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