(&symname[1], &addr);
 592		if (diag)
 593			return diag;
 594	} else if (symname[0] == '%') {
 595		diag = kdb_check_regs();
 596		if (diag)
 597			return diag;
 598		/* Implement register values with % at a later time as it is
 599		 * arch optional.
 600		 */
 601		return KDB_NOTIMP;
 602	} else {
 603		found = kdbgetsymval(symname, &symtab);
 604		if (found) {
 605			addr = symtab.sym_start;
 606		} else {
 607			diag = kdbgetularg(argv[*nextarg], &addr);
 608			if (diag)
 609				return diag;
 610		}
 611	}
 612
 613	if (!found)
 614		found = kdbnearsym(addr, &symtab);
 615
 616	(*nextarg)++;
 617
 618	if (name)
 619		*name = symname;
 620	if (value)
 621		*value = addr;
 622	if (offset && name && *name)
 623		*offset = addr - symtab.sym_start;
 624
 625	if ((*nextarg > argc)
 626	 && (symbol == '\0'))
 627		return 0;
 628
 629	/*
 630	 * check for +/- and offset
 631	 */
 632
 633	if (symbol == '\0') {
 634		if ((argv[*nextarg][0] != '+')
 635		 && (argv[*nextarg][0] != '-')) {
 636			/*
 637			 * Not our argument.  Return.
 638			 */
 639			return 0;
 640		} else {
 641			positive = (argv[*nextarg][0] == '+');
 642			(*nextarg)++;
 643		}
 644	} else
 645		positive = (symbol == '+');
 646
 647	/*
 648	 * Now there must be an offset!
 649	 */
 650	if ((*nextarg > argc)
 651	 && (symbol == '\0')) {
 652		return KDB_INVADDRFMT;
 653	}
 654
 655	if (!symbol) {
 656		cp = (char *)argv[*nextarg];
 657		(*nextarg)++;
 658	}
 659
 660	diag = kdbgetularg(cp, &off);
 661	if (diag)
 662		return diag;
 663
 664	if (!positive)
 665		off = -off;
 666
 667	if (offset)
 668		*offset += off;
 669
 670	if (value)
 671		*value += off;
 672
 673	return 0;
 674}
 675
 676static void kdb_cmderror(int diag)
 677{
 678	int i;
 679
 680	if (diag >= 0) {
 681		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 682		return;
 683	}
 684
 685	for (i = 0; i < __nkdb_err; i++) {
 686		if (kdbmsgs[i].km_diag == diag) {
 687			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 688			return;
 689		}
 690	}
 691
 692	kdb_printf("Unknown diag %d\n", -diag);
 693}
 694
 695/*
 696 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 697 *	command which defines one command as a set of other commands,
 698 *	terminated by endefcmd.  kdb_defcmd processes the initial
 699 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 700 *	the following commands until 'endefcmd'.
 701 * Inputs:
 702 *	argc	argument count
 703 *	argv	argument vector
 704 * Returns:
 705 *	zero for success, a kdb diagnostic if error
 706 */
 707struct kdb_macro {
 708	kdbtab_t cmd;			/* Macro command */
 709	struct list_head statements;	/* Associated statement list */
 
 
 
 
 710};
 711
 712struct kdb_macro_statement {
 713	char *statement;		/* Statement text */
 714	struct list_head list_node;	/* Statement list node */
 715};
 716
 717static struct kdb_macro *kdb_macro;
 718static bool defcmd_in_progress;
 719
 720/* Forward references */
 721static int kdb_exec_defcmd(int argc, const char **argv);
 722
 723static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 724{
 725	struct kdb_macro_statement *kms;
 726
 727	if (!kdb_macro)
 728		return KDB_NOTIMP;
 729
 730	if (strcmp(argv0, "endefcmd") == 0) {
 731		defcmd_in_progress = false;
 732		if (!list_empty(&kdb_macro->statements))
 733			kdb_register(&kdb_macro->cmd);
 
 
 
 
 
 
 
 
 734		return 0;
 735	}
 736
 737	kms = kmalloc(sizeof(*kms), GFP_KDB);
 738	if (!kms) {
 739		kdb_printf("Could not allocate new kdb macro command: %s\n",
 
 740			   cmdstr);
 
 741		return KDB_NOTIMP;
 742	}
 743
 744	kms->statement = kdb_strdup(cmdstr, GFP_KDB);
 745	list_add_tail(&kms->list_node, &kdb_macro->statements);
 746
 747	return 0;
 748}
 749
 750static int kdb_defcmd(int argc, const char **argv)
 751{
 752	kdbtab_t *mp;
 753
 754	if (defcmd_in_progress) {
 755		kdb_printf("kdb: nested defcmd detected, assuming missing "
 756			   "endefcmd\n");
 757		kdb_defcmd2("endefcmd", "endefcmd");
 758	}
 759	if (argc == 0) {
 760		kdbtab_t *kp;
 761		struct kdb_macro *kmp;
 762		struct kdb_macro_statement *kms;
 763
 764		list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 765			if (kp->func == kdb_exec_defcmd) {
 766				kdb_printf("defcmd %s \"%s\" \"%s\"\n",
 767					   kp->name, kp->usage, kp->help);
 768				kmp = container_of(kp, struct kdb_macro, cmd);
 769				list_for_each_entry(kms, &kmp->statements,
 770						    list_node)
 771					kdb_printf("%s", kms->statement);
 772				kdb_printf("endefcmd\n");
 773			}
 774		}
 775		return 0;
 776	}
 777	if (argc != 3)
 778		return KDB_ARGCOUNT;
 779	if (in_dbg_master()) {
 780		kdb_printf("Command only available during kdb_init()\n");
 781		return KDB_NOTIMP;
 782	}
 783	kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);
 784	if (!kdb_macro)
 
 785		goto fail_defcmd;
 786
 787	mp = &kdb_macro->cmd;
 788	mp->func = kdb_exec_defcmd;
 789	mp->minlen = 0;
 790	mp->flags = KDB_ENABLE_ALWAYS_SAFE;
 791	mp->name = kdb_strdup(argv[1], GFP_KDB);
 792	if (!mp->name)
 793		goto fail_name;
 794	mp->usage = kdb_strdup(argv[2], GFP_KDB);
 795	if (!mp->usage)
 796		goto fail_usage;
 797	mp->help = kdb_strdup(argv[3], GFP_KDB);
 798	if (!mp->help)
 799		goto fail_help;
 800	if (mp->usage[0] == '"') {
 801		strcpy(mp->usage, argv[2]+1);
 802		mp->usage[strlen(mp->usage)-1] = '\0';
 803	}
 804	if (mp->help[0] == '"') {
 805		strcpy(mp->help, argv[3]+1);
 806		mp->help[strlen(mp->help)-1] = '\0';
 807	}
 808
 809	INIT_LIST_HEAD(&kdb_macro->statements);
 810	defcmd_in_progress = true;
 
 811	return 0;
 812fail_help:
 813	kfree(mp->usage);
 814fail_usage:
 815	kfree(mp->name);
 816fail_name:
 817	kfree(kdb_macro);
 818fail_defcmd:
 819	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
 
 820	return KDB_NOTIMP;
 821}
 822
 823/*
 824 * kdb_exec_defcmd - Execute the set of commands associated with this
 825 *	defcmd name.
 826 * Inputs:
 827 *	argc	argument count
 828 *	argv	argument vector
 829 * Returns:
 830 *	zero for success, a kdb diagnostic if error
 831 */
 832static int kdb_exec_defcmd(int argc, const char **argv)
 833{
 834	int ret;
 835	kdbtab_t *kp;
 836	struct kdb_macro *kmp;
 837	struct kdb_macro_statement *kms;
 838
 839	if (argc != 0)
 840		return KDB_ARGCOUNT;
 841
 842	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 843		if (strcmp(kp->name, argv[0]) == 0)
 844			break;
 845	}
 846	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
 847		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 848			   argv[0]);
 849		return KDB_NOTIMP;
 850	}
 851	kmp = container_of(kp, struct kdb_macro, cmd);
 852	list_for_each_entry(kms, &kmp->statements, list_node) {
 853		/*
 854		 * Recursive use of kdb_parse, do not use argv after this point.
 855		 */
 856		argv = NULL;
 857		kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement);
 858		ret = kdb_parse(kms->statement);
 859		if (ret)
 860			return ret;
 861	}
 862	return 0;
 863}
 864
 865/* Command history */
 866#define KDB_CMD_HISTORY_COUNT	32
 867#define CMD_BUFLEN		200	/* kdb_printf: max printline
 868					 * size == 256 */
 869static unsigned int cmd_head, cmd_tail;
 870static unsigned int cmdptr;
 871static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 872static char cmd_cur[CMD_BUFLEN];
 873
 874/*
 875 * The "str" argument may point to something like  | grep xyz
 876 */
 877static void parse_grep(const char *str)
 878{
 879	int	len;
 880	char	*cp = (char *)str, *cp2;
 881
 882	/* sanity check: we should have been called with the \ first */
 883	if (*cp != '|')
 884		return;
 885	cp++;
 886	while (isspace(*cp))
 887		cp++;
 888	if (!str_has_prefix(cp, "grep ")) {
 889		kdb_printf("invalid 'pipe', see grephelp\n");
 890		return;
 891	}
 892	cp += 5;
 893	while (isspace(*cp))
 894		cp++;
 895	cp2 = strchr(cp, '\n');
 896	if (cp2)
 897		*cp2 = '\0'; /* remove the trailing newline */
 898	len = strlen(cp);
 899	if (len == 0) {
 900		kdb_printf("invalid 'pipe', see grephelp\n");
 901		return;
 902	}
 903	/* now cp points to a nonzero length search string */
 904	if (*cp == '"') {
 905		/* allow it be "x y z" by removing the "'s - there must
 906		   be two of them */
 907		cp++;
 908		cp2 = strchr(cp, '"');
 909		if (!cp2) {
 910			kdb_printf("invalid quoted string, see grephelp\n");
 911			return;
 912		}
 913		*cp2 = '\0'; /* end the string where the 2nd " was */
 914	}
 915	kdb_grep_leading = 0;
 916	if (*cp == '^') {
 917		kdb_grep_leading = 1;
 918		cp++;
 919	}
 920	len = strlen(cp);
 921	kdb_grep_trailing = 0;
 922	if (*(cp+len-1) == '$') {
 923		kdb_grep_trailing = 1;
 924		*(cp+len-1) = '\0';
 925	}
 926	len = strlen(cp);
 927	if (!len)
 928		return;
 929	if (len >= KDB_GREP_STRLEN) {
 930		kdb_printf("search string too long\n");
 931		return;
 932	}
 933	strcpy(kdb_grep_string, cp);
 934	kdb_grepping_flag++;
 935	return;
 936}
 937
 938/*
 939 * kdb_parse - Parse the command line, search the command table for a
 940 *	matching command and invoke the command function.  This
 941 *	function may be called recursively, if it is, the second call
 942 *	will overwrite argv and cbuf.  It is the caller's
 943 *	responsibility to save their argv if they recursively call
 944 *	kdb_parse().
 945 * Parameters:
 946 *      cmdstr	The input command line to be parsed.
 947 *	regs	The registers at the time kdb was entered.
 948 * Returns:
 949 *	Zero for success, a kdb diagnostic if failure.
 950 * Remarks:
 951 *	Limited to 20 tokens.
 952 *
 953 *	Real rudimentary tokenization. Basically only whitespace
 954 *	is considered a token delimiter (but special consideration
 955 *	is taken of the '=' sign as used by the 'set' command).
 956 *
 957 *	The algorithm used to tokenize the input string relies on
 958 *	there being at least one whitespace (or otherwise useless)
 959 *	character between tokens as the character immediately following
 960 *	the token is altered in-place to a null-byte to terminate the
 961 *	token string.
 962 */
 963
 964#define MAXARGC	20
 965
 966int kdb_parse(const char *cmdstr)
 967{
 968	static char *argv[MAXARGC];
 969	static int argc;
 970	static char cbuf[CMD_BUFLEN+2];
 971	char *cp;
 972	char *cpp, quoted;
 973	kdbtab_t *tp;
 974	int escaped, ignore_errors = 0, check_grep = 0;
 975
 976	/*
 977	 * First tokenize the command string.
 978	 */
 979	cp = (char *)cmdstr;
 980
 981	if (KDB_FLAG(CMD_INTERRUPT)) {
 982		/* Previous command was interrupted, newline must not
 983		 * repeat the command */
 984		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 985		KDB_STATE_SET(PAGER);
 986		argc = 0;	/* no repeat */
 987	}
 988
 989	if (*cp != '\n' && *cp != '\0') {
 990		argc = 0;
 991		cpp = cbuf;
 992		while (*cp) {
 993			/* skip whitespace */
 994			while (isspace(*cp))
 995				cp++;
 996			if ((*cp == '\0') || (*cp == '\n') ||
 997			    (*cp == '#' && !defcmd_in_progress))
 998				break;
 999			/* special case: check for | grep pattern */
1000			if (*cp == '|') {
1001				check_grep++;
1002				break;
1003			}
1004			if (cpp >= cbuf + CMD_BUFLEN) {
1005				kdb_printf("kdb_parse: command buffer "
1006					   "overflow, command ignored\n%s\n",
1007					   cmdstr);
1008				return KDB_NOTFOUND;
1009			}
1010			if (argc >= MAXARGC - 1) {
1011				kdb_printf("kdb_parse: too many arguments, "
1012					   "command ignored\n%s\n", cmdstr);
1013				return KDB_NOTFOUND;
1014			}
1015			argv[argc++] = cpp;
1016			escaped = 0;
1017			quoted = '\0';
1018			/* Copy to next unquoted and unescaped
1019			 * whitespace or '=' */
1020			while (*cp && *cp != '\n' &&
1021			       (escaped || quoted || !isspace(*cp))) {
1022				if (cpp >= cbuf + CMD_BUFLEN)
1023					break;
1024				if (escaped) {
1025					escaped = 0;
1026					*cpp++ = *cp++;
1027					continue;
1028				}
1029				if (*cp == '\\') {
1030					escaped = 1;
1031					++cp;
1032					continue;
1033				}
1034				if (*cp == quoted)
1035					quoted = '\0';
1036				else if (*cp == '\'' || *cp == '"')
1037					quoted = *cp;
1038				*cpp = *cp++;
1039				if (*cpp == '=' && !quoted)
1040					break;
1041				++cpp;
1042			}
1043			*cpp++ = '\0';	/* Squash a ws or '=' character */
1044		}
1045	}
1046	if (!argc)
1047		return 0;
1048	if (check_grep)
1049		parse_grep(cp);
1050	if (defcmd_in_progress) {
1051		int result = kdb_defcmd2(cmdstr, argv[0]);
1052		if (!defcmd_in_progress) {
1053			argc = 0;	/* avoid repeat on endefcmd */
1054			*(argv[0]) = '\0';
1055		}
1056		return result;
1057	}
1058	if (argv[0][0] == '-' && argv[0][1] &&
1059	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1060		ignore_errors = 1;
1061		++argv[0];
1062	}
1063
1064	list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1065		/*
1066		 * If this command is allowed to be abbreviated,
1067		 * check to see if this is it.
1068		 */
1069		if (tp->minlen && (strlen(argv[0]) <= tp->minlen) &&
1070		    (strncmp(argv[0], tp->name, tp->minlen) == 0))
1071			break;
1072
1073		if (strcmp(argv[0], tp->name) == 0)
1074			break;
 
 
 
 
 
 
 
 
 
 
1075	}
1076
1077	/*
1078	 * If we don't find a command by this name, see if the first
1079	 * few characters of this match any of the known commands.
1080	 * e.g., md1c20 should match md.
1081	 */
1082	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1083		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1084			if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0)
1085				break;
 
 
 
 
 
1086		}
1087	}
1088
1089	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1090		int result;
1091
1092		if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1))
1093			return KDB_NOPERM;
1094
1095		KDB_STATE_SET(CMD);
1096		result = (*tp->func)(argc-1, (const char **)argv);
1097		if (result && ignore_errors && result > KDB_CMD_GO)
1098			result = 0;
1099		KDB_STATE_CLEAR(CMD);
1100
1101		if (tp->flags & KDB_REPEAT_WITH_ARGS)
1102			return result;
1103
1104		argc = tp->flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1105		if (argv[argc])
1106			*(argv[argc]) = '\0';
1107		return result;
1108	}
1109
1110	/*
1111	 * If the input with which we were presented does not
1112	 * map to an existing command, attempt to parse it as an
1113	 * address argument and display the result.   Useful for
1114	 * obtaining the address of a variable, or the nearest symbol
1115	 * to an address contained in a register.
1116	 */
1117	{
1118		unsigned long value;
1119		char *name = NULL;
1120		long offset;
1121		int nextarg = 0;
1122
1123		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1124				  &value, &offset, &name)) {
1125			return KDB_NOTFOUND;
1126		}
1127
1128		kdb_printf("%s = ", argv[0]);
1129		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1130		kdb_printf("\n");
1131		return 0;
1132	}
1133}
1134
1135
1136static int handle_ctrl_cmd(char *cmd)
1137{
1138#define CTRL_P	16
1139#define CTRL_N	14
1140
1141	/* initial situation */
1142	if (cmd_head == cmd_tail)
1143		return 0;
1144	switch (*cmd) {
1145	case CTRL_P:
1146		if (cmdptr != cmd_tail)
1147			cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) %
1148				 KDB_CMD_HISTORY_COUNT;
1149		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1150		return 1;
1151	case CTRL_N:
1152		if (cmdptr != cmd_head)
1153			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1154		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1155		return 1;
1156	}
1157	return 0;
1158}
1159
1160/*
1161 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1162 *	the system immediately, or loop for ever on failure.
1163 */
1164static int kdb_reboot(int argc, const char **argv)
1165{
1166	emergency_restart();
1167	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1168	while (1)
1169		cpu_relax();
1170	/* NOTREACHED */
1171	return 0;
1172}
1173
1174static void kdb_dumpregs(struct pt_regs *regs)
1175{
1176	int old_lvl = console_loglevel;
1177	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1178	kdb_trap_printk++;
1179	show_regs(regs);
1180	kdb_trap_printk--;
1181	kdb_printf("\n");
1182	console_loglevel = old_lvl;
1183}
1184
1185static void kdb_set_current_task(struct task_struct *p)
1186{
1187	kdb_current_task = p;
1188
1189	if (kdb_task_has_cpu(p)) {
1190		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1191		return;
1192	}
1193	kdb_current_regs = NULL;
1194}
1195
1196static void drop_newline(char *buf)
1197{
1198	size_t len = strlen(buf);
1199
1200	if (len == 0)
1201		return;
1202	if (*(buf + len - 1) == '\n')
1203		*(buf + len - 1) = '\0';
1204}
1205
1206/*
1207 * kdb_local - The main code for kdb.  This routine is invoked on a
1208 *	specific processor, it is not global.  The main kdb() routine
1209 *	ensures that only one processor at a time is in this routine.
1210 *	This code is called with the real reason code on the first
1211 *	entry to a kdb session, thereafter it is called with reason
1212 *	SWITCH, even if the user goes back to the original cpu.
1213 * Inputs:
1214 *	reason		The reason KDB was invoked
1215 *	error		The hardware-defined error code
1216 *	regs		The exception frame at time of fault/breakpoint.
1217 *	db_result	Result code from the break or debug point.
1218 * Returns:
1219 *	0	KDB was invoked for an event which it wasn't responsible
1220 *	1	KDB handled the event for which it was invoked.
1221 *	KDB_CMD_GO	User typed 'go'.
1222 *	KDB_CMD_CPU	User switched to another cpu.
1223 *	KDB_CMD_SS	Single step.
1224 */
1225static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1226		     kdb_dbtrap_t db_result)
1227{
1228	char *cmdbuf;
1229	int diag;
1230	struct task_struct *kdb_current =
1231		kdb_curr_task(raw_smp_processor_id());
1232
1233	KDB_DEBUG_STATE("kdb_local 1", reason);
1234
1235	kdb_check_for_lockdown();
1236
1237	kdb_go_count = 0;
1238	if (reason == KDB_REASON_DEBUG) {
1239		/* special case below */
1240	} else {
1241		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1242			   kdb_current, kdb_current ? kdb_current->pid : 0);
1243#if defined(CONFIG_SMP)
1244		kdb_printf("on processor %d ", raw_smp_processor_id());
1245#endif
1246	}
1247
1248	switch (reason) {
1249	case KDB_REASON_DEBUG:
1250	{
1251		/*
1252		 * If re-entering kdb after a single step
1253		 * command, don't print the message.
1254		 */
1255		switch (db_result) {
1256		case KDB_DB_BPT:
1257			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1258				   kdb_current, kdb_current->pid);
1259#if defined(CONFIG_SMP)
1260			kdb_printf("on processor %d ", raw_smp_processor_id());
1261#endif
1262			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1263				   instruction_pointer(regs));
1264			break;
1265		case KDB_DB_SS:
1266			break;
1267		case KDB_DB_SSBPT:
1268			KDB_DEBUG_STATE("kdb_local 4", reason);
1269			return 1;	/* kdba_db_trap did the work */
1270		default:
1271			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1272				   db_result);
1273			break;
1274		}
1275
1276	}
1277		break;
1278	case KDB_REASON_ENTER:
1279		if (KDB_STATE(KEYBOARD))
1280			kdb_printf("due to Keyboard Entry\n");
1281		else
1282			kdb_printf("due to KDB_ENTER()\n");
1283		break;
1284	case KDB_REASON_KEYBOARD:
1285		KDB_STATE_SET(KEYBOARD);
1286		kdb_printf("due to Keyboard Entry\n");
1287		break;
1288	case KDB_REASON_ENTER_SLAVE:
1289		/* drop through, slaves only get released via cpu switch */
1290	case KDB_REASON_SWITCH:
1291		kdb_printf("due to cpu switch\n");
1292		break;
1293	case KDB_REASON_OOPS:
1294		kdb_printf("Oops: %s\n", kdb_diemsg);
1295		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1296			   instruction_pointer(regs));
1297		kdb_dumpregs(regs);
1298		break;
1299	case KDB_REASON_SYSTEM_NMI:
1300		kdb_printf("due to System NonMaskable Interrupt\n");
1301		break;
1302	case KDB_REASON_NMI:
1303		kdb_printf("due to NonMaskable Interrupt @ "
1304			   kdb_machreg_fmt "\n",
1305			   instruction_pointer(regs));
1306		break;
1307	case KDB_REASON_SSTEP:
1308	case KDB_REASON_BREAK:
1309		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1310			   reason == KDB_REASON_BREAK ?
1311			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1312		/*
1313		 * Determine if this breakpoint is one that we
1314		 * are interested in.
1315		 */
1316		if (db_result != KDB_DB_BPT) {
1317			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1318				   db_result);
1319			KDB_DEBUG_STATE("kdb_local 6", reason);
1320			return 0;	/* Not for us, dismiss it */
1321		}
1322		break;
1323	case KDB_REASON_RECURSE:
1324		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1325			   instruction_pointer(regs));
1326		break;
1327	default:
1328		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1329		KDB_DEBUG_STATE("kdb_local 8", reason);
1330		return 0;	/* Not for us, dismiss it */
1331	}
1332
1333	while (1) {
1334		/*
1335		 * Initialize pager context.
1336		 */
1337		kdb_nextline = 1;
1338		KDB_STATE_CLEAR(SUPPRESS);
1339		kdb_grepping_flag = 0;
1340		/* ensure the old search does not leak into '/' commands */
1341		kdb_grep_string[0] = '\0';
1342
1343		cmdbuf = cmd_cur;
1344		*cmdbuf = '\0';
1345		*(cmd_hist[cmd_head]) = '\0';
1346
1347do_full_getstr:
1348		/* PROMPT can only be set if we have MEM_READ permission. */
1349		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1350			 raw_smp_processor_id());
 
 
 
 
 
1351
1352		/*
1353		 * Fetch command from keyboard
1354		 */
1355		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1356		if (*cmdbuf != '\n') {
1357			if (*cmdbuf < 32) {
1358				if (cmdptr == cmd_head) {
1359					strscpy(cmd_hist[cmd_head], cmd_cur,
1360						CMD_BUFLEN);
1361					*(cmd_hist[cmd_head] +
1362					  strlen(cmd_hist[cmd_head])-1) = '\0';
1363				}
1364				if (!handle_ctrl_cmd(cmdbuf))
1365					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1366				cmdbuf = cmd_cur;
1367				goto do_full_getstr;
1368			} else {
1369				strscpy(cmd_hist[cmd_head], cmd_cur,
1370					CMD_BUFLEN);
1371			}
1372
1373			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1374			if (cmd_head == cmd_tail)
1375				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1376		}
1377
1378		cmdptr = cmd_head;
1379		diag = kdb_parse(cmdbuf);
1380		if (diag == KDB_NOTFOUND) {
1381			drop_newline(cmdbuf);
1382			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1383			diag = 0;
1384		}
1385		if (diag == KDB_CMD_GO
1386		 || diag == KDB_CMD_CPU
1387		 || diag == KDB_CMD_SS
1388		 || diag == KDB_CMD_KGDB)
1389			break;
1390
1391		if (diag)
1392			kdb_cmderror(diag);
1393	}
1394	KDB_DEBUG_STATE("kdb_local 9", diag);
1395	return diag;
1396}
1397
1398
1399/*
1400 * kdb_print_state - Print the state data for the current processor
1401 *	for debugging.
1402 * Inputs:
1403 *	text		Identifies the debug point
1404 *	value		Any integer value to be printed, e.g. reason code.
1405 */
1406void kdb_print_state(const char *text, int value)
1407{
1408	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1409		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1410		   kdb_state);
1411}
1412
1413/*
1414 * kdb_main_loop - After initial setup and assignment of the
1415 *	controlling cpu, all cpus are in this loop.  One cpu is in
1416 *	control and will issue the kdb prompt, the others will spin
1417 *	until 'go' or cpu switch.
1418 *
1419 *	To get a consistent view of the kernel stacks for all
1420 *	processes, this routine is invoked from the main kdb code via
1421 *	an architecture specific routine.  kdba_main_loop is
1422 *	responsible for making the kernel stacks consistent for all
1423 *	processes, there should be no difference between a blocked
1424 *	process and a running process as far as kdb is concerned.
1425 * Inputs:
1426 *	reason		The reason KDB was invoked
1427 *	error		The hardware-defined error code
1428 *	reason2		kdb's current reason code.
1429 *			Initially error but can change
1430 *			according to kdb state.
1431 *	db_result	Result code from break or debug point.
1432 *	regs		The exception frame at time of fault/breakpoint.
1433 *			should always be valid.
1434 * Returns:
1435 *	0	KDB was invoked for an event which it wasn't responsible
1436 *	1	KDB handled the event for which it was invoked.
1437 */
1438int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1439	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1440{
1441	int result = 1;
1442	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1443	while (1) {
1444		/*
1445		 * All processors except the one that is in control
1446		 * will spin here.
1447		 */
1448		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1449		while (KDB_STATE(HOLD_CPU)) {
1450			/* state KDB is turned off by kdb_cpu to see if the
1451			 * other cpus are still live, each cpu in this loop
1452			 * turns it back on.
1453			 */
1454			if (!KDB_STATE(KDB))
1455				KDB_STATE_SET(KDB);
1456		}
1457
1458		KDB_STATE_CLEAR(SUPPRESS);
1459		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1460		if (KDB_STATE(LEAVING))
1461			break;	/* Another cpu said 'go' */
1462		/* Still using kdb, this processor is in control */
1463		result = kdb_local(reason2, error, regs, db_result);
1464		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1465
1466		if (result == KDB_CMD_CPU)
1467			break;
1468
1469		if (result == KDB_CMD_SS) {
1470			KDB_STATE_SET(DOING_SS);
1471			break;
1472		}
1473
1474		if (result == KDB_CMD_KGDB) {
1475			if (!KDB_STATE(DOING_KGDB))
1476				kdb_printf("Entering please attach debugger "
1477					   "or use $D#44+ or $3#33\n");
1478			break;
1479		}
1480		if (result && result != 1 && result != KDB_CMD_GO)
1481			kdb_printf("\nUnexpected kdb_local return code %d\n",
1482				   result);
1483		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1484		break;
1485	}
1486	if (KDB_STATE(DOING_SS))
1487		KDB_STATE_CLEAR(SSBPT);
1488
1489	/* Clean up any keyboard devices before leaving */
1490	kdb_kbd_cleanup_state();
1491
1492	return result;
1493}
1494
1495/*
1496 * kdb_mdr - This function implements the guts of the 'mdr', memory
1497 * read command.
1498 *	mdr  <addr arg>,<byte count>
1499 * Inputs:
1500 *	addr	Start address
1501 *	count	Number of bytes
1502 * Returns:
1503 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1504 */
1505static int kdb_mdr(unsigned long addr, unsigned int count)
1506{
1507	unsigned char c;
1508	while (count--) {
1509		if (kdb_getarea(c, addr))
1510			return 0;
1511		kdb_printf("%02x", c);
1512		addr++;
1513	}
1514	kdb_printf("\n");
1515	return 0;
1516}
1517
1518/*
1519 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1520 *	'md8' 'mdr' and 'mds' commands.
1521 *
1522 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1523 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1524 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1525 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1526 *	mdr  <addr arg>,<byte count>
1527 */
1528static void kdb_md_line(const char *fmtstr, unsigned long addr,
1529			int symbolic, int nosect, int bytesperword,
1530			int num, int repeat, int phys)
1531{
1532	/* print just one line of data */
1533	kdb_symtab_t symtab;
1534	char cbuf[32];
1535	char *c = cbuf;
1536	int i;
1537	int j;
1538	unsigned long word;
1539
1540	memset(cbuf, '\0', sizeof(cbuf));
1541	if (phys)
1542		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1543	else
1544		kdb_printf(kdb_machreg_fmt0 " ", addr);
1545
1546	for (i = 0; i < num && repeat--; i++) {
1547		if (phys) {
1548			if (kdb_getphysword(&word, addr, bytesperword))
1549				break;
1550		} else if (kdb_getword(&word, addr, bytesperword))
1551			break;
1552		kdb_printf(fmtstr, word);
1553		if (symbolic)
1554			kdbnearsym(word, &symtab);
1555		else
1556			memset(&symtab, 0, sizeof(symtab));
1557		if (symtab.sym_name) {
1558			kdb_symbol_print(word, &symtab, 0);
1559			if (!nosect) {
1560				kdb_printf("\n");
1561				kdb_printf("                       %s %s "
1562					   kdb_machreg_fmt " "
1563					   kdb_machreg_fmt " "
1564					   kdb_machreg_fmt, symtab.mod_name,
1565					   symtab.sec_name, symtab.sec_start,
1566					   symtab.sym_start, symtab.sym_end);
1567			}
1568			addr += bytesperword;
1569		} else {
1570			union {
1571				u64 word;
1572				unsigned char c[8];
1573			} wc;
1574			unsigned char *cp;
1575#ifdef	__BIG_ENDIAN
1576			cp = wc.c + 8 - bytesperword;
1577#else
1578			cp = wc.c;
1579#endif
1580			wc.word = word;
1581#define printable_char(c) \
1582	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1583			for (j = 0; j < bytesperword; j++)
1584				*c++ = printable_char(*cp++);
1585			addr += bytesperword;
1586#undef printable_char
1587		}
1588	}
1589	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1590		   " ", cbuf);
1591}
1592
1593static int kdb_md(int argc, const char **argv)
1594{
1595	static unsigned long last_addr;
1596	static int last_radix, last_bytesperword, last_repeat;
1597	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1598	int nosect = 0;
1599	char fmtchar, fmtstr[64];
1600	unsigned long addr;
1601	unsigned long word;
1602	long offset = 0;
1603	int symbolic = 0;
1604	int valid = 0;
1605	int phys = 0;
1606	int raw = 0;
1607
1608	kdbgetintenv("MDCOUNT", &mdcount);
1609	kdbgetintenv("RADIX", &radix);
1610	kdbgetintenv("BYTESPERWORD", &bytesperword);
1611
1612	/* Assume 'md <addr>' and start with environment values */
1613	repeat = mdcount * 16 / bytesperword;
1614
1615	if (strcmp(argv[0], "mdr") == 0) {
1616		if (argc == 2 || (argc == 0 && last_addr != 0))
1617			valid = raw = 1;
1618		else
1619			return KDB_ARGCOUNT;
1620	} else if (isdigit(argv[0][2])) {
1621		bytesperword = (int)(argv[0][2] - '0');
1622		if (bytesperword == 0) {
1623			bytesperword = last_bytesperword;
1624			if (bytesperword == 0)
1625				bytesperword = 4;
1626		}
1627		last_bytesperword = bytesperword;
1628		repeat = mdcount * 16 / bytesperword;
1629		if (!argv[0][3])
1630			valid = 1;
1631		else if (argv[0][3] == 'c' && argv[0][4]) {
1632			char *p;
1633			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1634			mdcount = ((repeat * bytesperword) + 15) / 16;
1635			valid = !*p;
1636		}
1637		last_repeat = repeat;
1638	} else if (strcmp(argv[0], "md") == 0)
1639		valid = 1;
1640	else if (strcmp(argv[0], "mds") == 0)
1641		valid = 1;
1642	else if (strcmp(argv[0], "mdp") == 0) {
1643		phys = valid = 1;
1644	}
1645	if (!valid)
1646		return KDB_NOTFOUND;
1647
1648	if (argc == 0) {
1649		if (last_addr == 0)
1650			return KDB_ARGCOUNT;
1651		addr = last_addr;
1652		radix = last_radix;
1653		bytesperword = last_bytesperword;
1654		repeat = last_repeat;
1655		if (raw)
1656			mdcount = repeat;
1657		else
1658			mdcount = ((repeat * bytesperword) + 15) / 16;
1659	}
1660
1661	if (argc) {
1662		unsigned long val;
1663		int diag, nextarg = 1;
1664		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1665				     &offset, NULL);
1666		if (diag)
1667			return diag;
1668		if (argc > nextarg+2)
1669			return KDB_ARGCOUNT;
1670
1671		if (argc >= nextarg) {
1672			diag = kdbgetularg(argv[nextarg], &val);
1673			if (!diag) {
1674				mdcount = (int) val;
1675				if (raw)
1676					repeat = mdcount;
1677				else
1678					repeat = mdcount * 16 / bytesperword;
1679			}
1680		}
1681		if (argc >= nextarg+1) {
1682			diag = kdbgetularg(argv[nextarg+1], &val);
1683			if (!diag)
1684				radix = (int) val;
1685		}
1686	}
1687
1688	if (strcmp(argv[0], "mdr") == 0) {
1689		int ret;
1690		last_addr = addr;
1691		ret = kdb_mdr(addr, mdcount);
1692		last_addr += mdcount;
1693		last_repeat = mdcount;
1694		last_bytesperword = bytesperword; // to make REPEAT happy
1695		return ret;
1696	}
1697
1698	switch (radix) {
1699	case 10:
1700		fmtchar = 'd';
1701		break;
1702	case 16:
1703		fmtchar = 'x';
1704		break;
1705	case 8:
1706		fmtchar = 'o';
1707		break;
1708	default:
1709		return KDB_BADRADIX;
1710	}
1711
1712	last_radix = radix;
1713
1714	if (bytesperword > KDB_WORD_SIZE)
1715		return KDB_BADWIDTH;
1716
1717	switch (bytesperword) {
1718	case 8:
1719		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1720		break;
1721	case 4:
1722		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1723		break;
1724	case 2:
1725		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1726		break;
1727	case 1:
1728		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1729		break;
1730	default:
1731		return KDB_BADWIDTH;
1732	}
1733
1734	last_repeat = repeat;
1735	last_bytesperword = bytesperword;
1736
1737	if (strcmp(argv[0], "mds") == 0) {
1738		symbolic = 1;
1739		/* Do not save these changes as last_*, they are temporary mds
1740		 * overrides.
1741		 */
1742		bytesperword = KDB_WORD_SIZE;
1743		repeat = mdcount;
1744		kdbgetintenv("NOSECT", &nosect);
1745	}
1746
1747	/* Round address down modulo BYTESPERWORD */
1748
1749	addr &= ~(bytesperword-1);
1750
1751	while (repeat > 0) {
1752		unsigned long a;
1753		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1754
1755		if (KDB_FLAG(CMD_INTERRUPT))
1756			return 0;
1757		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1758			if (phys) {
1759				if (kdb_getphysword(&word, a, bytesperword)
1760						|| word)
1761					break;
1762			} else if (kdb_getword(&word, a, bytesperword) || word)
1763				break;
1764		}
1765		n = min(num, repeat);
1766		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1767			    num, repeat, phys);
1768		addr += bytesperword * n;
1769		repeat -= n;
1770		z = (z + num - 1) / num;
1771		if (z > 2) {
1772			int s = num * (z-2);
1773			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1774				   " zero suppressed\n",
1775				addr, addr + bytesperword * s - 1);
1776			addr += bytesperword * s;
1777			repeat -= s;
1778		}
1779	}
1780	last_addr = addr;
1781
1782	return 0;
1783}
1784
1785/*
1786 * kdb_mm - This function implements the 'mm' command.
1787 *	mm address-expression new-value
1788 * Remarks:
1789 *	mm works on machine words, mmW works on bytes.
1790 */
1791static int kdb_mm(int argc, const char **argv)
1792{
1793	int diag;
1794	unsigned long addr;
1795	long offset = 0;
1796	unsigned long contents;
1797	int nextarg;
1798	int width;
1799
1800	if (argv[0][2] && !isdigit(argv[0][2]))
1801		return KDB_NOTFOUND;
1802
1803	if (argc < 2)
1804		return KDB_ARGCOUNT;
1805
1806	nextarg = 1;
1807	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1808	if (diag)
1809		return diag;
1810
1811	if (nextarg > argc)
1812		return KDB_ARGCOUNT;
1813	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1814	if (diag)
1815		return diag;
1816
1817	if (nextarg != argc + 1)
1818		return KDB_ARGCOUNT;
1819
1820	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1821	diag = kdb_putword(addr, contents, width);
1822	if (diag)
1823		return diag;
1824
1825	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1826
1827	return 0;
1828}
1829
1830/*
1831 * kdb_go - This function implements the 'go' command.
1832 *	go [address-expression]
1833 */
1834static int kdb_go(int argc, const char **argv)
1835{
1836	unsigned long addr;
1837	int diag;
1838	int nextarg;
1839	long offset;
1840
1841	if (raw_smp_processor_id() != kdb_initial_cpu) {
1842		kdb_printf("go must execute on the entry cpu, "
1843			   "please use \"cpu %d\" and then execute go\n",
1844			   kdb_initial_cpu);
1845		return KDB_BADCPUNUM;
1846	}
1847	if (argc == 1) {
1848		nextarg = 1;
1849		diag = kdbgetaddrarg(argc, argv, &nextarg,
1850				     &addr, &offset, NULL);
1851		if (diag)
1852			return diag;
1853	} else if (argc) {
1854		return KDB_ARGCOUNT;
1855	}
1856
1857	diag = KDB_CMD_GO;
1858	if (KDB_FLAG(CATASTROPHIC)) {
1859		kdb_printf("Catastrophic error detected\n");
1860		kdb_printf("kdb_continue_catastrophic=%d, ",
1861			kdb_continue_catastrophic);
1862		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1863			kdb_printf("type go a second time if you really want "
1864				   "to continue\n");
1865			return 0;
1866		}
1867		if (kdb_continue_catastrophic == 2) {
1868			kdb_printf("forcing reboot\n");
1869			kdb_reboot(0, NULL);
1870		}
1871		kdb_printf("attempting to continue\n");
1872	}
1873	return diag;
1874}
1875
1876/*
1877 * kdb_rd - This function implements the 'rd' command.
1878 */
1879static int kdb_rd(int argc, const char **argv)
1880{
1881	int len = kdb_check_regs();
1882#if DBG_MAX_REG_NUM > 0
1883	int i;
1884	char *rname;
1885	int rsize;
1886	u64 reg64;
1887	u32 reg32;
1888	u16 reg16;
1889	u8 reg8;
1890
1891	if (len)
1892		return len;
1893
1894	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1895		rsize = dbg_reg_def[i].size * 2;
1896		if (rsize > 16)
1897			rsize = 2;
1898		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1899			len = 0;
1900			kdb_printf("\n");
1901		}
1902		if (len)
1903			len += kdb_printf("  ");
1904		switch(dbg_reg_def[i].size * 8) {
1905		case 8:
1906			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1907			if (!rname)
1908				break;
1909			len += kdb_printf("%s: %02x", rname, reg8);
1910			break;
1911		case 16:
1912			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1913			if (!rname)
1914				break;
1915			len += kdb_printf("%s: %04x", rname, reg16);
1916			break;
1917		case 32:
1918			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1919			if (!rname)
1920				break;
1921			len += kdb_printf("%s: %08x", rname, reg32);
1922			break;
1923		case 64:
1924			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1925			if (!rname)
1926				break;
1927			len += kdb_printf("%s: %016llx", rname, reg64);
1928			break;
1929		default:
1930			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1931		}
1932	}
1933	kdb_printf("\n");
1934#else
1935	if (len)
1936		return len;
1937
1938	kdb_dumpregs(kdb_current_regs);
1939#endif
1940	return 0;
1941}
1942
1943/*
1944 * kdb_rm - This function implements the 'rm' (register modify)  command.
1945 *	rm register-name new-contents
1946 * Remarks:
1947 *	Allows register modification with the same restrictions as gdb
1948 */
1949static int kdb_rm(int argc, const char **argv)
1950{
1951#if DBG_MAX_REG_NUM > 0
1952	int diag;
1953	const char *rname;
1954	int i;
1955	u64 reg64;
1956	u32 reg32;
1957	u16 reg16;
1958	u8 reg8;
1959
1960	if (argc != 2)
1961		return KDB_ARGCOUNT;
1962	/*
1963	 * Allow presence or absence of leading '%' symbol.
1964	 */
1965	rname = argv[1];
1966	if (*rname == '%')
1967		rname++;
1968
1969	diag = kdbgetu64arg(argv[2], &reg64);
1970	if (diag)
1971		return diag;
1972
1973	diag = kdb_check_regs();
1974	if (diag)
1975		return diag;
1976
1977	diag = KDB_BADREG;
1978	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1979		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1980			diag = 0;
1981			break;
1982		}
1983	}
1984	if (!diag) {
1985		switch(dbg_reg_def[i].size * 8) {
1986		case 8:
1987			reg8 = reg64;
1988			dbg_set_reg(i, &reg8, kdb_current_regs);
1989			break;
1990		case 16:
1991			reg16 = reg64;
1992			dbg_set_reg(i, &reg16, kdb_current_regs);
1993			break;
1994		case 32:
1995			reg32 = reg64;
1996			dbg_set_reg(i, &reg32, kdb_current_regs);
1997			break;
1998		case 64:
1999			dbg_set_reg(i, &reg64, kdb_current_regs);
2000			break;
2001		}
2002	}
2003	return diag;
2004#else
2005	kdb_printf("ERROR: Register set currently not implemented\n");
2006    return 0;
2007#endif
2008}
2009
2010#if defined(CONFIG_MAGIC_SYSRQ)
2011/*
2012 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
2013 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
2014 *		sr <magic-sysrq-code>
2015 */
2016static int kdb_sr(int argc, const char **argv)
2017{
2018	bool check_mask =
2019	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
2020
2021	if (argc != 1)
2022		return KDB_ARGCOUNT;
2023
2024	kdb_trap_printk++;
2025	__handle_sysrq(*argv[1], check_mask);
2026	kdb_trap_printk--;
2027
2028	return 0;
2029}
2030#endif	/* CONFIG_MAGIC_SYSRQ */
2031
2032/*
2033 * kdb_ef - This function implements the 'regs' (display exception
2034 *	frame) command.  This command takes an address and expects to
2035 *	find an exception frame at that address, formats and prints
2036 *	it.
2037 *		regs address-expression
2038 * Remarks:
2039 *	Not done yet.
2040 */
2041static int kdb_ef(int argc, const char **argv)
2042{
2043	int diag;
2044	unsigned long addr;
2045	long offset;
2046	int nextarg;
2047
2048	if (argc != 1)
2049		return KDB_ARGCOUNT;
2050
2051	nextarg = 1;
2052	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2053	if (diag)
2054		return diag;
2055	show_regs((struct pt_regs *)addr);
2056	return 0;
2057}
2058
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2059/*
2060 * kdb_env - This function implements the 'env' command.  Display the
2061 *	current environment variables.
2062 */
2063
2064static int kdb_env(int argc, const char **argv)
2065{
2066	kdb_printenv();
 
 
 
 
 
2067
2068	if (KDB_DEBUG(MASK))
2069		kdb_printf("KDBDEBUG=0x%x\n",
2070			(kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2071
2072	return 0;
2073}
2074
2075#ifdef CONFIG_PRINTK
2076/*
2077 * kdb_dmesg - This function implements the 'dmesg' command to display
2078 *	the contents of the syslog buffer.
2079 *		dmesg [lines] [adjust]
2080 */
2081static int kdb_dmesg(int argc, const char **argv)
2082{
2083	int diag;
2084	int logging;
2085	int lines = 0;
2086	int adjust = 0;
2087	int n = 0;
2088	int skip = 0;
2089	struct kmsg_dump_iter iter;
2090	size_t len;
2091	char buf[201];
2092
2093	if (argc > 2)
2094		return KDB_ARGCOUNT;
2095	if (argc) {
2096		char *cp;
2097		lines = simple_strtol(argv[1], &cp, 0);
2098		if (*cp)
2099			lines = 0;
2100		if (argc > 1) {
2101			adjust = simple_strtoul(argv[2], &cp, 0);
2102			if (*cp || adjust < 0)
2103				adjust = 0;
2104		}
2105	}
2106
2107	/* disable LOGGING if set */
2108	diag = kdbgetintenv("LOGGING", &logging);
2109	if (!diag && logging) {
2110		const char *setargs[] = { "set", "LOGGING", "0" };
2111		kdb_set(2, setargs);
2112	}
2113
2114	kmsg_dump_rewind(&iter);
2115	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2116		n++;
2117
2118	if (lines < 0) {
2119		if (adjust >= n)
2120			kdb_printf("buffer only contains %d lines, nothing "
2121				   "printed\n", n);
2122		else if (adjust - lines >= n)
2123			kdb_printf("buffer only contains %d lines, last %d "
2124				   "lines printed\n", n, n - adjust);
2125		skip = adjust;
2126		lines = abs(lines);
2127	} else if (lines > 0) {
2128		skip = n - lines - adjust;
2129		lines = abs(lines);
2130		if (adjust >= n) {
2131			kdb_printf("buffer only contains %d lines, "
2132				   "nothing printed\n", n);
2133			skip = n;
2134		} else if (skip < 0) {
2135			lines += skip;
2136			skip = 0;
2137			kdb_printf("buffer only contains %d lines, first "
2138				   "%d lines printed\n", n, lines);
2139		}
2140	} else {
2141		lines = n;
2142	}
2143
2144	if (skip >= n || skip < 0)
2145		return 0;
2146
2147	kmsg_dump_rewind(&iter);
2148	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2149		if (skip) {
2150			skip--;
2151			continue;
2152		}
2153		if (!lines--)
2154			break;
2155		if (KDB_FLAG(CMD_INTERRUPT))
2156			return 0;
2157
2158		kdb_printf("%.*s\n", (int)len - 1, buf);
2159	}
2160
2161	return 0;
2162}
2163#endif /* CONFIG_PRINTK */
2164
2165/* Make sure we balance enable/disable calls, must disable first. */
2166static atomic_t kdb_nmi_disabled;
2167
2168static int kdb_disable_nmi(int argc, const char *argv[])
2169{
2170	if (atomic_read(&kdb_nmi_disabled))
2171		return 0;
2172	atomic_set(&kdb_nmi_disabled, 1);
2173	arch_kgdb_ops.enable_nmi(0);
2174	return 0;
2175}
2176
2177static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2178{
2179	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2180		return -EINVAL;
2181	arch_kgdb_ops.enable_nmi(1);
2182	return 0;
2183}
2184
2185static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2186	.set = kdb_param_enable_nmi,
2187};
2188module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2189
2190/*
2191 * kdb_cpu - This function implements the 'cpu' command.
2192 *	cpu	[<cpunum>]
2193 * Returns:
2194 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2195 */
2196static void kdb_cpu_status(void)
2197{
2198	int i, start_cpu, first_print = 1;
2199	char state, prev_state = '?';
2200
2201	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2202	kdb_printf("Available cpus: ");
2203	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2204		if (!cpu_online(i)) {
2205			state = 'F';	/* cpu is offline */
2206		} else if (!kgdb_info[i].enter_kgdb) {
2207			state = 'D';	/* cpu is online but unresponsive */
2208		} else {
2209			state = ' ';	/* cpu is responding to kdb */
2210			if (kdb_task_state_char(KDB_TSK(i)) == '-')
2211				state = '-';	/* idle task */
2212		}
2213		if (state != prev_state) {
2214			if (prev_state != '?') {
2215				if (!first_print)
2216					kdb_printf(", ");
2217				first_print = 0;
2218				kdb_printf("%d", start_cpu);
2219				if (start_cpu < i-1)
2220					kdb_printf("-%d", i-1);
2221				if (prev_state != ' ')
2222					kdb_printf("(%c)", prev_state);
2223			}
2224			prev_state = state;
2225			start_cpu = i;
2226		}
2227	}
2228	/* print the trailing cpus, ignoring them if they are all offline */
2229	if (prev_state != 'F') {
2230		if (!first_print)
2231			kdb_printf(", ");
2232		kdb_printf("%d", start_cpu);
2233		if (start_cpu < i-1)
2234			kdb_printf("-%d", i-1);
2235		if (prev_state != ' ')
2236			kdb_printf("(%c)", prev_state);
2237	}
2238	kdb_printf("\n");
2239}
2240
2241static int kdb_cpu(int argc, const char **argv)
2242{
2243	unsigned long cpunum;
2244	int diag;
2245
2246	if (argc == 0) {
2247		kdb_cpu_status();
2248		return 0;
2249	}
2250
2251	if (argc != 1)
2252		return KDB_ARGCOUNT;
2253
2254	diag = kdbgetularg(argv[1], &cpunum);
2255	if (diag)
2256		return diag;
2257
2258	/*
2259	 * Validate cpunum
2260	 */
2261	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2262		return KDB_BADCPUNUM;
2263
2264	dbg_switch_cpu = cpunum;
2265
2266	/*
2267	 * Switch to other cpu
2268	 */
2269	return KDB_CMD_CPU;
2270}
2271
2272/* The user may not realize that ps/bta with no parameters does not print idle
2273 * or sleeping system daemon processes, so tell them how many were suppressed.
2274 */
2275void kdb_ps_suppressed(void)
2276{
2277	int idle = 0, daemon = 0;
 
 
2278	unsigned long cpu;
2279	const struct task_struct *p, *g;
2280	for_each_online_cpu(cpu) {
2281		p = kdb_curr_task(cpu);
2282		if (kdb_task_state(p, "-"))
2283			++idle;
2284	}
2285	for_each_process_thread(g, p) {
2286		if (kdb_task_state(p, "ims"))
2287			++daemon;
2288	}
2289	if (idle || daemon) {
2290		if (idle)
2291			kdb_printf("%d idle process%s (state -)%s\n",
2292				   idle, idle == 1 ? "" : "es",
2293				   daemon ? " and " : "");
2294		if (daemon)
2295			kdb_printf("%d sleeping system daemon (state [ims]) "
2296				   "process%s", daemon,
2297				   daemon == 1 ? "" : "es");
2298		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2299	}
2300}
2301
 
 
 
 
 
2302void kdb_ps1(const struct task_struct *p)
2303{
2304	int cpu;
2305	unsigned long tmp;
2306
2307	if (!p ||
2308	    copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2309		return;
2310
2311	cpu = kdb_process_cpu(p);
2312	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2313		   (void *)p, p->pid, p->parent->pid,
2314		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2315		   kdb_task_state_char(p),
2316		   (void *)(&p->thread),
2317		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2318		   p->comm);
2319	if (kdb_task_has_cpu(p)) {
2320		if (!KDB_TSK(cpu)) {
2321			kdb_printf("  Error: no saved data for this cpu\n");
2322		} else {
2323			if (KDB_TSK(cpu) != p)
2324				kdb_printf("  Error: does not match running "
2325				   "process table (0x%px)\n", KDB_TSK(cpu));
2326		}
2327	}
2328}
2329
2330/*
2331 * kdb_ps - This function implements the 'ps' command which shows a
2332 *	    list of the active processes.
2333 *
2334 * ps [<state_chars>]   Show processes, optionally selecting only those whose
2335 *                      state character is found in <state_chars>.
2336 */
2337static int kdb_ps(int argc, const char **argv)
2338{
2339	struct task_struct *g, *p;
2340	const char *mask;
2341	unsigned long cpu;
2342
2343	if (argc == 0)
2344		kdb_ps_suppressed();
2345	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2346		(int)(2*sizeof(void *))+2, "Task Addr",
2347		(int)(2*sizeof(void *))+2, "Thread");
2348	mask = argc ? argv[1] : kdbgetenv("PS");
2349	/* Run the active tasks first */
2350	for_each_online_cpu(cpu) {
2351		if (KDB_FLAG(CMD_INTERRUPT))
2352			return 0;
2353		p = kdb_curr_task(cpu);
2354		if (kdb_task_state(p, mask))
2355			kdb_ps1(p);
2356	}
2357	kdb_printf("\n");
2358	/* Now the real tasks */
2359	for_each_process_thread(g, p) {
2360		if (KDB_FLAG(CMD_INTERRUPT))
2361			return 0;
2362		if (kdb_task_state(p, mask))
2363			kdb_ps1(p);
2364	}
2365
2366	return 0;
2367}
2368
2369/*
2370 * kdb_pid - This function implements the 'pid' command which switches
2371 *	the currently active process.
2372 *		pid [<pid> | R]
2373 */
2374static int kdb_pid(int argc, const char **argv)
2375{
2376	struct task_struct *p;
2377	unsigned long val;
2378	int diag;
2379
2380	if (argc > 1)
2381		return KDB_ARGCOUNT;
2382
2383	if (argc) {
2384		if (strcmp(argv[1], "R") == 0) {
2385			p = KDB_TSK(kdb_initial_cpu);
2386		} else {
2387			diag = kdbgetularg(argv[1], &val);
2388			if (diag)
2389				return KDB_BADINT;
2390
2391			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2392			if (!p) {
2393				kdb_printf("No task with pid=%d\n", (pid_t)val);
2394				return 0;
2395			}
2396		}
2397		kdb_set_current_task(p);
2398	}
2399	kdb_printf("KDB current process is %s(pid=%d)\n",
2400		   kdb_current_task->comm,
2401		   kdb_current_task->pid);
2402
2403	return 0;
2404}
2405
2406static int kdb_kgdb(int argc, const char **argv)
2407{
2408	return KDB_CMD_KGDB;
2409}
2410
2411/*
2412 * kdb_help - This function implements the 'help' and '?' commands.
2413 */
2414static int kdb_help(int argc, const char **argv)
2415{
2416	kdbtab_t *kt;
 
2417
2418	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2419	kdb_printf("-----------------------------"
2420		   "-----------------------------\n");
2421	list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2422		char *space = "";
2423		if (KDB_FLAG(CMD_INTERRUPT))
2424			return 0;
2425		if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true))
 
 
2426			continue;
2427		if (strlen(kt->usage) > 20)
2428			space = "\n                                    ";
2429		kdb_printf("%-15.15s %-20s%s%s\n", kt->name,
2430			   kt->usage, space, kt->help);
2431	}
2432	return 0;
2433}
2434
2435/*
2436 * kdb_kill - This function implements the 'kill' commands.
2437 */
2438static int kdb_kill(int argc, const char **argv)
2439{
2440	long sig, pid;
2441	char *endp;
2442	struct task_struct *p;
2443
2444	if (argc != 2)
2445		return KDB_ARGCOUNT;
2446
2447	sig = simple_strtol(argv[1], &endp, 0);
2448	if (*endp)
2449		return KDB_BADINT;
2450	if ((sig >= 0) || !valid_signal(-sig)) {
2451		kdb_printf("Invalid signal parameter.<-signal>\n");
2452		return 0;
2453	}
2454	sig = -sig;
2455
2456	pid = simple_strtol(argv[2], &endp, 0);
2457	if (*endp)
2458		return KDB_BADINT;
2459	if (pid <= 0) {
2460		kdb_printf("Process ID must be large than 0.\n");
2461		return 0;
2462	}
2463
2464	/* Find the process. */
2465	p = find_task_by_pid_ns(pid, &init_pid_ns);
2466	if (!p) {
2467		kdb_printf("The specified process isn't found.\n");
2468		return 0;
2469	}
2470	p = p->group_leader;
2471	kdb_send_sig(p, sig);
2472	return 0;
2473}
2474
2475/*
2476 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2477 * I cannot call that code directly from kdb, it has an unconditional
2478 * cli()/sti() and calls routines that take locks which can stop the debugger.
2479 */
2480static void kdb_sysinfo(struct sysinfo *val)
2481{
2482	u64 uptime = ktime_get_mono_fast_ns();
2483
2484	memset(val, 0, sizeof(*val));
2485	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2486	val->loads[0] = avenrun[0];
2487	val->loads[1] = avenrun[1];
2488	val->loads[2] = avenrun[2];
2489	val->procs = nr_threads-1;
2490	si_meminfo(val);
2491
2492	return;
2493}
2494
2495/*
2496 * kdb_summary - This function implements the 'summary' command.
2497 */
2498static int kdb_summary(int argc, const char **argv)
2499{
2500	time64_t now;
 
2501	struct sysinfo val;
2502
2503	if (argc)
2504		return KDB_ARGCOUNT;
2505
2506	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2507	kdb_printf("release    %s\n", init_uts_ns.name.release);
2508	kdb_printf("version    %s\n", init_uts_ns.name.version);
2509	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2510	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2511	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2512
2513	now = __ktime_get_real_seconds();
2514	kdb_printf("date       %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
 
 
 
 
 
 
2515	kdb_sysinfo(&val);
2516	kdb_printf("uptime     ");
2517	if (val.uptime > (24*60*60)) {
2518		int days = val.uptime / (24*60*60);
2519		val.uptime %= (24*60*60);
2520		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2521	}
2522	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2523
2524	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2525		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2526		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2527		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2528
2529	/* Display in kilobytes */
2530#define K(x) ((x) << (PAGE_SHIFT - 10))
2531	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2532		   "Buffers:        %8lu kB\n",
2533		   K(val.totalram), K(val.freeram), K(val.bufferram));
2534	return 0;
2535}
2536
2537/*
2538 * kdb_per_cpu - This function implements the 'per_cpu' command.
2539 */
2540static int kdb_per_cpu(int argc, const char **argv)
2541{
2542	char fmtstr[64];
2543	int cpu, diag, nextarg = 1;
2544	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2545
2546	if (argc < 1 || argc > 3)
2547		return KDB_ARGCOUNT;
2548
2549	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2550	if (diag)
2551		return diag;
2552
2553	if (argc >= 2) {
2554		diag = kdbgetularg(argv[2], &bytesperword);
2555		if (diag)
2556			return diag;
2557	}
2558	if (!bytesperword)
2559		bytesperword = KDB_WORD_SIZE;
2560	else if (bytesperword > KDB_WORD_SIZE)
2561		return KDB_BADWIDTH;
2562	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2563	if (argc >= 3) {
2564		diag = kdbgetularg(argv[3], &whichcpu);
2565		if (diag)
2566			return diag;
2567		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2568			kdb_printf("cpu %ld is not online\n", whichcpu);
2569			return KDB_BADCPUNUM;
2570		}
2571	}
2572
2573	/* Most architectures use __per_cpu_offset[cpu], some use
2574	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2575	 */
2576#ifdef	__per_cpu_offset
2577#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2578#else
2579#ifdef	CONFIG_SMP
2580#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2581#else
2582#define KDB_PCU(cpu) 0
2583#endif
2584#endif
2585	for_each_online_cpu(cpu) {
2586		if (KDB_FLAG(CMD_INTERRUPT))
2587			return 0;
2588
2589		if (whichcpu != ~0UL && whichcpu != cpu)
2590			continue;
2591		addr = symaddr + KDB_PCU(cpu);
2592		diag = kdb_getword(&val, addr, bytesperword);
2593		if (diag) {
2594			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2595				   "read, diag=%d\n", cpu, addr, diag);
2596			continue;
2597		}
2598		kdb_printf("%5d ", cpu);
2599		kdb_md_line(fmtstr, addr,
2600			bytesperword == KDB_WORD_SIZE,
2601			1, bytesperword, 1, 1, 0);
2602	}
2603#undef KDB_PCU
2604	return 0;
2605}
2606
2607/*
2608 * display help for the use of cmd | grep pattern
2609 */
2610static int kdb_grep_help(int argc, const char **argv)
2611{
2612	kdb_printf("Usage of  cmd args | grep pattern:\n");
2613	kdb_printf("  Any command's output may be filtered through an ");
2614	kdb_printf("emulated 'pipe'.\n");
2615	kdb_printf("  'grep' is just a key word.\n");
2616	kdb_printf("  The pattern may include a very limited set of "
2617		   "metacharacters:\n");
2618	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2619	kdb_printf("  And if there are spaces in the pattern, you may "
2620		   "quote it:\n");
2621	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2622		   " or \"^pat tern$\"\n");
2623	return 0;
2624}
2625
2626/**
2627 * kdb_register() - This function is used to register a kernel debugger
2628 *                  command.
2629 * @cmd: pointer to kdb command
2630 *
2631 * Note that it's the job of the caller to keep the memory for the cmd
2632 * allocated until unregister is called.
 
 
 
 
2633 */
2634int kdb_register(kdbtab_t *cmd)
 
 
 
 
 
 
2635{
 
2636	kdbtab_t *kp;
2637
2638	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2639		if (strcmp(kp->name, cmd->name) == 0) {
2640			kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
2641				   cmd->name, cmd->func, cmd->help);
 
 
 
2642			return 1;
2643		}
2644	}
2645
2646	list_add_tail(&cmd->list_node, &kdb_cmds_head);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2647	return 0;
2648}
2649EXPORT_SYMBOL_GPL(kdb_register);
2650
2651/**
2652 * kdb_register_table() - This function is used to register a kdb command
2653 *                        table.
2654 * @kp: pointer to kdb command table
2655 * @len: length of kdb command table
 
 
 
 
 
 
 
2656 */
2657void kdb_register_table(kdbtab_t *kp, size_t len)
 
 
 
 
2658{
2659	while (len--) {
2660		list_add_tail(&kp->list_node, &kdb_cmds_head);
2661		kp++;
2662	}
2663}
 
2664
2665/**
2666 * kdb_unregister() - This function is used to unregister a kernel debugger
2667 *                    command. It is generally called when a module which
2668 *                    implements kdb command is unloaded.
2669 * @cmd: pointer to kdb command
 
 
 
2670 */
2671void kdb_unregister(kdbtab_t *cmd)
2672{
2673	list_del(&cmd->list_node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2674}
2675EXPORT_SYMBOL_GPL(kdb_unregister);
2676
2677static kdbtab_t maintab[] = {
2678	{	.name = "md",
2679		.func = kdb_md,
2680		.usage = "<vaddr>",
2681		.help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2682		.minlen = 1,
2683		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2684	},
2685	{	.name = "mdr",
2686		.func = kdb_md,
2687		.usage = "<vaddr> <bytes>",
2688		.help = "Display Raw Memory",
2689		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2690	},
2691	{	.name = "mdp",
2692		.func = kdb_md,
2693		.usage = "<paddr> <bytes>",
2694		.help = "Display Physical Memory",
2695		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2696	},
2697	{	.name = "mds",
2698		.func = kdb_md,
2699		.usage = "<vaddr>",
2700		.help = "Display Memory Symbolically",
2701		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2702	},
2703	{	.name = "mm",
2704		.func = kdb_mm,
2705		.usage = "<vaddr> <contents>",
2706		.help = "Modify Memory Contents",
2707		.flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2708	},
2709	{	.name = "go",
2710		.func = kdb_go,
2711		.usage = "[<vaddr>]",
2712		.help = "Continue Execution",
2713		.minlen = 1,
2714		.flags = KDB_ENABLE_REG_WRITE |
2715			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2716	},
2717	{	.name = "rd",
2718		.func = kdb_rd,
2719		.usage = "",
2720		.help = "Display Registers",
2721		.flags = KDB_ENABLE_REG_READ,
2722	},
2723	{	.name = "rm",
2724		.func = kdb_rm,
2725		.usage = "<reg> <contents>",
2726		.help = "Modify Registers",
2727		.flags = KDB_ENABLE_REG_WRITE,
2728	},
2729	{	.name = "ef",
2730		.func = kdb_ef,
2731		.usage = "<vaddr>",
2732		.help = "Display exception frame",
2733		.flags = KDB_ENABLE_MEM_READ,
2734	},
2735	{	.name = "bt",
2736		.func = kdb_bt,
2737		.usage = "[<vaddr>]",
2738		.help = "Stack traceback",
2739		.minlen = 1,
2740		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2741	},
2742	{	.name = "btp",
2743		.func = kdb_bt,
2744		.usage = "<pid>",
2745		.help = "Display stack for process <pid>",
2746		.flags = KDB_ENABLE_INSPECT,
2747	},
2748	{	.name = "bta",
2749		.func = kdb_bt,
2750		.usage = "[<state_chars>|A]",
2751		.help = "Backtrace all processes whose state matches",
2752		.flags = KDB_ENABLE_INSPECT,
2753	},
2754	{	.name = "btc",
2755		.func = kdb_bt,
2756		.usage = "",
2757		.help = "Backtrace current process on each cpu",
2758		.flags = KDB_ENABLE_INSPECT,
2759	},
2760	{	.name = "btt",
2761		.func = kdb_bt,
2762		.usage = "<vaddr>",
2763		.help = "Backtrace process given its struct task address",
2764		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2765	},
2766	{	.name = "env",
2767		.func = kdb_env,
2768		.usage = "",
2769		.help = "Show environment variables",
2770		.flags = KDB_ENABLE_ALWAYS_SAFE,
2771	},
2772	{	.name = "set",
2773		.func = kdb_set,
2774		.usage = "",
2775		.help = "Set environment variables",
2776		.flags = KDB_ENABLE_ALWAYS_SAFE,
2777	},
2778	{	.name = "help",
2779		.func = kdb_help,
2780		.usage = "",
2781		.help = "Display Help Message",
2782		.minlen = 1,
2783		.flags = KDB_ENABLE_ALWAYS_SAFE,
2784	},
2785	{	.name = "?",
2786		.func = kdb_help,
2787		.usage = "",
2788		.help = "Display Help Message",
2789		.flags = KDB_ENABLE_ALWAYS_SAFE,
2790	},
2791	{	.name = "cpu",
2792		.func = kdb_cpu,
2793		.usage = "<cpunum>",
2794		.help = "Switch to new cpu",
2795		.flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2796	},
2797	{	.name = "kgdb",
2798		.func = kdb_kgdb,
2799		.usage = "",
2800		.help = "Enter kgdb mode",
2801		.flags = 0,
2802	},
2803	{	.name = "ps",
2804		.func = kdb_ps,
2805		.usage = "[<state_chars>|A]",
2806		.help = "Display active task list",
2807		.flags = KDB_ENABLE_INSPECT,
2808	},
2809	{	.name = "pid",
2810		.func = kdb_pid,
2811		.usage = "<pidnum>",
2812		.help = "Switch to another task",
2813		.flags = KDB_ENABLE_INSPECT,
2814	},
2815	{	.name = "reboot",
2816		.func = kdb_reboot,
2817		.usage = "",
2818		.help = "Reboot the machine immediately",
2819		.flags = KDB_ENABLE_REBOOT,
2820	},
2821#if defined(CONFIG_MODULES)
2822	{	.name = "lsmod",
2823		.func = kdb_lsmod,
2824		.usage = "",
2825		.help = "List loaded kernel modules",
2826		.flags = KDB_ENABLE_INSPECT,
2827	},
2828#endif
2829#if defined(CONFIG_MAGIC_SYSRQ)
2830	{	.name = "sr",
2831		.func = kdb_sr,
2832		.usage = "<key>",
2833		.help = "Magic SysRq key",
2834		.flags = KDB_ENABLE_ALWAYS_SAFE,
2835	},
2836#endif
2837#if defined(CONFIG_PRINTK)
2838	{	.name = "dmesg",
2839		.func = kdb_dmesg,
2840		.usage = "[lines]",
2841		.help = "Display syslog buffer",
2842		.flags = KDB_ENABLE_ALWAYS_SAFE,
2843	},
2844#endif
2845	{	.name = "defcmd",
2846		.func = kdb_defcmd,
2847		.usage = "name \"usage\" \"help\"",
2848		.help = "Define a set of commands, down to endefcmd",
2849		/*
2850		 * Macros are always safe because when executed each
2851		 * internal command re-enters kdb_parse() and is safety
2852		 * checked individually.
2853		 */
2854		.flags = KDB_ENABLE_ALWAYS_SAFE,
2855	},
2856	{	.name = "kill",
2857		.func = kdb_kill,
2858		.usage = "<-signal> <pid>",
2859		.help = "Send a signal to a process",
2860		.flags = KDB_ENABLE_SIGNAL,
2861	},
2862	{	.name = "summary",
2863		.func = kdb_summary,
2864		.usage = "",
2865		.help = "Summarize the system",
2866		.minlen = 4,
2867		.flags = KDB_ENABLE_ALWAYS_SAFE,
2868	},
2869	{	.name = "per_cpu",
2870		.func = kdb_per_cpu,
2871		.usage = "<sym> [<bytes>] [<cpu>]",
2872		.help = "Display per_cpu variables",
2873		.minlen = 3,
2874		.flags = KDB_ENABLE_MEM_READ,
2875	},
2876	{	.name = "grephelp",
2877		.func = kdb_grep_help,
2878		.usage = "",
2879		.help = "Display help on | grep",
2880		.flags = KDB_ENABLE_ALWAYS_SAFE,
2881	},
2882};
2883
2884static kdbtab_t nmicmd = {
2885	.name = "disable_nmi",
2886	.func = kdb_disable_nmi,
2887	.usage = "",
2888	.help = "Disable NMI entry to KDB",
2889	.flags = KDB_ENABLE_ALWAYS_SAFE,
2890};
2891
2892/* Initialize the kdb command table. */
2893static void __init kdb_inittab(void)
2894{
2895	kdb_register_table(maintab, ARRAY_SIZE(maintab));
2896	if (arch_kgdb_ops.enable_nmi)
2897		kdb_register_table(&nmicmd, 1);
2898}
2899
2900/* Execute any commands defined in kdb_cmds.  */
2901static void __init kdb_cmd_init(void)
2902{
2903	int i, diag;
2904	for (i = 0; kdb_cmds[i]; ++i) {
2905		diag = kdb_parse(kdb_cmds[i]);
2906		if (diag)
2907			kdb_printf("kdb command %s failed, kdb diag %d\n",
2908				kdb_cmds[i], diag);
2909	}
2910	if (defcmd_in_progress) {
2911		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2912		kdb_parse("endefcmd");
2913	}
2914}
2915
2916/* Initialize kdb_printf, breakpoint tables and kdb state */
2917void __init kdb_init(int lvl)
2918{
2919	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2920	int i;
2921
2922	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2923		return;
2924	for (i = kdb_init_lvl; i < lvl; i++) {
2925		switch (i) {
2926		case KDB_NOT_INITIALIZED:
2927			kdb_inittab();		/* Initialize Command Table */
2928			kdb_initbptab();	/* Initialize Breakpoints */
2929			break;
2930		case KDB_INIT_EARLY:
2931			kdb_cmd_init();		/* Build kdb_cmds tables */
2932			break;
2933		}
2934	}
2935	kdb_init_lvl = lvl;
2936}
v5.4
   1/*
   2 * Kernel Debugger Architecture Independent Main Code
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
   9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
  10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
  11 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
  12 */
  13
  14#include <linux/ctype.h>
  15#include <linux/types.h>
  16#include <linux/string.h>
  17#include <linux/kernel.h>
  18#include <linux/kmsg_dump.h>
  19#include <linux/reboot.h>
  20#include <linux/sched.h>
  21#include <linux/sched/loadavg.h>
  22#include <linux/sched/stat.h>
  23#include <linux/sched/debug.h>
  24#include <linux/sysrq.h>
  25#include <linux/smp.h>
  26#include <linux/utsname.h>
  27#include <linux/vmalloc.h>
  28#include <linux/atomic.h>
  29#include <linux/module.h>
  30#include <linux/moduleparam.h>
  31#include <linux/mm.h>
  32#include <linux/init.h>
  33#include <linux/kallsyms.h>
  34#include <linux/kgdb.h>
  35#include <linux/kdb.h>
  36#include <linux/notifier.h>
  37#include <linux/interrupt.h>
  38#include <linux/delay.h>
  39#include <linux/nmi.h>
  40#include <linux/time.h>
  41#include <linux/ptrace.h>
  42#include <linux/sysctl.h>
  43#include <linux/cpu.h>
  44#include <linux/kdebug.h>
  45#include <linux/proc_fs.h>
  46#include <linux/uaccess.h>
  47#include <linux/slab.h>
 
  48#include "kdb_private.h"
  49
  50#undef	MODULE_PARAM_PREFIX
  51#define	MODULE_PARAM_PREFIX "kdb."
  52
  53static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  54module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  55
  56char kdb_grep_string[KDB_GREP_STRLEN];
  57int kdb_grepping_flag;
  58EXPORT_SYMBOL(kdb_grepping_flag);
  59int kdb_grep_leading;
  60int kdb_grep_trailing;
  61
  62/*
  63 * Kernel debugger state flags
  64 */
  65int kdb_flags;
  66
  67/*
  68 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  69 * single thread processors through the kernel debugger.
  70 */
  71int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  72int kdb_nextline = 1;
  73int kdb_state;			/* General KDB state */
  74
  75struct task_struct *kdb_current_task;
  76EXPORT_SYMBOL(kdb_current_task);
  77struct pt_regs *kdb_current_regs;
  78
  79const char *kdb_diemsg;
  80static int kdb_go_count;
  81#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
  82static unsigned int kdb_continue_catastrophic =
  83	CONFIG_KDB_CONTINUE_CATASTROPHIC;
  84#else
  85static unsigned int kdb_continue_catastrophic;
  86#endif
  87
  88/* kdb_commands describes the available commands. */
  89static kdbtab_t *kdb_commands;
  90#define KDB_BASE_CMD_MAX 50
  91static int kdb_max_commands = KDB_BASE_CMD_MAX;
  92static kdbtab_t kdb_base_commands[KDB_BASE_CMD_MAX];
  93#define for_each_kdbcmd(cmd, num)					\
  94	for ((cmd) = kdb_base_commands, (num) = 0;			\
  95	     num < kdb_max_commands;					\
  96	     num++, num == KDB_BASE_CMD_MAX ? cmd = kdb_commands : cmd++)
  97
  98typedef struct _kdbmsg {
  99	int	km_diag;	/* kdb diagnostic */
 100	char	*km_msg;	/* Corresponding message text */
 101} kdbmsg_t;
 102
 103#define KDBMSG(msgnum, text) \
 104	{ KDB_##msgnum, text }
 105
 106static kdbmsg_t kdbmsgs[] = {
 107	KDBMSG(NOTFOUND, "Command Not Found"),
 108	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 109	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 110	       "8 is only allowed on 64 bit systems"),
 111	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 112	KDBMSG(NOTENV, "Cannot find environment variable"),
 113	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 114	KDBMSG(NOTIMP, "Command not implemented"),
 115	KDBMSG(ENVFULL, "Environment full"),
 116	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 117	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 118#ifdef CONFIG_CPU_XSCALE
 119	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 120#else
 121	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 122#endif
 123	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 124	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 125	KDBMSG(BADMODE, "Invalid IDMODE"),
 126	KDBMSG(BADINT, "Illegal numeric value"),
 127	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 128	KDBMSG(BADREG, "Invalid register name"),
 129	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 130	KDBMSG(BADLENGTH, "Invalid length field"),
 131	KDBMSG(NOBP, "No Breakpoint exists"),
 132	KDBMSG(BADADDR, "Invalid address"),
 133	KDBMSG(NOPERM, "Permission denied"),
 134};
 135#undef KDBMSG
 136
 137static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 138
 139
 140/*
 141 * Initial environment.   This is all kept static and local to
 142 * this file.   We don't want to rely on the memory allocation
 143 * mechanisms in the kernel, so we use a very limited allocate-only
 144 * heap for new and altered environment variables.  The entire
 145 * environment is limited to a fixed number of entries (add more
 146 * to __env[] if required) and a fixed amount of heap (add more to
 147 * KDB_ENVBUFSIZE if required).
 148 */
 149
 150static char *__env[] = {
 151#if defined(CONFIG_SMP)
 152 "PROMPT=[%d]kdb> ",
 153#else
 154 "PROMPT=kdb> ",
 155#endif
 156 "MOREPROMPT=more> ",
 157 "RADIX=16",
 158 "MDCOUNT=8",			/* lines of md output */
 159 KDB_PLATFORM_ENV,
 160 "DTABCOUNT=30",
 161 "NOSECT=1",
 162 (char *)0,
 163 (char *)0,
 164 (char *)0,
 165 (char *)0,
 166 (char *)0,
 167 (char *)0,
 168 (char *)0,
 169 (char *)0,
 170 (char *)0,
 171 (char *)0,
 172 (char *)0,
 173 (char *)0,
 174 (char *)0,
 175 (char *)0,
 176 (char *)0,
 177 (char *)0,
 178 (char *)0,
 179 (char *)0,
 180 (char *)0,
 181 (char *)0,
 182 (char *)0,
 183 (char *)0,
 184 (char *)0,
 185 (char *)0,
 186};
 187
 188static const int __nenv = ARRAY_SIZE(__env);
 189
 190struct task_struct *kdb_curr_task(int cpu)
 191{
 192	struct task_struct *p = curr_task(cpu);
 193#ifdef	_TIF_MCA_INIT
 194	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 195		p = krp->p;
 196#endif
 197	return p;
 198}
 199
 200/*
 201 * Check whether the flags of the current command and the permissions
 202 * of the kdb console has allow a command to be run.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 203 */
 204static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 205				   bool no_args)
 206{
 207	/* permissions comes from userspace so needs massaging slightly */
 208	permissions &= KDB_ENABLE_MASK;
 209	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 210
 211	/* some commands change group when launched with no arguments */
 212	if (no_args)
 213		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 214
 215	flags |= KDB_ENABLE_ALL;
 216
 217	return permissions & flags;
 218}
 219
 220/*
 221 * kdbgetenv - This function will return the character string value of
 222 *	an environment variable.
 223 * Parameters:
 224 *	match	A character string representing an environment variable.
 225 * Returns:
 226 *	NULL	No environment variable matches 'match'
 227 *	char*	Pointer to string value of environment variable.
 228 */
 229char *kdbgetenv(const char *match)
 230{
 231	char **ep = __env;
 232	int matchlen = strlen(match);
 233	int i;
 234
 235	for (i = 0; i < __nenv; i++) {
 236		char *e = *ep++;
 237
 238		if (!e)
 239			continue;
 240
 241		if ((strncmp(match, e, matchlen) == 0)
 242		 && ((e[matchlen] == '\0')
 243		   || (e[matchlen] == '='))) {
 244			char *cp = strchr(e, '=');
 245			return cp ? ++cp : "";
 246		}
 247	}
 248	return NULL;
 249}
 250
 251/*
 252 * kdballocenv - This function is used to allocate bytes for
 253 *	environment entries.
 254 * Parameters:
 255 *	match	A character string representing a numeric value
 256 * Outputs:
 257 *	*value  the unsigned long representation of the env variable 'match'
 258 * Returns:
 259 *	Zero on success, a kdb diagnostic on failure.
 
 260 * Remarks:
 261 *	We use a static environment buffer (envbuffer) to hold the values
 262 *	of dynamically generated environment variables (see kdb_set).  Buffer
 263 *	space once allocated is never free'd, so over time, the amount of space
 264 *	(currently 512 bytes) will be exhausted if env variables are changed
 265 *	frequently.
 266 */
 267static char *kdballocenv(size_t bytes)
 268{
 269#define	KDB_ENVBUFSIZE	512
 270	static char envbuffer[KDB_ENVBUFSIZE];
 271	static int envbufsize;
 272	char *ep = NULL;
 273
 274	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 275		ep = &envbuffer[envbufsize];
 276		envbufsize += bytes;
 277	}
 278	return ep;
 279}
 280
 281/*
 282 * kdbgetulenv - This function will return the value of an unsigned
 283 *	long-valued environment variable.
 284 * Parameters:
 285 *	match	A character string representing a numeric value
 286 * Outputs:
 287 *	*value  the unsigned long represntation of the env variable 'match'
 288 * Returns:
 289 *	Zero on success, a kdb diagnostic on failure.
 290 */
 291static int kdbgetulenv(const char *match, unsigned long *value)
 292{
 293	char *ep;
 294
 295	ep = kdbgetenv(match);
 296	if (!ep)
 297		return KDB_NOTENV;
 298	if (strlen(ep) == 0)
 299		return KDB_NOENVVALUE;
 300
 301	*value = simple_strtoul(ep, NULL, 0);
 302
 303	return 0;
 304}
 305
 306/*
 307 * kdbgetintenv - This function will return the value of an
 308 *	integer-valued environment variable.
 309 * Parameters:
 310 *	match	A character string representing an integer-valued env variable
 311 * Outputs:
 312 *	*value  the integer representation of the environment variable 'match'
 313 * Returns:
 314 *	Zero on success, a kdb diagnostic on failure.
 315 */
 316int kdbgetintenv(const char *match, int *value)
 317{
 318	unsigned long val;
 319	int diag;
 320
 321	diag = kdbgetulenv(match, &val);
 322	if (!diag)
 323		*value = (int) val;
 324	return diag;
 325}
 326
 327/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 328 * kdbgetularg - This function will convert a numeric string into an
 329 *	unsigned long value.
 330 * Parameters:
 331 *	arg	A character string representing a numeric value
 332 * Outputs:
 333 *	*value  the unsigned long represntation of arg.
 334 * Returns:
 335 *	Zero on success, a kdb diagnostic on failure.
 336 */
 337int kdbgetularg(const char *arg, unsigned long *value)
 338{
 339	char *endp;
 340	unsigned long val;
 341
 342	val = simple_strtoul(arg, &endp, 0);
 343
 344	if (endp == arg) {
 345		/*
 346		 * Also try base 16, for us folks too lazy to type the
 347		 * leading 0x...
 348		 */
 349		val = simple_strtoul(arg, &endp, 16);
 350		if (endp == arg)
 351			return KDB_BADINT;
 352	}
 353
 354	*value = val;
 355
 356	return 0;
 357}
 358
 359int kdbgetu64arg(const char *arg, u64 *value)
 360{
 361	char *endp;
 362	u64 val;
 363
 364	val = simple_strtoull(arg, &endp, 0);
 365
 366	if (endp == arg) {
 367
 368		val = simple_strtoull(arg, &endp, 16);
 369		if (endp == arg)
 370			return KDB_BADINT;
 371	}
 372
 373	*value = val;
 374
 375	return 0;
 376}
 377
 378/*
 379 * kdb_set - This function implements the 'set' command.  Alter an
 380 *	existing environment variable or create a new one.
 381 */
 382int kdb_set(int argc, const char **argv)
 383{
 384	int i;
 385	char *ep;
 386	size_t varlen, vallen;
 387
 388	/*
 389	 * we can be invoked two ways:
 390	 *   set var=value    argv[1]="var", argv[2]="value"
 391	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 392	 * - if the latter, shift 'em down.
 393	 */
 394	if (argc == 3) {
 395		argv[2] = argv[3];
 396		argc--;
 397	}
 398
 399	if (argc != 2)
 400		return KDB_ARGCOUNT;
 401
 402	/*
 
 
 
 
 
 
 
 403	 * Check for internal variables
 404	 */
 405	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 406		unsigned int debugflags;
 407		char *cp;
 408
 409		debugflags = simple_strtoul(argv[2], &cp, 0);
 410		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 411			kdb_printf("kdb: illegal debug flags '%s'\n",
 412				    argv[2]);
 413			return 0;
 414		}
 415		kdb_flags = (kdb_flags &
 416			     ~(KDB_DEBUG_FLAG_MASK << KDB_DEBUG_FLAG_SHIFT))
 417			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 418
 419		return 0;
 420	}
 421
 422	/*
 423	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 424	 * name, argv[2] = value.
 425	 */
 426	varlen = strlen(argv[1]);
 427	vallen = strlen(argv[2]);
 428	ep = kdballocenv(varlen + vallen + 2);
 429	if (ep == (char *)0)
 430		return KDB_ENVBUFFULL;
 431
 432	sprintf(ep, "%s=%s", argv[1], argv[2]);
 433
 434	ep[varlen+vallen+1] = '\0';
 435
 436	for (i = 0; i < __nenv; i++) {
 437		if (__env[i]
 438		 && ((strncmp(__env[i], argv[1], varlen) == 0)
 439		   && ((__env[i][varlen] == '\0')
 440		    || (__env[i][varlen] == '=')))) {
 441			__env[i] = ep;
 442			return 0;
 443		}
 444	}
 445
 446	/*
 447	 * Wasn't existing variable.  Fit into slot.
 448	 */
 449	for (i = 0; i < __nenv-1; i++) {
 450		if (__env[i] == (char *)0) {
 451			__env[i] = ep;
 452			return 0;
 453		}
 454	}
 455
 456	return KDB_ENVFULL;
 457}
 458
 459static int kdb_check_regs(void)
 460{
 461	if (!kdb_current_regs) {
 462		kdb_printf("No current kdb registers."
 463			   "  You may need to select another task\n");
 464		return KDB_BADREG;
 465	}
 466	return 0;
 467}
 468
 469/*
 470 * kdbgetaddrarg - This function is responsible for parsing an
 471 *	address-expression and returning the value of the expression,
 472 *	symbol name, and offset to the caller.
 473 *
 474 *	The argument may consist of a numeric value (decimal or
 475 *	hexidecimal), a symbol name, a register name (preceded by the
 476 *	percent sign), an environment variable with a numeric value
 477 *	(preceded by a dollar sign) or a simple arithmetic expression
 478 *	consisting of a symbol name, +/-, and a numeric constant value
 479 *	(offset).
 480 * Parameters:
 481 *	argc	- count of arguments in argv
 482 *	argv	- argument vector
 483 *	*nextarg - index to next unparsed argument in argv[]
 484 *	regs	- Register state at time of KDB entry
 485 * Outputs:
 486 *	*value	- receives the value of the address-expression
 487 *	*offset - receives the offset specified, if any
 488 *	*name   - receives the symbol name, if any
 489 *	*nextarg - index to next unparsed argument in argv[]
 490 * Returns:
 491 *	zero is returned on success, a kdb diagnostic code is
 492 *      returned on error.
 493 */
 494int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 495		  unsigned long *value,  long *offset,
 496		  char **name)
 497{
 498	unsigned long addr;
 499	unsigned long off = 0;
 500	int positive;
 501	int diag;
 502	int found = 0;
 503	char *symname;
 504	char symbol = '\0';
 505	char *cp;
 506	kdb_symtab_t symtab;
 507
 508	/*
 509	 * If the enable flags prohibit both arbitrary memory access
 510	 * and flow control then there are no reasonable grounds to
 511	 * provide symbol lookup.
 512	 */
 513	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 514			     kdb_cmd_enabled, false))
 515		return KDB_NOPERM;
 516
 517	/*
 518	 * Process arguments which follow the following syntax:
 519	 *
 520	 *  symbol | numeric-address [+/- numeric-offset]
 521	 *  %register
 522	 *  $environment-variable
 523	 */
 524
 525	if (*nextarg > argc)
 526		return KDB_ARGCOUNT;
 527
 528	symname = (char *)argv[*nextarg];
 529
 530	/*
 531	 * If there is no whitespace between the symbol
 532	 * or address and the '+' or '-' symbols, we
 533	 * remember the character and replace it with a
 534	 * null so the symbol/value can be properly parsed
 535	 */
 536	cp = strpbrk(symname, "+-");
 537	if (cp != NULL) {
 538		symbol = *cp;
 539		*cp++ = '\0';
 540	}
 541
 542	if (symname[0] == '$') {
 543		diag = kdbgetulenv(&symname[1], &addr);
 544		if (diag)
 545			return diag;
 546	} else if (symname[0] == '%') {
 547		diag = kdb_check_regs();
 548		if (diag)
 549			return diag;
 550		/* Implement register values with % at a later time as it is
 551		 * arch optional.
 552		 */
 553		return KDB_NOTIMP;
 554	} else {
 555		found = kdbgetsymval(symname, &symtab);
 556		if (found) {
 557			addr = symtab.sym_start;
 558		} else {
 559			diag = kdbgetularg(argv[*nextarg], &addr);
 560			if (diag)
 561				return diag;
 562		}
 563	}
 564
 565	if (!found)
 566		found = kdbnearsym(addr, &symtab);
 567
 568	(*nextarg)++;
 569
 570	if (name)
 571		*name = symname;
 572	if (value)
 573		*value = addr;
 574	if (offset && name && *name)
 575		*offset = addr - symtab.sym_start;
 576
 577	if ((*nextarg > argc)
 578	 && (symbol == '\0'))
 579		return 0;
 580
 581	/*
 582	 * check for +/- and offset
 583	 */
 584
 585	if (symbol == '\0') {
 586		if ((argv[*nextarg][0] != '+')
 587		 && (argv[*nextarg][0] != '-')) {
 588			/*
 589			 * Not our argument.  Return.
 590			 */
 591			return 0;
 592		} else {
 593			positive = (argv[*nextarg][0] == '+');
 594			(*nextarg)++;
 595		}
 596	} else
 597		positive = (symbol == '+');
 598
 599	/*
 600	 * Now there must be an offset!
 601	 */
 602	if ((*nextarg > argc)
 603	 && (symbol == '\0')) {
 604		return KDB_INVADDRFMT;
 605	}
 606
 607	if (!symbol) {
 608		cp = (char *)argv[*nextarg];
 609		(*nextarg)++;
 610	}
 611
 612	diag = kdbgetularg(cp, &off);
 613	if (diag)
 614		return diag;
 615
 616	if (!positive)
 617		off = -off;
 618
 619	if (offset)
 620		*offset += off;
 621
 622	if (value)
 623		*value += off;
 624
 625	return 0;
 626}
 627
 628static void kdb_cmderror(int diag)
 629{
 630	int i;
 631
 632	if (diag >= 0) {
 633		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 634		return;
 635	}
 636
 637	for (i = 0; i < __nkdb_err; i++) {
 638		if (kdbmsgs[i].km_diag == diag) {
 639			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 640			return;
 641		}
 642	}
 643
 644	kdb_printf("Unknown diag %d\n", -diag);
 645}
 646
 647/*
 648 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 649 *	command which defines one command as a set of other commands,
 650 *	terminated by endefcmd.  kdb_defcmd processes the initial
 651 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 652 *	the following commands until 'endefcmd'.
 653 * Inputs:
 654 *	argc	argument count
 655 *	argv	argument vector
 656 * Returns:
 657 *	zero for success, a kdb diagnostic if error
 658 */
 659struct defcmd_set {
 660	int count;
 661	bool usable;
 662	char *name;
 663	char *usage;
 664	char *help;
 665	char **command;
 666};
 667static struct defcmd_set *defcmd_set;
 668static int defcmd_set_count;
 
 
 
 
 
 669static bool defcmd_in_progress;
 670
 671/* Forward references */
 672static int kdb_exec_defcmd(int argc, const char **argv);
 673
 674static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 675{
 676	struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
 677	char **save_command = s->command;
 
 
 
 678	if (strcmp(argv0, "endefcmd") == 0) {
 679		defcmd_in_progress = false;
 680		if (!s->count)
 681			s->usable = false;
 682		if (s->usable)
 683			/* macros are always safe because when executed each
 684			 * internal command re-enters kdb_parse() and is
 685			 * safety checked individually.
 686			 */
 687			kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
 688					   s->help, 0,
 689					   KDB_ENABLE_ALWAYS_SAFE);
 690		return 0;
 691	}
 692	if (!s->usable)
 693		return KDB_NOTIMP;
 694	s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);
 695	if (!s->command) {
 696		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
 697			   cmdstr);
 698		s->usable = false;
 699		return KDB_NOTIMP;
 700	}
 701	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
 702	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
 703	kfree(save_command);
 
 704	return 0;
 705}
 706
 707static int kdb_defcmd(int argc, const char **argv)
 708{
 709	struct defcmd_set *save_defcmd_set = defcmd_set, *s;
 
 710	if (defcmd_in_progress) {
 711		kdb_printf("kdb: nested defcmd detected, assuming missing "
 712			   "endefcmd\n");
 713		kdb_defcmd2("endefcmd", "endefcmd");
 714	}
 715	if (argc == 0) {
 716		int i;
 717		for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
 718			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
 719				   s->usage, s->help);
 720			for (i = 0; i < s->count; ++i)
 721				kdb_printf("%s", s->command[i]);
 722			kdb_printf("endefcmd\n");
 
 
 
 
 
 
 
 723		}
 724		return 0;
 725	}
 726	if (argc != 3)
 727		return KDB_ARGCOUNT;
 728	if (in_dbg_master()) {
 729		kdb_printf("Command only available during kdb_init()\n");
 730		return KDB_NOTIMP;
 731	}
 732	defcmd_set = kmalloc_array(defcmd_set_count + 1, sizeof(*defcmd_set),
 733				   GFP_KDB);
 734	if (!defcmd_set)
 735		goto fail_defcmd;
 736	memcpy(defcmd_set, save_defcmd_set,
 737	       defcmd_set_count * sizeof(*defcmd_set));
 738	s = defcmd_set + defcmd_set_count;
 739	memset(s, 0, sizeof(*s));
 740	s->usable = true;
 741	s->name = kdb_strdup(argv[1], GFP_KDB);
 742	if (!s->name)
 743		goto fail_name;
 744	s->usage = kdb_strdup(argv[2], GFP_KDB);
 745	if (!s->usage)
 746		goto fail_usage;
 747	s->help = kdb_strdup(argv[3], GFP_KDB);
 748	if (!s->help)
 749		goto fail_help;
 750	if (s->usage[0] == '"') {
 751		strcpy(s->usage, argv[2]+1);
 752		s->usage[strlen(s->usage)-1] = '\0';
 753	}
 754	if (s->help[0] == '"') {
 755		strcpy(s->help, argv[3]+1);
 756		s->help[strlen(s->help)-1] = '\0';
 757	}
 758	++defcmd_set_count;
 
 759	defcmd_in_progress = true;
 760	kfree(save_defcmd_set);
 761	return 0;
 762fail_help:
 763	kfree(s->usage);
 764fail_usage:
 765	kfree(s->name);
 766fail_name:
 767	kfree(defcmd_set);
 768fail_defcmd:
 769	kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
 770	defcmd_set = save_defcmd_set;
 771	return KDB_NOTIMP;
 772}
 773
 774/*
 775 * kdb_exec_defcmd - Execute the set of commands associated with this
 776 *	defcmd name.
 777 * Inputs:
 778 *	argc	argument count
 779 *	argv	argument vector
 780 * Returns:
 781 *	zero for success, a kdb diagnostic if error
 782 */
 783static int kdb_exec_defcmd(int argc, const char **argv)
 784{
 785	int i, ret;
 786	struct defcmd_set *s;
 
 
 
 787	if (argc != 0)
 788		return KDB_ARGCOUNT;
 789	for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
 790		if (strcmp(s->name, argv[0]) == 0)
 
 791			break;
 792	}
 793	if (i == defcmd_set_count) {
 794		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 795			   argv[0]);
 796		return KDB_NOTIMP;
 797	}
 798	for (i = 0; i < s->count; ++i) {
 799		/* Recursive use of kdb_parse, do not use argv after
 800		 * this point */
 
 
 801		argv = NULL;
 802		kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
 803		ret = kdb_parse(s->command[i]);
 804		if (ret)
 805			return ret;
 806	}
 807	return 0;
 808}
 809
 810/* Command history */
 811#define KDB_CMD_HISTORY_COUNT	32
 812#define CMD_BUFLEN		200	/* kdb_printf: max printline
 813					 * size == 256 */
 814static unsigned int cmd_head, cmd_tail;
 815static unsigned int cmdptr;
 816static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 817static char cmd_cur[CMD_BUFLEN];
 818
 819/*
 820 * The "str" argument may point to something like  | grep xyz
 821 */
 822static void parse_grep(const char *str)
 823{
 824	int	len;
 825	char	*cp = (char *)str, *cp2;
 826
 827	/* sanity check: we should have been called with the \ first */
 828	if (*cp != '|')
 829		return;
 830	cp++;
 831	while (isspace(*cp))
 832		cp++;
 833	if (!str_has_prefix(cp, "grep ")) {
 834		kdb_printf("invalid 'pipe', see grephelp\n");
 835		return;
 836	}
 837	cp += 5;
 838	while (isspace(*cp))
 839		cp++;
 840	cp2 = strchr(cp, '\n');
 841	if (cp2)
 842		*cp2 = '\0'; /* remove the trailing newline */
 843	len = strlen(cp);
 844	if (len == 0) {
 845		kdb_printf("invalid 'pipe', see grephelp\n");
 846		return;
 847	}
 848	/* now cp points to a nonzero length search string */
 849	if (*cp == '"') {
 850		/* allow it be "x y z" by removing the "'s - there must
 851		   be two of them */
 852		cp++;
 853		cp2 = strchr(cp, '"');
 854		if (!cp2) {
 855			kdb_printf("invalid quoted string, see grephelp\n");
 856			return;
 857		}
 858		*cp2 = '\0'; /* end the string where the 2nd " was */
 859	}
 860	kdb_grep_leading = 0;
 861	if (*cp == '^') {
 862		kdb_grep_leading = 1;
 863		cp++;
 864	}
 865	len = strlen(cp);
 866	kdb_grep_trailing = 0;
 867	if (*(cp+len-1) == '$') {
 868		kdb_grep_trailing = 1;
 869		*(cp+len-1) = '\0';
 870	}
 871	len = strlen(cp);
 872	if (!len)
 873		return;
 874	if (len >= KDB_GREP_STRLEN) {
 875		kdb_printf("search string too long\n");
 876		return;
 877	}
 878	strcpy(kdb_grep_string, cp);
 879	kdb_grepping_flag++;
 880	return;
 881}
 882
 883/*
 884 * kdb_parse - Parse the command line, search the command table for a
 885 *	matching command and invoke the command function.  This
 886 *	function may be called recursively, if it is, the second call
 887 *	will overwrite argv and cbuf.  It is the caller's
 888 *	responsibility to save their argv if they recursively call
 889 *	kdb_parse().
 890 * Parameters:
 891 *      cmdstr	The input command line to be parsed.
 892 *	regs	The registers at the time kdb was entered.
 893 * Returns:
 894 *	Zero for success, a kdb diagnostic if failure.
 895 * Remarks:
 896 *	Limited to 20 tokens.
 897 *
 898 *	Real rudimentary tokenization. Basically only whitespace
 899 *	is considered a token delimeter (but special consideration
 900 *	is taken of the '=' sign as used by the 'set' command).
 901 *
 902 *	The algorithm used to tokenize the input string relies on
 903 *	there being at least one whitespace (or otherwise useless)
 904 *	character between tokens as the character immediately following
 905 *	the token is altered in-place to a null-byte to terminate the
 906 *	token string.
 907 */
 908
 909#define MAXARGC	20
 910
 911int kdb_parse(const char *cmdstr)
 912{
 913	static char *argv[MAXARGC];
 914	static int argc;
 915	static char cbuf[CMD_BUFLEN+2];
 916	char *cp;
 917	char *cpp, quoted;
 918	kdbtab_t *tp;
 919	int i, escaped, ignore_errors = 0, check_grep = 0;
 920
 921	/*
 922	 * First tokenize the command string.
 923	 */
 924	cp = (char *)cmdstr;
 925
 926	if (KDB_FLAG(CMD_INTERRUPT)) {
 927		/* Previous command was interrupted, newline must not
 928		 * repeat the command */
 929		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 930		KDB_STATE_SET(PAGER);
 931		argc = 0;	/* no repeat */
 932	}
 933
 934	if (*cp != '\n' && *cp != '\0') {
 935		argc = 0;
 936		cpp = cbuf;
 937		while (*cp) {
 938			/* skip whitespace */
 939			while (isspace(*cp))
 940				cp++;
 941			if ((*cp == '\0') || (*cp == '\n') ||
 942			    (*cp == '#' && !defcmd_in_progress))
 943				break;
 944			/* special case: check for | grep pattern */
 945			if (*cp == '|') {
 946				check_grep++;
 947				break;
 948			}
 949			if (cpp >= cbuf + CMD_BUFLEN) {
 950				kdb_printf("kdb_parse: command buffer "
 951					   "overflow, command ignored\n%s\n",
 952					   cmdstr);
 953				return KDB_NOTFOUND;
 954			}
 955			if (argc >= MAXARGC - 1) {
 956				kdb_printf("kdb_parse: too many arguments, "
 957					   "command ignored\n%s\n", cmdstr);
 958				return KDB_NOTFOUND;
 959			}
 960			argv[argc++] = cpp;
 961			escaped = 0;
 962			quoted = '\0';
 963			/* Copy to next unquoted and unescaped
 964			 * whitespace or '=' */
 965			while (*cp && *cp != '\n' &&
 966			       (escaped || quoted || !isspace(*cp))) {
 967				if (cpp >= cbuf + CMD_BUFLEN)
 968					break;
 969				if (escaped) {
 970					escaped = 0;
 971					*cpp++ = *cp++;
 972					continue;
 973				}
 974				if (*cp == '\\') {
 975					escaped = 1;
 976					++cp;
 977					continue;
 978				}
 979				if (*cp == quoted)
 980					quoted = '\0';
 981				else if (*cp == '\'' || *cp == '"')
 982					quoted = *cp;
 983				*cpp = *cp++;
 984				if (*cpp == '=' && !quoted)
 985					break;
 986				++cpp;
 987			}
 988			*cpp++ = '\0';	/* Squash a ws or '=' character */
 989		}
 990	}
 991	if (!argc)
 992		return 0;
 993	if (check_grep)
 994		parse_grep(cp);
 995	if (defcmd_in_progress) {
 996		int result = kdb_defcmd2(cmdstr, argv[0]);
 997		if (!defcmd_in_progress) {
 998			argc = 0;	/* avoid repeat on endefcmd */
 999			*(argv[0]) = '\0';
1000		}
1001		return result;
1002	}
1003	if (argv[0][0] == '-' && argv[0][1] &&
1004	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1005		ignore_errors = 1;
1006		++argv[0];
1007	}
1008
1009	for_each_kdbcmd(tp, i) {
1010		if (tp->cmd_name) {
1011			/*
1012			 * If this command is allowed to be abbreviated,
1013			 * check to see if this is it.
1014			 */
 
 
1015
1016			if (tp->cmd_minlen
1017			 && (strlen(argv[0]) <= tp->cmd_minlen)) {
1018				if (strncmp(argv[0],
1019					    tp->cmd_name,
1020					    tp->cmd_minlen) == 0) {
1021					break;
1022				}
1023			}
1024
1025			if (strcmp(argv[0], tp->cmd_name) == 0)
1026				break;
1027		}
1028	}
1029
1030	/*
1031	 * If we don't find a command by this name, see if the first
1032	 * few characters of this match any of the known commands.
1033	 * e.g., md1c20 should match md.
1034	 */
1035	if (i == kdb_max_commands) {
1036		for_each_kdbcmd(tp, i) {
1037			if (tp->cmd_name) {
1038				if (strncmp(argv[0],
1039					    tp->cmd_name,
1040					    strlen(tp->cmd_name)) == 0) {
1041					break;
1042				}
1043			}
1044		}
1045	}
1046
1047	if (i < kdb_max_commands) {
1048		int result;
1049
1050		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1051			return KDB_NOPERM;
1052
1053		KDB_STATE_SET(CMD);
1054		result = (*tp->cmd_func)(argc-1, (const char **)argv);
1055		if (result && ignore_errors && result > KDB_CMD_GO)
1056			result = 0;
1057		KDB_STATE_CLEAR(CMD);
1058
1059		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1060			return result;
1061
1062		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1063		if (argv[argc])
1064			*(argv[argc]) = '\0';
1065		return result;
1066	}
1067
1068	/*
1069	 * If the input with which we were presented does not
1070	 * map to an existing command, attempt to parse it as an
1071	 * address argument and display the result.   Useful for
1072	 * obtaining the address of a variable, or the nearest symbol
1073	 * to an address contained in a register.
1074	 */
1075	{
1076		unsigned long value;
1077		char *name = NULL;
1078		long offset;
1079		int nextarg = 0;
1080
1081		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1082				  &value, &offset, &name)) {
1083			return KDB_NOTFOUND;
1084		}
1085
1086		kdb_printf("%s = ", argv[0]);
1087		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1088		kdb_printf("\n");
1089		return 0;
1090	}
1091}
1092
1093
1094static int handle_ctrl_cmd(char *cmd)
1095{
1096#define CTRL_P	16
1097#define CTRL_N	14
1098
1099	/* initial situation */
1100	if (cmd_head == cmd_tail)
1101		return 0;
1102	switch (*cmd) {
1103	case CTRL_P:
1104		if (cmdptr != cmd_tail)
1105			cmdptr = (cmdptr-1) % KDB_CMD_HISTORY_COUNT;
1106		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
 
1107		return 1;
1108	case CTRL_N:
1109		if (cmdptr != cmd_head)
1110			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1111		strncpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1112		return 1;
1113	}
1114	return 0;
1115}
1116
1117/*
1118 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1119 *	the system immediately, or loop for ever on failure.
1120 */
1121static int kdb_reboot(int argc, const char **argv)
1122{
1123	emergency_restart();
1124	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1125	while (1)
1126		cpu_relax();
1127	/* NOTREACHED */
1128	return 0;
1129}
1130
1131static void kdb_dumpregs(struct pt_regs *regs)
1132{
1133	int old_lvl = console_loglevel;
1134	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1135	kdb_trap_printk++;
1136	show_regs(regs);
1137	kdb_trap_printk--;
1138	kdb_printf("\n");
1139	console_loglevel = old_lvl;
1140}
1141
1142void kdb_set_current_task(struct task_struct *p)
1143{
1144	kdb_current_task = p;
1145
1146	if (kdb_task_has_cpu(p)) {
1147		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1148		return;
1149	}
1150	kdb_current_regs = NULL;
1151}
1152
1153static void drop_newline(char *buf)
1154{
1155	size_t len = strlen(buf);
1156
1157	if (len == 0)
1158		return;
1159	if (*(buf + len - 1) == '\n')
1160		*(buf + len - 1) = '\0';
1161}
1162
1163/*
1164 * kdb_local - The main code for kdb.  This routine is invoked on a
1165 *	specific processor, it is not global.  The main kdb() routine
1166 *	ensures that only one processor at a time is in this routine.
1167 *	This code is called with the real reason code on the first
1168 *	entry to a kdb session, thereafter it is called with reason
1169 *	SWITCH, even if the user goes back to the original cpu.
1170 * Inputs:
1171 *	reason		The reason KDB was invoked
1172 *	error		The hardware-defined error code
1173 *	regs		The exception frame at time of fault/breakpoint.
1174 *	db_result	Result code from the break or debug point.
1175 * Returns:
1176 *	0	KDB was invoked for an event which it wasn't responsible
1177 *	1	KDB handled the event for which it was invoked.
1178 *	KDB_CMD_GO	User typed 'go'.
1179 *	KDB_CMD_CPU	User switched to another cpu.
1180 *	KDB_CMD_SS	Single step.
1181 */
1182static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1183		     kdb_dbtrap_t db_result)
1184{
1185	char *cmdbuf;
1186	int diag;
1187	struct task_struct *kdb_current =
1188		kdb_curr_task(raw_smp_processor_id());
1189
1190	KDB_DEBUG_STATE("kdb_local 1", reason);
 
 
 
1191	kdb_go_count = 0;
1192	if (reason == KDB_REASON_DEBUG) {
1193		/* special case below */
1194	} else {
1195		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1196			   kdb_current, kdb_current ? kdb_current->pid : 0);
1197#if defined(CONFIG_SMP)
1198		kdb_printf("on processor %d ", raw_smp_processor_id());
1199#endif
1200	}
1201
1202	switch (reason) {
1203	case KDB_REASON_DEBUG:
1204	{
1205		/*
1206		 * If re-entering kdb after a single step
1207		 * command, don't print the message.
1208		 */
1209		switch (db_result) {
1210		case KDB_DB_BPT:
1211			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1212				   kdb_current, kdb_current->pid);
1213#if defined(CONFIG_SMP)
1214			kdb_printf("on processor %d ", raw_smp_processor_id());
1215#endif
1216			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1217				   instruction_pointer(regs));
1218			break;
1219		case KDB_DB_SS:
1220			break;
1221		case KDB_DB_SSBPT:
1222			KDB_DEBUG_STATE("kdb_local 4", reason);
1223			return 1;	/* kdba_db_trap did the work */
1224		default:
1225			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1226				   db_result);
1227			break;
1228		}
1229
1230	}
1231		break;
1232	case KDB_REASON_ENTER:
1233		if (KDB_STATE(KEYBOARD))
1234			kdb_printf("due to Keyboard Entry\n");
1235		else
1236			kdb_printf("due to KDB_ENTER()\n");
1237		break;
1238	case KDB_REASON_KEYBOARD:
1239		KDB_STATE_SET(KEYBOARD);
1240		kdb_printf("due to Keyboard Entry\n");
1241		break;
1242	case KDB_REASON_ENTER_SLAVE:
1243		/* drop through, slaves only get released via cpu switch */
1244	case KDB_REASON_SWITCH:
1245		kdb_printf("due to cpu switch\n");
1246		break;
1247	case KDB_REASON_OOPS:
1248		kdb_printf("Oops: %s\n", kdb_diemsg);
1249		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1250			   instruction_pointer(regs));
1251		kdb_dumpregs(regs);
1252		break;
1253	case KDB_REASON_SYSTEM_NMI:
1254		kdb_printf("due to System NonMaskable Interrupt\n");
1255		break;
1256	case KDB_REASON_NMI:
1257		kdb_printf("due to NonMaskable Interrupt @ "
1258			   kdb_machreg_fmt "\n",
1259			   instruction_pointer(regs));
1260		break;
1261	case KDB_REASON_SSTEP:
1262	case KDB_REASON_BREAK:
1263		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1264			   reason == KDB_REASON_BREAK ?
1265			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1266		/*
1267		 * Determine if this breakpoint is one that we
1268		 * are interested in.
1269		 */
1270		if (db_result != KDB_DB_BPT) {
1271			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1272				   db_result);
1273			KDB_DEBUG_STATE("kdb_local 6", reason);
1274			return 0;	/* Not for us, dismiss it */
1275		}
1276		break;
1277	case KDB_REASON_RECURSE:
1278		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1279			   instruction_pointer(regs));
1280		break;
1281	default:
1282		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1283		KDB_DEBUG_STATE("kdb_local 8", reason);
1284		return 0;	/* Not for us, dismiss it */
1285	}
1286
1287	while (1) {
1288		/*
1289		 * Initialize pager context.
1290		 */
1291		kdb_nextline = 1;
1292		KDB_STATE_CLEAR(SUPPRESS);
1293		kdb_grepping_flag = 0;
1294		/* ensure the old search does not leak into '/' commands */
1295		kdb_grep_string[0] = '\0';
1296
1297		cmdbuf = cmd_cur;
1298		*cmdbuf = '\0';
1299		*(cmd_hist[cmd_head]) = '\0';
1300
1301do_full_getstr:
1302#if defined(CONFIG_SMP)
1303		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1304			 raw_smp_processor_id());
1305#else
1306		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"));
1307#endif
1308		if (defcmd_in_progress)
1309			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1310
1311		/*
1312		 * Fetch command from keyboard
1313		 */
1314		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1315		if (*cmdbuf != '\n') {
1316			if (*cmdbuf < 32) {
1317				if (cmdptr == cmd_head) {
1318					strncpy(cmd_hist[cmd_head], cmd_cur,
1319						CMD_BUFLEN);
1320					*(cmd_hist[cmd_head] +
1321					  strlen(cmd_hist[cmd_head])-1) = '\0';
1322				}
1323				if (!handle_ctrl_cmd(cmdbuf))
1324					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1325				cmdbuf = cmd_cur;
1326				goto do_full_getstr;
1327			} else {
1328				strncpy(cmd_hist[cmd_head], cmd_cur,
1329					CMD_BUFLEN);
1330			}
1331
1332			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1333			if (cmd_head == cmd_tail)
1334				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1335		}
1336
1337		cmdptr = cmd_head;
1338		diag = kdb_parse(cmdbuf);
1339		if (diag == KDB_NOTFOUND) {
1340			drop_newline(cmdbuf);
1341			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1342			diag = 0;
1343		}
1344		if (diag == KDB_CMD_GO
1345		 || diag == KDB_CMD_CPU
1346		 || diag == KDB_CMD_SS
1347		 || diag == KDB_CMD_KGDB)
1348			break;
1349
1350		if (diag)
1351			kdb_cmderror(diag);
1352	}
1353	KDB_DEBUG_STATE("kdb_local 9", diag);
1354	return diag;
1355}
1356
1357
1358/*
1359 * kdb_print_state - Print the state data for the current processor
1360 *	for debugging.
1361 * Inputs:
1362 *	text		Identifies the debug point
1363 *	value		Any integer value to be printed, e.g. reason code.
1364 */
1365void kdb_print_state(const char *text, int value)
1366{
1367	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1368		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1369		   kdb_state);
1370}
1371
1372/*
1373 * kdb_main_loop - After initial setup and assignment of the
1374 *	controlling cpu, all cpus are in this loop.  One cpu is in
1375 *	control and will issue the kdb prompt, the others will spin
1376 *	until 'go' or cpu switch.
1377 *
1378 *	To get a consistent view of the kernel stacks for all
1379 *	processes, this routine is invoked from the main kdb code via
1380 *	an architecture specific routine.  kdba_main_loop is
1381 *	responsible for making the kernel stacks consistent for all
1382 *	processes, there should be no difference between a blocked
1383 *	process and a running process as far as kdb is concerned.
1384 * Inputs:
1385 *	reason		The reason KDB was invoked
1386 *	error		The hardware-defined error code
1387 *	reason2		kdb's current reason code.
1388 *			Initially error but can change
1389 *			according to kdb state.
1390 *	db_result	Result code from break or debug point.
1391 *	regs		The exception frame at time of fault/breakpoint.
1392 *			should always be valid.
1393 * Returns:
1394 *	0	KDB was invoked for an event which it wasn't responsible
1395 *	1	KDB handled the event for which it was invoked.
1396 */
1397int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1398	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1399{
1400	int result = 1;
1401	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1402	while (1) {
1403		/*
1404		 * All processors except the one that is in control
1405		 * will spin here.
1406		 */
1407		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1408		while (KDB_STATE(HOLD_CPU)) {
1409			/* state KDB is turned off by kdb_cpu to see if the
1410			 * other cpus are still live, each cpu in this loop
1411			 * turns it back on.
1412			 */
1413			if (!KDB_STATE(KDB))
1414				KDB_STATE_SET(KDB);
1415		}
1416
1417		KDB_STATE_CLEAR(SUPPRESS);
1418		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1419		if (KDB_STATE(LEAVING))
1420			break;	/* Another cpu said 'go' */
1421		/* Still using kdb, this processor is in control */
1422		result = kdb_local(reason2, error, regs, db_result);
1423		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1424
1425		if (result == KDB_CMD_CPU)
1426			break;
1427
1428		if (result == KDB_CMD_SS) {
1429			KDB_STATE_SET(DOING_SS);
1430			break;
1431		}
1432
1433		if (result == KDB_CMD_KGDB) {
1434			if (!KDB_STATE(DOING_KGDB))
1435				kdb_printf("Entering please attach debugger "
1436					   "or use $D#44+ or $3#33\n");
1437			break;
1438		}
1439		if (result && result != 1 && result != KDB_CMD_GO)
1440			kdb_printf("\nUnexpected kdb_local return code %d\n",
1441				   result);
1442		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1443		break;
1444	}
1445	if (KDB_STATE(DOING_SS))
1446		KDB_STATE_CLEAR(SSBPT);
1447
1448	/* Clean up any keyboard devices before leaving */
1449	kdb_kbd_cleanup_state();
1450
1451	return result;
1452}
1453
1454/*
1455 * kdb_mdr - This function implements the guts of the 'mdr', memory
1456 * read command.
1457 *	mdr  <addr arg>,<byte count>
1458 * Inputs:
1459 *	addr	Start address
1460 *	count	Number of bytes
1461 * Returns:
1462 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1463 */
1464static int kdb_mdr(unsigned long addr, unsigned int count)
1465{
1466	unsigned char c;
1467	while (count--) {
1468		if (kdb_getarea(c, addr))
1469			return 0;
1470		kdb_printf("%02x", c);
1471		addr++;
1472	}
1473	kdb_printf("\n");
1474	return 0;
1475}
1476
1477/*
1478 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1479 *	'md8' 'mdr' and 'mds' commands.
1480 *
1481 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1482 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1483 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1484 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1485 *	mdr  <addr arg>,<byte count>
1486 */
1487static void kdb_md_line(const char *fmtstr, unsigned long addr,
1488			int symbolic, int nosect, int bytesperword,
1489			int num, int repeat, int phys)
1490{
1491	/* print just one line of data */
1492	kdb_symtab_t symtab;
1493	char cbuf[32];
1494	char *c = cbuf;
1495	int i;
1496	int j;
1497	unsigned long word;
1498
1499	memset(cbuf, '\0', sizeof(cbuf));
1500	if (phys)
1501		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1502	else
1503		kdb_printf(kdb_machreg_fmt0 " ", addr);
1504
1505	for (i = 0; i < num && repeat--; i++) {
1506		if (phys) {
1507			if (kdb_getphysword(&word, addr, bytesperword))
1508				break;
1509		} else if (kdb_getword(&word, addr, bytesperword))
1510			break;
1511		kdb_printf(fmtstr, word);
1512		if (symbolic)
1513			kdbnearsym(word, &symtab);
1514		else
1515			memset(&symtab, 0, sizeof(symtab));
1516		if (symtab.sym_name) {
1517			kdb_symbol_print(word, &symtab, 0);
1518			if (!nosect) {
1519				kdb_printf("\n");
1520				kdb_printf("                       %s %s "
1521					   kdb_machreg_fmt " "
1522					   kdb_machreg_fmt " "
1523					   kdb_machreg_fmt, symtab.mod_name,
1524					   symtab.sec_name, symtab.sec_start,
1525					   symtab.sym_start, symtab.sym_end);
1526			}
1527			addr += bytesperword;
1528		} else {
1529			union {
1530				u64 word;
1531				unsigned char c[8];
1532			} wc;
1533			unsigned char *cp;
1534#ifdef	__BIG_ENDIAN
1535			cp = wc.c + 8 - bytesperword;
1536#else
1537			cp = wc.c;
1538#endif
1539			wc.word = word;
1540#define printable_char(c) \
1541	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1542			for (j = 0; j < bytesperword; j++)
1543				*c++ = printable_char(*cp++);
1544			addr += bytesperword;
1545#undef printable_char
1546		}
1547	}
1548	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1549		   " ", cbuf);
1550}
1551
1552static int kdb_md(int argc, const char **argv)
1553{
1554	static unsigned long last_addr;
1555	static int last_radix, last_bytesperword, last_repeat;
1556	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1557	int nosect = 0;
1558	char fmtchar, fmtstr[64];
1559	unsigned long addr;
1560	unsigned long word;
1561	long offset = 0;
1562	int symbolic = 0;
1563	int valid = 0;
1564	int phys = 0;
1565	int raw = 0;
1566
1567	kdbgetintenv("MDCOUNT", &mdcount);
1568	kdbgetintenv("RADIX", &radix);
1569	kdbgetintenv("BYTESPERWORD", &bytesperword);
1570
1571	/* Assume 'md <addr>' and start with environment values */
1572	repeat = mdcount * 16 / bytesperword;
1573
1574	if (strcmp(argv[0], "mdr") == 0) {
1575		if (argc == 2 || (argc == 0 && last_addr != 0))
1576			valid = raw = 1;
1577		else
1578			return KDB_ARGCOUNT;
1579	} else if (isdigit(argv[0][2])) {
1580		bytesperword = (int)(argv[0][2] - '0');
1581		if (bytesperword == 0) {
1582			bytesperword = last_bytesperword;
1583			if (bytesperword == 0)
1584				bytesperword = 4;
1585		}
1586		last_bytesperword = bytesperword;
1587		repeat = mdcount * 16 / bytesperword;
1588		if (!argv[0][3])
1589			valid = 1;
1590		else if (argv[0][3] == 'c' && argv[0][4]) {
1591			char *p;
1592			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1593			mdcount = ((repeat * bytesperword) + 15) / 16;
1594			valid = !*p;
1595		}
1596		last_repeat = repeat;
1597	} else if (strcmp(argv[0], "md") == 0)
1598		valid = 1;
1599	else if (strcmp(argv[0], "mds") == 0)
1600		valid = 1;
1601	else if (strcmp(argv[0], "mdp") == 0) {
1602		phys = valid = 1;
1603	}
1604	if (!valid)
1605		return KDB_NOTFOUND;
1606
1607	if (argc == 0) {
1608		if (last_addr == 0)
1609			return KDB_ARGCOUNT;
1610		addr = last_addr;
1611		radix = last_radix;
1612		bytesperword = last_bytesperword;
1613		repeat = last_repeat;
1614		if (raw)
1615			mdcount = repeat;
1616		else
1617			mdcount = ((repeat * bytesperword) + 15) / 16;
1618	}
1619
1620	if (argc) {
1621		unsigned long val;
1622		int diag, nextarg = 1;
1623		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1624				     &offset, NULL);
1625		if (diag)
1626			return diag;
1627		if (argc > nextarg+2)
1628			return KDB_ARGCOUNT;
1629
1630		if (argc >= nextarg) {
1631			diag = kdbgetularg(argv[nextarg], &val);
1632			if (!diag) {
1633				mdcount = (int) val;
1634				if (raw)
1635					repeat = mdcount;
1636				else
1637					repeat = mdcount * 16 / bytesperword;
1638			}
1639		}
1640		if (argc >= nextarg+1) {
1641			diag = kdbgetularg(argv[nextarg+1], &val);
1642			if (!diag)
1643				radix = (int) val;
1644		}
1645	}
1646
1647	if (strcmp(argv[0], "mdr") == 0) {
1648		int ret;
1649		last_addr = addr;
1650		ret = kdb_mdr(addr, mdcount);
1651		last_addr += mdcount;
1652		last_repeat = mdcount;
1653		last_bytesperword = bytesperword; // to make REPEAT happy
1654		return ret;
1655	}
1656
1657	switch (radix) {
1658	case 10:
1659		fmtchar = 'd';
1660		break;
1661	case 16:
1662		fmtchar = 'x';
1663		break;
1664	case 8:
1665		fmtchar = 'o';
1666		break;
1667	default:
1668		return KDB_BADRADIX;
1669	}
1670
1671	last_radix = radix;
1672
1673	if (bytesperword > KDB_WORD_SIZE)
1674		return KDB_BADWIDTH;
1675
1676	switch (bytesperword) {
1677	case 8:
1678		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1679		break;
1680	case 4:
1681		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1682		break;
1683	case 2:
1684		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1685		break;
1686	case 1:
1687		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1688		break;
1689	default:
1690		return KDB_BADWIDTH;
1691	}
1692
1693	last_repeat = repeat;
1694	last_bytesperword = bytesperword;
1695
1696	if (strcmp(argv[0], "mds") == 0) {
1697		symbolic = 1;
1698		/* Do not save these changes as last_*, they are temporary mds
1699		 * overrides.
1700		 */
1701		bytesperword = KDB_WORD_SIZE;
1702		repeat = mdcount;
1703		kdbgetintenv("NOSECT", &nosect);
1704	}
1705
1706	/* Round address down modulo BYTESPERWORD */
1707
1708	addr &= ~(bytesperword-1);
1709
1710	while (repeat > 0) {
1711		unsigned long a;
1712		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1713
1714		if (KDB_FLAG(CMD_INTERRUPT))
1715			return 0;
1716		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1717			if (phys) {
1718				if (kdb_getphysword(&word, a, bytesperword)
1719						|| word)
1720					break;
1721			} else if (kdb_getword(&word, a, bytesperword) || word)
1722				break;
1723		}
1724		n = min(num, repeat);
1725		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1726			    num, repeat, phys);
1727		addr += bytesperword * n;
1728		repeat -= n;
1729		z = (z + num - 1) / num;
1730		if (z > 2) {
1731			int s = num * (z-2);
1732			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1733				   " zero suppressed\n",
1734				addr, addr + bytesperword * s - 1);
1735			addr += bytesperword * s;
1736			repeat -= s;
1737		}
1738	}
1739	last_addr = addr;
1740
1741	return 0;
1742}
1743
1744/*
1745 * kdb_mm - This function implements the 'mm' command.
1746 *	mm address-expression new-value
1747 * Remarks:
1748 *	mm works on machine words, mmW works on bytes.
1749 */
1750static int kdb_mm(int argc, const char **argv)
1751{
1752	int diag;
1753	unsigned long addr;
1754	long offset = 0;
1755	unsigned long contents;
1756	int nextarg;
1757	int width;
1758
1759	if (argv[0][2] && !isdigit(argv[0][2]))
1760		return KDB_NOTFOUND;
1761
1762	if (argc < 2)
1763		return KDB_ARGCOUNT;
1764
1765	nextarg = 1;
1766	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1767	if (diag)
1768		return diag;
1769
1770	if (nextarg > argc)
1771		return KDB_ARGCOUNT;
1772	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1773	if (diag)
1774		return diag;
1775
1776	if (nextarg != argc + 1)
1777		return KDB_ARGCOUNT;
1778
1779	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1780	diag = kdb_putword(addr, contents, width);
1781	if (diag)
1782		return diag;
1783
1784	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1785
1786	return 0;
1787}
1788
1789/*
1790 * kdb_go - This function implements the 'go' command.
1791 *	go [address-expression]
1792 */
1793static int kdb_go(int argc, const char **argv)
1794{
1795	unsigned long addr;
1796	int diag;
1797	int nextarg;
1798	long offset;
1799
1800	if (raw_smp_processor_id() != kdb_initial_cpu) {
1801		kdb_printf("go must execute on the entry cpu, "
1802			   "please use \"cpu %d\" and then execute go\n",
1803			   kdb_initial_cpu);
1804		return KDB_BADCPUNUM;
1805	}
1806	if (argc == 1) {
1807		nextarg = 1;
1808		diag = kdbgetaddrarg(argc, argv, &nextarg,
1809				     &addr, &offset, NULL);
1810		if (diag)
1811			return diag;
1812	} else if (argc) {
1813		return KDB_ARGCOUNT;
1814	}
1815
1816	diag = KDB_CMD_GO;
1817	if (KDB_FLAG(CATASTROPHIC)) {
1818		kdb_printf("Catastrophic error detected\n");
1819		kdb_printf("kdb_continue_catastrophic=%d, ",
1820			kdb_continue_catastrophic);
1821		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1822			kdb_printf("type go a second time if you really want "
1823				   "to continue\n");
1824			return 0;
1825		}
1826		if (kdb_continue_catastrophic == 2) {
1827			kdb_printf("forcing reboot\n");
1828			kdb_reboot(0, NULL);
1829		}
1830		kdb_printf("attempting to continue\n");
1831	}
1832	return diag;
1833}
1834
1835/*
1836 * kdb_rd - This function implements the 'rd' command.
1837 */
1838static int kdb_rd(int argc, const char **argv)
1839{
1840	int len = kdb_check_regs();
1841#if DBG_MAX_REG_NUM > 0
1842	int i;
1843	char *rname;
1844	int rsize;
1845	u64 reg64;
1846	u32 reg32;
1847	u16 reg16;
1848	u8 reg8;
1849
1850	if (len)
1851		return len;
1852
1853	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1854		rsize = dbg_reg_def[i].size * 2;
1855		if (rsize > 16)
1856			rsize = 2;
1857		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1858			len = 0;
1859			kdb_printf("\n");
1860		}
1861		if (len)
1862			len += kdb_printf("  ");
1863		switch(dbg_reg_def[i].size * 8) {
1864		case 8:
1865			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1866			if (!rname)
1867				break;
1868			len += kdb_printf("%s: %02x", rname, reg8);
1869			break;
1870		case 16:
1871			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1872			if (!rname)
1873				break;
1874			len += kdb_printf("%s: %04x", rname, reg16);
1875			break;
1876		case 32:
1877			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1878			if (!rname)
1879				break;
1880			len += kdb_printf("%s: %08x", rname, reg32);
1881			break;
1882		case 64:
1883			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1884			if (!rname)
1885				break;
1886			len += kdb_printf("%s: %016llx", rname, reg64);
1887			break;
1888		default:
1889			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1890		}
1891	}
1892	kdb_printf("\n");
1893#else
1894	if (len)
1895		return len;
1896
1897	kdb_dumpregs(kdb_current_regs);
1898#endif
1899	return 0;
1900}
1901
1902/*
1903 * kdb_rm - This function implements the 'rm' (register modify)  command.
1904 *	rm register-name new-contents
1905 * Remarks:
1906 *	Allows register modification with the same restrictions as gdb
1907 */
1908static int kdb_rm(int argc, const char **argv)
1909{
1910#if DBG_MAX_REG_NUM > 0
1911	int diag;
1912	const char *rname;
1913	int i;
1914	u64 reg64;
1915	u32 reg32;
1916	u16 reg16;
1917	u8 reg8;
1918
1919	if (argc != 2)
1920		return KDB_ARGCOUNT;
1921	/*
1922	 * Allow presence or absence of leading '%' symbol.
1923	 */
1924	rname = argv[1];
1925	if (*rname == '%')
1926		rname++;
1927
1928	diag = kdbgetu64arg(argv[2], &reg64);
1929	if (diag)
1930		return diag;
1931
1932	diag = kdb_check_regs();
1933	if (diag)
1934		return diag;
1935
1936	diag = KDB_BADREG;
1937	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1938		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1939			diag = 0;
1940			break;
1941		}
1942	}
1943	if (!diag) {
1944		switch(dbg_reg_def[i].size * 8) {
1945		case 8:
1946			reg8 = reg64;
1947			dbg_set_reg(i, &reg8, kdb_current_regs);
1948			break;
1949		case 16:
1950			reg16 = reg64;
1951			dbg_set_reg(i, &reg16, kdb_current_regs);
1952			break;
1953		case 32:
1954			reg32 = reg64;
1955			dbg_set_reg(i, &reg32, kdb_current_regs);
1956			break;
1957		case 64:
1958			dbg_set_reg(i, &reg64, kdb_current_regs);
1959			break;
1960		}
1961	}
1962	return diag;
1963#else
1964	kdb_printf("ERROR: Register set currently not implemented\n");
1965    return 0;
1966#endif
1967}
1968
1969#if defined(CONFIG_MAGIC_SYSRQ)
1970/*
1971 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1972 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1973 *		sr <magic-sysrq-code>
1974 */
1975static int kdb_sr(int argc, const char **argv)
1976{
1977	bool check_mask =
1978	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1979
1980	if (argc != 1)
1981		return KDB_ARGCOUNT;
1982
1983	kdb_trap_printk++;
1984	__handle_sysrq(*argv[1], check_mask);
1985	kdb_trap_printk--;
1986
1987	return 0;
1988}
1989#endif	/* CONFIG_MAGIC_SYSRQ */
1990
1991/*
1992 * kdb_ef - This function implements the 'regs' (display exception
1993 *	frame) command.  This command takes an address and expects to
1994 *	find an exception frame at that address, formats and prints
1995 *	it.
1996 *		regs address-expression
1997 * Remarks:
1998 *	Not done yet.
1999 */
2000static int kdb_ef(int argc, const char **argv)
2001{
2002	int diag;
2003	unsigned long addr;
2004	long offset;
2005	int nextarg;
2006
2007	if (argc != 1)
2008		return KDB_ARGCOUNT;
2009
2010	nextarg = 1;
2011	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2012	if (diag)
2013		return diag;
2014	show_regs((struct pt_regs *)addr);
2015	return 0;
2016}
2017
2018#if defined(CONFIG_MODULES)
2019/*
2020 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2021 *	currently loaded kernel modules.
2022 *	Mostly taken from userland lsmod.
2023 */
2024static int kdb_lsmod(int argc, const char **argv)
2025{
2026	struct module *mod;
2027
2028	if (argc != 0)
2029		return KDB_ARGCOUNT;
2030
2031	kdb_printf("Module                  Size  modstruct     Used by\n");
2032	list_for_each_entry(mod, kdb_modules, list) {
2033		if (mod->state == MODULE_STATE_UNFORMED)
2034			continue;
2035
2036		kdb_printf("%-20s%8u  0x%px ", mod->name,
2037			   mod->core_layout.size, (void *)mod);
2038#ifdef CONFIG_MODULE_UNLOAD
2039		kdb_printf("%4d ", module_refcount(mod));
2040#endif
2041		if (mod->state == MODULE_STATE_GOING)
2042			kdb_printf(" (Unloading)");
2043		else if (mod->state == MODULE_STATE_COMING)
2044			kdb_printf(" (Loading)");
2045		else
2046			kdb_printf(" (Live)");
2047		kdb_printf(" 0x%px", mod->core_layout.base);
2048
2049#ifdef CONFIG_MODULE_UNLOAD
2050		{
2051			struct module_use *use;
2052			kdb_printf(" [ ");
2053			list_for_each_entry(use, &mod->source_list,
2054					    source_list)
2055				kdb_printf("%s ", use->target->name);
2056			kdb_printf("]\n");
2057		}
2058#endif
2059	}
2060
2061	return 0;
2062}
2063
2064#endif	/* CONFIG_MODULES */
2065
2066/*
2067 * kdb_env - This function implements the 'env' command.  Display the
2068 *	current environment variables.
2069 */
2070
2071static int kdb_env(int argc, const char **argv)
2072{
2073	int i;
2074
2075	for (i = 0; i < __nenv; i++) {
2076		if (__env[i])
2077			kdb_printf("%s\n", __env[i]);
2078	}
2079
2080	if (KDB_DEBUG(MASK))
2081		kdb_printf("KDBFLAGS=0x%x\n", kdb_flags);
 
2082
2083	return 0;
2084}
2085
2086#ifdef CONFIG_PRINTK
2087/*
2088 * kdb_dmesg - This function implements the 'dmesg' command to display
2089 *	the contents of the syslog buffer.
2090 *		dmesg [lines] [adjust]
2091 */
2092static int kdb_dmesg(int argc, const char **argv)
2093{
2094	int diag;
2095	int logging;
2096	int lines = 0;
2097	int adjust = 0;
2098	int n = 0;
2099	int skip = 0;
2100	struct kmsg_dumper dumper = { .active = 1 };
2101	size_t len;
2102	char buf[201];
2103
2104	if (argc > 2)
2105		return KDB_ARGCOUNT;
2106	if (argc) {
2107		char *cp;
2108		lines = simple_strtol(argv[1], &cp, 0);
2109		if (*cp)
2110			lines = 0;
2111		if (argc > 1) {
2112			adjust = simple_strtoul(argv[2], &cp, 0);
2113			if (*cp || adjust < 0)
2114				adjust = 0;
2115		}
2116	}
2117
2118	/* disable LOGGING if set */
2119	diag = kdbgetintenv("LOGGING", &logging);
2120	if (!diag && logging) {
2121		const char *setargs[] = { "set", "LOGGING", "0" };
2122		kdb_set(2, setargs);
2123	}
2124
2125	kmsg_dump_rewind_nolock(&dumper);
2126	while (kmsg_dump_get_line_nolock(&dumper, 1, NULL, 0, NULL))
2127		n++;
2128
2129	if (lines < 0) {
2130		if (adjust >= n)
2131			kdb_printf("buffer only contains %d lines, nothing "
2132				   "printed\n", n);
2133		else if (adjust - lines >= n)
2134			kdb_printf("buffer only contains %d lines, last %d "
2135				   "lines printed\n", n, n - adjust);
2136		skip = adjust;
2137		lines = abs(lines);
2138	} else if (lines > 0) {
2139		skip = n - lines - adjust;
2140		lines = abs(lines);
2141		if (adjust >= n) {
2142			kdb_printf("buffer only contains %d lines, "
2143				   "nothing printed\n", n);
2144			skip = n;
2145		} else if (skip < 0) {
2146			lines += skip;
2147			skip = 0;
2148			kdb_printf("buffer only contains %d lines, first "
2149				   "%d lines printed\n", n, lines);
2150		}
2151	} else {
2152		lines = n;
2153	}
2154
2155	if (skip >= n || skip < 0)
2156		return 0;
2157
2158	kmsg_dump_rewind_nolock(&dumper);
2159	while (kmsg_dump_get_line_nolock(&dumper, 1, buf, sizeof(buf), &len)) {
2160		if (skip) {
2161			skip--;
2162			continue;
2163		}
2164		if (!lines--)
2165			break;
2166		if (KDB_FLAG(CMD_INTERRUPT))
2167			return 0;
2168
2169		kdb_printf("%.*s\n", (int)len - 1, buf);
2170	}
2171
2172	return 0;
2173}
2174#endif /* CONFIG_PRINTK */
2175
2176/* Make sure we balance enable/disable calls, must disable first. */
2177static atomic_t kdb_nmi_disabled;
2178
2179static int kdb_disable_nmi(int argc, const char *argv[])
2180{
2181	if (atomic_read(&kdb_nmi_disabled))
2182		return 0;
2183	atomic_set(&kdb_nmi_disabled, 1);
2184	arch_kgdb_ops.enable_nmi(0);
2185	return 0;
2186}
2187
2188static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2189{
2190	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2191		return -EINVAL;
2192	arch_kgdb_ops.enable_nmi(1);
2193	return 0;
2194}
2195
2196static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2197	.set = kdb_param_enable_nmi,
2198};
2199module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2200
2201/*
2202 * kdb_cpu - This function implements the 'cpu' command.
2203 *	cpu	[<cpunum>]
2204 * Returns:
2205 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2206 */
2207static void kdb_cpu_status(void)
2208{
2209	int i, start_cpu, first_print = 1;
2210	char state, prev_state = '?';
2211
2212	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2213	kdb_printf("Available cpus: ");
2214	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2215		if (!cpu_online(i)) {
2216			state = 'F';	/* cpu is offline */
2217		} else if (!kgdb_info[i].enter_kgdb) {
2218			state = 'D';	/* cpu is online but unresponsive */
2219		} else {
2220			state = ' ';	/* cpu is responding to kdb */
2221			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2222				state = 'I';	/* idle task */
2223		}
2224		if (state != prev_state) {
2225			if (prev_state != '?') {
2226				if (!first_print)
2227					kdb_printf(", ");
2228				first_print = 0;
2229				kdb_printf("%d", start_cpu);
2230				if (start_cpu < i-1)
2231					kdb_printf("-%d", i-1);
2232				if (prev_state != ' ')
2233					kdb_printf("(%c)", prev_state);
2234			}
2235			prev_state = state;
2236			start_cpu = i;
2237		}
2238	}
2239	/* print the trailing cpus, ignoring them if they are all offline */
2240	if (prev_state != 'F') {
2241		if (!first_print)
2242			kdb_printf(", ");
2243		kdb_printf("%d", start_cpu);
2244		if (start_cpu < i-1)
2245			kdb_printf("-%d", i-1);
2246		if (prev_state != ' ')
2247			kdb_printf("(%c)", prev_state);
2248	}
2249	kdb_printf("\n");
2250}
2251
2252static int kdb_cpu(int argc, const char **argv)
2253{
2254	unsigned long cpunum;
2255	int diag;
2256
2257	if (argc == 0) {
2258		kdb_cpu_status();
2259		return 0;
2260	}
2261
2262	if (argc != 1)
2263		return KDB_ARGCOUNT;
2264
2265	diag = kdbgetularg(argv[1], &cpunum);
2266	if (diag)
2267		return diag;
2268
2269	/*
2270	 * Validate cpunum
2271	 */
2272	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2273		return KDB_BADCPUNUM;
2274
2275	dbg_switch_cpu = cpunum;
2276
2277	/*
2278	 * Switch to other cpu
2279	 */
2280	return KDB_CMD_CPU;
2281}
2282
2283/* The user may not realize that ps/bta with no parameters does not print idle
2284 * or sleeping system daemon processes, so tell them how many were suppressed.
2285 */
2286void kdb_ps_suppressed(void)
2287{
2288	int idle = 0, daemon = 0;
2289	unsigned long mask_I = kdb_task_state_string("I"),
2290		      mask_M = kdb_task_state_string("M");
2291	unsigned long cpu;
2292	const struct task_struct *p, *g;
2293	for_each_online_cpu(cpu) {
2294		p = kdb_curr_task(cpu);
2295		if (kdb_task_state(p, mask_I))
2296			++idle;
2297	}
2298	kdb_do_each_thread(g, p) {
2299		if (kdb_task_state(p, mask_M))
2300			++daemon;
2301	} kdb_while_each_thread(g, p);
2302	if (idle || daemon) {
2303		if (idle)
2304			kdb_printf("%d idle process%s (state I)%s\n",
2305				   idle, idle == 1 ? "" : "es",
2306				   daemon ? " and " : "");
2307		if (daemon)
2308			kdb_printf("%d sleeping system daemon (state M) "
2309				   "process%s", daemon,
2310				   daemon == 1 ? "" : "es");
2311		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2312	}
2313}
2314
2315/*
2316 * kdb_ps - This function implements the 'ps' command which shows a
2317 *	list of the active processes.
2318 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2319 */
2320void kdb_ps1(const struct task_struct *p)
2321{
2322	int cpu;
2323	unsigned long tmp;
2324
2325	if (!p || probe_kernel_read(&tmp, (char *)p, sizeof(unsigned long)))
 
2326		return;
2327
2328	cpu = kdb_process_cpu(p);
2329	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2330		   (void *)p, p->pid, p->parent->pid,
2331		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2332		   kdb_task_state_char(p),
2333		   (void *)(&p->thread),
2334		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2335		   p->comm);
2336	if (kdb_task_has_cpu(p)) {
2337		if (!KDB_TSK(cpu)) {
2338			kdb_printf("  Error: no saved data for this cpu\n");
2339		} else {
2340			if (KDB_TSK(cpu) != p)
2341				kdb_printf("  Error: does not match running "
2342				   "process table (0x%px)\n", KDB_TSK(cpu));
2343		}
2344	}
2345}
2346
 
 
 
 
 
 
 
2347static int kdb_ps(int argc, const char **argv)
2348{
2349	struct task_struct *g, *p;
2350	unsigned long mask, cpu;
 
2351
2352	if (argc == 0)
2353		kdb_ps_suppressed();
2354	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2355		(int)(2*sizeof(void *))+2, "Task Addr",
2356		(int)(2*sizeof(void *))+2, "Thread");
2357	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2358	/* Run the active tasks first */
2359	for_each_online_cpu(cpu) {
2360		if (KDB_FLAG(CMD_INTERRUPT))
2361			return 0;
2362		p = kdb_curr_task(cpu);
2363		if (kdb_task_state(p, mask))
2364			kdb_ps1(p);
2365	}
2366	kdb_printf("\n");
2367	/* Now the real tasks */
2368	kdb_do_each_thread(g, p) {
2369		if (KDB_FLAG(CMD_INTERRUPT))
2370			return 0;
2371		if (kdb_task_state(p, mask))
2372			kdb_ps1(p);
2373	} kdb_while_each_thread(g, p);
2374
2375	return 0;
2376}
2377
2378/*
2379 * kdb_pid - This function implements the 'pid' command which switches
2380 *	the currently active process.
2381 *		pid [<pid> | R]
2382 */
2383static int kdb_pid(int argc, const char **argv)
2384{
2385	struct task_struct *p;
2386	unsigned long val;
2387	int diag;
2388
2389	if (argc > 1)
2390		return KDB_ARGCOUNT;
2391
2392	if (argc) {
2393		if (strcmp(argv[1], "R") == 0) {
2394			p = KDB_TSK(kdb_initial_cpu);
2395		} else {
2396			diag = kdbgetularg(argv[1], &val);
2397			if (diag)
2398				return KDB_BADINT;
2399
2400			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2401			if (!p) {
2402				kdb_printf("No task with pid=%d\n", (pid_t)val);
2403				return 0;
2404			}
2405		}
2406		kdb_set_current_task(p);
2407	}
2408	kdb_printf("KDB current process is %s(pid=%d)\n",
2409		   kdb_current_task->comm,
2410		   kdb_current_task->pid);
2411
2412	return 0;
2413}
2414
2415static int kdb_kgdb(int argc, const char **argv)
2416{
2417	return KDB_CMD_KGDB;
2418}
2419
2420/*
2421 * kdb_help - This function implements the 'help' and '?' commands.
2422 */
2423static int kdb_help(int argc, const char **argv)
2424{
2425	kdbtab_t *kt;
2426	int i;
2427
2428	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2429	kdb_printf("-----------------------------"
2430		   "-----------------------------\n");
2431	for_each_kdbcmd(kt, i) {
2432		char *space = "";
2433		if (KDB_FLAG(CMD_INTERRUPT))
2434			return 0;
2435		if (!kt->cmd_name)
2436			continue;
2437		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2438			continue;
2439		if (strlen(kt->cmd_usage) > 20)
2440			space = "\n                                    ";
2441		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2442			   kt->cmd_usage, space, kt->cmd_help);
2443	}
2444	return 0;
2445}
2446
2447/*
2448 * kdb_kill - This function implements the 'kill' commands.
2449 */
2450static int kdb_kill(int argc, const char **argv)
2451{
2452	long sig, pid;
2453	char *endp;
2454	struct task_struct *p;
2455
2456	if (argc != 2)
2457		return KDB_ARGCOUNT;
2458
2459	sig = simple_strtol(argv[1], &endp, 0);
2460	if (*endp)
2461		return KDB_BADINT;
2462	if ((sig >= 0) || !valid_signal(-sig)) {
2463		kdb_printf("Invalid signal parameter.<-signal>\n");
2464		return 0;
2465	}
2466	sig = -sig;
2467
2468	pid = simple_strtol(argv[2], &endp, 0);
2469	if (*endp)
2470		return KDB_BADINT;
2471	if (pid <= 0) {
2472		kdb_printf("Process ID must be large than 0.\n");
2473		return 0;
2474	}
2475
2476	/* Find the process. */
2477	p = find_task_by_pid_ns(pid, &init_pid_ns);
2478	if (!p) {
2479		kdb_printf("The specified process isn't found.\n");
2480		return 0;
2481	}
2482	p = p->group_leader;
2483	kdb_send_sig(p, sig);
2484	return 0;
2485}
2486
2487/*
2488 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2489 * I cannot call that code directly from kdb, it has an unconditional
2490 * cli()/sti() and calls routines that take locks which can stop the debugger.
2491 */
2492static void kdb_sysinfo(struct sysinfo *val)
2493{
2494	u64 uptime = ktime_get_mono_fast_ns();
2495
2496	memset(val, 0, sizeof(*val));
2497	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2498	val->loads[0] = avenrun[0];
2499	val->loads[1] = avenrun[1];
2500	val->loads[2] = avenrun[2];
2501	val->procs = nr_threads-1;
2502	si_meminfo(val);
2503
2504	return;
2505}
2506
2507/*
2508 * kdb_summary - This function implements the 'summary' command.
2509 */
2510static int kdb_summary(int argc, const char **argv)
2511{
2512	time64_t now;
2513	struct tm tm;
2514	struct sysinfo val;
2515
2516	if (argc)
2517		return KDB_ARGCOUNT;
2518
2519	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2520	kdb_printf("release    %s\n", init_uts_ns.name.release);
2521	kdb_printf("version    %s\n", init_uts_ns.name.version);
2522	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2523	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2524	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2525
2526	now = __ktime_get_real_seconds();
2527	time64_to_tm(now, 0, &tm);
2528	kdb_printf("date       %04ld-%02d-%02d %02d:%02d:%02d "
2529		   "tz_minuteswest %d\n",
2530		1900+tm.tm_year, tm.tm_mon+1, tm.tm_mday,
2531		tm.tm_hour, tm.tm_min, tm.tm_sec,
2532		sys_tz.tz_minuteswest);
2533
2534	kdb_sysinfo(&val);
2535	kdb_printf("uptime     ");
2536	if (val.uptime > (24*60*60)) {
2537		int days = val.uptime / (24*60*60);
2538		val.uptime %= (24*60*60);
2539		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2540	}
2541	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2542
2543	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2544		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2545		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2546		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2547
2548	/* Display in kilobytes */
2549#define K(x) ((x) << (PAGE_SHIFT - 10))
2550	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2551		   "Buffers:        %8lu kB\n",
2552		   K(val.totalram), K(val.freeram), K(val.bufferram));
2553	return 0;
2554}
2555
2556/*
2557 * kdb_per_cpu - This function implements the 'per_cpu' command.
2558 */
2559static int kdb_per_cpu(int argc, const char **argv)
2560{
2561	char fmtstr[64];
2562	int cpu, diag, nextarg = 1;
2563	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2564
2565	if (argc < 1 || argc > 3)
2566		return KDB_ARGCOUNT;
2567
2568	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2569	if (diag)
2570		return diag;
2571
2572	if (argc >= 2) {
2573		diag = kdbgetularg(argv[2], &bytesperword);
2574		if (diag)
2575			return diag;
2576	}
2577	if (!bytesperword)
2578		bytesperword = KDB_WORD_SIZE;
2579	else if (bytesperword > KDB_WORD_SIZE)
2580		return KDB_BADWIDTH;
2581	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2582	if (argc >= 3) {
2583		diag = kdbgetularg(argv[3], &whichcpu);
2584		if (diag)
2585			return diag;
2586		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2587			kdb_printf("cpu %ld is not online\n", whichcpu);
2588			return KDB_BADCPUNUM;
2589		}
2590	}
2591
2592	/* Most architectures use __per_cpu_offset[cpu], some use
2593	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2594	 */
2595#ifdef	__per_cpu_offset
2596#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2597#else
2598#ifdef	CONFIG_SMP
2599#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2600#else
2601#define KDB_PCU(cpu) 0
2602#endif
2603#endif
2604	for_each_online_cpu(cpu) {
2605		if (KDB_FLAG(CMD_INTERRUPT))
2606			return 0;
2607
2608		if (whichcpu != ~0UL && whichcpu != cpu)
2609			continue;
2610		addr = symaddr + KDB_PCU(cpu);
2611		diag = kdb_getword(&val, addr, bytesperword);
2612		if (diag) {
2613			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2614				   "read, diag=%d\n", cpu, addr, diag);
2615			continue;
2616		}
2617		kdb_printf("%5d ", cpu);
2618		kdb_md_line(fmtstr, addr,
2619			bytesperword == KDB_WORD_SIZE,
2620			1, bytesperword, 1, 1, 0);
2621	}
2622#undef KDB_PCU
2623	return 0;
2624}
2625
2626/*
2627 * display help for the use of cmd | grep pattern
2628 */
2629static int kdb_grep_help(int argc, const char **argv)
2630{
2631	kdb_printf("Usage of  cmd args | grep pattern:\n");
2632	kdb_printf("  Any command's output may be filtered through an ");
2633	kdb_printf("emulated 'pipe'.\n");
2634	kdb_printf("  'grep' is just a key word.\n");
2635	kdb_printf("  The pattern may include a very limited set of "
2636		   "metacharacters:\n");
2637	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2638	kdb_printf("  And if there are spaces in the pattern, you may "
2639		   "quote it:\n");
2640	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2641		   " or \"^pat tern$\"\n");
2642	return 0;
2643}
2644
2645/*
2646 * kdb_register_flags - This function is used to register a kernel
2647 * 	debugger command.
2648 * Inputs:
2649 *	cmd	Command name
2650 *	func	Function to execute the command
2651 *	usage	A simple usage string showing arguments
2652 *	help	A simple help string describing command
2653 *	repeat	Does the command auto repeat on enter?
2654 * Returns:
2655 *	zero for success, one if a duplicate command.
2656 */
2657#define kdb_command_extend 50	/* arbitrary */
2658int kdb_register_flags(char *cmd,
2659		       kdb_func_t func,
2660		       char *usage,
2661		       char *help,
2662		       short minlen,
2663		       kdb_cmdflags_t flags)
2664{
2665	int i;
2666	kdbtab_t *kp;
2667
2668	/*
2669	 *  Brute force method to determine duplicates
2670	 */
2671	for_each_kdbcmd(kp, i) {
2672		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2673			kdb_printf("Duplicate kdb command registered: "
2674				"%s, func %px help %s\n", cmd, func, help);
2675			return 1;
2676		}
2677	}
2678
2679	/*
2680	 * Insert command into first available location in table
2681	 */
2682	for_each_kdbcmd(kp, i) {
2683		if (kp->cmd_name == NULL)
2684			break;
2685	}
2686
2687	if (i >= kdb_max_commands) {
2688		kdbtab_t *new = kmalloc_array(kdb_max_commands -
2689						KDB_BASE_CMD_MAX +
2690						kdb_command_extend,
2691					      sizeof(*new),
2692					      GFP_KDB);
2693		if (!new) {
2694			kdb_printf("Could not allocate new kdb_command "
2695				   "table\n");
2696			return 1;
2697		}
2698		if (kdb_commands) {
2699			memcpy(new, kdb_commands,
2700			  (kdb_max_commands - KDB_BASE_CMD_MAX) * sizeof(*new));
2701			kfree(kdb_commands);
2702		}
2703		memset(new + kdb_max_commands - KDB_BASE_CMD_MAX, 0,
2704		       kdb_command_extend * sizeof(*new));
2705		kdb_commands = new;
2706		kp = kdb_commands + kdb_max_commands - KDB_BASE_CMD_MAX;
2707		kdb_max_commands += kdb_command_extend;
2708	}
2709
2710	kp->cmd_name   = cmd;
2711	kp->cmd_func   = func;
2712	kp->cmd_usage  = usage;
2713	kp->cmd_help   = help;
2714	kp->cmd_minlen = minlen;
2715	kp->cmd_flags  = flags;
2716
2717	return 0;
2718}
2719EXPORT_SYMBOL_GPL(kdb_register_flags);
2720
2721
2722/*
2723 * kdb_register - Compatibility register function for commands that do
2724 *	not need to specify a repeat state.  Equivalent to
2725 *	kdb_register_flags with flags set to 0.
2726 * Inputs:
2727 *	cmd	Command name
2728 *	func	Function to execute the command
2729 *	usage	A simple usage string showing arguments
2730 *	help	A simple help string describing command
2731 * Returns:
2732 *	zero for success, one if a duplicate command.
2733 */
2734int kdb_register(char *cmd,
2735	     kdb_func_t func,
2736	     char *usage,
2737	     char *help,
2738	     short minlen)
2739{
2740	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
 
 
 
2741}
2742EXPORT_SYMBOL_GPL(kdb_register);
2743
2744/*
2745 * kdb_unregister - This function is used to unregister a kernel
2746 *	debugger command.  It is generally called when a module which
2747 *	implements kdb commands is unloaded.
2748 * Inputs:
2749 *	cmd	Command name
2750 * Returns:
2751 *	zero for success, one command not registered.
2752 */
2753int kdb_unregister(char *cmd)
2754{
2755	int i;
2756	kdbtab_t *kp;
2757
2758	/*
2759	 *  find the command.
2760	 */
2761	for_each_kdbcmd(kp, i) {
2762		if (kp->cmd_name && (strcmp(kp->cmd_name, cmd) == 0)) {
2763			kp->cmd_name = NULL;
2764			return 0;
2765		}
2766	}
2767
2768	/* Couldn't find it.  */
2769	return 1;
2770}
2771EXPORT_SYMBOL_GPL(kdb_unregister);
2772
2773/* Initialize the kdb command table. */
2774static void __init kdb_inittab(void)
2775{
2776	int i;
2777	kdbtab_t *kp;
2778
2779	for_each_kdbcmd(kp, i)
2780		kp->cmd_name = NULL;
2781
2782	kdb_register_flags("md", kdb_md, "<vaddr>",
2783	  "Display Memory Contents, also mdWcN, e.g. md8c1", 1,
2784	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2785	kdb_register_flags("mdr", kdb_md, "<vaddr> <bytes>",
2786	  "Display Raw Memory", 0,
2787	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2788	kdb_register_flags("mdp", kdb_md, "<paddr> <bytes>",
2789	  "Display Physical Memory", 0,
2790	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2791	kdb_register_flags("mds", kdb_md, "<vaddr>",
2792	  "Display Memory Symbolically", 0,
2793	  KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS);
2794	kdb_register_flags("mm", kdb_mm, "<vaddr> <contents>",
2795	  "Modify Memory Contents", 0,
2796	  KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS);
2797	kdb_register_flags("go", kdb_go, "[<vaddr>]",
2798	  "Continue Execution", 1,
2799	  KDB_ENABLE_REG_WRITE | KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2800	kdb_register_flags("rd", kdb_rd, "",
2801	  "Display Registers", 0,
2802	  KDB_ENABLE_REG_READ);
2803	kdb_register_flags("rm", kdb_rm, "<reg> <contents>",
2804	  "Modify Registers", 0,
2805	  KDB_ENABLE_REG_WRITE);
2806	kdb_register_flags("ef", kdb_ef, "<vaddr>",
2807	  "Display exception frame", 0,
2808	  KDB_ENABLE_MEM_READ);
2809	kdb_register_flags("bt", kdb_bt, "[<vaddr>]",
2810	  "Stack traceback", 1,
2811	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2812	kdb_register_flags("btp", kdb_bt, "<pid>",
2813	  "Display stack for process <pid>", 0,
2814	  KDB_ENABLE_INSPECT);
2815	kdb_register_flags("bta", kdb_bt, "[D|R|S|T|C|Z|E|U|I|M|A]",
2816	  "Backtrace all processes matching state flag", 0,
2817	  KDB_ENABLE_INSPECT);
2818	kdb_register_flags("btc", kdb_bt, "",
2819	  "Backtrace current process on each cpu", 0,
2820	  KDB_ENABLE_INSPECT);
2821	kdb_register_flags("btt", kdb_bt, "<vaddr>",
2822	  "Backtrace process given its struct task address", 0,
2823	  KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS);
2824	kdb_register_flags("env", kdb_env, "",
2825	  "Show environment variables", 0,
2826	  KDB_ENABLE_ALWAYS_SAFE);
2827	kdb_register_flags("set", kdb_set, "",
2828	  "Set environment variables", 0,
2829	  KDB_ENABLE_ALWAYS_SAFE);
2830	kdb_register_flags("help", kdb_help, "",
2831	  "Display Help Message", 1,
2832	  KDB_ENABLE_ALWAYS_SAFE);
2833	kdb_register_flags("?", kdb_help, "",
2834	  "Display Help Message", 0,
2835	  KDB_ENABLE_ALWAYS_SAFE);
2836	kdb_register_flags("cpu", kdb_cpu, "<cpunum>",
2837	  "Switch to new cpu", 0,
2838	  KDB_ENABLE_ALWAYS_SAFE_NO_ARGS);
2839	kdb_register_flags("kgdb", kdb_kgdb, "",
2840	  "Enter kgdb mode", 0, 0);
2841	kdb_register_flags("ps", kdb_ps, "[<flags>|A]",
2842	  "Display active task list", 0,
2843	  KDB_ENABLE_INSPECT);
2844	kdb_register_flags("pid", kdb_pid, "<pidnum>",
2845	  "Switch to another task", 0,
2846	  KDB_ENABLE_INSPECT);
2847	kdb_register_flags("reboot", kdb_reboot, "",
2848	  "Reboot the machine immediately", 0,
2849	  KDB_ENABLE_REBOOT);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2850#if defined(CONFIG_MODULES)
2851	kdb_register_flags("lsmod", kdb_lsmod, "",
2852	  "List loaded kernel modules", 0,
2853	  KDB_ENABLE_INSPECT);
 
 
 
2854#endif
2855#if defined(CONFIG_MAGIC_SYSRQ)
2856	kdb_register_flags("sr", kdb_sr, "<key>",
2857	  "Magic SysRq key", 0,
2858	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
2859#endif
2860#if defined(CONFIG_PRINTK)
2861	kdb_register_flags("dmesg", kdb_dmesg, "[lines]",
2862	  "Display syslog buffer", 0,
2863	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
2864#endif
2865	if (arch_kgdb_ops.enable_nmi) {
2866		kdb_register_flags("disable_nmi", kdb_disable_nmi, "",
2867		  "Disable NMI entry to KDB", 0,
2868		  KDB_ENABLE_ALWAYS_SAFE);
2869	}
2870	kdb_register_flags("defcmd", kdb_defcmd, "name \"usage\" \"help\"",
2871	  "Define a set of commands, down to endefcmd", 0,
2872	  KDB_ENABLE_ALWAYS_SAFE);
2873	kdb_register_flags("kill", kdb_kill, "<-signal> <pid>",
2874	  "Send a signal to a process", 0,
2875	  KDB_ENABLE_SIGNAL);
2876	kdb_register_flags("summary", kdb_summary, "",
2877	  "Summarize the system", 4,
2878	  KDB_ENABLE_ALWAYS_SAFE);
2879	kdb_register_flags("per_cpu", kdb_per_cpu, "<sym> [<bytes>] [<cpu>]",
2880	  "Display per_cpu variables", 3,
2881	  KDB_ENABLE_MEM_READ);
2882	kdb_register_flags("grephelp", kdb_grep_help, "",
2883	  "Display help on | grep", 0,
2884	  KDB_ENABLE_ALWAYS_SAFE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2885}
2886
2887/* Execute any commands defined in kdb_cmds.  */
2888static void __init kdb_cmd_init(void)
2889{
2890	int i, diag;
2891	for (i = 0; kdb_cmds[i]; ++i) {
2892		diag = kdb_parse(kdb_cmds[i]);
2893		if (diag)
2894			kdb_printf("kdb command %s failed, kdb diag %d\n",
2895				kdb_cmds[i], diag);
2896	}
2897	if (defcmd_in_progress) {
2898		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2899		kdb_parse("endefcmd");
2900	}
2901}
2902
2903/* Initialize kdb_printf, breakpoint tables and kdb state */
2904void __init kdb_init(int lvl)
2905{
2906	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2907	int i;
2908
2909	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2910		return;
2911	for (i = kdb_init_lvl; i < lvl; i++) {
2912		switch (i) {
2913		case KDB_NOT_INITIALIZED:
2914			kdb_inittab();		/* Initialize Command Table */
2915			kdb_initbptab();	/* Initialize Breakpoints */
2916			break;
2917		case KDB_INIT_EARLY:
2918			kdb_cmd_init();		/* Build kdb_cmds tables */
2919			break;
2920		}
2921	}
2922	kdb_init_lvl = lvl;
2923}