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v5.14.15
   1/*
   2 * Kernel Debugger Architecture Independent Main Code
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1999-2004 Silicon Graphics, Inc.  All Rights Reserved.
   9 * Copyright (C) 2000 Stephane Eranian <eranian@hpl.hp.com>
  10 * Xscale (R) modifications copyright (C) 2003 Intel Corporation.
  11 * Copyright (c) 2009 Wind River Systems, Inc.  All Rights Reserved.
  12 */
  13
  14#include <linux/ctype.h>
  15#include <linux/types.h>
  16#include <linux/string.h>
  17#include <linux/kernel.h>
  18#include <linux/kmsg_dump.h>
  19#include <linux/reboot.h>
  20#include <linux/sched.h>
  21#include <linux/sched/loadavg.h>
  22#include <linux/sched/stat.h>
  23#include <linux/sched/debug.h>
  24#include <linux/sysrq.h>
  25#include <linux/smp.h>
  26#include <linux/utsname.h>
  27#include <linux/vmalloc.h>
  28#include <linux/atomic.h>
  29#include <linux/module.h>
  30#include <linux/moduleparam.h>
  31#include <linux/mm.h>
  32#include <linux/init.h>
  33#include <linux/kallsyms.h>
  34#include <linux/kgdb.h>
  35#include <linux/kdb.h>
  36#include <linux/list.h>
  37#include <linux/notifier.h>
  38#include <linux/interrupt.h>
  39#include <linux/delay.h>
  40#include <linux/nmi.h>
  41#include <linux/time.h>
  42#include <linux/ptrace.h>
  43#include <linux/sysctl.h>
  44#include <linux/cpu.h>
  45#include <linux/kdebug.h>
  46#include <linux/proc_fs.h>
  47#include <linux/uaccess.h>
  48#include <linux/slab.h>
 
  49#include "kdb_private.h"
  50
  51#undef	MODULE_PARAM_PREFIX
  52#define	MODULE_PARAM_PREFIX "kdb."
  53
  54static int kdb_cmd_enabled = CONFIG_KDB_DEFAULT_ENABLE;
  55module_param_named(cmd_enable, kdb_cmd_enabled, int, 0600);
  56
  57char kdb_grep_string[KDB_GREP_STRLEN];
  58int kdb_grepping_flag;
  59EXPORT_SYMBOL(kdb_grepping_flag);
  60int kdb_grep_leading;
  61int kdb_grep_trailing;
  62
  63/*
  64 * Kernel debugger state flags
  65 */
  66unsigned int kdb_flags;
  67
  68/*
  69 * kdb_lock protects updates to kdb_initial_cpu.  Used to
  70 * single thread processors through the kernel debugger.
  71 */
  72int kdb_initial_cpu = -1;	/* cpu number that owns kdb */
  73int kdb_nextline = 1;
  74int kdb_state;			/* General KDB state */
  75
  76struct task_struct *kdb_current_task;
  77struct pt_regs *kdb_current_regs;
  78
  79const char *kdb_diemsg;
  80static int kdb_go_count;
  81#ifdef CONFIG_KDB_CONTINUE_CATASTROPHIC
  82static unsigned int kdb_continue_catastrophic =
  83	CONFIG_KDB_CONTINUE_CATASTROPHIC;
  84#else
  85static unsigned int kdb_continue_catastrophic;
  86#endif
  87
  88/* kdb_cmds_head describes the available commands. */
  89static LIST_HEAD(kdb_cmds_head);
  90
  91typedef struct _kdbmsg {
  92	int	km_diag;	/* kdb diagnostic */
  93	char	*km_msg;	/* Corresponding message text */
  94} kdbmsg_t;
  95
  96#define KDBMSG(msgnum, text) \
  97	{ KDB_##msgnum, text }
  98
  99static kdbmsg_t kdbmsgs[] = {
 100	KDBMSG(NOTFOUND, "Command Not Found"),
 101	KDBMSG(ARGCOUNT, "Improper argument count, see usage."),
 102	KDBMSG(BADWIDTH, "Illegal value for BYTESPERWORD use 1, 2, 4 or 8, "
 103	       "8 is only allowed on 64 bit systems"),
 104	KDBMSG(BADRADIX, "Illegal value for RADIX use 8, 10 or 16"),
 105	KDBMSG(NOTENV, "Cannot find environment variable"),
 106	KDBMSG(NOENVVALUE, "Environment variable should have value"),
 107	KDBMSG(NOTIMP, "Command not implemented"),
 108	KDBMSG(ENVFULL, "Environment full"),
 109	KDBMSG(ENVBUFFULL, "Environment buffer full"),
 110	KDBMSG(TOOMANYBPT, "Too many breakpoints defined"),
 111#ifdef CONFIG_CPU_XSCALE
 112	KDBMSG(TOOMANYDBREGS, "More breakpoints than ibcr registers defined"),
 113#else
 114	KDBMSG(TOOMANYDBREGS, "More breakpoints than db registers defined"),
 115#endif
 116	KDBMSG(DUPBPT, "Duplicate breakpoint address"),
 117	KDBMSG(BPTNOTFOUND, "Breakpoint not found"),
 118	KDBMSG(BADMODE, "Invalid IDMODE"),
 119	KDBMSG(BADINT, "Illegal numeric value"),
 120	KDBMSG(INVADDRFMT, "Invalid symbolic address format"),
 121	KDBMSG(BADREG, "Invalid register name"),
 122	KDBMSG(BADCPUNUM, "Invalid cpu number"),
 123	KDBMSG(BADLENGTH, "Invalid length field"),
 124	KDBMSG(NOBP, "No Breakpoint exists"),
 125	KDBMSG(BADADDR, "Invalid address"),
 126	KDBMSG(NOPERM, "Permission denied"),
 127};
 128#undef KDBMSG
 129
 130static const int __nkdb_err = ARRAY_SIZE(kdbmsgs);
 131
 132
 133/*
 134 * Initial environment.   This is all kept static and local to
 135 * this file.   We don't want to rely on the memory allocation
 136 * mechanisms in the kernel, so we use a very limited allocate-only
 137 * heap for new and altered environment variables.  The entire
 138 * environment is limited to a fixed number of entries (add more
 139 * to __env[] if required) and a fixed amount of heap (add more to
 140 * KDB_ENVBUFSIZE if required).
 141 */
 142
 143static char *__env[31] = {
 144#if defined(CONFIG_SMP)
 145	"PROMPT=[%d]kdb> ",
 146#else
 147	"PROMPT=kdb> ",
 148#endif
 149	"MOREPROMPT=more> ",
 150	"RADIX=16",
 151	"MDCOUNT=8",		/* lines of md output */
 152	KDB_PLATFORM_ENV,
 153	"DTABCOUNT=30",
 154	"NOSECT=1",
 155};
 156
 157static const int __nenv = ARRAY_SIZE(__env);
 158
 159struct task_struct *kdb_curr_task(int cpu)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 160{
 161	struct task_struct *p = curr_task(cpu);
 162#ifdef	_TIF_MCA_INIT
 163	if ((task_thread_info(p)->flags & _TIF_MCA_INIT) && KDB_TSK(cpu))
 164		p = krp->p;
 165#endif
 166	return p;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 167}
 168
 169/*
 170 * Check whether the flags of the current command and the permissions
 171 * of the kdb console has allow a command to be run.
 172 */
 173static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 174				   bool no_args)
 175{
 176	/* permissions comes from userspace so needs massaging slightly */
 177	permissions &= KDB_ENABLE_MASK;
 178	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 179
 180	/* some commands change group when launched with no arguments */
 181	if (no_args)
 182		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 183
 184	flags |= KDB_ENABLE_ALL;
 185
 186	return permissions & flags;
 187}
 188
 189/*
 190 * kdbgetenv - This function will return the character string value of
 191 *	an environment variable.
 192 * Parameters:
 193 *	match	A character string representing an environment variable.
 194 * Returns:
 195 *	NULL	No environment variable matches 'match'
 196 *	char*	Pointer to string value of environment variable.
 197 */
 198char *kdbgetenv(const char *match)
 199{
 200	char **ep = __env;
 201	int matchlen = strlen(match);
 202	int i;
 203
 204	for (i = 0; i < __nenv; i++) {
 205		char *e = *ep++;
 206
 207		if (!e)
 208			continue;
 209
 210		if ((strncmp(match, e, matchlen) == 0)
 211		 && ((e[matchlen] == '\0')
 212		   || (e[matchlen] == '='))) {
 213			char *cp = strchr(e, '=');
 214			return cp ? ++cp : "";
 215		}
 216	}
 217	return NULL;
 218}
 219
 220/*
 221 * kdballocenv - This function is used to allocate bytes for
 222 *	environment entries.
 223 * Parameters:
 224 *	match	A character string representing a numeric value
 225 * Outputs:
 226 *	*value  the unsigned long representation of the env variable 'match'
 227 * Returns:
 228 *	Zero on success, a kdb diagnostic on failure.
 
 229 * Remarks:
 230 *	We use a static environment buffer (envbuffer) to hold the values
 231 *	of dynamically generated environment variables (see kdb_set).  Buffer
 232 *	space once allocated is never free'd, so over time, the amount of space
 233 *	(currently 512 bytes) will be exhausted if env variables are changed
 234 *	frequently.
 235 */
 236static char *kdballocenv(size_t bytes)
 237{
 238#define	KDB_ENVBUFSIZE	512
 239	static char envbuffer[KDB_ENVBUFSIZE];
 240	static int envbufsize;
 241	char *ep = NULL;
 242
 243	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 244		ep = &envbuffer[envbufsize];
 245		envbufsize += bytes;
 246	}
 247	return ep;
 248}
 249
 250/*
 251 * kdbgetulenv - This function will return the value of an unsigned
 252 *	long-valued environment variable.
 253 * Parameters:
 254 *	match	A character string representing a numeric value
 255 * Outputs:
 256 *	*value  the unsigned long representation of the env variable 'match'
 257 * Returns:
 258 *	Zero on success, a kdb diagnostic on failure.
 259 */
 260static int kdbgetulenv(const char *match, unsigned long *value)
 261{
 262	char *ep;
 263
 264	ep = kdbgetenv(match);
 265	if (!ep)
 266		return KDB_NOTENV;
 267	if (strlen(ep) == 0)
 268		return KDB_NOENVVALUE;
 269
 270	*value = simple_strtoul(ep, NULL, 0);
 271
 272	return 0;
 273}
 274
 275/*
 276 * kdbgetintenv - This function will return the value of an
 277 *	integer-valued environment variable.
 278 * Parameters:
 279 *	match	A character string representing an integer-valued env variable
 280 * Outputs:
 281 *	*value  the integer representation of the environment variable 'match'
 282 * Returns:
 283 *	Zero on success, a kdb diagnostic on failure.
 284 */
 285int kdbgetintenv(const char *match, int *value)
 286{
 287	unsigned long val;
 288	int diag;
 289
 290	diag = kdbgetulenv(match, &val);
 291	if (!diag)
 292		*value = (int) val;
 293	return diag;
 294}
 295
 296/*
 297 * kdb_setenv() - Alter an existing environment variable or create a new one.
 298 * @var: Name of the variable
 299 * @val: Value of the variable
 300 *
 301 * Return: Zero on success, a kdb diagnostic on failure.
 302 */
 303static int kdb_setenv(const char *var, const char *val)
 304{
 305	int i;
 306	char *ep;
 307	size_t varlen, vallen;
 308
 309	varlen = strlen(var);
 310	vallen = strlen(val);
 311	ep = kdballocenv(varlen + vallen + 2);
 312	if (ep == (char *)0)
 313		return KDB_ENVBUFFULL;
 314
 315	sprintf(ep, "%s=%s", var, val);
 316
 317	for (i = 0; i < __nenv; i++) {
 318		if (__env[i]
 319		 && ((strncmp(__env[i], var, varlen) == 0)
 320		   && ((__env[i][varlen] == '\0')
 321		    || (__env[i][varlen] == '=')))) {
 322			__env[i] = ep;
 323			return 0;
 324		}
 325	}
 326
 327	/*
 328	 * Wasn't existing variable.  Fit into slot.
 329	 */
 330	for (i = 0; i < __nenv-1; i++) {
 331		if (__env[i] == (char *)0) {
 332			__env[i] = ep;
 333			return 0;
 334		}
 335	}
 336
 337	return KDB_ENVFULL;
 338}
 339
 340/*
 341 * kdb_printenv() - Display the current environment variables.
 342 */
 343static void kdb_printenv(void)
 344{
 345	int i;
 346
 347	for (i = 0; i < __nenv; i++) {
 348		if (__env[i])
 349			kdb_printf("%s\n", __env[i]);
 350	}
 351}
 352
 353/*
 354 * kdbgetularg - This function will convert a numeric string into an
 355 *	unsigned long value.
 356 * Parameters:
 357 *	arg	A character string representing a numeric value
 358 * Outputs:
 359 *	*value  the unsigned long representation of arg.
 360 * Returns:
 361 *	Zero on success, a kdb diagnostic on failure.
 362 */
 363int kdbgetularg(const char *arg, unsigned long *value)
 364{
 365	char *endp;
 366	unsigned long val;
 367
 368	val = simple_strtoul(arg, &endp, 0);
 369
 370	if (endp == arg) {
 371		/*
 372		 * Also try base 16, for us folks too lazy to type the
 373		 * leading 0x...
 374		 */
 375		val = simple_strtoul(arg, &endp, 16);
 376		if (endp == arg)
 377			return KDB_BADINT;
 378	}
 379
 380	*value = val;
 381
 382	return 0;
 383}
 384
 385int kdbgetu64arg(const char *arg, u64 *value)
 386{
 387	char *endp;
 388	u64 val;
 389
 390	val = simple_strtoull(arg, &endp, 0);
 391
 392	if (endp == arg) {
 393
 394		val = simple_strtoull(arg, &endp, 16);
 395		if (endp == arg)
 396			return KDB_BADINT;
 397	}
 398
 399	*value = val;
 400
 401	return 0;
 402}
 403
 404/*
 405 * kdb_set - This function implements the 'set' command.  Alter an
 406 *	existing environment variable or create a new one.
 407 */
 408int kdb_set(int argc, const char **argv)
 409{
 410	/*
 411	 * we can be invoked two ways:
 412	 *   set var=value    argv[1]="var", argv[2]="value"
 413	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 414	 * - if the latter, shift 'em down.
 415	 */
 416	if (argc == 3) {
 417		argv[2] = argv[3];
 418		argc--;
 419	}
 420
 421	if (argc != 2)
 422		return KDB_ARGCOUNT;
 423
 424	/*
 425	 * Censor sensitive variables
 426	 */
 427	if (strcmp(argv[1], "PROMPT") == 0 &&
 428	    !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
 429		return KDB_NOPERM;
 430
 431	/*
 432	 * Check for internal variables
 433	 */
 434	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 435		unsigned int debugflags;
 436		char *cp;
 437
 438		debugflags = simple_strtoul(argv[2], &cp, 0);
 439		if (cp == argv[2] || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 440			kdb_printf("kdb: illegal debug flags '%s'\n",
 441				    argv[2]);
 442			return 0;
 443		}
 444		kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
 445			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 446
 447		return 0;
 448	}
 449
 450	/*
 451	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 452	 * name, argv[2] = value.
 453	 */
 454	return kdb_setenv(argv[1], argv[2]);
 455}
 456
 457static int kdb_check_regs(void)
 458{
 459	if (!kdb_current_regs) {
 460		kdb_printf("No current kdb registers."
 461			   "  You may need to select another task\n");
 462		return KDB_BADREG;
 463	}
 464	return 0;
 465}
 466
 467/*
 468 * kdbgetaddrarg - This function is responsible for parsing an
 469 *	address-expression and returning the value of the expression,
 470 *	symbol name, and offset to the caller.
 471 *
 472 *	The argument may consist of a numeric value (decimal or
 473 *	hexadecimal), a symbol name, a register name (preceded by the
 474 *	percent sign), an environment variable with a numeric value
 475 *	(preceded by a dollar sign) or a simple arithmetic expression
 476 *	consisting of a symbol name, +/-, and a numeric constant value
 477 *	(offset).
 478 * Parameters:
 479 *	argc	- count of arguments in argv
 480 *	argv	- argument vector
 481 *	*nextarg - index to next unparsed argument in argv[]
 482 *	regs	- Register state at time of KDB entry
 483 * Outputs:
 484 *	*value	- receives the value of the address-expression
 485 *	*offset - receives the offset specified, if any
 486 *	*name   - receives the symbol name, if any
 487 *	*nextarg - index to next unparsed argument in argv[]
 488 * Returns:
 489 *	zero is returned on success, a kdb diagnostic code is
 490 *      returned on error.
 491 */
 492int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 493		  unsigned long *value,  long *offset,
 494		  char **name)
 495{
 496	unsigned long addr;
 497	unsigned long off = 0;
 498	int positive;
 499	int diag;
 500	int found = 0;
 501	char *symname;
 502	char symbol = '\0';
 503	char *cp;
 504	kdb_symtab_t symtab;
 505
 506	/*
 507	 * If the enable flags prohibit both arbitrary memory access
 508	 * and flow control then there are no reasonable grounds to
 509	 * provide symbol lookup.
 510	 */
 511	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 512			     kdb_cmd_enabled, false))
 513		return KDB_NOPERM;
 514
 515	/*
 516	 * Process arguments which follow the following syntax:
 517	 *
 518	 *  symbol | numeric-address [+/- numeric-offset]
 519	 *  %register
 520	 *  $environment-variable
 521	 */
 522
 523	if (*nextarg > argc)
 524		return KDB_ARGCOUNT;
 525
 526	symname = (char *)argv[*nextarg];
 527
 528	/*
 529	 * If there is no whitespace between the symbol
 530	 * or address and the '+' or '-' symbols, we
 531	 * remember the character and replace it with a
 532	 * null so the symbol/value can be properly parsed
 533	 */
 534	cp = strpbrk(symname, "+-");
 535	if (cp != NULL) {
 536		symbol = *cp;
 537		*cp++ = '\0';
 538	}
 539
 540	if (symname[0] == '$') {
 541		diag = kdbgetulenv(&symname[1], &addr);
 542		if (diag)
 543			return diag;
 544	} else if (symname[0] == '%') {
 545		diag = kdb_check_regs();
 546		if (diag)
 547			return diag;
 548		/* Implement register values with % at a later time as it is
 549		 * arch optional.
 550		 */
 551		return KDB_NOTIMP;
 552	} else {
 553		found = kdbgetsymval(symname, &symtab);
 554		if (found) {
 555			addr = symtab.sym_start;
 556		} else {
 557			diag = kdbgetularg(argv[*nextarg], &addr);
 558			if (diag)
 559				return diag;
 560		}
 561	}
 562
 563	if (!found)
 564		found = kdbnearsym(addr, &symtab);
 565
 566	(*nextarg)++;
 567
 568	if (name)
 569		*name = symname;
 570	if (value)
 571		*value = addr;
 572	if (offset && name && *name)
 573		*offset = addr - symtab.sym_start;
 574
 575	if ((*nextarg > argc)
 576	 && (symbol == '\0'))
 577		return 0;
 578
 579	/*
 580	 * check for +/- and offset
 581	 */
 582
 583	if (symbol == '\0') {
 584		if ((argv[*nextarg][0] != '+')
 585		 && (argv[*nextarg][0] != '-')) {
 586			/*
 587			 * Not our argument.  Return.
 588			 */
 589			return 0;
 590		} else {
 591			positive = (argv[*nextarg][0] == '+');
 592			(*nextarg)++;
 593		}
 594	} else
 595		positive = (symbol == '+');
 596
 597	/*
 598	 * Now there must be an offset!
 599	 */
 600	if ((*nextarg > argc)
 601	 && (symbol == '\0')) {
 602		return KDB_INVADDRFMT;
 603	}
 604
 605	if (!symbol) {
 606		cp = (char *)argv[*nextarg];
 607		(*nextarg)++;
 608	}
 609
 610	diag = kdbgetularg(cp, &off);
 611	if (diag)
 612		return diag;
 613
 614	if (!positive)
 615		off = -off;
 616
 617	if (offset)
 618		*offset += off;
 619
 620	if (value)
 621		*value += off;
 622
 623	return 0;
 624}
 625
 626static void kdb_cmderror(int diag)
 627{
 628	int i;
 629
 630	if (diag >= 0) {
 631		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 632		return;
 633	}
 634
 635	for (i = 0; i < __nkdb_err; i++) {
 636		if (kdbmsgs[i].km_diag == diag) {
 637			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 638			return;
 639		}
 640	}
 641
 642	kdb_printf("Unknown diag %d\n", -diag);
 643}
 644
 645/*
 646 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 647 *	command which defines one command as a set of other commands,
 648 *	terminated by endefcmd.  kdb_defcmd processes the initial
 649 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 650 *	the following commands until 'endefcmd'.
 651 * Inputs:
 652 *	argc	argument count
 653 *	argv	argument vector
 654 * Returns:
 655 *	zero for success, a kdb diagnostic if error
 656 */
 657struct defcmd_set {
 658	int count;
 659	bool usable;
 660	char *name;
 661	char *usage;
 662	char *help;
 663	char **command;
 
 664};
 665static struct defcmd_set *defcmd_set;
 666static int defcmd_set_count;
 667static bool defcmd_in_progress;
 668
 669/* Forward references */
 670static int kdb_exec_defcmd(int argc, const char **argv);
 671
 672static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 673{
 674	struct defcmd_set *s = defcmd_set + defcmd_set_count - 1;
 675	char **save_command = s->command;
 
 
 
 676	if (strcmp(argv0, "endefcmd") == 0) {
 677		defcmd_in_progress = false;
 678		if (!s->count)
 679			s->usable = false;
 680		if (s->usable)
 681			/* macros are always safe because when executed each
 682			 * internal command re-enters kdb_parse() and is
 683			 * safety checked individually.
 684			 */
 685			kdb_register_flags(s->name, kdb_exec_defcmd, s->usage,
 686					   s->help, 0,
 687					   KDB_ENABLE_ALWAYS_SAFE);
 688		return 0;
 689	}
 690	if (!s->usable)
 691		return KDB_NOTIMP;
 692	s->command = kcalloc(s->count + 1, sizeof(*(s->command)), GFP_KDB);
 693	if (!s->command) {
 694		kdb_printf("Could not allocate new kdb_defcmd table for %s\n",
 695			   cmdstr);
 696		s->usable = false;
 697		return KDB_NOTIMP;
 698	}
 699	memcpy(s->command, save_command, s->count * sizeof(*(s->command)));
 700	s->command[s->count++] = kdb_strdup(cmdstr, GFP_KDB);
 701	kfree(save_command);
 
 702	return 0;
 703}
 704
 705static int kdb_defcmd(int argc, const char **argv)
 706{
 707	struct defcmd_set *save_defcmd_set = defcmd_set, *s;
 
 708	if (defcmd_in_progress) {
 709		kdb_printf("kdb: nested defcmd detected, assuming missing "
 710			   "endefcmd\n");
 711		kdb_defcmd2("endefcmd", "endefcmd");
 712	}
 713	if (argc == 0) {
 714		int i;
 715		for (s = defcmd_set; s < defcmd_set + defcmd_set_count; ++s) {
 716			kdb_printf("defcmd %s \"%s\" \"%s\"\n", s->name,
 717				   s->usage, s->help);
 718			for (i = 0; i < s->count; ++i)
 719				kdb_printf("%s", s->command[i]);
 720			kdb_printf("endefcmd\n");
 
 
 
 
 
 
 
 721		}
 722		return 0;
 723	}
 724	if (argc != 3)
 725		return KDB_ARGCOUNT;
 726	if (in_dbg_master()) {
 727		kdb_printf("Command only available during kdb_init()\n");
 728		return KDB_NOTIMP;
 729	}
 730	defcmd_set = kmalloc_array(defcmd_set_count + 1, sizeof(*defcmd_set),
 731				   GFP_KDB);
 732	if (!defcmd_set)
 733		goto fail_defcmd;
 734	memcpy(defcmd_set, save_defcmd_set,
 735	       defcmd_set_count * sizeof(*defcmd_set));
 736	s = defcmd_set + defcmd_set_count;
 737	memset(s, 0, sizeof(*s));
 738	s->usable = true;
 739	s->name = kdb_strdup(argv[1], GFP_KDB);
 740	if (!s->name)
 741		goto fail_name;
 742	s->usage = kdb_strdup(argv[2], GFP_KDB);
 743	if (!s->usage)
 744		goto fail_usage;
 745	s->help = kdb_strdup(argv[3], GFP_KDB);
 746	if (!s->help)
 747		goto fail_help;
 748	if (s->usage[0] == '"') {
 749		strcpy(s->usage, argv[2]+1);
 750		s->usage[strlen(s->usage)-1] = '\0';
 751	}
 752	if (s->help[0] == '"') {
 753		strcpy(s->help, argv[3]+1);
 754		s->help[strlen(s->help)-1] = '\0';
 755	}
 756	++defcmd_set_count;
 
 757	defcmd_in_progress = true;
 758	kfree(save_defcmd_set);
 759	return 0;
 760fail_help:
 761	kfree(s->usage);
 762fail_usage:
 763	kfree(s->name);
 764fail_name:
 765	kfree(defcmd_set);
 766fail_defcmd:
 767	kdb_printf("Could not allocate new defcmd_set entry for %s\n", argv[1]);
 768	defcmd_set = save_defcmd_set;
 769	return KDB_NOTIMP;
 770}
 771
 772/*
 773 * kdb_exec_defcmd - Execute the set of commands associated with this
 774 *	defcmd name.
 775 * Inputs:
 776 *	argc	argument count
 777 *	argv	argument vector
 778 * Returns:
 779 *	zero for success, a kdb diagnostic if error
 780 */
 781static int kdb_exec_defcmd(int argc, const char **argv)
 782{
 783	int i, ret;
 784	struct defcmd_set *s;
 
 
 
 785	if (argc != 0)
 786		return KDB_ARGCOUNT;
 787	for (s = defcmd_set, i = 0; i < defcmd_set_count; ++i, ++s) {
 788		if (strcmp(s->name, argv[0]) == 0)
 
 789			break;
 790	}
 791	if (i == defcmd_set_count) {
 792		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 793			   argv[0]);
 794		return KDB_NOTIMP;
 795	}
 796	for (i = 0; i < s->count; ++i) {
 797		/* Recursive use of kdb_parse, do not use argv after
 798		 * this point */
 
 
 799		argv = NULL;
 800		kdb_printf("[%s]kdb> %s\n", s->name, s->command[i]);
 801		ret = kdb_parse(s->command[i]);
 802		if (ret)
 803			return ret;
 804	}
 805	return 0;
 806}
 807
 808/* Command history */
 809#define KDB_CMD_HISTORY_COUNT	32
 810#define CMD_BUFLEN		200	/* kdb_printf: max printline
 811					 * size == 256 */
 812static unsigned int cmd_head, cmd_tail;
 813static unsigned int cmdptr;
 814static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 815static char cmd_cur[CMD_BUFLEN];
 816
 817/*
 818 * The "str" argument may point to something like  | grep xyz
 819 */
 820static void parse_grep(const char *str)
 821{
 822	int	len;
 823	char	*cp = (char *)str, *cp2;
 824
 825	/* sanity check: we should have been called with the \ first */
 826	if (*cp != '|')
 827		return;
 828	cp++;
 829	while (isspace(*cp))
 830		cp++;
 831	if (!str_has_prefix(cp, "grep ")) {
 832		kdb_printf("invalid 'pipe', see grephelp\n");
 833		return;
 834	}
 835	cp += 5;
 836	while (isspace(*cp))
 837		cp++;
 838	cp2 = strchr(cp, '\n');
 839	if (cp2)
 840		*cp2 = '\0'; /* remove the trailing newline */
 841	len = strlen(cp);
 842	if (len == 0) {
 843		kdb_printf("invalid 'pipe', see grephelp\n");
 844		return;
 845	}
 846	/* now cp points to a nonzero length search string */
 847	if (*cp == '"') {
 848		/* allow it be "x y z" by removing the "'s - there must
 849		   be two of them */
 850		cp++;
 851		cp2 = strchr(cp, '"');
 852		if (!cp2) {
 853			kdb_printf("invalid quoted string, see grephelp\n");
 854			return;
 855		}
 856		*cp2 = '\0'; /* end the string where the 2nd " was */
 857	}
 858	kdb_grep_leading = 0;
 859	if (*cp == '^') {
 860		kdb_grep_leading = 1;
 861		cp++;
 862	}
 863	len = strlen(cp);
 864	kdb_grep_trailing = 0;
 865	if (*(cp+len-1) == '$') {
 866		kdb_grep_trailing = 1;
 867		*(cp+len-1) = '\0';
 868	}
 869	len = strlen(cp);
 870	if (!len)
 871		return;
 872	if (len >= KDB_GREP_STRLEN) {
 873		kdb_printf("search string too long\n");
 874		return;
 875	}
 876	strcpy(kdb_grep_string, cp);
 877	kdb_grepping_flag++;
 878	return;
 879}
 880
 881/*
 882 * kdb_parse - Parse the command line, search the command table for a
 883 *	matching command and invoke the command function.  This
 884 *	function may be called recursively, if it is, the second call
 885 *	will overwrite argv and cbuf.  It is the caller's
 886 *	responsibility to save their argv if they recursively call
 887 *	kdb_parse().
 888 * Parameters:
 889 *      cmdstr	The input command line to be parsed.
 890 *	regs	The registers at the time kdb was entered.
 891 * Returns:
 892 *	Zero for success, a kdb diagnostic if failure.
 893 * Remarks:
 894 *	Limited to 20 tokens.
 895 *
 896 *	Real rudimentary tokenization. Basically only whitespace
 897 *	is considered a token delimiter (but special consideration
 898 *	is taken of the '=' sign as used by the 'set' command).
 899 *
 900 *	The algorithm used to tokenize the input string relies on
 901 *	there being at least one whitespace (or otherwise useless)
 902 *	character between tokens as the character immediately following
 903 *	the token is altered in-place to a null-byte to terminate the
 904 *	token string.
 905 */
 906
 907#define MAXARGC	20
 908
 909int kdb_parse(const char *cmdstr)
 910{
 911	static char *argv[MAXARGC];
 912	static int argc;
 913	static char cbuf[CMD_BUFLEN+2];
 914	char *cp;
 915	char *cpp, quoted;
 916	kdbtab_t *tp;
 917	int escaped, ignore_errors = 0, check_grep = 0;
 918
 919	/*
 920	 * First tokenize the command string.
 921	 */
 922	cp = (char *)cmdstr;
 923
 924	if (KDB_FLAG(CMD_INTERRUPT)) {
 925		/* Previous command was interrupted, newline must not
 926		 * repeat the command */
 927		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 928		KDB_STATE_SET(PAGER);
 929		argc = 0;	/* no repeat */
 930	}
 931
 932	if (*cp != '\n' && *cp != '\0') {
 933		argc = 0;
 934		cpp = cbuf;
 935		while (*cp) {
 936			/* skip whitespace */
 937			while (isspace(*cp))
 938				cp++;
 939			if ((*cp == '\0') || (*cp == '\n') ||
 940			    (*cp == '#' && !defcmd_in_progress))
 941				break;
 942			/* special case: check for | grep pattern */
 943			if (*cp == '|') {
 944				check_grep++;
 945				break;
 946			}
 947			if (cpp >= cbuf + CMD_BUFLEN) {
 948				kdb_printf("kdb_parse: command buffer "
 949					   "overflow, command ignored\n%s\n",
 950					   cmdstr);
 951				return KDB_NOTFOUND;
 952			}
 953			if (argc >= MAXARGC - 1) {
 954				kdb_printf("kdb_parse: too many arguments, "
 955					   "command ignored\n%s\n", cmdstr);
 956				return KDB_NOTFOUND;
 957			}
 958			argv[argc++] = cpp;
 959			escaped = 0;
 960			quoted = '\0';
 961			/* Copy to next unquoted and unescaped
 962			 * whitespace or '=' */
 963			while (*cp && *cp != '\n' &&
 964			       (escaped || quoted || !isspace(*cp))) {
 965				if (cpp >= cbuf + CMD_BUFLEN)
 966					break;
 967				if (escaped) {
 968					escaped = 0;
 969					*cpp++ = *cp++;
 970					continue;
 971				}
 972				if (*cp == '\\') {
 973					escaped = 1;
 974					++cp;
 975					continue;
 976				}
 977				if (*cp == quoted)
 978					quoted = '\0';
 979				else if (*cp == '\'' || *cp == '"')
 980					quoted = *cp;
 981				*cpp = *cp++;
 982				if (*cpp == '=' && !quoted)
 983					break;
 984				++cpp;
 985			}
 986			*cpp++ = '\0';	/* Squash a ws or '=' character */
 987		}
 988	}
 989	if (!argc)
 990		return 0;
 991	if (check_grep)
 992		parse_grep(cp);
 993	if (defcmd_in_progress) {
 994		int result = kdb_defcmd2(cmdstr, argv[0]);
 995		if (!defcmd_in_progress) {
 996			argc = 0;	/* avoid repeat on endefcmd */
 997			*(argv[0]) = '\0';
 998		}
 999		return result;
1000	}
1001	if (argv[0][0] == '-' && argv[0][1] &&
1002	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1003		ignore_errors = 1;
1004		++argv[0];
1005	}
1006
1007	list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1008		/*
1009		 * If this command is allowed to be abbreviated,
1010		 * check to see if this is it.
1011		 */
1012		if (tp->cmd_minlen && (strlen(argv[0]) <= tp->cmd_minlen) &&
1013		    (strncmp(argv[0], tp->cmd_name, tp->cmd_minlen) == 0))
1014			break;
1015
1016		if (strcmp(argv[0], tp->cmd_name) == 0)
1017			break;
1018	}
1019
1020	/*
1021	 * If we don't find a command by this name, see if the first
1022	 * few characters of this match any of the known commands.
1023	 * e.g., md1c20 should match md.
1024	 */
1025	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1026		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1027			if (strncmp(argv[0], tp->cmd_name,
1028				    strlen(tp->cmd_name)) == 0)
1029				break;
1030		}
1031	}
1032
1033	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1034		int result;
1035
1036		if (!kdb_check_flags(tp->cmd_flags, kdb_cmd_enabled, argc <= 1))
1037			return KDB_NOPERM;
1038
1039		KDB_STATE_SET(CMD);
1040		result = (*tp->cmd_func)(argc-1, (const char **)argv);
1041		if (result && ignore_errors && result > KDB_CMD_GO)
1042			result = 0;
1043		KDB_STATE_CLEAR(CMD);
1044
1045		if (tp->cmd_flags & KDB_REPEAT_WITH_ARGS)
1046			return result;
1047
1048		argc = tp->cmd_flags & KDB_REPEAT_NO_ARGS ? 1 : 0;
1049		if (argv[argc])
1050			*(argv[argc]) = '\0';
1051		return result;
1052	}
1053
1054	/*
1055	 * If the input with which we were presented does not
1056	 * map to an existing command, attempt to parse it as an
1057	 * address argument and display the result.   Useful for
1058	 * obtaining the address of a variable, or the nearest symbol
1059	 * to an address contained in a register.
1060	 */
1061	{
1062		unsigned long value;
1063		char *name = NULL;
1064		long offset;
1065		int nextarg = 0;
1066
1067		if (kdbgetaddrarg(0, (const char **)argv, &nextarg,
1068				  &value, &offset, &name)) {
1069			return KDB_NOTFOUND;
1070		}
1071
1072		kdb_printf("%s = ", argv[0]);
1073		kdb_symbol_print(value, NULL, KDB_SP_DEFAULT);
1074		kdb_printf("\n");
1075		return 0;
1076	}
1077}
1078
1079
1080static int handle_ctrl_cmd(char *cmd)
1081{
1082#define CTRL_P	16
1083#define CTRL_N	14
1084
1085	/* initial situation */
1086	if (cmd_head == cmd_tail)
1087		return 0;
1088	switch (*cmd) {
1089	case CTRL_P:
1090		if (cmdptr != cmd_tail)
1091			cmdptr = (cmdptr + KDB_CMD_HISTORY_COUNT - 1) %
1092				 KDB_CMD_HISTORY_COUNT;
1093		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1094		return 1;
1095	case CTRL_N:
1096		if (cmdptr != cmd_head)
1097			cmdptr = (cmdptr+1) % KDB_CMD_HISTORY_COUNT;
1098		strscpy(cmd_cur, cmd_hist[cmdptr], CMD_BUFLEN);
1099		return 1;
1100	}
1101	return 0;
1102}
1103
1104/*
1105 * kdb_reboot - This function implements the 'reboot' command.  Reboot
1106 *	the system immediately, or loop for ever on failure.
1107 */
1108static int kdb_reboot(int argc, const char **argv)
1109{
1110	emergency_restart();
1111	kdb_printf("Hmm, kdb_reboot did not reboot, spinning here\n");
1112	while (1)
1113		cpu_relax();
1114	/* NOTREACHED */
1115	return 0;
1116}
1117
1118static void kdb_dumpregs(struct pt_regs *regs)
1119{
1120	int old_lvl = console_loglevel;
1121	console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
1122	kdb_trap_printk++;
1123	show_regs(regs);
1124	kdb_trap_printk--;
1125	kdb_printf("\n");
1126	console_loglevel = old_lvl;
1127}
1128
1129static void kdb_set_current_task(struct task_struct *p)
1130{
1131	kdb_current_task = p;
1132
1133	if (kdb_task_has_cpu(p)) {
1134		kdb_current_regs = KDB_TSKREGS(kdb_process_cpu(p));
1135		return;
1136	}
1137	kdb_current_regs = NULL;
1138}
1139
1140static void drop_newline(char *buf)
1141{
1142	size_t len = strlen(buf);
1143
1144	if (len == 0)
1145		return;
1146	if (*(buf + len - 1) == '\n')
1147		*(buf + len - 1) = '\0';
1148}
1149
1150/*
1151 * kdb_local - The main code for kdb.  This routine is invoked on a
1152 *	specific processor, it is not global.  The main kdb() routine
1153 *	ensures that only one processor at a time is in this routine.
1154 *	This code is called with the real reason code on the first
1155 *	entry to a kdb session, thereafter it is called with reason
1156 *	SWITCH, even if the user goes back to the original cpu.
1157 * Inputs:
1158 *	reason		The reason KDB was invoked
1159 *	error		The hardware-defined error code
1160 *	regs		The exception frame at time of fault/breakpoint.
1161 *	db_result	Result code from the break or debug point.
1162 * Returns:
1163 *	0	KDB was invoked for an event which it wasn't responsible
1164 *	1	KDB handled the event for which it was invoked.
1165 *	KDB_CMD_GO	User typed 'go'.
1166 *	KDB_CMD_CPU	User switched to another cpu.
1167 *	KDB_CMD_SS	Single step.
1168 */
1169static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs,
1170		     kdb_dbtrap_t db_result)
1171{
1172	char *cmdbuf;
1173	int diag;
1174	struct task_struct *kdb_current =
1175		kdb_curr_task(raw_smp_processor_id());
1176
1177	KDB_DEBUG_STATE("kdb_local 1", reason);
 
 
 
1178	kdb_go_count = 0;
1179	if (reason == KDB_REASON_DEBUG) {
1180		/* special case below */
1181	} else {
1182		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1183			   kdb_current, kdb_current ? kdb_current->pid : 0);
1184#if defined(CONFIG_SMP)
1185		kdb_printf("on processor %d ", raw_smp_processor_id());
1186#endif
1187	}
1188
1189	switch (reason) {
1190	case KDB_REASON_DEBUG:
1191	{
1192		/*
1193		 * If re-entering kdb after a single step
1194		 * command, don't print the message.
1195		 */
1196		switch (db_result) {
1197		case KDB_DB_BPT:
1198			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1199				   kdb_current, kdb_current->pid);
1200#if defined(CONFIG_SMP)
1201			kdb_printf("on processor %d ", raw_smp_processor_id());
1202#endif
1203			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1204				   instruction_pointer(regs));
1205			break;
1206		case KDB_DB_SS:
1207			break;
1208		case KDB_DB_SSBPT:
1209			KDB_DEBUG_STATE("kdb_local 4", reason);
1210			return 1;	/* kdba_db_trap did the work */
1211		default:
1212			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1213				   db_result);
1214			break;
1215		}
1216
1217	}
1218		break;
1219	case KDB_REASON_ENTER:
1220		if (KDB_STATE(KEYBOARD))
1221			kdb_printf("due to Keyboard Entry\n");
1222		else
1223			kdb_printf("due to KDB_ENTER()\n");
1224		break;
1225	case KDB_REASON_KEYBOARD:
1226		KDB_STATE_SET(KEYBOARD);
1227		kdb_printf("due to Keyboard Entry\n");
1228		break;
1229	case KDB_REASON_ENTER_SLAVE:
1230		/* drop through, slaves only get released via cpu switch */
1231	case KDB_REASON_SWITCH:
1232		kdb_printf("due to cpu switch\n");
1233		break;
1234	case KDB_REASON_OOPS:
1235		kdb_printf("Oops: %s\n", kdb_diemsg);
1236		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1237			   instruction_pointer(regs));
1238		kdb_dumpregs(regs);
1239		break;
1240	case KDB_REASON_SYSTEM_NMI:
1241		kdb_printf("due to System NonMaskable Interrupt\n");
1242		break;
1243	case KDB_REASON_NMI:
1244		kdb_printf("due to NonMaskable Interrupt @ "
1245			   kdb_machreg_fmt "\n",
1246			   instruction_pointer(regs));
1247		break;
1248	case KDB_REASON_SSTEP:
1249	case KDB_REASON_BREAK:
1250		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1251			   reason == KDB_REASON_BREAK ?
1252			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1253		/*
1254		 * Determine if this breakpoint is one that we
1255		 * are interested in.
1256		 */
1257		if (db_result != KDB_DB_BPT) {
1258			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1259				   db_result);
1260			KDB_DEBUG_STATE("kdb_local 6", reason);
1261			return 0;	/* Not for us, dismiss it */
1262		}
1263		break;
1264	case KDB_REASON_RECURSE:
1265		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1266			   instruction_pointer(regs));
1267		break;
1268	default:
1269		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1270		KDB_DEBUG_STATE("kdb_local 8", reason);
1271		return 0;	/* Not for us, dismiss it */
1272	}
1273
1274	while (1) {
1275		/*
1276		 * Initialize pager context.
1277		 */
1278		kdb_nextline = 1;
1279		KDB_STATE_CLEAR(SUPPRESS);
1280		kdb_grepping_flag = 0;
1281		/* ensure the old search does not leak into '/' commands */
1282		kdb_grep_string[0] = '\0';
1283
1284		cmdbuf = cmd_cur;
1285		*cmdbuf = '\0';
1286		*(cmd_hist[cmd_head]) = '\0';
1287
1288do_full_getstr:
1289		/* PROMPT can only be set if we have MEM_READ permission. */
1290		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1291			 raw_smp_processor_id());
1292		if (defcmd_in_progress)
1293			strncat(kdb_prompt_str, "[defcmd]", CMD_BUFLEN);
1294
1295		/*
1296		 * Fetch command from keyboard
1297		 */
1298		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1299		if (*cmdbuf != '\n') {
1300			if (*cmdbuf < 32) {
1301				if (cmdptr == cmd_head) {
1302					strscpy(cmd_hist[cmd_head], cmd_cur,
1303						CMD_BUFLEN);
1304					*(cmd_hist[cmd_head] +
1305					  strlen(cmd_hist[cmd_head])-1) = '\0';
1306				}
1307				if (!handle_ctrl_cmd(cmdbuf))
1308					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1309				cmdbuf = cmd_cur;
1310				goto do_full_getstr;
1311			} else {
1312				strscpy(cmd_hist[cmd_head], cmd_cur,
1313					CMD_BUFLEN);
1314			}
1315
1316			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1317			if (cmd_head == cmd_tail)
1318				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1319		}
1320
1321		cmdptr = cmd_head;
1322		diag = kdb_parse(cmdbuf);
1323		if (diag == KDB_NOTFOUND) {
1324			drop_newline(cmdbuf);
1325			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1326			diag = 0;
1327		}
1328		if (diag == KDB_CMD_GO
1329		 || diag == KDB_CMD_CPU
1330		 || diag == KDB_CMD_SS
1331		 || diag == KDB_CMD_KGDB)
1332			break;
1333
1334		if (diag)
1335			kdb_cmderror(diag);
1336	}
1337	KDB_DEBUG_STATE("kdb_local 9", diag);
1338	return diag;
1339}
1340
1341
1342/*
1343 * kdb_print_state - Print the state data for the current processor
1344 *	for debugging.
1345 * Inputs:
1346 *	text		Identifies the debug point
1347 *	value		Any integer value to be printed, e.g. reason code.
1348 */
1349void kdb_print_state(const char *text, int value)
1350{
1351	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1352		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1353		   kdb_state);
1354}
1355
1356/*
1357 * kdb_main_loop - After initial setup and assignment of the
1358 *	controlling cpu, all cpus are in this loop.  One cpu is in
1359 *	control and will issue the kdb prompt, the others will spin
1360 *	until 'go' or cpu switch.
1361 *
1362 *	To get a consistent view of the kernel stacks for all
1363 *	processes, this routine is invoked from the main kdb code via
1364 *	an architecture specific routine.  kdba_main_loop is
1365 *	responsible for making the kernel stacks consistent for all
1366 *	processes, there should be no difference between a blocked
1367 *	process and a running process as far as kdb is concerned.
1368 * Inputs:
1369 *	reason		The reason KDB was invoked
1370 *	error		The hardware-defined error code
1371 *	reason2		kdb's current reason code.
1372 *			Initially error but can change
1373 *			according to kdb state.
1374 *	db_result	Result code from break or debug point.
1375 *	regs		The exception frame at time of fault/breakpoint.
1376 *			should always be valid.
1377 * Returns:
1378 *	0	KDB was invoked for an event which it wasn't responsible
1379 *	1	KDB handled the event for which it was invoked.
1380 */
1381int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1382	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1383{
1384	int result = 1;
1385	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1386	while (1) {
1387		/*
1388		 * All processors except the one that is in control
1389		 * will spin here.
1390		 */
1391		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1392		while (KDB_STATE(HOLD_CPU)) {
1393			/* state KDB is turned off by kdb_cpu to see if the
1394			 * other cpus are still live, each cpu in this loop
1395			 * turns it back on.
1396			 */
1397			if (!KDB_STATE(KDB))
1398				KDB_STATE_SET(KDB);
1399		}
1400
1401		KDB_STATE_CLEAR(SUPPRESS);
1402		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1403		if (KDB_STATE(LEAVING))
1404			break;	/* Another cpu said 'go' */
1405		/* Still using kdb, this processor is in control */
1406		result = kdb_local(reason2, error, regs, db_result);
1407		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1408
1409		if (result == KDB_CMD_CPU)
1410			break;
1411
1412		if (result == KDB_CMD_SS) {
1413			KDB_STATE_SET(DOING_SS);
1414			break;
1415		}
1416
1417		if (result == KDB_CMD_KGDB) {
1418			if (!KDB_STATE(DOING_KGDB))
1419				kdb_printf("Entering please attach debugger "
1420					   "or use $D#44+ or $3#33\n");
1421			break;
1422		}
1423		if (result && result != 1 && result != KDB_CMD_GO)
1424			kdb_printf("\nUnexpected kdb_local return code %d\n",
1425				   result);
1426		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1427		break;
1428	}
1429	if (KDB_STATE(DOING_SS))
1430		KDB_STATE_CLEAR(SSBPT);
1431
1432	/* Clean up any keyboard devices before leaving */
1433	kdb_kbd_cleanup_state();
1434
1435	return result;
1436}
1437
1438/*
1439 * kdb_mdr - This function implements the guts of the 'mdr', memory
1440 * read command.
1441 *	mdr  <addr arg>,<byte count>
1442 * Inputs:
1443 *	addr	Start address
1444 *	count	Number of bytes
1445 * Returns:
1446 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1447 */
1448static int kdb_mdr(unsigned long addr, unsigned int count)
1449{
1450	unsigned char c;
1451	while (count--) {
1452		if (kdb_getarea(c, addr))
1453			return 0;
1454		kdb_printf("%02x", c);
1455		addr++;
1456	}
1457	kdb_printf("\n");
1458	return 0;
1459}
1460
1461/*
1462 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1463 *	'md8' 'mdr' and 'mds' commands.
1464 *
1465 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1466 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1467 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1468 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1469 *	mdr  <addr arg>,<byte count>
1470 */
1471static void kdb_md_line(const char *fmtstr, unsigned long addr,
1472			int symbolic, int nosect, int bytesperword,
1473			int num, int repeat, int phys)
1474{
1475	/* print just one line of data */
1476	kdb_symtab_t symtab;
1477	char cbuf[32];
1478	char *c = cbuf;
1479	int i;
1480	int j;
1481	unsigned long word;
1482
1483	memset(cbuf, '\0', sizeof(cbuf));
1484	if (phys)
1485		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1486	else
1487		kdb_printf(kdb_machreg_fmt0 " ", addr);
1488
1489	for (i = 0; i < num && repeat--; i++) {
1490		if (phys) {
1491			if (kdb_getphysword(&word, addr, bytesperword))
1492				break;
1493		} else if (kdb_getword(&word, addr, bytesperword))
1494			break;
1495		kdb_printf(fmtstr, word);
1496		if (symbolic)
1497			kdbnearsym(word, &symtab);
1498		else
1499			memset(&symtab, 0, sizeof(symtab));
1500		if (symtab.sym_name) {
1501			kdb_symbol_print(word, &symtab, 0);
1502			if (!nosect) {
1503				kdb_printf("\n");
1504				kdb_printf("                       %s %s "
1505					   kdb_machreg_fmt " "
1506					   kdb_machreg_fmt " "
1507					   kdb_machreg_fmt, symtab.mod_name,
1508					   symtab.sec_name, symtab.sec_start,
1509					   symtab.sym_start, symtab.sym_end);
1510			}
1511			addr += bytesperword;
1512		} else {
1513			union {
1514				u64 word;
1515				unsigned char c[8];
1516			} wc;
1517			unsigned char *cp;
1518#ifdef	__BIG_ENDIAN
1519			cp = wc.c + 8 - bytesperword;
1520#else
1521			cp = wc.c;
1522#endif
1523			wc.word = word;
1524#define printable_char(c) \
1525	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1526			for (j = 0; j < bytesperword; j++)
1527				*c++ = printable_char(*cp++);
1528			addr += bytesperword;
1529#undef printable_char
1530		}
1531	}
1532	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1533		   " ", cbuf);
1534}
1535
1536static int kdb_md(int argc, const char **argv)
1537{
1538	static unsigned long last_addr;
1539	static int last_radix, last_bytesperword, last_repeat;
1540	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1541	int nosect = 0;
1542	char fmtchar, fmtstr[64];
1543	unsigned long addr;
1544	unsigned long word;
1545	long offset = 0;
1546	int symbolic = 0;
1547	int valid = 0;
1548	int phys = 0;
1549	int raw = 0;
1550
1551	kdbgetintenv("MDCOUNT", &mdcount);
1552	kdbgetintenv("RADIX", &radix);
1553	kdbgetintenv("BYTESPERWORD", &bytesperword);
1554
1555	/* Assume 'md <addr>' and start with environment values */
1556	repeat = mdcount * 16 / bytesperword;
1557
1558	if (strcmp(argv[0], "mdr") == 0) {
1559		if (argc == 2 || (argc == 0 && last_addr != 0))
1560			valid = raw = 1;
1561		else
1562			return KDB_ARGCOUNT;
1563	} else if (isdigit(argv[0][2])) {
1564		bytesperword = (int)(argv[0][2] - '0');
1565		if (bytesperword == 0) {
1566			bytesperword = last_bytesperword;
1567			if (bytesperword == 0)
1568				bytesperword = 4;
1569		}
1570		last_bytesperword = bytesperword;
1571		repeat = mdcount * 16 / bytesperword;
1572		if (!argv[0][3])
1573			valid = 1;
1574		else if (argv[0][3] == 'c' && argv[0][4]) {
1575			char *p;
1576			repeat = simple_strtoul(argv[0] + 4, &p, 10);
1577			mdcount = ((repeat * bytesperword) + 15) / 16;
1578			valid = !*p;
1579		}
1580		last_repeat = repeat;
1581	} else if (strcmp(argv[0], "md") == 0)
1582		valid = 1;
1583	else if (strcmp(argv[0], "mds") == 0)
1584		valid = 1;
1585	else if (strcmp(argv[0], "mdp") == 0) {
1586		phys = valid = 1;
1587	}
1588	if (!valid)
1589		return KDB_NOTFOUND;
1590
1591	if (argc == 0) {
1592		if (last_addr == 0)
1593			return KDB_ARGCOUNT;
1594		addr = last_addr;
1595		radix = last_radix;
1596		bytesperword = last_bytesperword;
1597		repeat = last_repeat;
1598		if (raw)
1599			mdcount = repeat;
1600		else
1601			mdcount = ((repeat * bytesperword) + 15) / 16;
1602	}
1603
1604	if (argc) {
1605		unsigned long val;
1606		int diag, nextarg = 1;
1607		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1608				     &offset, NULL);
1609		if (diag)
1610			return diag;
1611		if (argc > nextarg+2)
1612			return KDB_ARGCOUNT;
1613
1614		if (argc >= nextarg) {
1615			diag = kdbgetularg(argv[nextarg], &val);
1616			if (!diag) {
1617				mdcount = (int) val;
1618				if (raw)
1619					repeat = mdcount;
1620				else
1621					repeat = mdcount * 16 / bytesperword;
1622			}
1623		}
1624		if (argc >= nextarg+1) {
1625			diag = kdbgetularg(argv[nextarg+1], &val);
1626			if (!diag)
1627				radix = (int) val;
1628		}
1629	}
1630
1631	if (strcmp(argv[0], "mdr") == 0) {
1632		int ret;
1633		last_addr = addr;
1634		ret = kdb_mdr(addr, mdcount);
1635		last_addr += mdcount;
1636		last_repeat = mdcount;
1637		last_bytesperword = bytesperword; // to make REPEAT happy
1638		return ret;
1639	}
1640
1641	switch (radix) {
1642	case 10:
1643		fmtchar = 'd';
1644		break;
1645	case 16:
1646		fmtchar = 'x';
1647		break;
1648	case 8:
1649		fmtchar = 'o';
1650		break;
1651	default:
1652		return KDB_BADRADIX;
1653	}
1654
1655	last_radix = radix;
1656
1657	if (bytesperword > KDB_WORD_SIZE)
1658		return KDB_BADWIDTH;
1659
1660	switch (bytesperword) {
1661	case 8:
1662		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1663		break;
1664	case 4:
1665		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1666		break;
1667	case 2:
1668		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1669		break;
1670	case 1:
1671		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1672		break;
1673	default:
1674		return KDB_BADWIDTH;
1675	}
1676
1677	last_repeat = repeat;
1678	last_bytesperword = bytesperword;
1679
1680	if (strcmp(argv[0], "mds") == 0) {
1681		symbolic = 1;
1682		/* Do not save these changes as last_*, they are temporary mds
1683		 * overrides.
1684		 */
1685		bytesperword = KDB_WORD_SIZE;
1686		repeat = mdcount;
1687		kdbgetintenv("NOSECT", &nosect);
1688	}
1689
1690	/* Round address down modulo BYTESPERWORD */
1691
1692	addr &= ~(bytesperword-1);
1693
1694	while (repeat > 0) {
1695		unsigned long a;
1696		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1697
1698		if (KDB_FLAG(CMD_INTERRUPT))
1699			return 0;
1700		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1701			if (phys) {
1702				if (kdb_getphysword(&word, a, bytesperword)
1703						|| word)
1704					break;
1705			} else if (kdb_getword(&word, a, bytesperword) || word)
1706				break;
1707		}
1708		n = min(num, repeat);
1709		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1710			    num, repeat, phys);
1711		addr += bytesperword * n;
1712		repeat -= n;
1713		z = (z + num - 1) / num;
1714		if (z > 2) {
1715			int s = num * (z-2);
1716			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1717				   " zero suppressed\n",
1718				addr, addr + bytesperword * s - 1);
1719			addr += bytesperword * s;
1720			repeat -= s;
1721		}
1722	}
1723	last_addr = addr;
1724
1725	return 0;
1726}
1727
1728/*
1729 * kdb_mm - This function implements the 'mm' command.
1730 *	mm address-expression new-value
1731 * Remarks:
1732 *	mm works on machine words, mmW works on bytes.
1733 */
1734static int kdb_mm(int argc, const char **argv)
1735{
1736	int diag;
1737	unsigned long addr;
1738	long offset = 0;
1739	unsigned long contents;
1740	int nextarg;
1741	int width;
1742
1743	if (argv[0][2] && !isdigit(argv[0][2]))
1744		return KDB_NOTFOUND;
1745
1746	if (argc < 2)
1747		return KDB_ARGCOUNT;
1748
1749	nextarg = 1;
1750	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1751	if (diag)
1752		return diag;
1753
1754	if (nextarg > argc)
1755		return KDB_ARGCOUNT;
1756	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1757	if (diag)
1758		return diag;
1759
1760	if (nextarg != argc + 1)
1761		return KDB_ARGCOUNT;
1762
1763	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1764	diag = kdb_putword(addr, contents, width);
1765	if (diag)
1766		return diag;
1767
1768	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1769
1770	return 0;
1771}
1772
1773/*
1774 * kdb_go - This function implements the 'go' command.
1775 *	go [address-expression]
1776 */
1777static int kdb_go(int argc, const char **argv)
1778{
1779	unsigned long addr;
1780	int diag;
1781	int nextarg;
1782	long offset;
1783
1784	if (raw_smp_processor_id() != kdb_initial_cpu) {
1785		kdb_printf("go must execute on the entry cpu, "
1786			   "please use \"cpu %d\" and then execute go\n",
1787			   kdb_initial_cpu);
1788		return KDB_BADCPUNUM;
1789	}
1790	if (argc == 1) {
1791		nextarg = 1;
1792		diag = kdbgetaddrarg(argc, argv, &nextarg,
1793				     &addr, &offset, NULL);
1794		if (diag)
1795			return diag;
1796	} else if (argc) {
1797		return KDB_ARGCOUNT;
1798	}
1799
1800	diag = KDB_CMD_GO;
1801	if (KDB_FLAG(CATASTROPHIC)) {
1802		kdb_printf("Catastrophic error detected\n");
1803		kdb_printf("kdb_continue_catastrophic=%d, ",
1804			kdb_continue_catastrophic);
1805		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1806			kdb_printf("type go a second time if you really want "
1807				   "to continue\n");
1808			return 0;
1809		}
1810		if (kdb_continue_catastrophic == 2) {
1811			kdb_printf("forcing reboot\n");
1812			kdb_reboot(0, NULL);
1813		}
1814		kdb_printf("attempting to continue\n");
1815	}
1816	return diag;
1817}
1818
1819/*
1820 * kdb_rd - This function implements the 'rd' command.
1821 */
1822static int kdb_rd(int argc, const char **argv)
1823{
1824	int len = kdb_check_regs();
1825#if DBG_MAX_REG_NUM > 0
1826	int i;
1827	char *rname;
1828	int rsize;
1829	u64 reg64;
1830	u32 reg32;
1831	u16 reg16;
1832	u8 reg8;
1833
1834	if (len)
1835		return len;
1836
1837	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1838		rsize = dbg_reg_def[i].size * 2;
1839		if (rsize > 16)
1840			rsize = 2;
1841		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1842			len = 0;
1843			kdb_printf("\n");
1844		}
1845		if (len)
1846			len += kdb_printf("  ");
1847		switch(dbg_reg_def[i].size * 8) {
1848		case 8:
1849			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1850			if (!rname)
1851				break;
1852			len += kdb_printf("%s: %02x", rname, reg8);
1853			break;
1854		case 16:
1855			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1856			if (!rname)
1857				break;
1858			len += kdb_printf("%s: %04x", rname, reg16);
1859			break;
1860		case 32:
1861			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1862			if (!rname)
1863				break;
1864			len += kdb_printf("%s: %08x", rname, reg32);
1865			break;
1866		case 64:
1867			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1868			if (!rname)
1869				break;
1870			len += kdb_printf("%s: %016llx", rname, reg64);
1871			break;
1872		default:
1873			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1874		}
1875	}
1876	kdb_printf("\n");
1877#else
1878	if (len)
1879		return len;
1880
1881	kdb_dumpregs(kdb_current_regs);
1882#endif
1883	return 0;
1884}
1885
1886/*
1887 * kdb_rm - This function implements the 'rm' (register modify)  command.
1888 *	rm register-name new-contents
1889 * Remarks:
1890 *	Allows register modification with the same restrictions as gdb
1891 */
1892static int kdb_rm(int argc, const char **argv)
1893{
1894#if DBG_MAX_REG_NUM > 0
1895	int diag;
1896	const char *rname;
1897	int i;
1898	u64 reg64;
1899	u32 reg32;
1900	u16 reg16;
1901	u8 reg8;
1902
1903	if (argc != 2)
1904		return KDB_ARGCOUNT;
1905	/*
1906	 * Allow presence or absence of leading '%' symbol.
1907	 */
1908	rname = argv[1];
1909	if (*rname == '%')
1910		rname++;
1911
1912	diag = kdbgetu64arg(argv[2], &reg64);
1913	if (diag)
1914		return diag;
1915
1916	diag = kdb_check_regs();
1917	if (diag)
1918		return diag;
1919
1920	diag = KDB_BADREG;
1921	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1922		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1923			diag = 0;
1924			break;
1925		}
1926	}
1927	if (!diag) {
1928		switch(dbg_reg_def[i].size * 8) {
1929		case 8:
1930			reg8 = reg64;
1931			dbg_set_reg(i, &reg8, kdb_current_regs);
1932			break;
1933		case 16:
1934			reg16 = reg64;
1935			dbg_set_reg(i, &reg16, kdb_current_regs);
1936			break;
1937		case 32:
1938			reg32 = reg64;
1939			dbg_set_reg(i, &reg32, kdb_current_regs);
1940			break;
1941		case 64:
1942			dbg_set_reg(i, &reg64, kdb_current_regs);
1943			break;
1944		}
1945	}
1946	return diag;
1947#else
1948	kdb_printf("ERROR: Register set currently not implemented\n");
1949    return 0;
1950#endif
1951}
1952
1953#if defined(CONFIG_MAGIC_SYSRQ)
1954/*
1955 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1956 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1957 *		sr <magic-sysrq-code>
1958 */
1959static int kdb_sr(int argc, const char **argv)
1960{
1961	bool check_mask =
1962	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1963
1964	if (argc != 1)
1965		return KDB_ARGCOUNT;
1966
1967	kdb_trap_printk++;
1968	__handle_sysrq(*argv[1], check_mask);
1969	kdb_trap_printk--;
1970
1971	return 0;
1972}
1973#endif	/* CONFIG_MAGIC_SYSRQ */
1974
1975/*
1976 * kdb_ef - This function implements the 'regs' (display exception
1977 *	frame) command.  This command takes an address and expects to
1978 *	find an exception frame at that address, formats and prints
1979 *	it.
1980 *		regs address-expression
1981 * Remarks:
1982 *	Not done yet.
1983 */
1984static int kdb_ef(int argc, const char **argv)
1985{
1986	int diag;
1987	unsigned long addr;
1988	long offset;
1989	int nextarg;
1990
1991	if (argc != 1)
1992		return KDB_ARGCOUNT;
1993
1994	nextarg = 1;
1995	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1996	if (diag)
1997		return diag;
1998	show_regs((struct pt_regs *)addr);
1999	return 0;
2000}
2001
2002#if defined(CONFIG_MODULES)
2003/*
2004 * kdb_lsmod - This function implements the 'lsmod' command.  Lists
2005 *	currently loaded kernel modules.
2006 *	Mostly taken from userland lsmod.
2007 */
2008static int kdb_lsmod(int argc, const char **argv)
2009{
2010	struct module *mod;
2011
2012	if (argc != 0)
2013		return KDB_ARGCOUNT;
2014
2015	kdb_printf("Module                  Size  modstruct     Used by\n");
2016	list_for_each_entry(mod, kdb_modules, list) {
2017		if (mod->state == MODULE_STATE_UNFORMED)
2018			continue;
2019
2020		kdb_printf("%-20s%8u  0x%px ", mod->name,
2021			   mod->core_layout.size, (void *)mod);
2022#ifdef CONFIG_MODULE_UNLOAD
2023		kdb_printf("%4d ", module_refcount(mod));
2024#endif
2025		if (mod->state == MODULE_STATE_GOING)
2026			kdb_printf(" (Unloading)");
2027		else if (mod->state == MODULE_STATE_COMING)
2028			kdb_printf(" (Loading)");
2029		else
2030			kdb_printf(" (Live)");
2031		kdb_printf(" 0x%px", mod->core_layout.base);
2032
2033#ifdef CONFIG_MODULE_UNLOAD
2034		{
2035			struct module_use *use;
2036			kdb_printf(" [ ");
2037			list_for_each_entry(use, &mod->source_list,
2038					    source_list)
2039				kdb_printf("%s ", use->target->name);
2040			kdb_printf("]\n");
2041		}
2042#endif
2043	}
2044
2045	return 0;
2046}
2047
2048#endif	/* CONFIG_MODULES */
2049
2050/*
2051 * kdb_env - This function implements the 'env' command.  Display the
2052 *	current environment variables.
2053 */
2054
2055static int kdb_env(int argc, const char **argv)
2056{
2057	kdb_printenv();
2058
2059	if (KDB_DEBUG(MASK))
2060		kdb_printf("KDBDEBUG=0x%x\n",
2061			(kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2062
2063	return 0;
2064}
2065
2066#ifdef CONFIG_PRINTK
2067/*
2068 * kdb_dmesg - This function implements the 'dmesg' command to display
2069 *	the contents of the syslog buffer.
2070 *		dmesg [lines] [adjust]
2071 */
2072static int kdb_dmesg(int argc, const char **argv)
2073{
2074	int diag;
2075	int logging;
2076	int lines = 0;
2077	int adjust = 0;
2078	int n = 0;
2079	int skip = 0;
2080	struct kmsg_dump_iter iter;
2081	size_t len;
2082	char buf[201];
2083
2084	if (argc > 2)
2085		return KDB_ARGCOUNT;
2086	if (argc) {
2087		char *cp;
2088		lines = simple_strtol(argv[1], &cp, 0);
2089		if (*cp)
2090			lines = 0;
2091		if (argc > 1) {
2092			adjust = simple_strtoul(argv[2], &cp, 0);
2093			if (*cp || adjust < 0)
2094				adjust = 0;
2095		}
2096	}
2097
2098	/* disable LOGGING if set */
2099	diag = kdbgetintenv("LOGGING", &logging);
2100	if (!diag && logging) {
2101		const char *setargs[] = { "set", "LOGGING", "0" };
2102		kdb_set(2, setargs);
2103	}
2104
2105	kmsg_dump_rewind(&iter);
2106	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2107		n++;
2108
2109	if (lines < 0) {
2110		if (adjust >= n)
2111			kdb_printf("buffer only contains %d lines, nothing "
2112				   "printed\n", n);
2113		else if (adjust - lines >= n)
2114			kdb_printf("buffer only contains %d lines, last %d "
2115				   "lines printed\n", n, n - adjust);
2116		skip = adjust;
2117		lines = abs(lines);
2118	} else if (lines > 0) {
2119		skip = n - lines - adjust;
2120		lines = abs(lines);
2121		if (adjust >= n) {
2122			kdb_printf("buffer only contains %d lines, "
2123				   "nothing printed\n", n);
2124			skip = n;
2125		} else if (skip < 0) {
2126			lines += skip;
2127			skip = 0;
2128			kdb_printf("buffer only contains %d lines, first "
2129				   "%d lines printed\n", n, lines);
2130		}
2131	} else {
2132		lines = n;
2133	}
2134
2135	if (skip >= n || skip < 0)
2136		return 0;
2137
2138	kmsg_dump_rewind(&iter);
2139	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2140		if (skip) {
2141			skip--;
2142			continue;
2143		}
2144		if (!lines--)
2145			break;
2146		if (KDB_FLAG(CMD_INTERRUPT))
2147			return 0;
2148
2149		kdb_printf("%.*s\n", (int)len - 1, buf);
2150	}
2151
2152	return 0;
2153}
2154#endif /* CONFIG_PRINTK */
2155
2156/* Make sure we balance enable/disable calls, must disable first. */
2157static atomic_t kdb_nmi_disabled;
2158
2159static int kdb_disable_nmi(int argc, const char *argv[])
2160{
2161	if (atomic_read(&kdb_nmi_disabled))
2162		return 0;
2163	atomic_set(&kdb_nmi_disabled, 1);
2164	arch_kgdb_ops.enable_nmi(0);
2165	return 0;
2166}
2167
2168static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2169{
2170	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2171		return -EINVAL;
2172	arch_kgdb_ops.enable_nmi(1);
2173	return 0;
2174}
2175
2176static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2177	.set = kdb_param_enable_nmi,
2178};
2179module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2180
2181/*
2182 * kdb_cpu - This function implements the 'cpu' command.
2183 *	cpu	[<cpunum>]
2184 * Returns:
2185 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2186 */
2187static void kdb_cpu_status(void)
2188{
2189	int i, start_cpu, first_print = 1;
2190	char state, prev_state = '?';
2191
2192	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2193	kdb_printf("Available cpus: ");
2194	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2195		if (!cpu_online(i)) {
2196			state = 'F';	/* cpu is offline */
2197		} else if (!kgdb_info[i].enter_kgdb) {
2198			state = 'D';	/* cpu is online but unresponsive */
2199		} else {
2200			state = ' ';	/* cpu is responding to kdb */
2201			if (kdb_task_state_char(KDB_TSK(i)) == 'I')
2202				state = 'I';	/* idle task */
2203		}
2204		if (state != prev_state) {
2205			if (prev_state != '?') {
2206				if (!first_print)
2207					kdb_printf(", ");
2208				first_print = 0;
2209				kdb_printf("%d", start_cpu);
2210				if (start_cpu < i-1)
2211					kdb_printf("-%d", i-1);
2212				if (prev_state != ' ')
2213					kdb_printf("(%c)", prev_state);
2214			}
2215			prev_state = state;
2216			start_cpu = i;
2217		}
2218	}
2219	/* print the trailing cpus, ignoring them if they are all offline */
2220	if (prev_state != 'F') {
2221		if (!first_print)
2222			kdb_printf(", ");
2223		kdb_printf("%d", start_cpu);
2224		if (start_cpu < i-1)
2225			kdb_printf("-%d", i-1);
2226		if (prev_state != ' ')
2227			kdb_printf("(%c)", prev_state);
2228	}
2229	kdb_printf("\n");
2230}
2231
2232static int kdb_cpu(int argc, const char **argv)
2233{
2234	unsigned long cpunum;
2235	int diag;
2236
2237	if (argc == 0) {
2238		kdb_cpu_status();
2239		return 0;
2240	}
2241
2242	if (argc != 1)
2243		return KDB_ARGCOUNT;
2244
2245	diag = kdbgetularg(argv[1], &cpunum);
2246	if (diag)
2247		return diag;
2248
2249	/*
2250	 * Validate cpunum
2251	 */
2252	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2253		return KDB_BADCPUNUM;
2254
2255	dbg_switch_cpu = cpunum;
2256
2257	/*
2258	 * Switch to other cpu
2259	 */
2260	return KDB_CMD_CPU;
2261}
2262
2263/* The user may not realize that ps/bta with no parameters does not print idle
2264 * or sleeping system daemon processes, so tell them how many were suppressed.
2265 */
2266void kdb_ps_suppressed(void)
2267{
2268	int idle = 0, daemon = 0;
2269	unsigned long mask_I = kdb_task_state_string("I"),
2270		      mask_M = kdb_task_state_string("M");
2271	unsigned long cpu;
2272	const struct task_struct *p, *g;
2273	for_each_online_cpu(cpu) {
2274		p = kdb_curr_task(cpu);
2275		if (kdb_task_state(p, mask_I))
2276			++idle;
2277	}
2278	for_each_process_thread(g, p) {
2279		if (kdb_task_state(p, mask_M))
2280			++daemon;
2281	}
2282	if (idle || daemon) {
2283		if (idle)
2284			kdb_printf("%d idle process%s (state I)%s\n",
2285				   idle, idle == 1 ? "" : "es",
2286				   daemon ? " and " : "");
2287		if (daemon)
2288			kdb_printf("%d sleeping system daemon (state M) "
2289				   "process%s", daemon,
2290				   daemon == 1 ? "" : "es");
2291		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2292	}
2293}
2294
2295/*
2296 * kdb_ps - This function implements the 'ps' command which shows a
2297 *	list of the active processes.
2298 *		ps [DRSTCZEUIMA]   All processes, optionally filtered by state
2299 */
2300void kdb_ps1(const struct task_struct *p)
2301{
2302	int cpu;
2303	unsigned long tmp;
2304
2305	if (!p ||
2306	    copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2307		return;
2308
2309	cpu = kdb_process_cpu(p);
2310	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2311		   (void *)p, p->pid, p->parent->pid,
2312		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2313		   kdb_task_state_char(p),
2314		   (void *)(&p->thread),
2315		   p == kdb_curr_task(raw_smp_processor_id()) ? '*' : ' ',
2316		   p->comm);
2317	if (kdb_task_has_cpu(p)) {
2318		if (!KDB_TSK(cpu)) {
2319			kdb_printf("  Error: no saved data for this cpu\n");
2320		} else {
2321			if (KDB_TSK(cpu) != p)
2322				kdb_printf("  Error: does not match running "
2323				   "process table (0x%px)\n", KDB_TSK(cpu));
2324		}
2325	}
2326}
2327
 
 
 
 
 
 
 
2328static int kdb_ps(int argc, const char **argv)
2329{
2330	struct task_struct *g, *p;
2331	unsigned long mask, cpu;
 
2332
2333	if (argc == 0)
2334		kdb_ps_suppressed();
2335	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2336		(int)(2*sizeof(void *))+2, "Task Addr",
2337		(int)(2*sizeof(void *))+2, "Thread");
2338	mask = kdb_task_state_string(argc ? argv[1] : NULL);
2339	/* Run the active tasks first */
2340	for_each_online_cpu(cpu) {
2341		if (KDB_FLAG(CMD_INTERRUPT))
2342			return 0;
2343		p = kdb_curr_task(cpu);
2344		if (kdb_task_state(p, mask))
2345			kdb_ps1(p);
2346	}
2347	kdb_printf("\n");
2348	/* Now the real tasks */
2349	for_each_process_thread(g, p) {
2350		if (KDB_FLAG(CMD_INTERRUPT))
2351			return 0;
2352		if (kdb_task_state(p, mask))
2353			kdb_ps1(p);
2354	}
2355
2356	return 0;
2357}
2358
2359/*
2360 * kdb_pid - This function implements the 'pid' command which switches
2361 *	the currently active process.
2362 *		pid [<pid> | R]
2363 */
2364static int kdb_pid(int argc, const char **argv)
2365{
2366	struct task_struct *p;
2367	unsigned long val;
2368	int diag;
2369
2370	if (argc > 1)
2371		return KDB_ARGCOUNT;
2372
2373	if (argc) {
2374		if (strcmp(argv[1], "R") == 0) {
2375			p = KDB_TSK(kdb_initial_cpu);
2376		} else {
2377			diag = kdbgetularg(argv[1], &val);
2378			if (diag)
2379				return KDB_BADINT;
2380
2381			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2382			if (!p) {
2383				kdb_printf("No task with pid=%d\n", (pid_t)val);
2384				return 0;
2385			}
2386		}
2387		kdb_set_current_task(p);
2388	}
2389	kdb_printf("KDB current process is %s(pid=%d)\n",
2390		   kdb_current_task->comm,
2391		   kdb_current_task->pid);
2392
2393	return 0;
2394}
2395
2396static int kdb_kgdb(int argc, const char **argv)
2397{
2398	return KDB_CMD_KGDB;
2399}
2400
2401/*
2402 * kdb_help - This function implements the 'help' and '?' commands.
2403 */
2404static int kdb_help(int argc, const char **argv)
2405{
2406	kdbtab_t *kt;
2407
2408	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2409	kdb_printf("-----------------------------"
2410		   "-----------------------------\n");
2411	list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2412		char *space = "";
2413		if (KDB_FLAG(CMD_INTERRUPT))
2414			return 0;
2415		if (!kdb_check_flags(kt->cmd_flags, kdb_cmd_enabled, true))
2416			continue;
2417		if (strlen(kt->cmd_usage) > 20)
2418			space = "\n                                    ";
2419		kdb_printf("%-15.15s %-20s%s%s\n", kt->cmd_name,
2420			   kt->cmd_usage, space, kt->cmd_help);
2421	}
2422	return 0;
2423}
2424
2425/*
2426 * kdb_kill - This function implements the 'kill' commands.
2427 */
2428static int kdb_kill(int argc, const char **argv)
2429{
2430	long sig, pid;
2431	char *endp;
2432	struct task_struct *p;
2433
2434	if (argc != 2)
2435		return KDB_ARGCOUNT;
2436
2437	sig = simple_strtol(argv[1], &endp, 0);
2438	if (*endp)
2439		return KDB_BADINT;
2440	if ((sig >= 0) || !valid_signal(-sig)) {
2441		kdb_printf("Invalid signal parameter.<-signal>\n");
2442		return 0;
2443	}
2444	sig = -sig;
2445
2446	pid = simple_strtol(argv[2], &endp, 0);
2447	if (*endp)
2448		return KDB_BADINT;
2449	if (pid <= 0) {
2450		kdb_printf("Process ID must be large than 0.\n");
2451		return 0;
2452	}
2453
2454	/* Find the process. */
2455	p = find_task_by_pid_ns(pid, &init_pid_ns);
2456	if (!p) {
2457		kdb_printf("The specified process isn't found.\n");
2458		return 0;
2459	}
2460	p = p->group_leader;
2461	kdb_send_sig(p, sig);
2462	return 0;
2463}
2464
2465/*
2466 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2467 * I cannot call that code directly from kdb, it has an unconditional
2468 * cli()/sti() and calls routines that take locks which can stop the debugger.
2469 */
2470static void kdb_sysinfo(struct sysinfo *val)
2471{
2472	u64 uptime = ktime_get_mono_fast_ns();
2473
2474	memset(val, 0, sizeof(*val));
2475	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2476	val->loads[0] = avenrun[0];
2477	val->loads[1] = avenrun[1];
2478	val->loads[2] = avenrun[2];
2479	val->procs = nr_threads-1;
2480	si_meminfo(val);
2481
2482	return;
2483}
2484
2485/*
2486 * kdb_summary - This function implements the 'summary' command.
2487 */
2488static int kdb_summary(int argc, const char **argv)
2489{
2490	time64_t now;
2491	struct sysinfo val;
2492
2493	if (argc)
2494		return KDB_ARGCOUNT;
2495
2496	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2497	kdb_printf("release    %s\n", init_uts_ns.name.release);
2498	kdb_printf("version    %s\n", init_uts_ns.name.version);
2499	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2500	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2501	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2502
2503	now = __ktime_get_real_seconds();
2504	kdb_printf("date       %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
2505	kdb_sysinfo(&val);
2506	kdb_printf("uptime     ");
2507	if (val.uptime > (24*60*60)) {
2508		int days = val.uptime / (24*60*60);
2509		val.uptime %= (24*60*60);
2510		kdb_printf("%d day%s ", days, days == 1 ? "" : "s");
2511	}
2512	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2513
2514	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2515		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2516		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2517		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2518
2519	/* Display in kilobytes */
2520#define K(x) ((x) << (PAGE_SHIFT - 10))
2521	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2522		   "Buffers:        %8lu kB\n",
2523		   K(val.totalram), K(val.freeram), K(val.bufferram));
2524	return 0;
2525}
2526
2527/*
2528 * kdb_per_cpu - This function implements the 'per_cpu' command.
2529 */
2530static int kdb_per_cpu(int argc, const char **argv)
2531{
2532	char fmtstr[64];
2533	int cpu, diag, nextarg = 1;
2534	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2535
2536	if (argc < 1 || argc > 3)
2537		return KDB_ARGCOUNT;
2538
2539	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2540	if (diag)
2541		return diag;
2542
2543	if (argc >= 2) {
2544		diag = kdbgetularg(argv[2], &bytesperword);
2545		if (diag)
2546			return diag;
2547	}
2548	if (!bytesperword)
2549		bytesperword = KDB_WORD_SIZE;
2550	else if (bytesperword > KDB_WORD_SIZE)
2551		return KDB_BADWIDTH;
2552	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2553	if (argc >= 3) {
2554		diag = kdbgetularg(argv[3], &whichcpu);
2555		if (diag)
2556			return diag;
2557		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2558			kdb_printf("cpu %ld is not online\n", whichcpu);
2559			return KDB_BADCPUNUM;
2560		}
2561	}
2562
2563	/* Most architectures use __per_cpu_offset[cpu], some use
2564	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2565	 */
2566#ifdef	__per_cpu_offset
2567#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2568#else
2569#ifdef	CONFIG_SMP
2570#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2571#else
2572#define KDB_PCU(cpu) 0
2573#endif
2574#endif
2575	for_each_online_cpu(cpu) {
2576		if (KDB_FLAG(CMD_INTERRUPT))
2577			return 0;
2578
2579		if (whichcpu != ~0UL && whichcpu != cpu)
2580			continue;
2581		addr = symaddr + KDB_PCU(cpu);
2582		diag = kdb_getword(&val, addr, bytesperword);
2583		if (diag) {
2584			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2585				   "read, diag=%d\n", cpu, addr, diag);
2586			continue;
2587		}
2588		kdb_printf("%5d ", cpu);
2589		kdb_md_line(fmtstr, addr,
2590			bytesperword == KDB_WORD_SIZE,
2591			1, bytesperword, 1, 1, 0);
2592	}
2593#undef KDB_PCU
2594	return 0;
2595}
2596
2597/*
2598 * display help for the use of cmd | grep pattern
2599 */
2600static int kdb_grep_help(int argc, const char **argv)
2601{
2602	kdb_printf("Usage of  cmd args | grep pattern:\n");
2603	kdb_printf("  Any command's output may be filtered through an ");
2604	kdb_printf("emulated 'pipe'.\n");
2605	kdb_printf("  'grep' is just a key word.\n");
2606	kdb_printf("  The pattern may include a very limited set of "
2607		   "metacharacters:\n");
2608	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2609	kdb_printf("  And if there are spaces in the pattern, you may "
2610		   "quote it:\n");
2611	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2612		   " or \"^pat tern$\"\n");
2613	return 0;
2614}
2615
2616/*
2617 * kdb_register_flags - This function is used to register a kernel
2618 * 	debugger command.
2619 * Inputs:
2620 *	cmd	Command name
2621 *	func	Function to execute the command
2622 *	usage	A simple usage string showing arguments
2623 *	help	A simple help string describing command
2624 *	repeat	Does the command auto repeat on enter?
2625 * Returns:
2626 *	zero for success, one if a duplicate command.
2627 */
2628int kdb_register_flags(char *cmd,
2629		       kdb_func_t func,
2630		       char *usage,
2631		       char *help,
2632		       short minlen,
2633		       kdb_cmdflags_t flags)
2634{
2635	kdbtab_t *kp;
2636
2637	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2638		if (strcmp(kp->cmd_name, cmd) == 0) {
2639			kdb_printf("Duplicate kdb command registered: "
2640				"%s, func %px help %s\n", cmd, func, help);
2641			return 1;
2642		}
2643	}
2644
2645	kp = kmalloc(sizeof(*kp), GFP_KDB);
2646	if (!kp) {
2647		kdb_printf("Could not allocate new kdb_command table\n");
2648		return 1;
2649	}
2650
2651	kp->cmd_name   = cmd;
2652	kp->cmd_func   = func;
2653	kp->cmd_usage  = usage;
2654	kp->cmd_help   = help;
2655	kp->cmd_minlen = minlen;
2656	kp->cmd_flags  = flags;
2657	kp->is_dynamic = true;
2658
2659	list_add_tail(&kp->list_node, &kdb_cmds_head);
2660
2661	return 0;
2662}
2663EXPORT_SYMBOL_GPL(kdb_register_flags);
2664
2665/*
2666 * kdb_register_table() - This function is used to register a kdb command
2667 *                        table.
2668 * @kp: pointer to kdb command table
2669 * @len: length of kdb command table
2670 */
2671void kdb_register_table(kdbtab_t *kp, size_t len)
2672{
2673	while (len--) {
2674		list_add_tail(&kp->list_node, &kdb_cmds_head);
2675		kp++;
2676	}
2677}
2678
2679/*
2680 * kdb_register - Compatibility register function for commands that do
2681 *	not need to specify a repeat state.  Equivalent to
2682 *	kdb_register_flags with flags set to 0.
2683 * Inputs:
2684 *	cmd	Command name
2685 *	func	Function to execute the command
2686 *	usage	A simple usage string showing arguments
2687 *	help	A simple help string describing command
2688 * Returns:
2689 *	zero for success, one if a duplicate command.
2690 */
2691int kdb_register(char *cmd,
2692	     kdb_func_t func,
2693	     char *usage,
2694	     char *help,
2695	     short minlen)
2696{
2697	return kdb_register_flags(cmd, func, usage, help, minlen, 0);
2698}
2699EXPORT_SYMBOL_GPL(kdb_register);
2700
2701/*
2702 * kdb_unregister - This function is used to unregister a kernel
2703 *	debugger command.  It is generally called when a module which
2704 *	implements kdb commands is unloaded.
2705 * Inputs:
2706 *	cmd	Command name
2707 * Returns:
2708 *	zero for success, one command not registered.
2709 */
2710int kdb_unregister(char *cmd)
2711{
2712	kdbtab_t *kp;
2713
2714	/*
2715	 *  find the command.
2716	 */
2717	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2718		if (strcmp(kp->cmd_name, cmd) == 0) {
2719			list_del(&kp->list_node);
2720			if (kp->is_dynamic)
2721				kfree(kp);
2722			return 0;
2723		}
2724	}
2725
2726	/* Couldn't find it.  */
2727	return 1;
2728}
2729EXPORT_SYMBOL_GPL(kdb_unregister);
2730
2731static kdbtab_t maintab[] = {
2732	{	.cmd_name = "md",
2733		.cmd_func = kdb_md,
2734		.cmd_usage = "<vaddr>",
2735		.cmd_help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2736		.cmd_minlen = 1,
2737		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2738	},
2739	{	.cmd_name = "mdr",
2740		.cmd_func = kdb_md,
2741		.cmd_usage = "<vaddr> <bytes>",
2742		.cmd_help = "Display Raw Memory",
2743		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2744	},
2745	{	.cmd_name = "mdp",
2746		.cmd_func = kdb_md,
2747		.cmd_usage = "<paddr> <bytes>",
2748		.cmd_help = "Display Physical Memory",
2749		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2750	},
2751	{	.cmd_name = "mds",
2752		.cmd_func = kdb_md,
2753		.cmd_usage = "<vaddr>",
2754		.cmd_help = "Display Memory Symbolically",
2755		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2756	},
2757	{	.cmd_name = "mm",
2758		.cmd_func = kdb_mm,
2759		.cmd_usage = "<vaddr> <contents>",
2760		.cmd_help = "Modify Memory Contents",
2761		.cmd_flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2762	},
2763	{	.cmd_name = "go",
2764		.cmd_func = kdb_go,
2765		.cmd_usage = "[<vaddr>]",
2766		.cmd_help = "Continue Execution",
2767		.cmd_minlen = 1,
2768		.cmd_flags = KDB_ENABLE_REG_WRITE |
2769			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2770	},
2771	{	.cmd_name = "rd",
2772		.cmd_func = kdb_rd,
2773		.cmd_usage = "",
2774		.cmd_help = "Display Registers",
2775		.cmd_flags = KDB_ENABLE_REG_READ,
2776	},
2777	{	.cmd_name = "rm",
2778		.cmd_func = kdb_rm,
2779		.cmd_usage = "<reg> <contents>",
2780		.cmd_help = "Modify Registers",
2781		.cmd_flags = KDB_ENABLE_REG_WRITE,
2782	},
2783	{	.cmd_name = "ef",
2784		.cmd_func = kdb_ef,
2785		.cmd_usage = "<vaddr>",
2786		.cmd_help = "Display exception frame",
2787		.cmd_flags = KDB_ENABLE_MEM_READ,
2788	},
2789	{	.cmd_name = "bt",
2790		.cmd_func = kdb_bt,
2791		.cmd_usage = "[<vaddr>]",
2792		.cmd_help = "Stack traceback",
2793		.cmd_minlen = 1,
2794		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2795	},
2796	{	.cmd_name = "btp",
2797		.cmd_func = kdb_bt,
2798		.cmd_usage = "<pid>",
2799		.cmd_help = "Display stack for process <pid>",
2800		.cmd_flags = KDB_ENABLE_INSPECT,
2801	},
2802	{	.cmd_name = "bta",
2803		.cmd_func = kdb_bt,
2804		.cmd_usage = "[D|R|S|T|C|Z|E|U|I|M|A]",
2805		.cmd_help = "Backtrace all processes matching state flag",
2806		.cmd_flags = KDB_ENABLE_INSPECT,
2807	},
2808	{	.cmd_name = "btc",
2809		.cmd_func = kdb_bt,
2810		.cmd_usage = "",
2811		.cmd_help = "Backtrace current process on each cpu",
2812		.cmd_flags = KDB_ENABLE_INSPECT,
2813	},
2814	{	.cmd_name = "btt",
2815		.cmd_func = kdb_bt,
2816		.cmd_usage = "<vaddr>",
2817		.cmd_help = "Backtrace process given its struct task address",
2818		.cmd_flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2819	},
2820	{	.cmd_name = "env",
2821		.cmd_func = kdb_env,
2822		.cmd_usage = "",
2823		.cmd_help = "Show environment variables",
2824		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2825	},
2826	{	.cmd_name = "set",
2827		.cmd_func = kdb_set,
2828		.cmd_usage = "",
2829		.cmd_help = "Set environment variables",
2830		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2831	},
2832	{	.cmd_name = "help",
2833		.cmd_func = kdb_help,
2834		.cmd_usage = "",
2835		.cmd_help = "Display Help Message",
2836		.cmd_minlen = 1,
2837		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2838	},
2839	{	.cmd_name = "?",
2840		.cmd_func = kdb_help,
2841		.cmd_usage = "",
2842		.cmd_help = "Display Help Message",
2843		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2844	},
2845	{	.cmd_name = "cpu",
2846		.cmd_func = kdb_cpu,
2847		.cmd_usage = "<cpunum>",
2848		.cmd_help = "Switch to new cpu",
2849		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2850	},
2851	{	.cmd_name = "kgdb",
2852		.cmd_func = kdb_kgdb,
2853		.cmd_usage = "",
2854		.cmd_help = "Enter kgdb mode",
2855		.cmd_flags = 0,
2856	},
2857	{	.cmd_name = "ps",
2858		.cmd_func = kdb_ps,
2859		.cmd_usage = "[<flags>|A]",
2860		.cmd_help = "Display active task list",
2861		.cmd_flags = KDB_ENABLE_INSPECT,
2862	},
2863	{	.cmd_name = "pid",
2864		.cmd_func = kdb_pid,
2865		.cmd_usage = "<pidnum>",
2866		.cmd_help = "Switch to another task",
2867		.cmd_flags = KDB_ENABLE_INSPECT,
2868	},
2869	{	.cmd_name = "reboot",
2870		.cmd_func = kdb_reboot,
2871		.cmd_usage = "",
2872		.cmd_help = "Reboot the machine immediately",
2873		.cmd_flags = KDB_ENABLE_REBOOT,
2874	},
2875#if defined(CONFIG_MODULES)
2876	{	.cmd_name = "lsmod",
2877		.cmd_func = kdb_lsmod,
2878		.cmd_usage = "",
2879		.cmd_help = "List loaded kernel modules",
2880		.cmd_flags = KDB_ENABLE_INSPECT,
2881	},
2882#endif
2883#if defined(CONFIG_MAGIC_SYSRQ)
2884	{	.cmd_name = "sr",
2885		.cmd_func = kdb_sr,
2886		.cmd_usage = "<key>",
2887		.cmd_help = "Magic SysRq key",
2888		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2889	},
2890#endif
2891#if defined(CONFIG_PRINTK)
2892	{	.cmd_name = "dmesg",
2893		.cmd_func = kdb_dmesg,
2894		.cmd_usage = "[lines]",
2895		.cmd_help = "Display syslog buffer",
2896		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2897	},
2898#endif
2899	{	.cmd_name = "defcmd",
2900		.cmd_func = kdb_defcmd,
2901		.cmd_usage = "name \"usage\" \"help\"",
2902		.cmd_help = "Define a set of commands, down to endefcmd",
2903		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2904	},
2905	{	.cmd_name = "kill",
2906		.cmd_func = kdb_kill,
2907		.cmd_usage = "<-signal> <pid>",
2908		.cmd_help = "Send a signal to a process",
2909		.cmd_flags = KDB_ENABLE_SIGNAL,
2910	},
2911	{	.cmd_name = "summary",
2912		.cmd_func = kdb_summary,
2913		.cmd_usage = "",
2914		.cmd_help = "Summarize the system",
2915		.cmd_minlen = 4,
2916		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2917	},
2918	{	.cmd_name = "per_cpu",
2919		.cmd_func = kdb_per_cpu,
2920		.cmd_usage = "<sym> [<bytes>] [<cpu>]",
2921		.cmd_help = "Display per_cpu variables",
2922		.cmd_minlen = 3,
2923		.cmd_flags = KDB_ENABLE_MEM_READ,
2924	},
2925	{	.cmd_name = "grephelp",
2926		.cmd_func = kdb_grep_help,
2927		.cmd_usage = "",
2928		.cmd_help = "Display help on | grep",
2929		.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
 
 
 
 
 
2930	},
2931};
2932
2933static kdbtab_t nmicmd = {
2934	.cmd_name = "disable_nmi",
2935	.cmd_func = kdb_disable_nmi,
2936	.cmd_usage = "",
2937	.cmd_help = "Disable NMI entry to KDB",
2938	.cmd_flags = KDB_ENABLE_ALWAYS_SAFE,
2939};
2940
2941/* Initialize the kdb command table. */
2942static void __init kdb_inittab(void)
2943{
2944	kdb_register_table(maintab, ARRAY_SIZE(maintab));
2945	if (arch_kgdb_ops.enable_nmi)
2946		kdb_register_table(&nmicmd, 1);
2947}
2948
2949/* Execute any commands defined in kdb_cmds.  */
2950static void __init kdb_cmd_init(void)
2951{
2952	int i, diag;
2953	for (i = 0; kdb_cmds[i]; ++i) {
2954		diag = kdb_parse(kdb_cmds[i]);
2955		if (diag)
2956			kdb_printf("kdb command %s failed, kdb diag %d\n",
2957				kdb_cmds[i], diag);
2958	}
2959	if (defcmd_in_progress) {
2960		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2961		kdb_parse("endefcmd");
2962	}
2963}
2964
2965/* Initialize kdb_printf, breakpoint tables and kdb state */
2966void __init kdb_init(int lvl)
2967{
2968	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2969	int i;
2970
2971	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2972		return;
2973	for (i = kdb_init_lvl; i < lvl; i++) {
2974		switch (i) {
2975		case KDB_NOT_INITIALIZED:
2976			kdb_inittab();		/* Initialize Command Table */
2977			kdb_initbptab();	/* Initialize Breakpoints */
2978			break;
2979		case KDB_INIT_EARLY:
2980			kdb_cmd_init();		/* Build kdb_cmds tables */
2981			break;
2982		}
2983	}
2984	kdb_init_lvl = lvl;
2985}
v6.13.7
   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
 158/*
 159 * Update the permissions flags (kdb_cmd_enabled) to match the
 160 * current lockdown state.
 161 *
 162 * Within this function the calls to security_locked_down() are "lazy". We
 163 * avoid calling them if the current value of kdb_cmd_enabled already excludes
 164 * flags that might be subject to lockdown. Additionally we deliberately check
 165 * the lockdown flags independently (even though read lockdown implies write
 166 * lockdown) since that results in both simpler code and clearer messages to
 167 * the user on first-time debugger entry.
 168 *
 169 * The permission masks during a read+write lockdown permits the following
 170 * flags: INSPECT, SIGNAL, REBOOT (and ALWAYS_SAFE).
 171 *
 172 * The INSPECT commands are not blocked during lockdown because they are
 173 * not arbitrary memory reads. INSPECT covers the backtrace family (sometimes
 174 * forcing them to have no arguments) and lsmod. These commands do expose
 175 * some kernel state but do not allow the developer seated at the console to
 176 * choose what state is reported. SIGNAL and REBOOT should not be controversial,
 177 * given these are allowed for root during lockdown already.
 178 */
 179static void kdb_check_for_lockdown(void)
 180{
 181	const int write_flags = KDB_ENABLE_MEM_WRITE |
 182				KDB_ENABLE_REG_WRITE |
 183				KDB_ENABLE_FLOW_CTRL;
 184	const int read_flags = KDB_ENABLE_MEM_READ |
 185			       KDB_ENABLE_REG_READ;
 186
 187	bool need_to_lockdown_write = false;
 188	bool need_to_lockdown_read = false;
 189
 190	if (kdb_cmd_enabled & (KDB_ENABLE_ALL | write_flags))
 191		need_to_lockdown_write =
 192			security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL);
 193
 194	if (kdb_cmd_enabled & (KDB_ENABLE_ALL | read_flags))
 195		need_to_lockdown_read =
 196			security_locked_down(LOCKDOWN_DBG_READ_KERNEL);
 197
 198	/* De-compose KDB_ENABLE_ALL if required */
 199	if (need_to_lockdown_write || need_to_lockdown_read)
 200		if (kdb_cmd_enabled & KDB_ENABLE_ALL)
 201			kdb_cmd_enabled = KDB_ENABLE_MASK & ~KDB_ENABLE_ALL;
 202
 203	if (need_to_lockdown_write)
 204		kdb_cmd_enabled &= ~write_flags;
 205
 206	if (need_to_lockdown_read)
 207		kdb_cmd_enabled &= ~read_flags;
 208}
 209
 210/*
 211 * Check whether the flags of the current command, the permissions of the kdb
 212 * console and the lockdown state allow a command to be run.
 213 */
 214static bool kdb_check_flags(kdb_cmdflags_t flags, int permissions,
 215				   bool no_args)
 216{
 217	/* permissions comes from userspace so needs massaging slightly */
 218	permissions &= KDB_ENABLE_MASK;
 219	permissions |= KDB_ENABLE_ALWAYS_SAFE;
 220
 221	/* some commands change group when launched with no arguments */
 222	if (no_args)
 223		permissions |= permissions << KDB_ENABLE_NO_ARGS_SHIFT;
 224
 225	flags |= KDB_ENABLE_ALL;
 226
 227	return permissions & flags;
 228}
 229
 230/*
 231 * kdbgetenv - This function will return the character string value of
 232 *	an environment variable.
 233 * Parameters:
 234 *	match	A character string representing an environment variable.
 235 * Returns:
 236 *	NULL	No environment variable matches 'match'
 237 *	char*	Pointer to string value of environment variable.
 238 */
 239char *kdbgetenv(const char *match)
 240{
 241	char **ep = __env;
 242	int matchlen = strlen(match);
 243	int i;
 244
 245	for (i = 0; i < __nenv; i++) {
 246		char *e = *ep++;
 247
 248		if (!e)
 249			continue;
 250
 251		if ((strncmp(match, e, matchlen) == 0)
 252		 && ((e[matchlen] == '\0')
 253		   || (e[matchlen] == '='))) {
 254			char *cp = strchr(e, '=');
 255			return cp ? ++cp : "";
 256		}
 257	}
 258	return NULL;
 259}
 260
 261/*
 262 * kdballocenv - This function is used to allocate bytes for
 263 *	environment entries.
 264 * Parameters:
 265 *	bytes	The number of bytes to allocate in the static buffer.
 
 
 266 * Returns:
 267 *	A pointer to the allocated space in the buffer on success.
 268 *	NULL if bytes > size available in the envbuffer.
 269 * Remarks:
 270 *	We use a static environment buffer (envbuffer) to hold the values
 271 *	of dynamically generated environment variables (see kdb_set).  Buffer
 272 *	space once allocated is never free'd, so over time, the amount of space
 273 *	(currently 512 bytes) will be exhausted if env variables are changed
 274 *	frequently.
 275 */
 276static char *kdballocenv(size_t bytes)
 277{
 278#define	KDB_ENVBUFSIZE	512
 279	static char envbuffer[KDB_ENVBUFSIZE];
 280	static int envbufsize;
 281	char *ep = NULL;
 282
 283	if ((KDB_ENVBUFSIZE - envbufsize) >= bytes) {
 284		ep = &envbuffer[envbufsize];
 285		envbufsize += bytes;
 286	}
 287	return ep;
 288}
 289
 290/*
 291 * kdbgetulenv - This function will return the value of an unsigned
 292 *	long-valued environment variable.
 293 * Parameters:
 294 *	match	A character string representing a numeric value
 295 * Outputs:
 296 *	*value  the unsigned long representation of the env variable 'match'
 297 * Returns:
 298 *	Zero on success, a kdb diagnostic on failure.
 299 */
 300static int kdbgetulenv(const char *match, unsigned long *value)
 301{
 302	char *ep;
 303
 304	ep = kdbgetenv(match);
 305	if (!ep)
 306		return KDB_NOTENV;
 307	if (strlen(ep) == 0)
 308		return KDB_NOENVVALUE;
 309	if (kstrtoul(ep, 0, value))
 310		return KDB_BADINT;
 311
 312	return 0;
 313}
 314
 315/*
 316 * kdbgetintenv - This function will return the value of an
 317 *	integer-valued environment variable.
 318 * Parameters:
 319 *	match	A character string representing an integer-valued env variable
 320 * Outputs:
 321 *	*value  the integer representation of the environment variable 'match'
 322 * Returns:
 323 *	Zero on success, a kdb diagnostic on failure.
 324 */
 325int kdbgetintenv(const char *match, int *value)
 326{
 327	unsigned long val;
 328	int diag;
 329
 330	diag = kdbgetulenv(match, &val);
 331	if (!diag)
 332		*value = (int) val;
 333	return diag;
 334}
 335
 336/*
 337 * kdb_setenv() - Alter an existing environment variable or create a new one.
 338 * @var: Name of the variable
 339 * @val: Value of the variable
 340 *
 341 * Return: Zero on success, a kdb diagnostic on failure.
 342 */
 343static int kdb_setenv(const char *var, const char *val)
 344{
 345	int i;
 346	char *ep;
 347	size_t varlen, vallen;
 348
 349	varlen = strlen(var);
 350	vallen = strlen(val);
 351	ep = kdballocenv(varlen + vallen + 2);
 352	if (ep == (char *)0)
 353		return KDB_ENVBUFFULL;
 354
 355	sprintf(ep, "%s=%s", var, val);
 356
 357	for (i = 0; i < __nenv; i++) {
 358		if (__env[i]
 359		 && ((strncmp(__env[i], var, varlen) == 0)
 360		   && ((__env[i][varlen] == '\0')
 361		    || (__env[i][varlen] == '=')))) {
 362			__env[i] = ep;
 363			return 0;
 364		}
 365	}
 366
 367	/*
 368	 * Wasn't existing variable.  Fit into slot.
 369	 */
 370	for (i = 0; i < __nenv-1; i++) {
 371		if (__env[i] == (char *)0) {
 372			__env[i] = ep;
 373			return 0;
 374		}
 375	}
 376
 377	return KDB_ENVFULL;
 378}
 379
 380/*
 381 * kdb_printenv() - Display the current environment variables.
 382 */
 383static void kdb_printenv(void)
 384{
 385	int i;
 386
 387	for (i = 0; i < __nenv; i++) {
 388		if (__env[i])
 389			kdb_printf("%s\n", __env[i]);
 390	}
 391}
 392
 393/*
 394 * kdbgetularg - This function will convert a numeric string into an
 395 *	unsigned long value.
 396 * Parameters:
 397 *	arg	A character string representing a numeric value
 398 * Outputs:
 399 *	*value  the unsigned long representation of arg.
 400 * Returns:
 401 *	Zero on success, a kdb diagnostic on failure.
 402 */
 403int kdbgetularg(const char *arg, unsigned long *value)
 404{
 405	if (kstrtoul(arg, 0, value))
 406		return KDB_BADINT;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 407	return 0;
 408}
 409
 410int kdbgetu64arg(const char *arg, u64 *value)
 411{
 412	if (kstrtou64(arg, 0, value))
 413		return KDB_BADINT;
 
 
 
 
 
 
 
 
 
 
 
 
 414	return 0;
 415}
 416
 417/*
 418 * kdb_set - This function implements the 'set' command.  Alter an
 419 *	existing environment variable or create a new one.
 420 */
 421int kdb_set(int argc, const char **argv)
 422{
 423	/*
 424	 * we can be invoked two ways:
 425	 *   set var=value    argv[1]="var", argv[2]="value"
 426	 *   set var = value  argv[1]="var", argv[2]="=", argv[3]="value"
 427	 * - if the latter, shift 'em down.
 428	 */
 429	if (argc == 3) {
 430		argv[2] = argv[3];
 431		argc--;
 432	}
 433
 434	if (argc != 2)
 435		return KDB_ARGCOUNT;
 436
 437	/*
 438	 * Censor sensitive variables
 439	 */
 440	if (strcmp(argv[1], "PROMPT") == 0 &&
 441	    !kdb_check_flags(KDB_ENABLE_MEM_READ, kdb_cmd_enabled, false))
 442		return KDB_NOPERM;
 443
 444	/*
 445	 * Check for internal variables
 446	 */
 447	if (strcmp(argv[1], "KDBDEBUG") == 0) {
 448		unsigned int debugflags;
 449		int ret;
 450
 451		ret = kstrtouint(argv[2], 0, &debugflags);
 452		if (ret || debugflags & ~KDB_DEBUG_FLAG_MASK) {
 453			kdb_printf("kdb: illegal debug flags '%s'\n",
 454				    argv[2]);
 455			return 0;
 456		}
 457		kdb_flags = (kdb_flags & ~KDB_DEBUG(MASK))
 458			| (debugflags << KDB_DEBUG_FLAG_SHIFT);
 459
 460		return 0;
 461	}
 462
 463	/*
 464	 * Tokenizer squashed the '=' sign.  argv[1] is variable
 465	 * name, argv[2] = value.
 466	 */
 467	return kdb_setenv(argv[1], argv[2]);
 468}
 469
 470static int kdb_check_regs(void)
 471{
 472	if (!kdb_current_regs) {
 473		kdb_printf("No current kdb registers."
 474			   "  You may need to select another task\n");
 475		return KDB_BADREG;
 476	}
 477	return 0;
 478}
 479
 480/*
 481 * kdbgetaddrarg - This function is responsible for parsing an
 482 *	address-expression and returning the value of the expression,
 483 *	symbol name, and offset to the caller.
 484 *
 485 *	The argument may consist of a numeric value (decimal or
 486 *	hexadecimal), a symbol name, a register name (preceded by the
 487 *	percent sign), an environment variable with a numeric value
 488 *	(preceded by a dollar sign) or a simple arithmetic expression
 489 *	consisting of a symbol name, +/-, and a numeric constant value
 490 *	(offset).
 491 * Parameters:
 492 *	argc	- count of arguments in argv
 493 *	argv	- argument vector
 494 *	*nextarg - index to next unparsed argument in argv[]
 495 *	regs	- Register state at time of KDB entry
 496 * Outputs:
 497 *	*value	- receives the value of the address-expression
 498 *	*offset - receives the offset specified, if any
 499 *	*name   - receives the symbol name, if any
 500 *	*nextarg - index to next unparsed argument in argv[]
 501 * Returns:
 502 *	zero is returned on success, a kdb diagnostic code is
 503 *      returned on error.
 504 */
 505int kdbgetaddrarg(int argc, const char **argv, int *nextarg,
 506		  unsigned long *value,  long *offset,
 507		  char **name)
 508{
 509	unsigned long addr;
 510	unsigned long off = 0;
 511	int positive;
 512	int diag;
 513	int found = 0;
 514	char *symname;
 515	char symbol = '\0';
 516	char *cp;
 517	kdb_symtab_t symtab;
 518
 519	/*
 520	 * If the enable flags prohibit both arbitrary memory access
 521	 * and flow control then there are no reasonable grounds to
 522	 * provide symbol lookup.
 523	 */
 524	if (!kdb_check_flags(KDB_ENABLE_MEM_READ | KDB_ENABLE_FLOW_CTRL,
 525			     kdb_cmd_enabled, false))
 526		return KDB_NOPERM;
 527
 528	/*
 529	 * Process arguments which follow the following syntax:
 530	 *
 531	 *  symbol | numeric-address [+/- numeric-offset]
 532	 *  %register
 533	 *  $environment-variable
 534	 */
 535
 536	if (*nextarg > argc)
 537		return KDB_ARGCOUNT;
 538
 539	symname = (char *)argv[*nextarg];
 540
 541	/*
 542	 * If there is no whitespace between the symbol
 543	 * or address and the '+' or '-' symbols, we
 544	 * remember the character and replace it with a
 545	 * null so the symbol/value can be properly parsed
 546	 */
 547	cp = strpbrk(symname, "+-");
 548	if (cp != NULL) {
 549		symbol = *cp;
 550		*cp++ = '\0';
 551	}
 552
 553	if (symname[0] == '$') {
 554		diag = kdbgetulenv(&symname[1], &addr);
 555		if (diag)
 556			return diag;
 557	} else if (symname[0] == '%') {
 558		diag = kdb_check_regs();
 559		if (diag)
 560			return diag;
 561		/* Implement register values with % at a later time as it is
 562		 * arch optional.
 563		 */
 564		return KDB_NOTIMP;
 565	} else {
 566		found = kdbgetsymval(symname, &symtab);
 567		if (found) {
 568			addr = symtab.sym_start;
 569		} else {
 570			diag = kdbgetularg(argv[*nextarg], &addr);
 571			if (diag)
 572				return diag;
 573		}
 574	}
 575
 576	if (!found)
 577		found = kdbnearsym(addr, &symtab);
 578
 579	(*nextarg)++;
 580
 581	if (name)
 582		*name = symname;
 583	if (value)
 584		*value = addr;
 585	if (offset && name && *name)
 586		*offset = addr - symtab.sym_start;
 587
 588	if ((*nextarg > argc)
 589	 && (symbol == '\0'))
 590		return 0;
 591
 592	/*
 593	 * check for +/- and offset
 594	 */
 595
 596	if (symbol == '\0') {
 597		if ((argv[*nextarg][0] != '+')
 598		 && (argv[*nextarg][0] != '-')) {
 599			/*
 600			 * Not our argument.  Return.
 601			 */
 602			return 0;
 603		} else {
 604			positive = (argv[*nextarg][0] == '+');
 605			(*nextarg)++;
 606		}
 607	} else
 608		positive = (symbol == '+');
 609
 610	/*
 611	 * Now there must be an offset!
 612	 */
 613	if ((*nextarg > argc)
 614	 && (symbol == '\0')) {
 615		return KDB_INVADDRFMT;
 616	}
 617
 618	if (!symbol) {
 619		cp = (char *)argv[*nextarg];
 620		(*nextarg)++;
 621	}
 622
 623	diag = kdbgetularg(cp, &off);
 624	if (diag)
 625		return diag;
 626
 627	if (!positive)
 628		off = -off;
 629
 630	if (offset)
 631		*offset += off;
 632
 633	if (value)
 634		*value += off;
 635
 636	return 0;
 637}
 638
 639static void kdb_cmderror(int diag)
 640{
 641	int i;
 642
 643	if (diag >= 0) {
 644		kdb_printf("no error detected (diagnostic is %d)\n", diag);
 645		return;
 646	}
 647
 648	for (i = 0; i < __nkdb_err; i++) {
 649		if (kdbmsgs[i].km_diag == diag) {
 650			kdb_printf("diag: %d: %s\n", diag, kdbmsgs[i].km_msg);
 651			return;
 652		}
 653	}
 654
 655	kdb_printf("Unknown diag %d\n", -diag);
 656}
 657
 658/*
 659 * kdb_defcmd, kdb_defcmd2 - This function implements the 'defcmd'
 660 *	command which defines one command as a set of other commands,
 661 *	terminated by endefcmd.  kdb_defcmd processes the initial
 662 *	'defcmd' command, kdb_defcmd2 is invoked from kdb_parse for
 663 *	the following commands until 'endefcmd'.
 664 * Inputs:
 665 *	argc	argument count
 666 *	argv	argument vector
 667 * Returns:
 668 *	zero for success, a kdb diagnostic if error
 669 */
 670struct kdb_macro {
 671	kdbtab_t cmd;			/* Macro command */
 672	struct list_head statements;	/* Associated statement list */
 673};
 674
 675struct kdb_macro_statement {
 676	char *statement;		/* Statement text */
 677	struct list_head list_node;	/* Statement list node */
 678};
 679
 680static struct kdb_macro *kdb_macro;
 681static bool defcmd_in_progress;
 682
 683/* Forward references */
 684static int kdb_exec_defcmd(int argc, const char **argv);
 685
 686static int kdb_defcmd2(const char *cmdstr, const char *argv0)
 687{
 688	struct kdb_macro_statement *kms;
 689
 690	if (!kdb_macro)
 691		return KDB_NOTIMP;
 692
 693	if (strcmp(argv0, "endefcmd") == 0) {
 694		defcmd_in_progress = false;
 695		if (!list_empty(&kdb_macro->statements))
 696			kdb_register(&kdb_macro->cmd);
 
 
 
 
 
 
 
 
 697		return 0;
 698	}
 699
 700	kms = kmalloc(sizeof(*kms), GFP_KDB);
 701	if (!kms) {
 702		kdb_printf("Could not allocate new kdb macro command: %s\n",
 
 703			   cmdstr);
 
 704		return KDB_NOTIMP;
 705	}
 706
 707	kms->statement = kdb_strdup(cmdstr, GFP_KDB);
 708	list_add_tail(&kms->list_node, &kdb_macro->statements);
 709
 710	return 0;
 711}
 712
 713static int kdb_defcmd(int argc, const char **argv)
 714{
 715	kdbtab_t *mp;
 716
 717	if (defcmd_in_progress) {
 718		kdb_printf("kdb: nested defcmd detected, assuming missing "
 719			   "endefcmd\n");
 720		kdb_defcmd2("endefcmd", "endefcmd");
 721	}
 722	if (argc == 0) {
 723		kdbtab_t *kp;
 724		struct kdb_macro *kmp;
 725		struct kdb_macro_statement *kms;
 726
 727		list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 728			if (kp->func == kdb_exec_defcmd) {
 729				kdb_printf("defcmd %s \"%s\" \"%s\"\n",
 730					   kp->name, kp->usage, kp->help);
 731				kmp = container_of(kp, struct kdb_macro, cmd);
 732				list_for_each_entry(kms, &kmp->statements,
 733						    list_node)
 734					kdb_printf("%s", kms->statement);
 735				kdb_printf("endefcmd\n");
 736			}
 737		}
 738		return 0;
 739	}
 740	if (argc != 3)
 741		return KDB_ARGCOUNT;
 742	if (in_dbg_master()) {
 743		kdb_printf("Command only available during kdb_init()\n");
 744		return KDB_NOTIMP;
 745	}
 746	kdb_macro = kzalloc(sizeof(*kdb_macro), GFP_KDB);
 747	if (!kdb_macro)
 
 748		goto fail_defcmd;
 749
 750	mp = &kdb_macro->cmd;
 751	mp->func = kdb_exec_defcmd;
 752	mp->minlen = 0;
 753	mp->flags = KDB_ENABLE_ALWAYS_SAFE;
 754	mp->name = kdb_strdup(argv[1], GFP_KDB);
 755	if (!mp->name)
 756		goto fail_name;
 757	mp->usage = kdb_strdup(argv[2], GFP_KDB);
 758	if (!mp->usage)
 759		goto fail_usage;
 760	mp->help = kdb_strdup(argv[3], GFP_KDB);
 761	if (!mp->help)
 762		goto fail_help;
 763	if (mp->usage[0] == '"') {
 764		strcpy(mp->usage, argv[2]+1);
 765		mp->usage[strlen(mp->usage)-1] = '\0';
 766	}
 767	if (mp->help[0] == '"') {
 768		strcpy(mp->help, argv[3]+1);
 769		mp->help[strlen(mp->help)-1] = '\0';
 770	}
 771
 772	INIT_LIST_HEAD(&kdb_macro->statements);
 773	defcmd_in_progress = true;
 
 774	return 0;
 775fail_help:
 776	kfree(mp->usage);
 777fail_usage:
 778	kfree(mp->name);
 779fail_name:
 780	kfree(kdb_macro);
 781fail_defcmd:
 782	kdb_printf("Could not allocate new kdb_macro entry for %s\n", argv[1]);
 
 783	return KDB_NOTIMP;
 784}
 785
 786/*
 787 * kdb_exec_defcmd - Execute the set of commands associated with this
 788 *	defcmd name.
 789 * Inputs:
 790 *	argc	argument count
 791 *	argv	argument vector
 792 * Returns:
 793 *	zero for success, a kdb diagnostic if error
 794 */
 795static int kdb_exec_defcmd(int argc, const char **argv)
 796{
 797	int ret;
 798	kdbtab_t *kp;
 799	struct kdb_macro *kmp;
 800	struct kdb_macro_statement *kms;
 801
 802	if (argc != 0)
 803		return KDB_ARGCOUNT;
 804
 805	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
 806		if (strcmp(kp->name, argv[0]) == 0)
 807			break;
 808	}
 809	if (list_entry_is_head(kp, &kdb_cmds_head, list_node)) {
 810		kdb_printf("kdb_exec_defcmd: could not find commands for %s\n",
 811			   argv[0]);
 812		return KDB_NOTIMP;
 813	}
 814	kmp = container_of(kp, struct kdb_macro, cmd);
 815	list_for_each_entry(kms, &kmp->statements, list_node) {
 816		/*
 817		 * Recursive use of kdb_parse, do not use argv after this point.
 818		 */
 819		argv = NULL;
 820		kdb_printf("[%s]kdb> %s\n", kmp->cmd.name, kms->statement);
 821		ret = kdb_parse(kms->statement);
 822		if (ret)
 823			return ret;
 824	}
 825	return 0;
 826}
 827
 828/* Command history */
 829#define KDB_CMD_HISTORY_COUNT	32
 830#define CMD_BUFLEN		200	/* kdb_printf: max printline
 831					 * size == 256 */
 832static unsigned int cmd_head, cmd_tail;
 833static unsigned int cmdptr;
 834static char cmd_hist[KDB_CMD_HISTORY_COUNT][CMD_BUFLEN];
 835static char cmd_cur[CMD_BUFLEN];
 836
 837/*
 838 * The "str" argument may point to something like  | grep xyz
 839 */
 840static void parse_grep(const char *str)
 841{
 842	int	len;
 843	char	*cp = (char *)str, *cp2;
 844
 845	/* sanity check: we should have been called with the \ first */
 846	if (*cp != '|')
 847		return;
 848	cp++;
 849	while (isspace(*cp))
 850		cp++;
 851	if (!str_has_prefix(cp, "grep ")) {
 852		kdb_printf("invalid 'pipe', see grephelp\n");
 853		return;
 854	}
 855	cp += 5;
 856	while (isspace(*cp))
 857		cp++;
 858	cp2 = strchr(cp, '\n');
 859	if (cp2)
 860		*cp2 = '\0'; /* remove the trailing newline */
 861	len = strlen(cp);
 862	if (len == 0) {
 863		kdb_printf("invalid 'pipe', see grephelp\n");
 864		return;
 865	}
 866	/* now cp points to a nonzero length search string */
 867	if (*cp == '"') {
 868		/* allow it be "x y z" by removing the "'s - there must
 869		   be two of them */
 870		cp++;
 871		cp2 = strchr(cp, '"');
 872		if (!cp2) {
 873			kdb_printf("invalid quoted string, see grephelp\n");
 874			return;
 875		}
 876		*cp2 = '\0'; /* end the string where the 2nd " was */
 877	}
 878	kdb_grep_leading = 0;
 879	if (*cp == '^') {
 880		kdb_grep_leading = 1;
 881		cp++;
 882	}
 883	len = strlen(cp);
 884	kdb_grep_trailing = 0;
 885	if (*(cp+len-1) == '$') {
 886		kdb_grep_trailing = 1;
 887		*(cp+len-1) = '\0';
 888	}
 889	len = strlen(cp);
 890	if (!len)
 891		return;
 892	if (len >= KDB_GREP_STRLEN) {
 893		kdb_printf("search string too long\n");
 894		return;
 895	}
 896	strcpy(kdb_grep_string, cp);
 897	kdb_grepping_flag++;
 898	return;
 899}
 900
 901/*
 902 * kdb_parse - Parse the command line, search the command table for a
 903 *	matching command and invoke the command function.  This
 904 *	function may be called recursively, if it is, the second call
 905 *	will overwrite argv and cbuf.  It is the caller's
 906 *	responsibility to save their argv if they recursively call
 907 *	kdb_parse().
 908 * Parameters:
 909 *      cmdstr	The input command line to be parsed.
 910 *	regs	The registers at the time kdb was entered.
 911 * Returns:
 912 *	Zero for success, a kdb diagnostic if failure.
 913 * Remarks:
 914 *	Limited to 20 tokens.
 915 *
 916 *	Real rudimentary tokenization. Basically only whitespace
 917 *	is considered a token delimiter (but special consideration
 918 *	is taken of the '=' sign as used by the 'set' command).
 919 *
 920 *	The algorithm used to tokenize the input string relies on
 921 *	there being at least one whitespace (or otherwise useless)
 922 *	character between tokens as the character immediately following
 923 *	the token is altered in-place to a null-byte to terminate the
 924 *	token string.
 925 */
 926
 927#define MAXARGC	20
 928
 929int kdb_parse(const char *cmdstr)
 930{
 931	static char *argv[MAXARGC];
 932	static int argc;
 933	static char cbuf[CMD_BUFLEN+2];
 934	char *cp;
 935	char *cpp, quoted;
 936	kdbtab_t *tp;
 937	int escaped, ignore_errors = 0, check_grep = 0;
 938
 939	/*
 940	 * First tokenize the command string.
 941	 */
 942	cp = (char *)cmdstr;
 943
 944	if (KDB_FLAG(CMD_INTERRUPT)) {
 945		/* Previous command was interrupted, newline must not
 946		 * repeat the command */
 947		KDB_FLAG_CLEAR(CMD_INTERRUPT);
 948		KDB_STATE_SET(PAGER);
 949		argc = 0;	/* no repeat */
 950	}
 951
 952	if (*cp != '\n' && *cp != '\0') {
 953		argc = 0;
 954		cpp = cbuf;
 955		while (*cp) {
 956			/* skip whitespace */
 957			while (isspace(*cp))
 958				cp++;
 959			if ((*cp == '\0') || (*cp == '\n') ||
 960			    (*cp == '#' && !defcmd_in_progress))
 961				break;
 962			/* special case: check for | grep pattern */
 963			if (*cp == '|') {
 964				check_grep++;
 965				break;
 966			}
 967			if (cpp >= cbuf + CMD_BUFLEN) {
 968				kdb_printf("kdb_parse: command buffer "
 969					   "overflow, command ignored\n%s\n",
 970					   cmdstr);
 971				return KDB_NOTFOUND;
 972			}
 973			if (argc >= MAXARGC - 1) {
 974				kdb_printf("kdb_parse: too many arguments, "
 975					   "command ignored\n%s\n", cmdstr);
 976				return KDB_NOTFOUND;
 977			}
 978			argv[argc++] = cpp;
 979			escaped = 0;
 980			quoted = '\0';
 981			/* Copy to next unquoted and unescaped
 982			 * whitespace or '=' */
 983			while (*cp && *cp != '\n' &&
 984			       (escaped || quoted || !isspace(*cp))) {
 985				if (cpp >= cbuf + CMD_BUFLEN)
 986					break;
 987				if (escaped) {
 988					escaped = 0;
 989					*cpp++ = *cp++;
 990					continue;
 991				}
 992				if (*cp == '\\') {
 993					escaped = 1;
 994					++cp;
 995					continue;
 996				}
 997				if (*cp == quoted)
 998					quoted = '\0';
 999				else if (*cp == '\'' || *cp == '"')
1000					quoted = *cp;
1001				*cpp = *cp++;
1002				if (*cpp == '=' && !quoted)
1003					break;
1004				++cpp;
1005			}
1006			*cpp++ = '\0';	/* Squash a ws or '=' character */
1007		}
1008	}
1009	if (!argc)
1010		return 0;
1011	if (check_grep)
1012		parse_grep(cp);
1013	if (defcmd_in_progress) {
1014		int result = kdb_defcmd2(cmdstr, argv[0]);
1015		if (!defcmd_in_progress) {
1016			argc = 0;	/* avoid repeat on endefcmd */
1017			*(argv[0]) = '\0';
1018		}
1019		return result;
1020	}
1021	if (argv[0][0] == '-' && argv[0][1] &&
1022	    (argv[0][1] < '0' || argv[0][1] > '9')) {
1023		ignore_errors = 1;
1024		++argv[0];
1025	}
1026
1027	list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1028		/*
1029		 * If this command is allowed to be abbreviated,
1030		 * check to see if this is it.
1031		 */
1032		if (tp->minlen && (strlen(argv[0]) <= tp->minlen) &&
1033		    (strncmp(argv[0], tp->name, tp->minlen) == 0))
1034			break;
1035
1036		if (strcmp(argv[0], tp->name) == 0)
1037			break;
1038	}
1039
1040	/*
1041	 * If we don't find a command by this name, see if the first
1042	 * few characters of this match any of the known commands.
1043	 * e.g., md1c20 should match md.
1044	 */
1045	if (list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1046		list_for_each_entry(tp, &kdb_cmds_head, list_node) {
1047			if (strncmp(argv[0], tp->name, strlen(tp->name)) == 0)
 
1048				break;
1049		}
1050	}
1051
1052	if (!list_entry_is_head(tp, &kdb_cmds_head, list_node)) {
1053		int result;
1054
1055		if (!kdb_check_flags(tp->flags, kdb_cmd_enabled, argc <= 1))
1056			return KDB_NOPERM;
1057
1058		KDB_STATE_SET(CMD);
1059		result = (*tp->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->flags & KDB_REPEAT_WITH_ARGS)
1065			return result;
1066
1067		argc = tp->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		curr_task(raw_smp_processor_id());
1195
1196	KDB_DEBUG_STATE("kdb_local 1", reason);
1197
1198	kdb_check_for_lockdown();
1199
1200	kdb_go_count = 0;
1201	if (reason == KDB_REASON_DEBUG) {
1202		/* special case below */
1203	} else {
1204		kdb_printf("\nEntering kdb (current=0x%px, pid %d) ",
1205			   kdb_current, kdb_current ? kdb_current->pid : 0);
1206#if defined(CONFIG_SMP)
1207		kdb_printf("on processor %d ", raw_smp_processor_id());
1208#endif
1209	}
1210
1211	switch (reason) {
1212	case KDB_REASON_DEBUG:
1213	{
1214		/*
1215		 * If re-entering kdb after a single step
1216		 * command, don't print the message.
1217		 */
1218		switch (db_result) {
1219		case KDB_DB_BPT:
1220			kdb_printf("\nEntering kdb (0x%px, pid %d) ",
1221				   kdb_current, kdb_current->pid);
1222#if defined(CONFIG_SMP)
1223			kdb_printf("on processor %d ", raw_smp_processor_id());
1224#endif
1225			kdb_printf("due to Debug @ " kdb_machreg_fmt "\n",
1226				   instruction_pointer(regs));
1227			break;
1228		case KDB_DB_SS:
1229			break;
1230		case KDB_DB_SSBPT:
1231			KDB_DEBUG_STATE("kdb_local 4", reason);
1232			return 1;	/* kdba_db_trap did the work */
1233		default:
1234			kdb_printf("kdb: Bad result from kdba_db_trap: %d\n",
1235				   db_result);
1236			break;
1237		}
1238
1239	}
1240		break;
1241	case KDB_REASON_ENTER:
1242		if (KDB_STATE(KEYBOARD))
1243			kdb_printf("due to Keyboard Entry\n");
1244		else
1245			kdb_printf("due to KDB_ENTER()\n");
1246		break;
1247	case KDB_REASON_KEYBOARD:
1248		KDB_STATE_SET(KEYBOARD);
1249		kdb_printf("due to Keyboard Entry\n");
1250		break;
1251	case KDB_REASON_ENTER_SLAVE:
1252		/* drop through, slaves only get released via cpu switch */
1253	case KDB_REASON_SWITCH:
1254		kdb_printf("due to cpu switch\n");
1255		break;
1256	case KDB_REASON_OOPS:
1257		kdb_printf("Oops: %s\n", kdb_diemsg);
1258		kdb_printf("due to oops @ " kdb_machreg_fmt "\n",
1259			   instruction_pointer(regs));
1260		kdb_dumpregs(regs);
1261		break;
1262	case KDB_REASON_SYSTEM_NMI:
1263		kdb_printf("due to System NonMaskable Interrupt\n");
1264		break;
1265	case KDB_REASON_NMI:
1266		kdb_printf("due to NonMaskable Interrupt @ "
1267			   kdb_machreg_fmt "\n",
1268			   instruction_pointer(regs));
1269		break;
1270	case KDB_REASON_SSTEP:
1271	case KDB_REASON_BREAK:
1272		kdb_printf("due to %s @ " kdb_machreg_fmt "\n",
1273			   reason == KDB_REASON_BREAK ?
1274			   "Breakpoint" : "SS trap", instruction_pointer(regs));
1275		/*
1276		 * Determine if this breakpoint is one that we
1277		 * are interested in.
1278		 */
1279		if (db_result != KDB_DB_BPT) {
1280			kdb_printf("kdb: error return from kdba_bp_trap: %d\n",
1281				   db_result);
1282			KDB_DEBUG_STATE("kdb_local 6", reason);
1283			return 0;	/* Not for us, dismiss it */
1284		}
1285		break;
1286	case KDB_REASON_RECURSE:
1287		kdb_printf("due to Recursion @ " kdb_machreg_fmt "\n",
1288			   instruction_pointer(regs));
1289		break;
1290	default:
1291		kdb_printf("kdb: unexpected reason code: %d\n", reason);
1292		KDB_DEBUG_STATE("kdb_local 8", reason);
1293		return 0;	/* Not for us, dismiss it */
1294	}
1295
1296	while (1) {
1297		/*
1298		 * Initialize pager context.
1299		 */
1300		kdb_nextline = 1;
1301		KDB_STATE_CLEAR(SUPPRESS);
1302		kdb_grepping_flag = 0;
1303		/* ensure the old search does not leak into '/' commands */
1304		kdb_grep_string[0] = '\0';
1305
1306		cmdbuf = cmd_cur;
1307		*cmdbuf = '\0';
1308		*(cmd_hist[cmd_head]) = '\0';
1309
1310do_full_getstr:
1311		/* PROMPT can only be set if we have MEM_READ permission. */
1312		snprintf(kdb_prompt_str, CMD_BUFLEN, kdbgetenv("PROMPT"),
1313			 raw_smp_processor_id());
 
 
1314
1315		/*
1316		 * Fetch command from keyboard
1317		 */
1318		cmdbuf = kdb_getstr(cmdbuf, CMD_BUFLEN, kdb_prompt_str);
1319		if (*cmdbuf != '\n') {
1320			if (*cmdbuf < 32) {
1321				if (cmdptr == cmd_head) {
1322					strscpy(cmd_hist[cmd_head], cmd_cur,
1323						CMD_BUFLEN);
1324					*(cmd_hist[cmd_head] +
1325					  strlen(cmd_hist[cmd_head])-1) = '\0';
1326				}
1327				if (!handle_ctrl_cmd(cmdbuf))
1328					*(cmd_cur+strlen(cmd_cur)-1) = '\0';
1329				cmdbuf = cmd_cur;
1330				goto do_full_getstr;
1331			} else {
1332				strscpy(cmd_hist[cmd_head], cmd_cur,
1333					CMD_BUFLEN);
1334			}
1335
1336			cmd_head = (cmd_head+1) % KDB_CMD_HISTORY_COUNT;
1337			if (cmd_head == cmd_tail)
1338				cmd_tail = (cmd_tail+1) % KDB_CMD_HISTORY_COUNT;
1339		}
1340
1341		cmdptr = cmd_head;
1342		diag = kdb_parse(cmdbuf);
1343		if (diag == KDB_NOTFOUND) {
1344			drop_newline(cmdbuf);
1345			kdb_printf("Unknown kdb command: '%s'\n", cmdbuf);
1346			diag = 0;
1347		}
1348		if (diag == KDB_CMD_GO
1349		 || diag == KDB_CMD_CPU
1350		 || diag == KDB_CMD_SS
1351		 || diag == KDB_CMD_KGDB)
1352			break;
1353
1354		if (diag)
1355			kdb_cmderror(diag);
1356	}
1357	KDB_DEBUG_STATE("kdb_local 9", diag);
1358	return diag;
1359}
1360
1361
1362/*
1363 * kdb_print_state - Print the state data for the current processor
1364 *	for debugging.
1365 * Inputs:
1366 *	text		Identifies the debug point
1367 *	value		Any integer value to be printed, e.g. reason code.
1368 */
1369void kdb_print_state(const char *text, int value)
1370{
1371	kdb_printf("state: %s cpu %d value %d initial %d state %x\n",
1372		   text, raw_smp_processor_id(), value, kdb_initial_cpu,
1373		   kdb_state);
1374}
1375
1376/*
1377 * kdb_main_loop - After initial setup and assignment of the
1378 *	controlling cpu, all cpus are in this loop.  One cpu is in
1379 *	control and will issue the kdb prompt, the others will spin
1380 *	until 'go' or cpu switch.
1381 *
1382 *	To get a consistent view of the kernel stacks for all
1383 *	processes, this routine is invoked from the main kdb code via
1384 *	an architecture specific routine.  kdba_main_loop is
1385 *	responsible for making the kernel stacks consistent for all
1386 *	processes, there should be no difference between a blocked
1387 *	process and a running process as far as kdb is concerned.
1388 * Inputs:
1389 *	reason		The reason KDB was invoked
1390 *	error		The hardware-defined error code
1391 *	reason2		kdb's current reason code.
1392 *			Initially error but can change
1393 *			according to kdb state.
1394 *	db_result	Result code from break or debug point.
1395 *	regs		The exception frame at time of fault/breakpoint.
1396 *			should always be valid.
1397 * Returns:
1398 *	0	KDB was invoked for an event which it wasn't responsible
1399 *	1	KDB handled the event for which it was invoked.
1400 */
1401int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
1402	      kdb_dbtrap_t db_result, struct pt_regs *regs)
1403{
1404	int result = 1;
1405	/* Stay in kdb() until 'go', 'ss[b]' or an error */
1406	while (1) {
1407		/*
1408		 * All processors except the one that is in control
1409		 * will spin here.
1410		 */
1411		KDB_DEBUG_STATE("kdb_main_loop 1", reason);
1412		while (KDB_STATE(HOLD_CPU)) {
1413			/* state KDB is turned off by kdb_cpu to see if the
1414			 * other cpus are still live, each cpu in this loop
1415			 * turns it back on.
1416			 */
1417			if (!KDB_STATE(KDB))
1418				KDB_STATE_SET(KDB);
1419		}
1420
1421		KDB_STATE_CLEAR(SUPPRESS);
1422		KDB_DEBUG_STATE("kdb_main_loop 2", reason);
1423		if (KDB_STATE(LEAVING))
1424			break;	/* Another cpu said 'go' */
1425		/* Still using kdb, this processor is in control */
1426		result = kdb_local(reason2, error, regs, db_result);
1427		KDB_DEBUG_STATE("kdb_main_loop 3", result);
1428
1429		if (result == KDB_CMD_CPU)
1430			break;
1431
1432		if (result == KDB_CMD_SS) {
1433			KDB_STATE_SET(DOING_SS);
1434			break;
1435		}
1436
1437		if (result == KDB_CMD_KGDB) {
1438			if (!KDB_STATE(DOING_KGDB))
1439				kdb_printf("Entering please attach debugger "
1440					   "or use $D#44+ or $3#33\n");
1441			break;
1442		}
1443		if (result && result != 1 && result != KDB_CMD_GO)
1444			kdb_printf("\nUnexpected kdb_local return code %d\n",
1445				   result);
1446		KDB_DEBUG_STATE("kdb_main_loop 4", reason);
1447		break;
1448	}
1449	if (KDB_STATE(DOING_SS))
1450		KDB_STATE_CLEAR(SSBPT);
1451
1452	/* Clean up any keyboard devices before leaving */
1453	kdb_kbd_cleanup_state();
1454
1455	return result;
1456}
1457
1458/*
1459 * kdb_mdr - This function implements the guts of the 'mdr', memory
1460 * read command.
1461 *	mdr  <addr arg>,<byte count>
1462 * Inputs:
1463 *	addr	Start address
1464 *	count	Number of bytes
1465 * Returns:
1466 *	Always 0.  Any errors are detected and printed by kdb_getarea.
1467 */
1468static int kdb_mdr(unsigned long addr, unsigned int count)
1469{
1470	unsigned char c;
1471	while (count--) {
1472		if (kdb_getarea(c, addr))
1473			return 0;
1474		kdb_printf("%02x", c);
1475		addr++;
1476	}
1477	kdb_printf("\n");
1478	return 0;
1479}
1480
1481/*
1482 * kdb_md - This function implements the 'md', 'md1', 'md2', 'md4',
1483 *	'md8' 'mdr' and 'mds' commands.
1484 *
1485 *	md|mds  [<addr arg> [<line count> [<radix>]]]
1486 *	mdWcN	[<addr arg> [<line count> [<radix>]]]
1487 *		where W = is the width (1, 2, 4 or 8) and N is the count.
1488 *		for eg., md1c20 reads 20 bytes, 1 at a time.
1489 *	mdr  <addr arg>,<byte count>
1490 */
1491static void kdb_md_line(const char *fmtstr, unsigned long addr,
1492			int symbolic, int nosect, int bytesperword,
1493			int num, int repeat, int phys)
1494{
1495	/* print just one line of data */
1496	kdb_symtab_t symtab;
1497	char cbuf[32];
1498	char *c = cbuf;
1499	int i;
1500	int j;
1501	unsigned long word;
1502
1503	memset(cbuf, '\0', sizeof(cbuf));
1504	if (phys)
1505		kdb_printf("phys " kdb_machreg_fmt0 " ", addr);
1506	else
1507		kdb_printf(kdb_machreg_fmt0 " ", addr);
1508
1509	for (i = 0; i < num && repeat--; i++) {
1510		if (phys) {
1511			if (kdb_getphysword(&word, addr, bytesperword))
1512				break;
1513		} else if (kdb_getword(&word, addr, bytesperword))
1514			break;
1515		kdb_printf(fmtstr, word);
1516		if (symbolic)
1517			kdbnearsym(word, &symtab);
1518		else
1519			memset(&symtab, 0, sizeof(symtab));
1520		if (symtab.sym_name) {
1521			kdb_symbol_print(word, &symtab, 0);
1522			if (!nosect) {
1523				kdb_printf("\n");
1524				kdb_printf("                       %s %s "
1525					   kdb_machreg_fmt " "
1526					   kdb_machreg_fmt " "
1527					   kdb_machreg_fmt, symtab.mod_name,
1528					   symtab.sec_name, symtab.sec_start,
1529					   symtab.sym_start, symtab.sym_end);
1530			}
1531			addr += bytesperword;
1532		} else {
1533			union {
1534				u64 word;
1535				unsigned char c[8];
1536			} wc;
1537			unsigned char *cp;
1538#ifdef	__BIG_ENDIAN
1539			cp = wc.c + 8 - bytesperword;
1540#else
1541			cp = wc.c;
1542#endif
1543			wc.word = word;
1544#define printable_char(c) \
1545	({unsigned char __c = c; isascii(__c) && isprint(__c) ? __c : '.'; })
1546			for (j = 0; j < bytesperword; j++)
1547				*c++ = printable_char(*cp++);
1548			addr += bytesperword;
1549#undef printable_char
1550		}
1551	}
1552	kdb_printf("%*s %s\n", (int)((num-i)*(2*bytesperword + 1)+1),
1553		   " ", cbuf);
1554}
1555
1556static int kdb_md(int argc, const char **argv)
1557{
1558	static unsigned long last_addr;
1559	static int last_radix, last_bytesperword, last_repeat;
1560	int radix = 16, mdcount = 8, bytesperword = KDB_WORD_SIZE, repeat;
1561	int nosect = 0;
1562	char fmtchar, fmtstr[64];
1563	unsigned long addr;
1564	unsigned long word;
1565	long offset = 0;
1566	int symbolic = 0;
1567	int valid = 0;
1568	int phys = 0;
1569	int raw = 0;
1570
1571	kdbgetintenv("MDCOUNT", &mdcount);
1572	kdbgetintenv("RADIX", &radix);
1573	kdbgetintenv("BYTESPERWORD", &bytesperword);
1574
1575	/* Assume 'md <addr>' and start with environment values */
1576	repeat = mdcount * 16 / bytesperword;
1577
1578	if (strcmp(argv[0], "mdr") == 0) {
1579		if (argc == 2 || (argc == 0 && last_addr != 0))
1580			valid = raw = 1;
1581		else
1582			return KDB_ARGCOUNT;
1583	} else if (isdigit(argv[0][2])) {
1584		bytesperword = (int)(argv[0][2] - '0');
1585		if (bytesperword == 0) {
1586			bytesperword = last_bytesperword;
1587			if (bytesperword == 0)
1588				bytesperword = 4;
1589		}
1590		last_bytesperword = bytesperword;
1591		repeat = mdcount * 16 / bytesperword;
1592		if (!argv[0][3])
1593			valid = 1;
1594		else if (argv[0][3] == 'c' && argv[0][4]) {
1595			if (kstrtouint(argv[0] + 4, 10, &repeat))
1596				return KDB_BADINT;
1597			mdcount = ((repeat * bytesperword) + 15) / 16;
1598			valid = 1;
1599		}
1600		last_repeat = repeat;
1601	} else if (strcmp(argv[0], "md") == 0)
1602		valid = 1;
1603	else if (strcmp(argv[0], "mds") == 0)
1604		valid = 1;
1605	else if (strcmp(argv[0], "mdp") == 0) {
1606		phys = valid = 1;
1607	}
1608	if (!valid)
1609		return KDB_NOTFOUND;
1610
1611	if (argc == 0) {
1612		if (last_addr == 0)
1613			return KDB_ARGCOUNT;
1614		addr = last_addr;
1615		radix = last_radix;
1616		bytesperword = last_bytesperword;
1617		repeat = last_repeat;
1618		if (raw)
1619			mdcount = repeat;
1620		else
1621			mdcount = ((repeat * bytesperword) + 15) / 16;
1622	}
1623
1624	if (argc) {
1625		unsigned long val;
1626		int diag, nextarg = 1;
1627		diag = kdbgetaddrarg(argc, argv, &nextarg, &addr,
1628				     &offset, NULL);
1629		if (diag)
1630			return diag;
1631		if (argc > nextarg+2)
1632			return KDB_ARGCOUNT;
1633
1634		if (argc >= nextarg) {
1635			diag = kdbgetularg(argv[nextarg], &val);
1636			if (!diag) {
1637				mdcount = (int) val;
1638				if (raw)
1639					repeat = mdcount;
1640				else
1641					repeat = mdcount * 16 / bytesperword;
1642			}
1643		}
1644		if (argc >= nextarg+1) {
1645			diag = kdbgetularg(argv[nextarg+1], &val);
1646			if (!diag)
1647				radix = (int) val;
1648		}
1649	}
1650
1651	if (strcmp(argv[0], "mdr") == 0) {
1652		int ret;
1653		last_addr = addr;
1654		ret = kdb_mdr(addr, mdcount);
1655		last_addr += mdcount;
1656		last_repeat = mdcount;
1657		last_bytesperword = bytesperword; // to make REPEAT happy
1658		return ret;
1659	}
1660
1661	switch (radix) {
1662	case 10:
1663		fmtchar = 'd';
1664		break;
1665	case 16:
1666		fmtchar = 'x';
1667		break;
1668	case 8:
1669		fmtchar = 'o';
1670		break;
1671	default:
1672		return KDB_BADRADIX;
1673	}
1674
1675	last_radix = radix;
1676
1677	if (bytesperword > KDB_WORD_SIZE)
1678		return KDB_BADWIDTH;
1679
1680	switch (bytesperword) {
1681	case 8:
1682		sprintf(fmtstr, "%%16.16l%c ", fmtchar);
1683		break;
1684	case 4:
1685		sprintf(fmtstr, "%%8.8l%c ", fmtchar);
1686		break;
1687	case 2:
1688		sprintf(fmtstr, "%%4.4l%c ", fmtchar);
1689		break;
1690	case 1:
1691		sprintf(fmtstr, "%%2.2l%c ", fmtchar);
1692		break;
1693	default:
1694		return KDB_BADWIDTH;
1695	}
1696
1697	last_repeat = repeat;
1698	last_bytesperword = bytesperword;
1699
1700	if (strcmp(argv[0], "mds") == 0) {
1701		symbolic = 1;
1702		/* Do not save these changes as last_*, they are temporary mds
1703		 * overrides.
1704		 */
1705		bytesperword = KDB_WORD_SIZE;
1706		repeat = mdcount;
1707		kdbgetintenv("NOSECT", &nosect);
1708	}
1709
1710	/* Round address down modulo BYTESPERWORD */
1711
1712	addr &= ~(bytesperword-1);
1713
1714	while (repeat > 0) {
1715		unsigned long a;
1716		int n, z, num = (symbolic ? 1 : (16 / bytesperword));
1717
1718		if (KDB_FLAG(CMD_INTERRUPT))
1719			return 0;
1720		for (a = addr, z = 0; z < repeat; a += bytesperword, ++z) {
1721			if (phys) {
1722				if (kdb_getphysword(&word, a, bytesperword)
1723						|| word)
1724					break;
1725			} else if (kdb_getword(&word, a, bytesperword) || word)
1726				break;
1727		}
1728		n = min(num, repeat);
1729		kdb_md_line(fmtstr, addr, symbolic, nosect, bytesperword,
1730			    num, repeat, phys);
1731		addr += bytesperword * n;
1732		repeat -= n;
1733		z = (z + num - 1) / num;
1734		if (z > 2) {
1735			int s = num * (z-2);
1736			kdb_printf(kdb_machreg_fmt0 "-" kdb_machreg_fmt0
1737				   " zero suppressed\n",
1738				addr, addr + bytesperword * s - 1);
1739			addr += bytesperword * s;
1740			repeat -= s;
1741		}
1742	}
1743	last_addr = addr;
1744
1745	return 0;
1746}
1747
1748/*
1749 * kdb_mm - This function implements the 'mm' command.
1750 *	mm address-expression new-value
1751 * Remarks:
1752 *	mm works on machine words, mmW works on bytes.
1753 */
1754static int kdb_mm(int argc, const char **argv)
1755{
1756	int diag;
1757	unsigned long addr;
1758	long offset = 0;
1759	unsigned long contents;
1760	int nextarg;
1761	int width;
1762
1763	if (argv[0][2] && !isdigit(argv[0][2]))
1764		return KDB_NOTFOUND;
1765
1766	if (argc < 2)
1767		return KDB_ARGCOUNT;
1768
1769	nextarg = 1;
1770	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
1771	if (diag)
1772		return diag;
1773
1774	if (nextarg > argc)
1775		return KDB_ARGCOUNT;
1776	diag = kdbgetaddrarg(argc, argv, &nextarg, &contents, NULL, NULL);
1777	if (diag)
1778		return diag;
1779
1780	if (nextarg != argc + 1)
1781		return KDB_ARGCOUNT;
1782
1783	width = argv[0][2] ? (argv[0][2] - '0') : (KDB_WORD_SIZE);
1784	diag = kdb_putword(addr, contents, width);
1785	if (diag)
1786		return diag;
1787
1788	kdb_printf(kdb_machreg_fmt " = " kdb_machreg_fmt "\n", addr, contents);
1789
1790	return 0;
1791}
1792
1793/*
1794 * kdb_go - This function implements the 'go' command.
1795 *	go [address-expression]
1796 */
1797static int kdb_go(int argc, const char **argv)
1798{
1799	unsigned long addr;
1800	int diag;
1801	int nextarg;
1802	long offset;
1803
1804	if (raw_smp_processor_id() != kdb_initial_cpu) {
1805		kdb_printf("go must execute on the entry cpu, "
1806			   "please use \"cpu %d\" and then execute go\n",
1807			   kdb_initial_cpu);
1808		return KDB_BADCPUNUM;
1809	}
1810	if (argc == 1) {
1811		nextarg = 1;
1812		diag = kdbgetaddrarg(argc, argv, &nextarg,
1813				     &addr, &offset, NULL);
1814		if (diag)
1815			return diag;
1816	} else if (argc) {
1817		return KDB_ARGCOUNT;
1818	}
1819
1820	diag = KDB_CMD_GO;
1821	if (KDB_FLAG(CATASTROPHIC)) {
1822		kdb_printf("Catastrophic error detected\n");
1823		kdb_printf("kdb_continue_catastrophic=%d, ",
1824			kdb_continue_catastrophic);
1825		if (kdb_continue_catastrophic == 0 && kdb_go_count++ == 0) {
1826			kdb_printf("type go a second time if you really want "
1827				   "to continue\n");
1828			return 0;
1829		}
1830		if (kdb_continue_catastrophic == 2) {
1831			kdb_printf("forcing reboot\n");
1832			kdb_reboot(0, NULL);
1833		}
1834		kdb_printf("attempting to continue\n");
1835	}
1836	return diag;
1837}
1838
1839/*
1840 * kdb_rd - This function implements the 'rd' command.
1841 */
1842static int kdb_rd(int argc, const char **argv)
1843{
1844	int len = kdb_check_regs();
1845#if DBG_MAX_REG_NUM > 0
1846	int i;
1847	char *rname;
1848	int rsize;
1849	u64 reg64;
1850	u32 reg32;
1851	u16 reg16;
1852	u8 reg8;
1853
1854	if (len)
1855		return len;
1856
1857	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1858		rsize = dbg_reg_def[i].size * 2;
1859		if (rsize > 16)
1860			rsize = 2;
1861		if (len + strlen(dbg_reg_def[i].name) + 4 + rsize > 80) {
1862			len = 0;
1863			kdb_printf("\n");
1864		}
1865		if (len)
1866			len += kdb_printf("  ");
1867		switch(dbg_reg_def[i].size * 8) {
1868		case 8:
1869			rname = dbg_get_reg(i, &reg8, kdb_current_regs);
1870			if (!rname)
1871				break;
1872			len += kdb_printf("%s: %02x", rname, reg8);
1873			break;
1874		case 16:
1875			rname = dbg_get_reg(i, &reg16, kdb_current_regs);
1876			if (!rname)
1877				break;
1878			len += kdb_printf("%s: %04x", rname, reg16);
1879			break;
1880		case 32:
1881			rname = dbg_get_reg(i, &reg32, kdb_current_regs);
1882			if (!rname)
1883				break;
1884			len += kdb_printf("%s: %08x", rname, reg32);
1885			break;
1886		case 64:
1887			rname = dbg_get_reg(i, &reg64, kdb_current_regs);
1888			if (!rname)
1889				break;
1890			len += kdb_printf("%s: %016llx", rname, reg64);
1891			break;
1892		default:
1893			len += kdb_printf("%s: ??", dbg_reg_def[i].name);
1894		}
1895	}
1896	kdb_printf("\n");
1897#else
1898	if (len)
1899		return len;
1900
1901	kdb_dumpregs(kdb_current_regs);
1902#endif
1903	return 0;
1904}
1905
1906/*
1907 * kdb_rm - This function implements the 'rm' (register modify)  command.
1908 *	rm register-name new-contents
1909 * Remarks:
1910 *	Allows register modification with the same restrictions as gdb
1911 */
1912static int kdb_rm(int argc, const char **argv)
1913{
1914#if DBG_MAX_REG_NUM > 0
1915	int diag;
1916	const char *rname;
1917	int i;
1918	u64 reg64;
1919	u32 reg32;
1920	u16 reg16;
1921	u8 reg8;
1922
1923	if (argc != 2)
1924		return KDB_ARGCOUNT;
1925	/*
1926	 * Allow presence or absence of leading '%' symbol.
1927	 */
1928	rname = argv[1];
1929	if (*rname == '%')
1930		rname++;
1931
1932	diag = kdbgetu64arg(argv[2], &reg64);
1933	if (diag)
1934		return diag;
1935
1936	diag = kdb_check_regs();
1937	if (diag)
1938		return diag;
1939
1940	diag = KDB_BADREG;
1941	for (i = 0; i < DBG_MAX_REG_NUM; i++) {
1942		if (strcmp(rname, dbg_reg_def[i].name) == 0) {
1943			diag = 0;
1944			break;
1945		}
1946	}
1947	if (!diag) {
1948		switch(dbg_reg_def[i].size * 8) {
1949		case 8:
1950			reg8 = reg64;
1951			dbg_set_reg(i, &reg8, kdb_current_regs);
1952			break;
1953		case 16:
1954			reg16 = reg64;
1955			dbg_set_reg(i, &reg16, kdb_current_regs);
1956			break;
1957		case 32:
1958			reg32 = reg64;
1959			dbg_set_reg(i, &reg32, kdb_current_regs);
1960			break;
1961		case 64:
1962			dbg_set_reg(i, &reg64, kdb_current_regs);
1963			break;
1964		}
1965	}
1966	return diag;
1967#else
1968	kdb_printf("ERROR: Register set currently not implemented\n");
1969    return 0;
1970#endif
1971}
1972
1973#if defined(CONFIG_MAGIC_SYSRQ)
1974/*
1975 * kdb_sr - This function implements the 'sr' (SYSRQ key) command
1976 *	which interfaces to the soi-disant MAGIC SYSRQ functionality.
1977 *		sr <magic-sysrq-code>
1978 */
1979static int kdb_sr(int argc, const char **argv)
1980{
1981	bool check_mask =
1982	    !kdb_check_flags(KDB_ENABLE_ALL, kdb_cmd_enabled, false);
1983
1984	if (argc != 1)
1985		return KDB_ARGCOUNT;
1986
1987	kdb_trap_printk++;
1988	__handle_sysrq(*argv[1], check_mask);
1989	kdb_trap_printk--;
1990
1991	return 0;
1992}
1993#endif	/* CONFIG_MAGIC_SYSRQ */
1994
1995/*
1996 * kdb_ef - This function implements the 'regs' (display exception
1997 *	frame) command.  This command takes an address and expects to
1998 *	find an exception frame at that address, formats and prints
1999 *	it.
2000 *		regs address-expression
2001 * Remarks:
2002 *	Not done yet.
2003 */
2004static int kdb_ef(int argc, const char **argv)
2005{
2006	int diag;
2007	unsigned long addr;
2008	long offset;
2009	int nextarg;
2010
2011	if (argc != 1)
2012		return KDB_ARGCOUNT;
2013
2014	nextarg = 1;
2015	diag = kdbgetaddrarg(argc, argv, &nextarg, &addr, &offset, NULL);
2016	if (diag)
2017		return diag;
2018	show_regs((struct pt_regs *)addr);
2019	return 0;
2020}
2021
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2022/*
2023 * kdb_env - This function implements the 'env' command.  Display the
2024 *	current environment variables.
2025 */
2026
2027static int kdb_env(int argc, const char **argv)
2028{
2029	kdb_printenv();
2030
2031	if (KDB_DEBUG(MASK))
2032		kdb_printf("KDBDEBUG=0x%x\n",
2033			(kdb_flags & KDB_DEBUG(MASK)) >> KDB_DEBUG_FLAG_SHIFT);
2034
2035	return 0;
2036}
2037
2038#ifdef CONFIG_PRINTK
2039/*
2040 * kdb_dmesg - This function implements the 'dmesg' command to display
2041 *	the contents of the syslog buffer.
2042 *		dmesg [lines] [adjust]
2043 */
2044static int kdb_dmesg(int argc, const char **argv)
2045{
2046	int diag;
2047	int logging;
2048	int lines = 0;
2049	int adjust = 0;
2050	int n = 0;
2051	int skip = 0;
2052	struct kmsg_dump_iter iter;
2053	size_t len;
2054	char buf[201];
2055
2056	if (argc > 2)
2057		return KDB_ARGCOUNT;
2058	if (argc) {
2059		if (kstrtoint(argv[1], 0, &lines))
 
 
2060			lines = 0;
2061		if (argc > 1 && (kstrtoint(argv[2], 0, &adjust) || adjust < 0))
2062			adjust = 0;
 
 
 
2063	}
2064
2065	/* disable LOGGING if set */
2066	diag = kdbgetintenv("LOGGING", &logging);
2067	if (!diag && logging) {
2068		const char *setargs[] = { "set", "LOGGING", "0" };
2069		kdb_set(2, setargs);
2070	}
2071
2072	kmsg_dump_rewind(&iter);
2073	while (kmsg_dump_get_line(&iter, 1, NULL, 0, NULL))
2074		n++;
2075
2076	if (lines < 0) {
2077		if (adjust >= n)
2078			kdb_printf("buffer only contains %d lines, nothing "
2079				   "printed\n", n);
2080		else if (adjust - lines >= n)
2081			kdb_printf("buffer only contains %d lines, last %d "
2082				   "lines printed\n", n, n - adjust);
2083		skip = adjust;
2084		lines = abs(lines);
2085	} else if (lines > 0) {
2086		skip = n - lines - adjust;
2087		lines = abs(lines);
2088		if (adjust >= n) {
2089			kdb_printf("buffer only contains %d lines, "
2090				   "nothing printed\n", n);
2091			skip = n;
2092		} else if (skip < 0) {
2093			lines += skip;
2094			skip = 0;
2095			kdb_printf("buffer only contains %d lines, first "
2096				   "%d lines printed\n", n, lines);
2097		}
2098	} else {
2099		lines = n;
2100	}
2101
2102	if (skip >= n || skip < 0)
2103		return 0;
2104
2105	kmsg_dump_rewind(&iter);
2106	while (kmsg_dump_get_line(&iter, 1, buf, sizeof(buf), &len)) {
2107		if (skip) {
2108			skip--;
2109			continue;
2110		}
2111		if (!lines--)
2112			break;
2113		if (KDB_FLAG(CMD_INTERRUPT))
2114			return 0;
2115
2116		kdb_printf("%.*s\n", (int)len - 1, buf);
2117	}
2118
2119	return 0;
2120}
2121#endif /* CONFIG_PRINTK */
2122
2123/* Make sure we balance enable/disable calls, must disable first. */
2124static atomic_t kdb_nmi_disabled;
2125
2126static int kdb_disable_nmi(int argc, const char *argv[])
2127{
2128	if (atomic_read(&kdb_nmi_disabled))
2129		return 0;
2130	atomic_set(&kdb_nmi_disabled, 1);
2131	arch_kgdb_ops.enable_nmi(0);
2132	return 0;
2133}
2134
2135static int kdb_param_enable_nmi(const char *val, const struct kernel_param *kp)
2136{
2137	if (!atomic_add_unless(&kdb_nmi_disabled, -1, 0))
2138		return -EINVAL;
2139	arch_kgdb_ops.enable_nmi(1);
2140	return 0;
2141}
2142
2143static const struct kernel_param_ops kdb_param_ops_enable_nmi = {
2144	.set = kdb_param_enable_nmi,
2145};
2146module_param_cb(enable_nmi, &kdb_param_ops_enable_nmi, NULL, 0600);
2147
2148/*
2149 * kdb_cpu - This function implements the 'cpu' command.
2150 *	cpu	[<cpunum>]
2151 * Returns:
2152 *	KDB_CMD_CPU for success, a kdb diagnostic if error
2153 */
2154static void kdb_cpu_status(void)
2155{
2156	int i, start_cpu, first_print = 1;
2157	char state, prev_state = '?';
2158
2159	kdb_printf("Currently on cpu %d\n", raw_smp_processor_id());
2160	kdb_printf("Available cpus: ");
2161	for (start_cpu = -1, i = 0; i < NR_CPUS; i++) {
2162		if (!cpu_online(i)) {
2163			state = 'F';	/* cpu is offline */
2164		} else if (!kgdb_info[i].enter_kgdb) {
2165			state = 'D';	/* cpu is online but unresponsive */
2166		} else {
2167			state = ' ';	/* cpu is responding to kdb */
2168			if (kdb_task_state_char(KDB_TSK(i)) == '-')
2169				state = '-';	/* idle task */
2170		}
2171		if (state != prev_state) {
2172			if (prev_state != '?') {
2173				if (!first_print)
2174					kdb_printf(", ");
2175				first_print = 0;
2176				kdb_printf("%d", start_cpu);
2177				if (start_cpu < i-1)
2178					kdb_printf("-%d", i-1);
2179				if (prev_state != ' ')
2180					kdb_printf("(%c)", prev_state);
2181			}
2182			prev_state = state;
2183			start_cpu = i;
2184		}
2185	}
2186	/* print the trailing cpus, ignoring them if they are all offline */
2187	if (prev_state != 'F') {
2188		if (!first_print)
2189			kdb_printf(", ");
2190		kdb_printf("%d", start_cpu);
2191		if (start_cpu < i-1)
2192			kdb_printf("-%d", i-1);
2193		if (prev_state != ' ')
2194			kdb_printf("(%c)", prev_state);
2195	}
2196	kdb_printf("\n");
2197}
2198
2199static int kdb_cpu(int argc, const char **argv)
2200{
2201	unsigned long cpunum;
2202	int diag;
2203
2204	if (argc == 0) {
2205		kdb_cpu_status();
2206		return 0;
2207	}
2208
2209	if (argc != 1)
2210		return KDB_ARGCOUNT;
2211
2212	diag = kdbgetularg(argv[1], &cpunum);
2213	if (diag)
2214		return diag;
2215
2216	/*
2217	 * Validate cpunum
2218	 */
2219	if ((cpunum >= CONFIG_NR_CPUS) || !kgdb_info[cpunum].enter_kgdb)
2220		return KDB_BADCPUNUM;
2221
2222	dbg_switch_cpu = cpunum;
2223
2224	/*
2225	 * Switch to other cpu
2226	 */
2227	return KDB_CMD_CPU;
2228}
2229
2230/* The user may not realize that ps/bta with no parameters does not print idle
2231 * or sleeping system daemon processes, so tell them how many were suppressed.
2232 */
2233void kdb_ps_suppressed(void)
2234{
2235	int idle = 0, daemon = 0;
 
 
2236	unsigned long cpu;
2237	const struct task_struct *p, *g;
2238	for_each_online_cpu(cpu) {
2239		p = curr_task(cpu);
2240		if (kdb_task_state(p, "-"))
2241			++idle;
2242	}
2243	for_each_process_thread(g, p) {
2244		if (kdb_task_state(p, "ims"))
2245			++daemon;
2246	}
2247	if (idle || daemon) {
2248		if (idle)
2249			kdb_printf("%d idle process%s (state -)%s\n",
2250				   idle, idle == 1 ? "" : "es",
2251				   daemon ? " and " : "");
2252		if (daemon)
2253			kdb_printf("%d sleeping system daemon (state [ims]) "
2254				   "process%s", daemon,
2255				   daemon == 1 ? "" : "es");
2256		kdb_printf(" suppressed,\nuse 'ps A' to see all.\n");
2257	}
2258}
2259
 
 
 
 
 
2260void kdb_ps1(const struct task_struct *p)
2261{
2262	int cpu;
2263	unsigned long tmp;
2264
2265	if (!p ||
2266	    copy_from_kernel_nofault(&tmp, (char *)p, sizeof(unsigned long)))
2267		return;
2268
2269	cpu = kdb_process_cpu(p);
2270	kdb_printf("0x%px %8d %8d  %d %4d   %c  0x%px %c%s\n",
2271		   (void *)p, p->pid, p->parent->pid,
2272		   kdb_task_has_cpu(p), kdb_process_cpu(p),
2273		   kdb_task_state_char(p),
2274		   (void *)(&p->thread),
2275		   p == curr_task(raw_smp_processor_id()) ? '*' : ' ',
2276		   p->comm);
2277	if (kdb_task_has_cpu(p)) {
2278		if (!KDB_TSK(cpu)) {
2279			kdb_printf("  Error: no saved data for this cpu\n");
2280		} else {
2281			if (KDB_TSK(cpu) != p)
2282				kdb_printf("  Error: does not match running "
2283				   "process table (0x%px)\n", KDB_TSK(cpu));
2284		}
2285	}
2286}
2287
2288/*
2289 * kdb_ps - This function implements the 'ps' command which shows a
2290 *	    list of the active processes.
2291 *
2292 * ps [<state_chars>]   Show processes, optionally selecting only those whose
2293 *                      state character is found in <state_chars>.
2294 */
2295static int kdb_ps(int argc, const char **argv)
2296{
2297	struct task_struct *g, *p;
2298	const char *mask;
2299	unsigned long cpu;
2300
2301	if (argc == 0)
2302		kdb_ps_suppressed();
2303	kdb_printf("%-*s      Pid   Parent [*] cpu State %-*s Command\n",
2304		(int)(2*sizeof(void *))+2, "Task Addr",
2305		(int)(2*sizeof(void *))+2, "Thread");
2306	mask = argc ? argv[1] : kdbgetenv("PS");
2307	/* Run the active tasks first */
2308	for_each_online_cpu(cpu) {
2309		if (KDB_FLAG(CMD_INTERRUPT))
2310			return 0;
2311		p = curr_task(cpu);
2312		if (kdb_task_state(p, mask))
2313			kdb_ps1(p);
2314	}
2315	kdb_printf("\n");
2316	/* Now the real tasks */
2317	for_each_process_thread(g, p) {
2318		if (KDB_FLAG(CMD_INTERRUPT))
2319			return 0;
2320		if (kdb_task_state(p, mask))
2321			kdb_ps1(p);
2322	}
2323
2324	return 0;
2325}
2326
2327/*
2328 * kdb_pid - This function implements the 'pid' command which switches
2329 *	the currently active process.
2330 *		pid [<pid> | R]
2331 */
2332static int kdb_pid(int argc, const char **argv)
2333{
2334	struct task_struct *p;
2335	unsigned long val;
2336	int diag;
2337
2338	if (argc > 1)
2339		return KDB_ARGCOUNT;
2340
2341	if (argc) {
2342		if (strcmp(argv[1], "R") == 0) {
2343			p = KDB_TSK(kdb_initial_cpu);
2344		} else {
2345			diag = kdbgetularg(argv[1], &val);
2346			if (diag)
2347				return KDB_BADINT;
2348
2349			p = find_task_by_pid_ns((pid_t)val,	&init_pid_ns);
2350			if (!p) {
2351				kdb_printf("No task with pid=%d\n", (pid_t)val);
2352				return 0;
2353			}
2354		}
2355		kdb_set_current_task(p);
2356	}
2357	kdb_printf("KDB current process is %s(pid=%d)\n",
2358		   kdb_current_task->comm,
2359		   kdb_current_task->pid);
2360
2361	return 0;
2362}
2363
2364static int kdb_kgdb(int argc, const char **argv)
2365{
2366	return KDB_CMD_KGDB;
2367}
2368
2369/*
2370 * kdb_help - This function implements the 'help' and '?' commands.
2371 */
2372static int kdb_help(int argc, const char **argv)
2373{
2374	kdbtab_t *kt;
2375
2376	kdb_printf("%-15.15s %-20.20s %s\n", "Command", "Usage", "Description");
2377	kdb_printf("-----------------------------"
2378		   "-----------------------------\n");
2379	list_for_each_entry(kt, &kdb_cmds_head, list_node) {
2380		char *space = "";
2381		if (KDB_FLAG(CMD_INTERRUPT))
2382			return 0;
2383		if (!kdb_check_flags(kt->flags, kdb_cmd_enabled, true))
2384			continue;
2385		if (strlen(kt->usage) > 20)
2386			space = "\n                                    ";
2387		kdb_printf("%-15.15s %-20s%s%s\n", kt->name,
2388			   kt->usage, space, kt->help);
2389	}
2390	return 0;
2391}
2392
2393/*
2394 * kdb_kill - This function implements the 'kill' commands.
2395 */
2396static int kdb_kill(int argc, const char **argv)
2397{
2398	long sig, pid;
 
2399	struct task_struct *p;
2400
2401	if (argc != 2)
2402		return KDB_ARGCOUNT;
2403
2404	if (kstrtol(argv[1], 0, &sig))
 
2405		return KDB_BADINT;
2406	if ((sig >= 0) || !valid_signal(-sig)) {
2407		kdb_printf("Invalid signal parameter.<-signal>\n");
2408		return 0;
2409	}
2410	sig = -sig;
2411
2412	if (kstrtol(argv[2], 0, &pid))
 
2413		return KDB_BADINT;
2414	if (pid <= 0) {
2415		kdb_printf("Process ID must be large than 0.\n");
2416		return 0;
2417	}
2418
2419	/* Find the process. */
2420	p = find_task_by_pid_ns(pid, &init_pid_ns);
2421	if (!p) {
2422		kdb_printf("The specified process isn't found.\n");
2423		return 0;
2424	}
2425	p = p->group_leader;
2426	kdb_send_sig(p, sig);
2427	return 0;
2428}
2429
2430/*
2431 * Most of this code has been lifted from kernel/timer.c::sys_sysinfo().
2432 * I cannot call that code directly from kdb, it has an unconditional
2433 * cli()/sti() and calls routines that take locks which can stop the debugger.
2434 */
2435static void kdb_sysinfo(struct sysinfo *val)
2436{
2437	u64 uptime = ktime_get_mono_fast_ns();
2438
2439	memset(val, 0, sizeof(*val));
2440	val->uptime = div_u64(uptime, NSEC_PER_SEC);
2441	val->loads[0] = avenrun[0];
2442	val->loads[1] = avenrun[1];
2443	val->loads[2] = avenrun[2];
2444	val->procs = nr_threads-1;
2445	si_meminfo(val);
2446
2447	return;
2448}
2449
2450/*
2451 * kdb_summary - This function implements the 'summary' command.
2452 */
2453static int kdb_summary(int argc, const char **argv)
2454{
2455	time64_t now;
2456	struct sysinfo val;
2457
2458	if (argc)
2459		return KDB_ARGCOUNT;
2460
2461	kdb_printf("sysname    %s\n", init_uts_ns.name.sysname);
2462	kdb_printf("release    %s\n", init_uts_ns.name.release);
2463	kdb_printf("version    %s\n", init_uts_ns.name.version);
2464	kdb_printf("machine    %s\n", init_uts_ns.name.machine);
2465	kdb_printf("nodename   %s\n", init_uts_ns.name.nodename);
2466	kdb_printf("domainname %s\n", init_uts_ns.name.domainname);
2467
2468	now = __ktime_get_real_seconds();
2469	kdb_printf("date       %ptTs tz_minuteswest %d\n", &now, sys_tz.tz_minuteswest);
2470	kdb_sysinfo(&val);
2471	kdb_printf("uptime     ");
2472	if (val.uptime > (24*60*60)) {
2473		int days = val.uptime / (24*60*60);
2474		val.uptime %= (24*60*60);
2475		kdb_printf("%d day%s ", days, str_plural(days));
2476	}
2477	kdb_printf("%02ld:%02ld\n", val.uptime/(60*60), (val.uptime/60)%60);
2478
2479	kdb_printf("load avg   %ld.%02ld %ld.%02ld %ld.%02ld\n",
2480		LOAD_INT(val.loads[0]), LOAD_FRAC(val.loads[0]),
2481		LOAD_INT(val.loads[1]), LOAD_FRAC(val.loads[1]),
2482		LOAD_INT(val.loads[2]), LOAD_FRAC(val.loads[2]));
2483
2484	/* Display in kilobytes */
2485#define K(x) ((x) << (PAGE_SHIFT - 10))
2486	kdb_printf("\nMemTotal:       %8lu kB\nMemFree:        %8lu kB\n"
2487		   "Buffers:        %8lu kB\n",
2488		   K(val.totalram), K(val.freeram), K(val.bufferram));
2489	return 0;
2490}
2491
2492/*
2493 * kdb_per_cpu - This function implements the 'per_cpu' command.
2494 */
2495static int kdb_per_cpu(int argc, const char **argv)
2496{
2497	char fmtstr[64];
2498	int cpu, diag, nextarg = 1;
2499	unsigned long addr, symaddr, val, bytesperword = 0, whichcpu = ~0UL;
2500
2501	if (argc < 1 || argc > 3)
2502		return KDB_ARGCOUNT;
2503
2504	diag = kdbgetaddrarg(argc, argv, &nextarg, &symaddr, NULL, NULL);
2505	if (diag)
2506		return diag;
2507
2508	if (argc >= 2) {
2509		diag = kdbgetularg(argv[2], &bytesperword);
2510		if (diag)
2511			return diag;
2512	}
2513	if (!bytesperword)
2514		bytesperword = KDB_WORD_SIZE;
2515	else if (bytesperword > KDB_WORD_SIZE)
2516		return KDB_BADWIDTH;
2517	sprintf(fmtstr, "%%0%dlx ", (int)(2*bytesperword));
2518	if (argc >= 3) {
2519		diag = kdbgetularg(argv[3], &whichcpu);
2520		if (diag)
2521			return diag;
2522		if (whichcpu >= nr_cpu_ids || !cpu_online(whichcpu)) {
2523			kdb_printf("cpu %ld is not online\n", whichcpu);
2524			return KDB_BADCPUNUM;
2525		}
2526	}
2527
2528	/* Most architectures use __per_cpu_offset[cpu], some use
2529	 * __per_cpu_offset(cpu), smp has no __per_cpu_offset.
2530	 */
2531#ifdef	__per_cpu_offset
2532#define KDB_PCU(cpu) __per_cpu_offset(cpu)
2533#else
2534#ifdef	CONFIG_SMP
2535#define KDB_PCU(cpu) __per_cpu_offset[cpu]
2536#else
2537#define KDB_PCU(cpu) 0
2538#endif
2539#endif
2540	for_each_online_cpu(cpu) {
2541		if (KDB_FLAG(CMD_INTERRUPT))
2542			return 0;
2543
2544		if (whichcpu != ~0UL && whichcpu != cpu)
2545			continue;
2546		addr = symaddr + KDB_PCU(cpu);
2547		diag = kdb_getword(&val, addr, bytesperword);
2548		if (diag) {
2549			kdb_printf("%5d " kdb_bfd_vma_fmt0 " - unable to "
2550				   "read, diag=%d\n", cpu, addr, diag);
2551			continue;
2552		}
2553		kdb_printf("%5d ", cpu);
2554		kdb_md_line(fmtstr, addr,
2555			bytesperword == KDB_WORD_SIZE,
2556			1, bytesperword, 1, 1, 0);
2557	}
2558#undef KDB_PCU
2559	return 0;
2560}
2561
2562/*
2563 * display help for the use of cmd | grep pattern
2564 */
2565static int kdb_grep_help(int argc, const char **argv)
2566{
2567	kdb_printf("Usage of  cmd args | grep pattern:\n");
2568	kdb_printf("  Any command's output may be filtered through an ");
2569	kdb_printf("emulated 'pipe'.\n");
2570	kdb_printf("  'grep' is just a key word.\n");
2571	kdb_printf("  The pattern may include a very limited set of "
2572		   "metacharacters:\n");
2573	kdb_printf("   pattern or ^pattern or pattern$ or ^pattern$\n");
2574	kdb_printf("  And if there are spaces in the pattern, you may "
2575		   "quote it:\n");
2576	kdb_printf("   \"pat tern\" or \"^pat tern\" or \"pat tern$\""
2577		   " or \"^pat tern$\"\n");
2578	return 0;
2579}
2580
2581/**
2582 * kdb_register() - This function is used to register a kernel debugger
2583 *                  command.
2584 * @cmd: pointer to kdb command
2585 *
2586 * Note that it's the job of the caller to keep the memory for the cmd
2587 * allocated until unregister is called.
 
 
 
 
2588 */
2589int kdb_register(kdbtab_t *cmd)
 
 
 
 
 
2590{
2591	kdbtab_t *kp;
2592
2593	list_for_each_entry(kp, &kdb_cmds_head, list_node) {
2594		if (strcmp(kp->name, cmd->name) == 0) {
2595			kdb_printf("Duplicate kdb cmd: %s, func %p help %s\n",
2596				   cmd->name, cmd->func, cmd->help);
2597			return 1;
2598		}
2599	}
2600
2601	list_add_tail(&cmd->list_node, &kdb_cmds_head);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2602	return 0;
2603}
2604EXPORT_SYMBOL_GPL(kdb_register);
2605
2606/**
2607 * kdb_register_table() - This function is used to register a kdb command
2608 *                        table.
2609 * @kp: pointer to kdb command table
2610 * @len: length of kdb command table
2611 */
2612void kdb_register_table(kdbtab_t *kp, size_t len)
2613{
2614	while (len--) {
2615		list_add_tail(&kp->list_node, &kdb_cmds_head);
2616		kp++;
2617	}
2618}
2619
2620/**
2621 * kdb_unregister() - This function is used to unregister a kernel debugger
2622 *                    command. It is generally called when a module which
2623 *                    implements kdb command is unloaded.
2624 * @cmd: pointer to kdb command
 
 
 
 
 
 
2625 */
2626void kdb_unregister(kdbtab_t *cmd)
 
 
 
 
2627{
2628	list_del(&cmd->list_node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2629}
2630EXPORT_SYMBOL_GPL(kdb_unregister);
2631
2632static kdbtab_t maintab[] = {
2633	{	.name = "md",
2634		.func = kdb_md,
2635		.usage = "<vaddr>",
2636		.help = "Display Memory Contents, also mdWcN, e.g. md8c1",
2637		.minlen = 1,
2638		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2639	},
2640	{	.name = "mdr",
2641		.func = kdb_md,
2642		.usage = "<vaddr> <bytes>",
2643		.help = "Display Raw Memory",
2644		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2645	},
2646	{	.name = "mdp",
2647		.func = kdb_md,
2648		.usage = "<paddr> <bytes>",
2649		.help = "Display Physical Memory",
2650		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2651	},
2652	{	.name = "mds",
2653		.func = kdb_md,
2654		.usage = "<vaddr>",
2655		.help = "Display Memory Symbolically",
2656		.flags = KDB_ENABLE_MEM_READ | KDB_REPEAT_NO_ARGS,
2657	},
2658	{	.name = "mm",
2659		.func = kdb_mm,
2660		.usage = "<vaddr> <contents>",
2661		.help = "Modify Memory Contents",
2662		.flags = KDB_ENABLE_MEM_WRITE | KDB_REPEAT_NO_ARGS,
2663	},
2664	{	.name = "go",
2665		.func = kdb_go,
2666		.usage = "[<vaddr>]",
2667		.help = "Continue Execution",
2668		.minlen = 1,
2669		.flags = KDB_ENABLE_REG_WRITE |
2670			     KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2671	},
2672	{	.name = "rd",
2673		.func = kdb_rd,
2674		.usage = "",
2675		.help = "Display Registers",
2676		.flags = KDB_ENABLE_REG_READ,
2677	},
2678	{	.name = "rm",
2679		.func = kdb_rm,
2680		.usage = "<reg> <contents>",
2681		.help = "Modify Registers",
2682		.flags = KDB_ENABLE_REG_WRITE,
2683	},
2684	{	.name = "ef",
2685		.func = kdb_ef,
2686		.usage = "<vaddr>",
2687		.help = "Display exception frame",
2688		.flags = KDB_ENABLE_MEM_READ,
2689	},
2690	{	.name = "bt",
2691		.func = kdb_bt,
2692		.usage = "[<vaddr>]",
2693		.help = "Stack traceback",
2694		.minlen = 1,
2695		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2696	},
2697	{	.name = "btp",
2698		.func = kdb_bt,
2699		.usage = "<pid>",
2700		.help = "Display stack for process <pid>",
2701		.flags = KDB_ENABLE_INSPECT,
2702	},
2703	{	.name = "bta",
2704		.func = kdb_bt,
2705		.usage = "[<state_chars>|A]",
2706		.help = "Backtrace all processes whose state matches",
2707		.flags = KDB_ENABLE_INSPECT,
2708	},
2709	{	.name = "btc",
2710		.func = kdb_bt,
2711		.usage = "",
2712		.help = "Backtrace current process on each cpu",
2713		.flags = KDB_ENABLE_INSPECT,
2714	},
2715	{	.name = "btt",
2716		.func = kdb_bt,
2717		.usage = "<vaddr>",
2718		.help = "Backtrace process given its struct task address",
2719		.flags = KDB_ENABLE_MEM_READ | KDB_ENABLE_INSPECT_NO_ARGS,
2720	},
2721	{	.name = "env",
2722		.func = kdb_env,
2723		.usage = "",
2724		.help = "Show environment variables",
2725		.flags = KDB_ENABLE_ALWAYS_SAFE,
2726	},
2727	{	.name = "set",
2728		.func = kdb_set,
2729		.usage = "",
2730		.help = "Set environment variables",
2731		.flags = KDB_ENABLE_ALWAYS_SAFE,
2732	},
2733	{	.name = "help",
2734		.func = kdb_help,
2735		.usage = "",
2736		.help = "Display Help Message",
2737		.minlen = 1,
2738		.flags = KDB_ENABLE_ALWAYS_SAFE,
2739	},
2740	{	.name = "?",
2741		.func = kdb_help,
2742		.usage = "",
2743		.help = "Display Help Message",
2744		.flags = KDB_ENABLE_ALWAYS_SAFE,
2745	},
2746	{	.name = "cpu",
2747		.func = kdb_cpu,
2748		.usage = "<cpunum>",
2749		.help = "Switch to new cpu",
2750		.flags = KDB_ENABLE_ALWAYS_SAFE_NO_ARGS,
2751	},
2752	{	.name = "kgdb",
2753		.func = kdb_kgdb,
2754		.usage = "",
2755		.help = "Enter kgdb mode",
2756		.flags = 0,
2757	},
2758	{	.name = "ps",
2759		.func = kdb_ps,
2760		.usage = "[<state_chars>|A]",
2761		.help = "Display active task list",
2762		.flags = KDB_ENABLE_INSPECT,
2763	},
2764	{	.name = "pid",
2765		.func = kdb_pid,
2766		.usage = "<pidnum>",
2767		.help = "Switch to another task",
2768		.flags = KDB_ENABLE_INSPECT,
2769	},
2770	{	.name = "reboot",
2771		.func = kdb_reboot,
2772		.usage = "",
2773		.help = "Reboot the machine immediately",
2774		.flags = KDB_ENABLE_REBOOT,
2775	},
2776#if defined(CONFIG_MODULES)
2777	{	.name = "lsmod",
2778		.func = kdb_lsmod,
2779		.usage = "",
2780		.help = "List loaded kernel modules",
2781		.flags = KDB_ENABLE_INSPECT,
2782	},
2783#endif
2784#if defined(CONFIG_MAGIC_SYSRQ)
2785	{	.name = "sr",
2786		.func = kdb_sr,
2787		.usage = "<key>",
2788		.help = "Magic SysRq key",
2789		.flags = KDB_ENABLE_ALWAYS_SAFE,
2790	},
2791#endif
2792#if defined(CONFIG_PRINTK)
2793	{	.name = "dmesg",
2794		.func = kdb_dmesg,
2795		.usage = "[lines]",
2796		.help = "Display syslog buffer",
2797		.flags = KDB_ENABLE_ALWAYS_SAFE,
2798	},
2799#endif
2800	{	.name = "defcmd",
2801		.func = kdb_defcmd,
2802		.usage = "name \"usage\" \"help\"",
2803		.help = "Define a set of commands, down to endefcmd",
2804		/*
2805		 * Macros are always safe because when executed each
2806		 * internal command re-enters kdb_parse() and is safety
2807		 * checked individually.
2808		 */
2809		.flags = KDB_ENABLE_ALWAYS_SAFE,
2810	},
2811	{	.name = "kill",
2812		.func = kdb_kill,
2813		.usage = "<-signal> <pid>",
2814		.help = "Send a signal to a process",
2815		.flags = KDB_ENABLE_SIGNAL,
2816	},
2817	{	.name = "summary",
2818		.func = kdb_summary,
2819		.usage = "",
2820		.help = "Summarize the system",
2821		.minlen = 4,
2822		.flags = KDB_ENABLE_ALWAYS_SAFE,
2823	},
2824	{	.name = "per_cpu",
2825		.func = kdb_per_cpu,
2826		.usage = "<sym> [<bytes>] [<cpu>]",
2827		.help = "Display per_cpu variables",
2828		.minlen = 3,
2829		.flags = KDB_ENABLE_MEM_READ,
2830	},
2831	{	.name = "grephelp",
2832		.func = kdb_grep_help,
2833		.usage = "",
2834		.help = "Display help on | grep",
2835		.flags = KDB_ENABLE_ALWAYS_SAFE,
2836	},
2837};
2838
2839static kdbtab_t nmicmd = {
2840	.name = "disable_nmi",
2841	.func = kdb_disable_nmi,
2842	.usage = "",
2843	.help = "Disable NMI entry to KDB",
2844	.flags = KDB_ENABLE_ALWAYS_SAFE,
2845};
2846
2847/* Initialize the kdb command table. */
2848static void __init kdb_inittab(void)
2849{
2850	kdb_register_table(maintab, ARRAY_SIZE(maintab));
2851	if (arch_kgdb_ops.enable_nmi)
2852		kdb_register_table(&nmicmd, 1);
2853}
2854
2855/* Execute any commands defined in kdb_cmds.  */
2856static void __init kdb_cmd_init(void)
2857{
2858	int i, diag;
2859	for (i = 0; kdb_cmds[i]; ++i) {
2860		diag = kdb_parse(kdb_cmds[i]);
2861		if (diag)
2862			kdb_printf("kdb command %s failed, kdb diag %d\n",
2863				kdb_cmds[i], diag);
2864	}
2865	if (defcmd_in_progress) {
2866		kdb_printf("Incomplete 'defcmd' set, forcing endefcmd\n");
2867		kdb_parse("endefcmd");
2868	}
2869}
2870
2871/* Initialize kdb_printf, breakpoint tables and kdb state */
2872void __init kdb_init(int lvl)
2873{
2874	static int kdb_init_lvl = KDB_NOT_INITIALIZED;
2875	int i;
2876
2877	if (kdb_init_lvl == KDB_INIT_FULL || lvl <= kdb_init_lvl)
2878		return;
2879	for (i = kdb_init_lvl; i < lvl; i++) {
2880		switch (i) {
2881		case KDB_NOT_INITIALIZED:
2882			kdb_inittab();		/* Initialize Command Table */
2883			kdb_initbptab();	/* Initialize Breakpoints */
2884			break;
2885		case KDB_INIT_EARLY:
2886			kdb_cmd_init();		/* Build kdb_cmds tables */
2887			break;
2888		}
2889	}
2890	kdb_init_lvl = lvl;
2891}