1// SPDX-License-Identifier: GPL-2.0
   2#include <dirent.h>
   3#include <errno.h>
   4#include <stdlib.h>
   5#include <stdio.h>
   6#include <string.h>
   7#include <linux/capability.h>
   8#include <linux/kernel.h>
   9#include <linux/mman.h>
  10#include <linux/string.h>
  11#include <linux/time64.h>
  12#include <sys/types.h>
  13#include <sys/stat.h>
  14#include <sys/param.h>
  15#include <fcntl.h>
  16#include <unistd.h>
  17#include <inttypes.h>
  18#include "annotate.h"
  19#include "build-id.h"
  20#include "cap.h"
  21#include "dso.h"
  22#include "util.h" // lsdir()
  23#include "debug.h"
  24#include "event.h"
  25#include "machine.h"
  26#include "map.h"
  27#include "symbol.h"
  28#include "map_symbol.h"
  29#include "mem-events.h"
 
  30#include "symsrc.h"
  31#include "strlist.h"
  32#include "intlist.h"
  33#include "namespaces.h"
  34#include "header.h"
  35#include "path.h"
  36#include <linux/ctype.h>
  37#include <linux/zalloc.h>
  38
  39#include <elf.h>
  40#include <limits.h>
  41#include <symbol/kallsyms.h>
  42#include <sys/utsname.h>
  43
  44static int dso__load_kernel_sym(struct dso *dso, struct map *map);
  45static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
  46static bool symbol__is_idle(const char *name);
  47
  48int vmlinux_path__nr_entries;
  49char **vmlinux_path;
  50
  51struct symbol_conf symbol_conf = {
  52	.nanosecs		= false,
  53	.use_modules		= true,
  54	.try_vmlinux_path	= true,
  55	.demangle		= true,
  56	.demangle_kernel	= false,
  57	.cumulate_callchain	= true,
  58	.time_quantum		= 100 * NSEC_PER_MSEC, /* 100ms */
  59	.show_hist_headers	= true,
  60	.symfs			= "",
  61	.event_group		= true,
  62	.inline_name		= true,
  63	.res_sample		= 0,
  64};
  65
 
 
 
 
 
 
 
 
 
 
  66static enum dso_binary_type binary_type_symtab[] = {
  67	DSO_BINARY_TYPE__KALLSYMS,
  68	DSO_BINARY_TYPE__GUEST_KALLSYMS,
  69	DSO_BINARY_TYPE__JAVA_JIT,
  70	DSO_BINARY_TYPE__DEBUGLINK,
  71	DSO_BINARY_TYPE__BUILD_ID_CACHE,
  72	DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
  73	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  74	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  75	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  76	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  77	DSO_BINARY_TYPE__GUEST_KMODULE,
  78	DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  79	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  80	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  81	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  82	DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
  83	DSO_BINARY_TYPE__NOT_FOUND,
  84};
  85
  86#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  87
  88static bool symbol_type__filter(char symbol_type)
  89{
  90	symbol_type = toupper(symbol_type);
  91	return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B';
  92}
  93
  94static int prefix_underscores_count(const char *str)
  95{
  96	const char *tail = str;
  97
  98	while (*tail == '_')
  99		tail++;
 100
 101	return tail - str;
 102}
 103
 104const char * __weak arch__normalize_symbol_name(const char *name)
 105{
 106	return name;
 107}
 108
 109int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
 110{
 111	return strcmp(namea, nameb);
 112}
 113
 114int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
 115					unsigned int n)
 116{
 117	return strncmp(namea, nameb, n);
 118}
 119
 120int __weak arch__choose_best_symbol(struct symbol *syma,
 121				    struct symbol *symb __maybe_unused)
 122{
 123	/* Avoid "SyS" kernel syscall aliases */
 124	if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
 125		return SYMBOL_B;
 126	if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
 127		return SYMBOL_B;
 128
 129	return SYMBOL_A;
 130}
 131
 132static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 133{
 134	s64 a;
 135	s64 b;
 136	size_t na, nb;
 137
 138	/* Prefer a symbol with non zero length */
 139	a = syma->end - syma->start;
 140	b = symb->end - symb->start;
 141	if ((b == 0) && (a > 0))
 142		return SYMBOL_A;
 143	else if ((a == 0) && (b > 0))
 144		return SYMBOL_B;
 145
 
 
 
 
 
 
 
 146	/* Prefer a non weak symbol over a weak one */
 147	a = syma->binding == STB_WEAK;
 148	b = symb->binding == STB_WEAK;
 149	if (b && !a)
 150		return SYMBOL_A;
 151	if (a && !b)
 152		return SYMBOL_B;
 153
 154	/* Prefer a global symbol over a non global one */
 155	a = syma->binding == STB_GLOBAL;
 156	b = symb->binding == STB_GLOBAL;
 157	if (a && !b)
 158		return SYMBOL_A;
 159	if (b && !a)
 160		return SYMBOL_B;
 161
 162	/* Prefer a symbol with less underscores */
 163	a = prefix_underscores_count(syma->name);
 164	b = prefix_underscores_count(symb->name);
 165	if (b > a)
 166		return SYMBOL_A;
 167	else if (a > b)
 168		return SYMBOL_B;
 169
 170	/* Choose the symbol with the longest name */
 171	na = strlen(syma->name);
 172	nb = strlen(symb->name);
 173	if (na > nb)
 174		return SYMBOL_A;
 175	else if (na < nb)
 176		return SYMBOL_B;
 177
 178	return arch__choose_best_symbol(syma, symb);
 179}
 180
 181void symbols__fixup_duplicate(struct rb_root_cached *symbols)
 182{
 183	struct rb_node *nd;
 184	struct symbol *curr, *next;
 185
 186	if (symbol_conf.allow_aliases)
 187		return;
 188
 189	nd = rb_first_cached(symbols);
 190
 191	while (nd) {
 192		curr = rb_entry(nd, struct symbol, rb_node);
 193again:
 194		nd = rb_next(&curr->rb_node);
 195		next = rb_entry(nd, struct symbol, rb_node);
 196
 197		if (!nd)
 198			break;
 199
 
 200		if (curr->start != next->start)
 201			continue;
 202
 203		if (choose_best_symbol(curr, next) == SYMBOL_A) {
 
 
 204			rb_erase_cached(&next->rb_node, symbols);
 205			symbol__delete(next);
 206			goto again;
 207		} else {
 
 
 208			nd = rb_next(&curr->rb_node);
 209			rb_erase_cached(&curr->rb_node, symbols);
 210			symbol__delete(curr);
 211		}
 212	}
 213}
 214
 215/* Update zero-sized symbols using the address of the next symbol */
 216void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
 217{
 218	struct rb_node *nd, *prevnd = rb_first_cached(symbols);
 219	struct symbol *curr, *prev;
 220
 221	if (prevnd == NULL)
 222		return;
 223
 224	curr = rb_entry(prevnd, struct symbol, rb_node);
 225
 226	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 227		prev = curr;
 228		curr = rb_entry(nd, struct symbol, rb_node);
 229
 230		/*
 231		 * On some architecture kernel text segment start is located at
 232		 * some low memory address, while modules are located at high
 233		 * memory addresses (or vice versa).  The gap between end of
 234		 * kernel text segment and beginning of first module's text
 235		 * segment is very big.  Therefore do not fill this gap and do
 236		 * not assign it to the kernel dso map (kallsyms).
 237		 *
 
 
 
 
 238		 * In kallsyms, it determines module symbols using '[' character
 239		 * like in:
 240		 *   ffffffffc1937000 T hdmi_driver_init  [snd_hda_codec_hdmi]
 241		 */
 242		if (prev->end == prev->start) {
 
 
 
 
 
 
 
 
 
 
 
 243			/* Last kernel/module symbol mapped to end of page */
 244			if (is_kallsyms && (!strchr(prev->name, '[') !=
 245					    !strchr(curr->name, '[')))
 
 
 246				prev->end = roundup(prev->end + 4096, 4096);
 247			else
 248				prev->end = curr->start;
 249
 250			pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
 251				  __func__, prev->name, prev->end);
 252		}
 253	}
 254
 255	/* Last entry */
 256	if (curr->end == curr->start)
 257		curr->end = roundup(curr->start, 4096) + 4096;
 258}
 259
 260void maps__fixup_end(struct maps *maps)
 261{
 262	struct map *prev = NULL, *curr;
 263
 264	down_write(&maps->lock);
 265
 266	maps__for_each_entry(maps, curr) {
 267		if (prev != NULL && !prev->end)
 268			prev->end = curr->start;
 269
 270		prev = curr;
 271	}
 272
 273	/*
 274	 * We still haven't the actual symbols, so guess the
 275	 * last map final address.
 276	 */
 277	if (curr && !curr->end)
 278		curr->end = ~0ULL;
 279
 280	up_write(&maps->lock);
 281}
 282
 283struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
 284{
 285	size_t namelen = strlen(name) + 1;
 286	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 287					sizeof(*sym) + namelen));
 288	if (sym == NULL)
 289		return NULL;
 290
 291	if (symbol_conf.priv_size) {
 292		if (symbol_conf.init_annotation) {
 293			struct annotation *notes = (void *)sym;
 294			annotation__init(notes);
 295		}
 296		sym = ((void *)sym) + symbol_conf.priv_size;
 297	}
 298
 299	sym->start   = start;
 300	sym->end     = len ? start + len : start;
 301	sym->type    = type;
 302	sym->binding = binding;
 303	sym->namelen = namelen - 1;
 304
 305	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 306		  __func__, name, start, sym->end);
 307	memcpy(sym->name, name, namelen);
 308
 309	return sym;
 310}
 311
 312void symbol__delete(struct symbol *sym)
 313{
 314	if (symbol_conf.priv_size) {
 315		if (symbol_conf.init_annotation) {
 316			struct annotation *notes = symbol__annotation(sym);
 317
 318			annotation__exit(notes);
 319		}
 320	}
 321	free(((void *)sym) - symbol_conf.priv_size);
 322}
 323
 324void symbols__delete(struct rb_root_cached *symbols)
 325{
 326	struct symbol *pos;
 327	struct rb_node *next = rb_first_cached(symbols);
 328
 329	while (next) {
 330		pos = rb_entry(next, struct symbol, rb_node);
 331		next = rb_next(&pos->rb_node);
 332		rb_erase_cached(&pos->rb_node, symbols);
 333		symbol__delete(pos);
 334	}
 335}
 336
 337void __symbols__insert(struct rb_root_cached *symbols,
 338		       struct symbol *sym, bool kernel)
 339{
 340	struct rb_node **p = &symbols->rb_root.rb_node;
 341	struct rb_node *parent = NULL;
 342	const u64 ip = sym->start;
 343	struct symbol *s;
 344	bool leftmost = true;
 345
 346	if (kernel) {
 347		const char *name = sym->name;
 348		/*
 349		 * ppc64 uses function descriptors and appends a '.' to the
 350		 * start of every instruction address. Remove it.
 351		 */
 352		if (name[0] == '.')
 353			name++;
 354		sym->idle = symbol__is_idle(name);
 355	}
 356
 357	while (*p != NULL) {
 358		parent = *p;
 359		s = rb_entry(parent, struct symbol, rb_node);
 360		if (ip < s->start)
 361			p = &(*p)->rb_left;
 362		else {
 363			p = &(*p)->rb_right;
 364			leftmost = false;
 365		}
 366	}
 367	rb_link_node(&sym->rb_node, parent, p);
 368	rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
 369}
 370
 371void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
 372{
 373	__symbols__insert(symbols, sym, false);
 374}
 375
 376static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
 377{
 378	struct rb_node *n;
 379
 380	if (symbols == NULL)
 381		return NULL;
 382
 383	n = symbols->rb_root.rb_node;
 384
 385	while (n) {
 386		struct symbol *s = rb_entry(n, struct symbol, rb_node);
 387
 388		if (ip < s->start)
 389			n = n->rb_left;
 390		else if (ip > s->end || (ip == s->end && ip != s->start))
 391			n = n->rb_right;
 392		else
 393			return s;
 394	}
 395
 396	return NULL;
 397}
 398
 399static struct symbol *symbols__first(struct rb_root_cached *symbols)
 400{
 401	struct rb_node *n = rb_first_cached(symbols);
 402
 403	if (n)
 404		return rb_entry(n, struct symbol, rb_node);
 405
 406	return NULL;
 407}
 408
 409static struct symbol *symbols__last(struct rb_root_cached *symbols)
 410{
 411	struct rb_node *n = rb_last(&symbols->rb_root);
 412
 413	if (n)
 414		return rb_entry(n, struct symbol, rb_node);
 415
 416	return NULL;
 417}
 418
 419static struct symbol *symbols__next(struct symbol *sym)
 420{
 421	struct rb_node *n = rb_next(&sym->rb_node);
 422
 423	if (n)
 424		return rb_entry(n, struct symbol, rb_node);
 425
 426	return NULL;
 427}
 428
 429static void symbols__insert_by_name(struct rb_root_cached *symbols, struct symbol *sym)
 430{
 431	struct rb_node **p = &symbols->rb_root.rb_node;
 432	struct rb_node *parent = NULL;
 433	struct symbol_name_rb_node *symn, *s;
 434	bool leftmost = true;
 435
 436	symn = container_of(sym, struct symbol_name_rb_node, sym);
 437
 438	while (*p != NULL) {
 439		parent = *p;
 440		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 441		if (strcmp(sym->name, s->sym.name) < 0)
 442			p = &(*p)->rb_left;
 443		else {
 444			p = &(*p)->rb_right;
 445			leftmost = false;
 446		}
 447	}
 448	rb_link_node(&symn->rb_node, parent, p);
 449	rb_insert_color_cached(&symn->rb_node, symbols, leftmost);
 450}
 451
 452static void symbols__sort_by_name(struct rb_root_cached *symbols,
 453				  struct rb_root_cached *source)
 454{
 455	struct rb_node *nd;
 
 
 
 
 
 
 
 
 
 456
 457	for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
 458		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 459		symbols__insert_by_name(symbols, pos);
 
 460	}
 
 
 
 461}
 462
 463int symbol__match_symbol_name(const char *name, const char *str,
 464			      enum symbol_tag_include includes)
 465{
 466	const char *versioning;
 467
 468	if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
 469	    (versioning = strstr(name, "@@"))) {
 470		int len = strlen(str);
 471
 472		if (len < versioning - name)
 473			len = versioning - name;
 474
 475		return arch__compare_symbol_names_n(name, str, len);
 476	} else
 477		return arch__compare_symbol_names(name, str);
 478}
 479
 480static struct symbol *symbols__find_by_name(struct rb_root_cached *symbols,
 
 481					    const char *name,
 482					    enum symbol_tag_include includes)
 
 483{
 484	struct rb_node *n;
 485	struct symbol_name_rb_node *s = NULL;
 486
 487	if (symbols == NULL)
 488		return NULL;
 489
 490	n = symbols->rb_root.rb_node;
 
 491
 492	while (n) {
 493		int cmp;
 494
 495		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 496		cmp = symbol__match_symbol_name(s->sym.name, name, includes);
 497
 498		if (cmp > 0)
 499			n = n->rb_left;
 500		else if (cmp < 0)
 501			n = n->rb_right;
 502		else
 
 
 
 503			break;
 
 504	}
 505
 506	if (n == NULL)
 507		return NULL;
 508
 509	if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY)
 510		/* return first symbol that has same name (if any) */
 511		for (n = rb_prev(n); n; n = rb_prev(n)) {
 512			struct symbol_name_rb_node *tmp;
 513
 514			tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
 515			if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
 
 
 
 516				break;
 517
 518			s = tmp;
 519		}
 520
 521	return &s->sym;
 
 522}
 523
 524void dso__reset_find_symbol_cache(struct dso *dso)
 525{
 526	dso->last_find_result.addr   = 0;
 527	dso->last_find_result.symbol = NULL;
 528}
 529
 530void dso__insert_symbol(struct dso *dso, struct symbol *sym)
 531{
 532	__symbols__insert(&dso->symbols, sym, dso->kernel);
 533
 534	/* update the symbol cache if necessary */
 535	if (dso->last_find_result.addr >= sym->start &&
 536	    (dso->last_find_result.addr < sym->end ||
 537	    sym->start == sym->end)) {
 538		dso->last_find_result.symbol = sym;
 539	}
 540}
 541
 542void dso__delete_symbol(struct dso *dso, struct symbol *sym)
 543{
 544	rb_erase_cached(&sym->rb_node, &dso->symbols);
 545	symbol__delete(sym);
 546	dso__reset_find_symbol_cache(dso);
 547}
 548
 549struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
 550{
 551	if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
 552		dso->last_find_result.addr   = addr;
 553		dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
 554	}
 555
 556	return dso->last_find_result.symbol;
 
 
 
 
 
 557}
 558
 559struct symbol *dso__first_symbol(struct dso *dso)
 560{
 561	return symbols__first(&dso->symbols);
 562}
 563
 564struct symbol *dso__last_symbol(struct dso *dso)
 565{
 566	return symbols__last(&dso->symbols);
 567}
 568
 569struct symbol *dso__next_symbol(struct symbol *sym)
 570{
 571	return symbols__next(sym);
 572}
 573
 574struct symbol *symbol__next_by_name(struct symbol *sym)
 575{
 576	struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
 577	struct rb_node *n = rb_next(&s->rb_node);
 578
 579	return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
 
 580}
 581
 582 /*
 583  * Returns first symbol that matched with @name.
 584  */
 585struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name)
 586{
 587	struct symbol *s = symbols__find_by_name(&dso->symbol_names, name,
 588						 SYMBOL_TAG_INCLUDE__NONE);
 589	if (!s)
 590		s = symbols__find_by_name(&dso->symbol_names, name,
 591					  SYMBOL_TAG_INCLUDE__DEFAULT_ONLY);
 
 
 592	return s;
 593}
 594
 595void dso__sort_by_name(struct dso *dso)
 596{
 597	dso__set_sorted_by_name(dso);
 598	return symbols__sort_by_name(&dso->symbol_names, &dso->symbols);
 
 
 
 
 
 
 
 
 
 599}
 600
 601/*
 602 * While we find nice hex chars, build a long_val.
 603 * Return number of chars processed.
 604 */
 605static int hex2u64(const char *ptr, u64 *long_val)
 606{
 607	char *p;
 608
 609	*long_val = strtoull(ptr, &p, 16);
 610
 611	return p - ptr;
 612}
 613
 614
 615int modules__parse(const char *filename, void *arg,
 616		   int (*process_module)(void *arg, const char *name,
 617					 u64 start, u64 size))
 618{
 619	char *line = NULL;
 620	size_t n;
 621	FILE *file;
 622	int err = 0;
 623
 624	file = fopen(filename, "r");
 625	if (file == NULL)
 626		return -1;
 627
 628	while (1) {
 629		char name[PATH_MAX];
 630		u64 start, size;
 631		char *sep, *endptr;
 632		ssize_t line_len;
 633
 634		line_len = getline(&line, &n, file);
 635		if (line_len < 0) {
 636			if (feof(file))
 637				break;
 638			err = -1;
 639			goto out;
 640		}
 641
 642		if (!line) {
 643			err = -1;
 644			goto out;
 645		}
 646
 647		line[--line_len] = '\0'; /* \n */
 648
 649		sep = strrchr(line, 'x');
 650		if (sep == NULL)
 651			continue;
 652
 653		hex2u64(sep + 1, &start);
 654
 655		sep = strchr(line, ' ');
 656		if (sep == NULL)
 657			continue;
 658
 659		*sep = '\0';
 660
 661		scnprintf(name, sizeof(name), "[%s]", line);
 662
 663		size = strtoul(sep + 1, &endptr, 0);
 664		if (*endptr != ' ' && *endptr != '\t')
 665			continue;
 666
 667		err = process_module(arg, name, start, size);
 668		if (err)
 669			break;
 670	}
 671out:
 672	free(line);
 673	fclose(file);
 674	return err;
 675}
 676
 677/*
 678 * These are symbols in the kernel image, so make sure that
 679 * sym is from a kernel DSO.
 680 */
 681static bool symbol__is_idle(const char *name)
 682{
 683	const char * const idle_symbols[] = {
 684		"acpi_idle_do_entry",
 685		"acpi_processor_ffh_cstate_enter",
 686		"arch_cpu_idle",
 687		"cpu_idle",
 688		"cpu_startup_entry",
 689		"idle_cpu",
 690		"intel_idle",
 
 691		"default_idle",
 692		"native_safe_halt",
 693		"enter_idle",
 694		"exit_idle",
 695		"mwait_idle",
 696		"mwait_idle_with_hints",
 697		"mwait_idle_with_hints.constprop.0",
 698		"poll_idle",
 699		"ppc64_runlatch_off",
 700		"pseries_dedicated_idle_sleep",
 701		"psw_idle",
 702		"psw_idle_exit",
 703		NULL
 704	};
 705	int i;
 706	static struct strlist *idle_symbols_list;
 707
 708	if (idle_symbols_list)
 709		return strlist__has_entry(idle_symbols_list, name);
 710
 711	idle_symbols_list = strlist__new(NULL, NULL);
 712
 713	for (i = 0; idle_symbols[i]; i++)
 714		strlist__add(idle_symbols_list, idle_symbols[i]);
 715
 716	return strlist__has_entry(idle_symbols_list, name);
 717}
 718
 719static int map__process_kallsym_symbol(void *arg, const char *name,
 720				       char type, u64 start)
 721{
 722	struct symbol *sym;
 723	struct dso *dso = arg;
 724	struct rb_root_cached *root = &dso->symbols;
 725
 726	if (!symbol_type__filter(type))
 727		return 0;
 728
 729	/* Ignore local symbols for ARM modules */
 730	if (name[0] == '$')
 731		return 0;
 732
 733	/*
 734	 * module symbols are not sorted so we add all
 735	 * symbols, setting length to 0, and rely on
 736	 * symbols__fixup_end() to fix it up.
 737	 */
 738	sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
 739	if (sym == NULL)
 740		return -ENOMEM;
 741	/*
 742	 * We will pass the symbols to the filter later, in
 743	 * map__split_kallsyms, when we have split the maps per module
 744	 */
 745	__symbols__insert(root, sym, !strchr(name, '['));
 746
 747	return 0;
 748}
 749
 750/*
 751 * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 752 * so that we can in the next step set the symbol ->end address and then
 753 * call kernel_maps__split_kallsyms.
 754 */
 755static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
 756{
 757	return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
 758}
 759
 760static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
 761{
 762	struct map *curr_map;
 763	struct symbol *pos;
 764	int count = 0;
 765	struct rb_root_cached old_root = dso->symbols;
 766	struct rb_root_cached *root = &dso->symbols;
 767	struct rb_node *next = rb_first_cached(root);
 768
 769	if (!kmaps)
 770		return -1;
 771
 772	*root = RB_ROOT_CACHED;
 773
 774	while (next) {
 
 
 775		char *module;
 776
 777		pos = rb_entry(next, struct symbol, rb_node);
 778		next = rb_next(&pos->rb_node);
 779
 780		rb_erase_cached(&pos->rb_node, &old_root);
 781		RB_CLEAR_NODE(&pos->rb_node);
 782		module = strchr(pos->name, '\t');
 783		if (module)
 784			*module = '\0';
 785
 786		curr_map = maps__find(kmaps, pos->start);
 787
 788		if (!curr_map) {
 789			symbol__delete(pos);
 790			continue;
 791		}
 792
 793		pos->start -= curr_map->start - curr_map->pgoff;
 794		if (pos->end > curr_map->end)
 795			pos->end = curr_map->end;
 796		if (pos->end)
 797			pos->end -= curr_map->start - curr_map->pgoff;
 798		symbols__insert(&curr_map->dso->symbols, pos);
 799		++count;
 
 800	}
 801
 802	/* Symbols have been adjusted */
 803	dso->adjust_symbols = 1;
 804
 805	return count;
 806}
 807
 808/*
 809 * Split the symbols into maps, making sure there are no overlaps, i.e. the
 810 * kernel range is broken in several maps, named [kernel].N, as we don't have
 811 * the original ELF section names vmlinux have.
 812 */
 813static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 814				struct map *initial_map)
 815{
 816	struct machine *machine;
 817	struct map *curr_map = initial_map;
 818	struct symbol *pos;
 819	int count = 0, moved = 0;
 820	struct rb_root_cached *root = &dso->symbols;
 821	struct rb_node *next = rb_first_cached(root);
 822	int kernel_range = 0;
 823	bool x86_64;
 824
 825	if (!kmaps)
 826		return -1;
 827
 828	machine = kmaps->machine;
 829
 830	x86_64 = machine__is(machine, "x86_64");
 831
 832	while (next) {
 833		char *module;
 834
 835		pos = rb_entry(next, struct symbol, rb_node);
 836		next = rb_next(&pos->rb_node);
 837
 838		module = strchr(pos->name, '\t');
 839		if (module) {
 
 
 840			if (!symbol_conf.use_modules)
 841				goto discard_symbol;
 842
 843			*module++ = '\0';
 844
 845			if (strcmp(curr_map->dso->short_name, module)) {
 846				if (curr_map != initial_map &&
 847				    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 848				    machine__is_default_guest(machine)) {
 849					/*
 850					 * We assume all symbols of a module are
 851					 * continuous in * kallsyms, so curr_map
 852					 * points to a module and all its
 853					 * symbols are in its kmap. Mark it as
 854					 * loaded.
 855					 */
 856					dso__set_loaded(curr_map->dso);
 857				}
 858
 
 859				curr_map = maps__find_by_name(kmaps, module);
 860				if (curr_map == NULL) {
 861					pr_debug("%s/proc/{kallsyms,modules} "
 862					         "inconsistency while looking "
 863						 "for \"%s\" module!\n",
 864						 machine->root_dir, module);
 865					curr_map = initial_map;
 866					goto discard_symbol;
 867				}
 868
 869				if (curr_map->dso->loaded &&
 870				    !machine__is_default_guest(machine))
 871					goto discard_symbol;
 872			}
 873			/*
 874			 * So that we look just like we get from .ko files,
 875			 * i.e. not prelinked, relative to initial_map->start.
 876			 */
 877			pos->start = curr_map->map_ip(curr_map, pos->start);
 878			pos->end   = curr_map->map_ip(curr_map, pos->end);
 879		} else if (x86_64 && is_entry_trampoline(pos->name)) {
 880			/*
 881			 * These symbols are not needed anymore since the
 882			 * trampoline maps refer to the text section and it's
 883			 * symbols instead. Avoid having to deal with
 884			 * relocations, and the assumption that the first symbol
 885			 * is the start of kernel text, by simply removing the
 886			 * symbols at this point.
 887			 */
 888			goto discard_symbol;
 889		} else if (curr_map != initial_map) {
 890			char dso_name[PATH_MAX];
 891			struct dso *ndso;
 892
 893			if (delta) {
 894				/* Kernel was relocated at boot time */
 895				pos->start -= delta;
 896				pos->end -= delta;
 897			}
 898
 899			if (count == 0) {
 900				curr_map = initial_map;
 
 901				goto add_symbol;
 902			}
 903
 904			if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
 905				snprintf(dso_name, sizeof(dso_name),
 906					"[guest.kernel].%d",
 907					kernel_range++);
 908			else
 909				snprintf(dso_name, sizeof(dso_name),
 910					"[kernel].%d",
 911					kernel_range++);
 912
 913			ndso = dso__new(dso_name);
 
 914			if (ndso == NULL)
 915				return -1;
 916
 917			ndso->kernel = dso->kernel;
 918
 919			curr_map = map__new2(pos->start, ndso);
 920			if (curr_map == NULL) {
 921				dso__put(ndso);
 922				return -1;
 923			}
 924
 925			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 926			maps__insert(kmaps, curr_map);
 
 
 
 
 927			++kernel_range;
 928		} else if (delta) {
 929			/* Kernel was relocated at boot time */
 930			pos->start -= delta;
 931			pos->end -= delta;
 932		}
 933add_symbol:
 934		if (curr_map != initial_map) {
 
 
 935			rb_erase_cached(&pos->rb_node, root);
 936			symbols__insert(&curr_map->dso->symbols, pos);
 937			++moved;
 938		} else
 939			++count;
 940
 941		continue;
 942discard_symbol:
 943		rb_erase_cached(&pos->rb_node, root);
 944		symbol__delete(pos);
 945	}
 946
 947	if (curr_map != initial_map &&
 948	    dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 949	    machine__is_default_guest(kmaps->machine)) {
 950		dso__set_loaded(curr_map->dso);
 951	}
 952
 953	return count + moved;
 954}
 955
 956bool symbol__restricted_filename(const char *filename,
 957				 const char *restricted_filename)
 958{
 959	bool restricted = false;
 960
 961	if (symbol_conf.kptr_restrict) {
 962		char *r = realpath(filename, NULL);
 963
 964		if (r != NULL) {
 965			restricted = strcmp(r, restricted_filename) == 0;
 966			free(r);
 967			return restricted;
 968		}
 969	}
 970
 971	return restricted;
 972}
 973
 974struct module_info {
 975	struct rb_node rb_node;
 976	char *name;
 977	u64 start;
 978};
 979
 980static void add_module(struct module_info *mi, struct rb_root *modules)
 981{
 982	struct rb_node **p = &modules->rb_node;
 983	struct rb_node *parent = NULL;
 984	struct module_info *m;
 985
 986	while (*p != NULL) {
 987		parent = *p;
 988		m = rb_entry(parent, struct module_info, rb_node);
 989		if (strcmp(mi->name, m->name) < 0)
 990			p = &(*p)->rb_left;
 991		else
 992			p = &(*p)->rb_right;
 993	}
 994	rb_link_node(&mi->rb_node, parent, p);
 995	rb_insert_color(&mi->rb_node, modules);
 996}
 997
 998static void delete_modules(struct rb_root *modules)
 999{
1000	struct module_info *mi;
1001	struct rb_node *next = rb_first(modules);
1002
1003	while (next) {
1004		mi = rb_entry(next, struct module_info, rb_node);
1005		next = rb_next(&mi->rb_node);
1006		rb_erase(&mi->rb_node, modules);
1007		zfree(&mi->name);
1008		free(mi);
1009	}
1010}
1011
1012static struct module_info *find_module(const char *name,
1013				       struct rb_root *modules)
1014{
1015	struct rb_node *n = modules->rb_node;
1016
1017	while (n) {
1018		struct module_info *m;
1019		int cmp;
1020
1021		m = rb_entry(n, struct module_info, rb_node);
1022		cmp = strcmp(name, m->name);
1023		if (cmp < 0)
1024			n = n->rb_left;
1025		else if (cmp > 0)
1026			n = n->rb_right;
1027		else
1028			return m;
1029	}
1030
1031	return NULL;
1032}
1033
1034static int __read_proc_modules(void *arg, const char *name, u64 start,
1035			       u64 size __maybe_unused)
1036{
1037	struct rb_root *modules = arg;
1038	struct module_info *mi;
1039
1040	mi = zalloc(sizeof(struct module_info));
1041	if (!mi)
1042		return -ENOMEM;
1043
1044	mi->name = strdup(name);
1045	mi->start = start;
1046
1047	if (!mi->name) {
1048		free(mi);
1049		return -ENOMEM;
1050	}
1051
1052	add_module(mi, modules);
1053
1054	return 0;
1055}
1056
1057static int read_proc_modules(const char *filename, struct rb_root *modules)
1058{
1059	if (symbol__restricted_filename(filename, "/proc/modules"))
1060		return -1;
1061
1062	if (modules__parse(filename, modules, __read_proc_modules)) {
1063		delete_modules(modules);
1064		return -1;
1065	}
1066
1067	return 0;
1068}
1069
1070int compare_proc_modules(const char *from, const char *to)
1071{
1072	struct rb_root from_modules = RB_ROOT;
1073	struct rb_root to_modules = RB_ROOT;
1074	struct rb_node *from_node, *to_node;
1075	struct module_info *from_m, *to_m;
1076	int ret = -1;
1077
1078	if (read_proc_modules(from, &from_modules))
1079		return -1;
1080
1081	if (read_proc_modules(to, &to_modules))
1082		goto out_delete_from;
1083
1084	from_node = rb_first(&from_modules);
1085	to_node = rb_first(&to_modules);
1086	while (from_node) {
1087		if (!to_node)
1088			break;
1089
1090		from_m = rb_entry(from_node, struct module_info, rb_node);
1091		to_m = rb_entry(to_node, struct module_info, rb_node);
1092
1093		if (from_m->start != to_m->start ||
1094		    strcmp(from_m->name, to_m->name))
1095			break;
1096
1097		from_node = rb_next(from_node);
1098		to_node = rb_next(to_node);
1099	}
1100
1101	if (!from_node && !to_node)
1102		ret = 0;
1103
1104	delete_modules(&to_modules);
1105out_delete_from:
1106	delete_modules(&from_modules);
1107
1108	return ret;
1109}
1110
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1111static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1112{
1113	struct rb_root modules = RB_ROOT;
1114	struct map *old_map;
1115	int err;
1116
1117	err = read_proc_modules(filename, &modules);
1118	if (err)
1119		return err;
1120
1121	maps__for_each_entry(kmaps, old_map) {
1122		struct module_info *mi;
1123
1124		if (!__map__is_kmodule(old_map)) {
1125			continue;
1126		}
1127
1128		/* Module must be in memory at the same address */
1129		mi = find_module(old_map->dso->short_name, &modules);
1130		if (!mi || mi->start != old_map->start) {
1131			err = -EINVAL;
1132			goto out;
1133		}
1134	}
1135out:
1136	delete_modules(&modules);
1137	return err;
1138}
1139
1140/*
1141 * If kallsyms is referenced by name then we look for filename in the same
1142 * directory.
1143 */
1144static bool filename_from_kallsyms_filename(char *filename,
1145					    const char *base_name,
1146					    const char *kallsyms_filename)
1147{
1148	char *name;
1149
1150	strcpy(filename, kallsyms_filename);
1151	name = strrchr(filename, '/');
1152	if (!name)
1153		return false;
1154
1155	name += 1;
1156
1157	if (!strcmp(name, "kallsyms")) {
1158		strcpy(name, base_name);
1159		return true;
1160	}
1161
1162	return false;
1163}
1164
1165static int validate_kcore_modules(const char *kallsyms_filename,
1166				  struct map *map)
1167{
1168	struct maps *kmaps = map__kmaps(map);
1169	char modules_filename[PATH_MAX];
1170
1171	if (!kmaps)
1172		return -EINVAL;
1173
1174	if (!filename_from_kallsyms_filename(modules_filename, "modules",
1175					     kallsyms_filename))
1176		return -EINVAL;
1177
1178	if (do_validate_kcore_modules(modules_filename, kmaps))
1179		return -EINVAL;
1180
1181	return 0;
1182}
1183
1184static int validate_kcore_addresses(const char *kallsyms_filename,
1185				    struct map *map)
1186{
1187	struct kmap *kmap = map__kmap(map);
1188
1189	if (!kmap)
1190		return -EINVAL;
1191
1192	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1193		u64 start;
1194
1195		if (kallsyms__get_function_start(kallsyms_filename,
1196						 kmap->ref_reloc_sym->name, &start))
1197			return -ENOENT;
1198		if (start != kmap->ref_reloc_sym->addr)
1199			return -EINVAL;
1200	}
1201
1202	return validate_kcore_modules(kallsyms_filename, map);
1203}
1204
1205struct kcore_mapfn_data {
1206	struct dso *dso;
1207	struct list_head maps;
1208};
1209
1210static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1211{
1212	struct kcore_mapfn_data *md = data;
1213	struct map *map;
1214
1215	map = map__new2(start, md->dso);
1216	if (map == NULL)
1217		return -ENOMEM;
1218
1219	map->end = map->start + len;
1220	map->pgoff = pgoff;
 
 
 
1221
1222	list_add(&map->node, &md->maps);
 
 
 
1223
1224	return 0;
1225}
1226
1227/*
1228 * Merges map into maps by splitting the new map within the existing map
1229 * regions.
1230 */
1231int maps__merge_in(struct maps *kmaps, struct map *new_map)
1232{
1233	struct map *old_map;
1234	LIST_HEAD(merged);
1235
1236	maps__for_each_entry(kmaps, old_map) {
1237		/* no overload with this one */
1238		if (new_map->end < old_map->start ||
1239		    new_map->start >= old_map->end)
1240			continue;
1241
1242		if (new_map->start < old_map->start) {
1243			/*
1244			 * |new......
1245			 *       |old....
1246			 */
1247			if (new_map->end < old_map->end) {
1248				/*
1249				 * |new......|     -> |new..|
1250				 *       |old....| ->       |old....|
1251				 */
1252				new_map->end = old_map->start;
1253			} else {
1254				/*
1255				 * |new.............| -> |new..|       |new..|
1256				 *       |old....|    ->       |old....|
1257				 */
1258				struct map *m = map__clone(new_map);
1259
1260				if (!m)
1261					return -ENOMEM;
1262
1263				m->end = old_map->start;
1264				list_add_tail(&m->node, &merged);
1265				new_map->pgoff += old_map->end - new_map->start;
1266				new_map->start = old_map->end;
1267			}
1268		} else {
1269			/*
1270			 *      |new......
1271			 * |old....
1272			 */
1273			if (new_map->end < old_map->end) {
1274				/*
1275				 *      |new..|   -> x
1276				 * |old.........| -> |old.........|
1277				 */
1278				map__put(new_map);
1279				new_map = NULL;
1280				break;
1281			} else {
1282				/*
1283				 *      |new......| ->         |new...|
1284				 * |old....|        -> |old....|
1285				 */
1286				new_map->pgoff += old_map->end - new_map->start;
1287				new_map->start = old_map->end;
1288			}
1289		}
1290	}
1291
1292	while (!list_empty(&merged)) {
1293		old_map = list_entry(merged.next, struct map, node);
1294		list_del_init(&old_map->node);
1295		maps__insert(kmaps, old_map);
1296		map__put(old_map);
1297	}
1298
1299	if (new_map) {
1300		maps__insert(kmaps, new_map);
1301		map__put(new_map);
1302	}
1303	return 0;
1304}
1305
1306static int dso__load_kcore(struct dso *dso, struct map *map,
1307			   const char *kallsyms_filename)
1308{
1309	struct maps *kmaps = map__kmaps(map);
1310	struct kcore_mapfn_data md;
1311	struct map *old_map, *new_map, *replacement_map = NULL, *next;
1312	struct machine *machine;
1313	bool is_64_bit;
1314	int err, fd;
1315	char kcore_filename[PATH_MAX];
1316	u64 stext;
1317
1318	if (!kmaps)
1319		return -EINVAL;
1320
1321	machine = kmaps->machine;
1322
1323	/* This function requires that the map is the kernel map */
1324	if (!__map__is_kernel(map))
1325		return -EINVAL;
1326
1327	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1328					     kallsyms_filename))
1329		return -EINVAL;
1330
1331	/* Modules and kernel must be present at their original addresses */
1332	if (validate_kcore_addresses(kallsyms_filename, map))
1333		return -EINVAL;
1334
1335	md.dso = dso;
1336	INIT_LIST_HEAD(&md.maps);
1337
1338	fd = open(kcore_filename, O_RDONLY);
1339	if (fd < 0) {
1340		pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1341			 kcore_filename);
1342		return -EINVAL;
1343	}
1344
1345	/* Read new maps into temporary lists */
1346	err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md,
1347			      &is_64_bit);
1348	if (err)
1349		goto out_err;
1350	dso->is_64_bit = is_64_bit;
1351
1352	if (list_empty(&md.maps)) {
1353		err = -EINVAL;
1354		goto out_err;
1355	}
1356
1357	/* Remove old maps */
1358	maps__for_each_entry_safe(kmaps, old_map, next) {
1359		/*
1360		 * We need to preserve eBPF maps even if they are
1361		 * covered by kcore, because we need to access
1362		 * eBPF dso for source data.
1363		 */
1364		if (old_map != map && !__map__is_bpf_prog(old_map))
1365			maps__remove(kmaps, old_map);
1366	}
1367	machine->trampolines_mapped = false;
1368
1369	/* Find the kernel map using the '_stext' symbol */
1370	if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1371		list_for_each_entry(new_map, &md.maps, node) {
1372			if (stext >= new_map->start && stext < new_map->end) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1373				replacement_map = new_map;
1374				break;
1375			}
1376		}
1377	}
1378
1379	if (!replacement_map)
1380		replacement_map = list_entry(md.maps.next, struct map, node);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1381
1382	/* Add new maps */
1383	while (!list_empty(&md.maps)) {
1384		new_map = list_entry(md.maps.next, struct map, node);
1385		list_del_init(&new_map->node);
1386		if (new_map == replacement_map) {
1387			map->start	= new_map->start;
1388			map->end	= new_map->end;
1389			map->pgoff	= new_map->pgoff;
1390			map->map_ip	= new_map->map_ip;
1391			map->unmap_ip	= new_map->unmap_ip;
1392			/* Ensure maps are correctly ordered */
1393			map__get(map);
1394			maps__remove(kmaps, map);
1395			maps__insert(kmaps, map);
1396			map__put(map);
1397			map__put(new_map);
1398		} else {
1399			/*
1400			 * Merge kcore map into existing maps,
1401			 * and ensure that current maps (eBPF)
1402			 * stay intact.
1403			 */
1404			if (maps__merge_in(kmaps, new_map))
 
1405				goto out_err;
 
1406		}
 
1407	}
1408
1409	if (machine__is(machine, "x86_64")) {
1410		u64 addr;
1411
1412		/*
1413		 * If one of the corresponding symbols is there, assume the
1414		 * entry trampoline maps are too.
1415		 */
1416		if (!kallsyms__get_function_start(kallsyms_filename,
1417						  ENTRY_TRAMPOLINE_NAME,
1418						  &addr))
1419			machine->trampolines_mapped = true;
1420	}
1421
1422	/*
1423	 * Set the data type and long name so that kcore can be read via
1424	 * dso__data_read_addr().
1425	 */
1426	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1427		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1428	else
1429		dso->binary_type = DSO_BINARY_TYPE__KCORE;
1430	dso__set_long_name(dso, strdup(kcore_filename), true);
1431
1432	close(fd);
1433
1434	if (map->prot & PROT_EXEC)
1435		pr_debug("Using %s for kernel object code\n", kcore_filename);
1436	else
1437		pr_debug("Using %s for kernel data\n", kcore_filename);
1438
1439	return 0;
1440
1441out_err:
1442	while (!list_empty(&md.maps)) {
1443		map = list_entry(md.maps.next, struct map, node);
1444		list_del_init(&map->node);
1445		map__put(map);
 
 
 
1446	}
1447	close(fd);
1448	return -EINVAL;
1449}
1450
1451/*
1452 * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1453 * delta based on the relocation reference symbol.
1454 */
1455static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1456{
1457	u64 addr;
1458
1459	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1460		return 0;
1461
1462	if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1463		return -1;
1464
1465	*delta = addr - kmap->ref_reloc_sym->addr;
1466	return 0;
1467}
1468
1469int __dso__load_kallsyms(struct dso *dso, const char *filename,
1470			 struct map *map, bool no_kcore)
1471{
1472	struct kmap *kmap = map__kmap(map);
1473	u64 delta = 0;
1474
1475	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1476		return -1;
1477
1478	if (!kmap || !kmap->kmaps)
1479		return -1;
1480
1481	if (dso__load_all_kallsyms(dso, filename) < 0)
1482		return -1;
1483
1484	if (kallsyms__delta(kmap, filename, &delta))
1485		return -1;
1486
1487	symbols__fixup_end(&dso->symbols, true);
1488	symbols__fixup_duplicate(&dso->symbols);
1489
1490	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1491		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1492	else
1493		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1494
1495	if (!no_kcore && !dso__load_kcore(dso, map, filename))
1496		return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1497	else
1498		return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1499}
1500
1501int dso__load_kallsyms(struct dso *dso, const char *filename,
1502		       struct map *map)
1503{
1504	return __dso__load_kallsyms(dso, filename, map, false);
1505}
1506
1507static int dso__load_perf_map(const char *map_path, struct dso *dso)
1508{
1509	char *line = NULL;
1510	size_t n;
1511	FILE *file;
1512	int nr_syms = 0;
1513
1514	file = fopen(map_path, "r");
1515	if (file == NULL)
1516		goto out_failure;
1517
1518	while (!feof(file)) {
1519		u64 start, size;
1520		struct symbol *sym;
1521		int line_len, len;
1522
1523		line_len = getline(&line, &n, file);
1524		if (line_len < 0)
1525			break;
1526
1527		if (!line)
1528			goto out_failure;
1529
1530		line[--line_len] = '\0'; /* \n */
1531
1532		len = hex2u64(line, &start);
1533
1534		len++;
1535		if (len + 2 >= line_len)
1536			continue;
1537
1538		len += hex2u64(line + len, &size);
1539
1540		len++;
1541		if (len + 2 >= line_len)
1542			continue;
1543
1544		sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1545
1546		if (sym == NULL)
1547			goto out_delete_line;
1548
1549		symbols__insert(&dso->symbols, sym);
1550		nr_syms++;
1551	}
1552
1553	free(line);
1554	fclose(file);
1555
1556	return nr_syms;
1557
1558out_delete_line:
1559	free(line);
1560out_failure:
1561	return -1;
1562}
1563
1564#ifdef HAVE_LIBBFD_SUPPORT
1565#define PACKAGE 'perf'
1566#include <bfd.h>
1567
1568static int bfd_symbols__cmpvalue(const void *a, const void *b)
1569{
1570	const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1571
1572	if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1573		return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1574
1575	return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1576}
1577
1578static int bfd2elf_binding(asymbol *symbol)
1579{
1580	if (symbol->flags & BSF_WEAK)
1581		return STB_WEAK;
1582	if (symbol->flags & BSF_GLOBAL)
1583		return STB_GLOBAL;
1584	if (symbol->flags & BSF_LOCAL)
1585		return STB_LOCAL;
1586	return -1;
1587}
1588
1589int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1590{
1591	int err = -1;
1592	long symbols_size, symbols_count, i;
1593	asection *section;
1594	asymbol **symbols, *sym;
1595	struct symbol *symbol;
1596	bfd *abfd;
1597	u64 start, len;
1598
1599	abfd = bfd_openr(debugfile, NULL);
1600	if (!abfd)
1601		return -1;
1602
1603	if (!bfd_check_format(abfd, bfd_object)) {
1604		pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1605			  dso->long_name);
1606		goto out_close;
1607	}
1608
1609	if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1610		goto out_close;
1611
1612	symbols_size = bfd_get_symtab_upper_bound(abfd);
1613	if (symbols_size == 0) {
1614		bfd_close(abfd);
1615		return 0;
1616	}
1617
1618	if (symbols_size < 0)
1619		goto out_close;
1620
1621	symbols = malloc(symbols_size);
1622	if (!symbols)
1623		goto out_close;
1624
1625	symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1626	if (symbols_count < 0)
1627		goto out_free;
1628
1629	section = bfd_get_section_by_name(abfd, ".text");
1630	if (section) {
1631		for (i = 0; i < symbols_count; ++i) {
1632			if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
1633			    !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
1634				break;
1635		}
1636		if (i < symbols_count) {
1637			/* PE symbols can only have 4 bytes, so use .text high bits */
1638			dso->text_offset = section->vma - (u32)section->vma;
1639			dso->text_offset += (u32)bfd_asymbol_value(symbols[i]);
 
 
1640		} else {
1641			dso->text_offset = section->vma - section->filepos;
 
1642		}
1643	}
1644
1645	qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1646
1647#ifdef bfd_get_section
1648#define bfd_asymbol_section bfd_get_section
1649#endif
1650	for (i = 0; i < symbols_count; ++i) {
1651		sym = symbols[i];
1652		section = bfd_asymbol_section(sym);
1653		if (bfd2elf_binding(sym) < 0)
1654			continue;
1655
1656		while (i + 1 < symbols_count &&
1657		       bfd_asymbol_section(symbols[i + 1]) == section &&
1658		       bfd2elf_binding(symbols[i + 1]) < 0)
1659			i++;
1660
1661		if (i + 1 < symbols_count &&
1662		    bfd_asymbol_section(symbols[i + 1]) == section)
1663			len = symbols[i + 1]->value - sym->value;
1664		else
1665			len = section->size - sym->value;
1666
1667		start = bfd_asymbol_value(sym) - dso->text_offset;
1668		symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1669				     bfd_asymbol_name(sym));
1670		if (!symbol)
1671			goto out_free;
1672
1673		symbols__insert(&dso->symbols, symbol);
1674	}
1675#ifdef bfd_get_section
1676#undef bfd_asymbol_section
1677#endif
1678
1679	symbols__fixup_end(&dso->symbols, false);
1680	symbols__fixup_duplicate(&dso->symbols);
1681	dso->adjust_symbols = 1;
1682
1683	err = 0;
1684out_free:
1685	free(symbols);
1686out_close:
1687	bfd_close(abfd);
1688	return err;
1689}
1690#endif
1691
1692static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1693					   enum dso_binary_type type)
1694{
1695	switch (type) {
1696	case DSO_BINARY_TYPE__JAVA_JIT:
1697	case DSO_BINARY_TYPE__DEBUGLINK:
1698	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1699	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1700	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1701	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1702	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1703	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1704		return !kmod && dso->kernel == DSO_SPACE__USER;
1705
1706	case DSO_BINARY_TYPE__KALLSYMS:
1707	case DSO_BINARY_TYPE__VMLINUX:
1708	case DSO_BINARY_TYPE__KCORE:
1709		return dso->kernel == DSO_SPACE__KERNEL;
1710
1711	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1712	case DSO_BINARY_TYPE__GUEST_VMLINUX:
1713	case DSO_BINARY_TYPE__GUEST_KCORE:
1714		return dso->kernel == DSO_SPACE__KERNEL_GUEST;
1715
1716	case DSO_BINARY_TYPE__GUEST_KMODULE:
1717	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1718	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1719	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1720		/*
1721		 * kernel modules know their symtab type - it's set when
1722		 * creating a module dso in machine__addnew_module_map().
1723		 */
1724		return kmod && dso->symtab_type == type;
1725
1726	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1727	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1728		return true;
1729
1730	case DSO_BINARY_TYPE__BPF_PROG_INFO:
1731	case DSO_BINARY_TYPE__BPF_IMAGE:
1732	case DSO_BINARY_TYPE__OOL:
1733	case DSO_BINARY_TYPE__NOT_FOUND:
1734	default:
1735		return false;
1736	}
1737}
1738
1739/* Checks for the existence of the perf-<pid>.map file in two different
1740 * locations.  First, if the process is a separate mount namespace, check in
1741 * that namespace using the pid of the innermost pid namespace.  If's not in a
1742 * namespace, or the file can't be found there, try in the mount namespace of
1743 * the tracing process using our view of its pid.
1744 */
1745static int dso__find_perf_map(char *filebuf, size_t bufsz,
1746			      struct nsinfo **nsip)
1747{
1748	struct nscookie nsc;
1749	struct nsinfo *nsi;
1750	struct nsinfo *nnsi;
1751	int rc = -1;
1752
1753	nsi = *nsip;
1754
1755	if (nsinfo__need_setns(nsi)) {
1756		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
1757		nsinfo__mountns_enter(nsi, &nsc);
1758		rc = access(filebuf, R_OK);
1759		nsinfo__mountns_exit(&nsc);
1760		if (rc == 0)
1761			return rc;
1762	}
1763
1764	nnsi = nsinfo__copy(nsi);
1765	if (nnsi) {
1766		nsinfo__put(nsi);
1767
1768		nsinfo__clear_need_setns(nnsi);
1769		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
1770		*nsip = nnsi;
1771		rc = 0;
1772	}
1773
1774	return rc;
1775}
1776
1777int dso__load(struct dso *dso, struct map *map)
1778{
1779	char *name;
1780	int ret = -1;
1781	u_int i;
1782	struct machine *machine = NULL;
1783	char *root_dir = (char *) "";
1784	int ss_pos = 0;
1785	struct symsrc ss_[2];
1786	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1787	bool kmod;
1788	bool perfmap;
1789	struct build_id bid;
1790	struct nscookie nsc;
1791	char newmapname[PATH_MAX];
1792	const char *map_path = dso->long_name;
 
 
 
1793
1794	mutex_lock(&dso->lock);
1795	perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
1796	if (perfmap) {
1797		if (dso->nsinfo && (dso__find_perf_map(newmapname,
1798		    sizeof(newmapname), &dso->nsinfo) == 0)) {
 
1799			map_path = newmapname;
1800		}
1801	}
1802
1803	nsinfo__mountns_enter(dso->nsinfo, &nsc);
1804
1805	/* check again under the dso->lock */
1806	if (dso__loaded(dso)) {
1807		ret = 1;
1808		goto out;
1809	}
1810
1811	kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1812		dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1813		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1814		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1815
1816	if (dso->kernel && !kmod) {
1817		if (dso->kernel == DSO_SPACE__KERNEL)
1818			ret = dso__load_kernel_sym(dso, map);
1819		else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1820			ret = dso__load_guest_kernel_sym(dso, map);
1821
1822		machine = map__kmaps(map)->machine;
1823		if (machine__is(machine, "x86_64"))
1824			machine__map_x86_64_entry_trampolines(machine, dso);
1825		goto out;
1826	}
1827
1828	dso->adjust_symbols = 0;
1829
1830	if (perfmap) {
1831		ret = dso__load_perf_map(map_path, dso);
1832		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1833					     DSO_BINARY_TYPE__NOT_FOUND;
 
1834		goto out;
1835	}
1836
1837	if (machine)
1838		root_dir = machine->root_dir;
1839
1840	name = malloc(PATH_MAX);
1841	if (!name)
1842		goto out;
1843
1844	/*
1845	 * Read the build id if possible. This is required for
1846	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1847	 */
1848	if (!dso->has_build_id &&
1849	    is_regular_file(dso->long_name)) {
1850	    __symbol__join_symfs(name, PATH_MAX, dso->long_name);
1851		if (filename__read_build_id(name, &bid) > 0)
1852			dso__set_build_id(dso, &bid);
1853	}
1854
1855	/*
1856	 * Iterate over candidate debug images.
1857	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1858	 * and/or opd section) for processing.
1859	 */
1860	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1861		struct symsrc *ss = &ss_[ss_pos];
1862		bool next_slot = false;
1863		bool is_reg;
1864		bool nsexit;
1865		int bfdrc = -1;
1866		int sirc = -1;
1867
1868		enum dso_binary_type symtab_type = binary_type_symtab[i];
1869
1870		nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1871		    symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1872
1873		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1874			continue;
1875
1876		if (dso__read_binary_type_filename(dso, symtab_type,
1877						   root_dir, name, PATH_MAX))
1878			continue;
1879
1880		if (nsexit)
1881			nsinfo__mountns_exit(&nsc);
1882
1883		is_reg = is_regular_file(name);
1884		if (!is_reg && errno == ENOENT && dso->nsinfo) {
1885			char *new_name = filename_with_chroot(dso->nsinfo->pid,
1886							      name);
1887			if (new_name) {
1888				is_reg = is_regular_file(new_name);
1889				strlcpy(name, new_name, PATH_MAX);
1890				free(new_name);
1891			}
1892		}
1893
1894#ifdef HAVE_LIBBFD_SUPPORT
1895		if (is_reg)
1896			bfdrc = dso__load_bfd_symbols(dso, name);
1897#endif
1898		if (is_reg && bfdrc < 0)
1899			sirc = symsrc__init(ss, dso, name, symtab_type);
1900
1901		if (nsexit)
1902			nsinfo__mountns_enter(dso->nsinfo, &nsc);
1903
1904		if (bfdrc == 0) {
1905			ret = 0;
1906			break;
1907		}
1908
1909		if (!is_reg || sirc < 0)
1910			continue;
1911
1912		if (!syms_ss && symsrc__has_symtab(ss)) {
1913			syms_ss = ss;
1914			next_slot = true;
1915			if (!dso->symsrc_filename)
1916				dso->symsrc_filename = strdup(name);
1917		}
1918
1919		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1920			runtime_ss = ss;
1921			next_slot = true;
1922		}
1923
1924		if (next_slot) {
1925			ss_pos++;
1926
 
 
 
1927			if (syms_ss && runtime_ss)
1928				break;
1929		} else {
1930			symsrc__destroy(ss);
1931		}
1932
1933	}
1934
1935	if (!runtime_ss && !syms_ss)
1936		goto out_free;
1937
1938	if (runtime_ss && !syms_ss) {
1939		syms_ss = runtime_ss;
1940	}
1941
1942	/* We'll have to hope for the best */
1943	if (!runtime_ss && syms_ss)
1944		runtime_ss = syms_ss;
1945
1946	if (syms_ss)
1947		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1948	else
1949		ret = -1;
1950
1951	if (ret > 0) {
1952		int nr_plt;
1953
1954		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
1955		if (nr_plt > 0)
1956			ret += nr_plt;
1957	}
1958
1959	for (; ss_pos > 0; ss_pos--)
1960		symsrc__destroy(&ss_[ss_pos - 1]);
1961out_free:
1962	free(name);
1963	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1964		ret = 0;
1965out:
1966	dso__set_loaded(dso);
1967	mutex_unlock(&dso->lock);
1968	nsinfo__mountns_exit(&nsc);
1969
1970	return ret;
1971}
1972
1973static int map__strcmp(const void *a, const void *b)
1974{
1975	const struct map *ma = *(const struct map **)a, *mb = *(const struct map **)b;
1976	return strcmp(ma->dso->short_name, mb->dso->short_name);
1977}
1978
1979static int map__strcmp_name(const void *name, const void *b)
1980{
1981	const struct map *map = *(const struct map **)b;
1982	return strcmp(name, map->dso->short_name);
1983}
1984
1985void __maps__sort_by_name(struct maps *maps)
1986{
1987	qsort(maps->maps_by_name, maps->nr_maps, sizeof(struct map *), map__strcmp);
1988}
1989
1990static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
1991{
1992	struct map *map;
1993	struct map **maps_by_name = realloc(maps->maps_by_name, maps->nr_maps * sizeof(map));
1994	int i = 0;
1995
1996	if (maps_by_name == NULL)
1997		return -1;
1998
1999	maps->maps_by_name = maps_by_name;
2000	maps->nr_maps_allocated = maps->nr_maps;
2001
2002	maps__for_each_entry(maps, map)
2003		maps_by_name[i++] = map;
2004
2005	__maps__sort_by_name(maps);
2006	return 0;
2007}
2008
2009static struct map *__maps__find_by_name(struct maps *maps, const char *name)
2010{
2011	struct map **mapp;
2012
2013	if (maps->maps_by_name == NULL &&
2014	    map__groups__sort_by_name_from_rbtree(maps))
2015		return NULL;
2016
2017	mapp = bsearch(name, maps->maps_by_name, maps->nr_maps, sizeof(*mapp), map__strcmp_name);
2018	if (mapp)
2019		return *mapp;
2020	return NULL;
2021}
2022
2023struct map *maps__find_by_name(struct maps *maps, const char *name)
2024{
2025	struct map *map;
2026
2027	down_read(&maps->lock);
2028
2029	if (maps->last_search_by_name && strcmp(maps->last_search_by_name->dso->short_name, name) == 0) {
2030		map = maps->last_search_by_name;
2031		goto out_unlock;
2032	}
2033	/*
2034	 * If we have maps->maps_by_name, then the name isn't in the rbtree,
2035	 * as maps->maps_by_name mirrors the rbtree when lookups by name are
2036	 * made.
2037	 */
2038	map = __maps__find_by_name(maps, name);
2039	if (map || maps->maps_by_name != NULL)
2040		goto out_unlock;
2041
2042	/* Fallback to traversing the rbtree... */
2043	maps__for_each_entry(maps, map)
2044		if (strcmp(map->dso->short_name, name) == 0) {
2045			maps->last_search_by_name = map;
2046			goto out_unlock;
2047		}
2048
2049	map = NULL;
2050
2051out_unlock:
2052	up_read(&maps->lock);
2053	return map;
2054}
2055
2056int dso__load_vmlinux(struct dso *dso, struct map *map,
2057		      const char *vmlinux, bool vmlinux_allocated)
2058{
2059	int err = -1;
2060	struct symsrc ss;
2061	char symfs_vmlinux[PATH_MAX];
2062	enum dso_binary_type symtab_type;
2063
2064	if (vmlinux[0] == '/')
2065		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
2066	else
2067		symbol__join_symfs(symfs_vmlinux, vmlinux);
2068
2069	if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2070		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2071	else
2072		symtab_type = DSO_BINARY_TYPE__VMLINUX;
2073
2074	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
 
 
2075		return -1;
 
 
 
 
 
 
 
 
 
 
 
2076
2077	err = dso__load_sym(dso, map, &ss, &ss, 0);
2078	symsrc__destroy(&ss);
2079
2080	if (err > 0) {
2081		if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2082			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2083		else
2084			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
2085		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
2086		dso__set_loaded(dso);
2087		pr_debug("Using %s for symbols\n", symfs_vmlinux);
2088	}
2089
2090	return err;
2091}
2092
2093int dso__load_vmlinux_path(struct dso *dso, struct map *map)
2094{
2095	int i, err = 0;
2096	char *filename = NULL;
2097
2098	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
2099		 vmlinux_path__nr_entries + 1);
2100
2101	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
2102		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
2103		if (err > 0)
2104			goto out;
2105	}
2106
2107	if (!symbol_conf.ignore_vmlinux_buildid)
2108		filename = dso__build_id_filename(dso, NULL, 0, false);
2109	if (filename != NULL) {
2110		err = dso__load_vmlinux(dso, map, filename, true);
2111		if (err > 0)
2112			goto out;
2113		free(filename);
2114	}
2115out:
2116	return err;
2117}
2118
2119static bool visible_dir_filter(const char *name, struct dirent *d)
2120{
2121	if (d->d_type != DT_DIR)
2122		return false;
2123	return lsdir_no_dot_filter(name, d);
2124}
2125
2126static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2127{
2128	char kallsyms_filename[PATH_MAX];
2129	int ret = -1;
2130	struct strlist *dirs;
2131	struct str_node *nd;
2132
2133	dirs = lsdir(dir, visible_dir_filter);
2134	if (!dirs)
2135		return -1;
2136
2137	strlist__for_each_entry(nd, dirs) {
2138		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2139			  "%s/%s/kallsyms", dir, nd->s);
2140		if (!validate_kcore_addresses(kallsyms_filename, map)) {
2141			strlcpy(dir, kallsyms_filename, dir_sz);
2142			ret = 0;
2143			break;
2144		}
2145	}
2146
2147	strlist__delete(dirs);
2148
2149	return ret;
2150}
2151
2152/*
2153 * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2154 * since access(R_OK) only checks with real UID/GID but open() use effective
2155 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2156 */
2157static bool filename__readable(const char *file)
2158{
2159	int fd = open(file, O_RDONLY);
2160	if (fd < 0)
2161		return false;
2162	close(fd);
2163	return true;
2164}
2165
2166static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2167{
2168	struct build_id bid;
2169	char sbuild_id[SBUILD_ID_SIZE];
2170	bool is_host = false;
2171	char path[PATH_MAX];
2172
2173	if (!dso->has_build_id) {
2174		/*
2175		 * Last resort, if we don't have a build-id and couldn't find
2176		 * any vmlinux file, try the running kernel kallsyms table.
2177		 */
2178		goto proc_kallsyms;
2179	}
2180
2181	if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2182		is_host = dso__build_id_equal(dso, &bid);
2183
2184	/* Try a fast path for /proc/kallsyms if possible */
2185	if (is_host) {
2186		/*
2187		 * Do not check the build-id cache, unless we know we cannot use
2188		 * /proc/kcore or module maps don't match to /proc/kallsyms.
2189		 * To check readability of /proc/kcore, do not use access(R_OK)
2190		 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2191		 * can't check it.
2192		 */
2193		if (filename__readable("/proc/kcore") &&
2194		    !validate_kcore_addresses("/proc/kallsyms", map))
2195			goto proc_kallsyms;
2196	}
2197
2198	build_id__sprintf(&dso->bid, sbuild_id);
2199
2200	/* Find kallsyms in build-id cache with kcore */
2201	scnprintf(path, sizeof(path), "%s/%s/%s",
2202		  buildid_dir, DSO__NAME_KCORE, sbuild_id);
2203
2204	if (!find_matching_kcore(map, path, sizeof(path)))
2205		return strdup(path);
2206
2207	/* Use current /proc/kallsyms if possible */
2208	if (is_host) {
2209proc_kallsyms:
2210		return strdup("/proc/kallsyms");
2211	}
2212
2213	/* Finally, find a cache of kallsyms */
2214	if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2215		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2216		       sbuild_id);
2217		return NULL;
2218	}
2219
2220	return strdup(path);
2221}
2222
2223static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2224{
2225	int err;
2226	const char *kallsyms_filename = NULL;
2227	char *kallsyms_allocated_filename = NULL;
2228	char *filename = NULL;
2229
2230	/*
2231	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
2232	 * it and only it, reporting errors to the user if it cannot be used.
2233	 *
2234	 * For instance, try to analyse an ARM perf.data file _without_ a
2235	 * build-id, or if the user specifies the wrong path to the right
2236	 * vmlinux file, obviously we can't fallback to another vmlinux (a
2237	 * x86_86 one, on the machine where analysis is being performed, say),
2238	 * or worse, /proc/kallsyms.
2239	 *
2240	 * If the specified file _has_ a build-id and there is a build-id
2241	 * section in the perf.data file, we will still do the expected
2242	 * validation in dso__load_vmlinux and will bail out if they don't
2243	 * match.
2244	 */
2245	if (symbol_conf.kallsyms_name != NULL) {
2246		kallsyms_filename = symbol_conf.kallsyms_name;
2247		goto do_kallsyms;
2248	}
2249
2250	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2251		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2252	}
2253
2254	/*
2255	 * Before checking on common vmlinux locations, check if it's
2256	 * stored as standard build id binary (not kallsyms) under
2257	 * .debug cache.
2258	 */
2259	if (!symbol_conf.ignore_vmlinux_buildid)
2260		filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2261	if (filename != NULL) {
2262		err = dso__load_vmlinux(dso, map, filename, true);
2263		if (err > 0)
2264			return err;
2265		free(filename);
2266	}
2267
2268	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2269		err = dso__load_vmlinux_path(dso, map);
2270		if (err > 0)
2271			return err;
2272	}
2273
2274	/* do not try local files if a symfs was given */
2275	if (symbol_conf.symfs[0] != 0)
2276		return -1;
2277
2278	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2279	if (!kallsyms_allocated_filename)
2280		return -1;
2281
2282	kallsyms_filename = kallsyms_allocated_filename;
2283
2284do_kallsyms:
2285	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2286	if (err > 0)
2287		pr_debug("Using %s for symbols\n", kallsyms_filename);
2288	free(kallsyms_allocated_filename);
2289
2290	if (err > 0 && !dso__is_kcore(dso)) {
2291		dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
2292		dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2293		map__fixup_start(map);
2294		map__fixup_end(map);
2295	}
2296
2297	return err;
2298}
2299
2300static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2301{
2302	int err;
2303	const char *kallsyms_filename;
2304	struct machine *machine = map__kmaps(map)->machine;
2305	char path[PATH_MAX];
2306
2307	if (machine->kallsyms_filename) {
2308		kallsyms_filename = machine->kallsyms_filename;
2309	} else if (machine__is_default_guest(machine)) {
2310		/*
2311		 * if the user specified a vmlinux filename, use it and only
2312		 * it, reporting errors to the user if it cannot be used.
2313		 * Or use file guest_kallsyms inputted by user on commandline
2314		 */
2315		if (symbol_conf.default_guest_vmlinux_name != NULL) {
2316			err = dso__load_vmlinux(dso, map,
2317						symbol_conf.default_guest_vmlinux_name,
2318						false);
2319			return err;
2320		}
2321
2322		kallsyms_filename = symbol_conf.default_guest_kallsyms;
2323		if (!kallsyms_filename)
2324			return -1;
2325	} else {
2326		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2327		kallsyms_filename = path;
2328	}
2329
2330	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2331	if (err > 0)
2332		pr_debug("Using %s for symbols\n", kallsyms_filename);
2333	if (err > 0 && !dso__is_kcore(dso)) {
2334		dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
2335		dso__set_long_name(dso, machine->mmap_name, false);
2336		map__fixup_start(map);
2337		map__fixup_end(map);
2338	}
2339
2340	return err;
2341}
2342
2343static void vmlinux_path__exit(void)
2344{
2345	while (--vmlinux_path__nr_entries >= 0)
2346		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2347	vmlinux_path__nr_entries = 0;
2348
2349	zfree(&vmlinux_path);
2350}
2351
2352static const char * const vmlinux_paths[] = {
2353	"vmlinux",
2354	"/boot/vmlinux"
2355};
2356
2357static const char * const vmlinux_paths_upd[] = {
2358	"/boot/vmlinux-%s",
2359	"/usr/lib/debug/boot/vmlinux-%s",
2360	"/lib/modules/%s/build/vmlinux",
2361	"/usr/lib/debug/lib/modules/%s/vmlinux",
2362	"/usr/lib/debug/boot/vmlinux-%s.debug"
2363};
2364
2365static int vmlinux_path__add(const char *new_entry)
2366{
2367	vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2368	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2369		return -1;
2370	++vmlinux_path__nr_entries;
2371
2372	return 0;
2373}
2374
2375static int vmlinux_path__init(struct perf_env *env)
2376{
2377	struct utsname uts;
2378	char bf[PATH_MAX];
2379	char *kernel_version;
2380	unsigned int i;
2381
2382	vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2383			      ARRAY_SIZE(vmlinux_paths_upd)));
2384	if (vmlinux_path == NULL)
2385		return -1;
2386
2387	for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2388		if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2389			goto out_fail;
2390
2391	/* only try kernel version if no symfs was given */
2392	if (symbol_conf.symfs[0] != 0)
2393		return 0;
2394
2395	if (env) {
2396		kernel_version = env->os_release;
2397	} else {
2398		if (uname(&uts) < 0)
2399			goto out_fail;
2400
2401		kernel_version = uts.release;
2402	}
2403
2404	for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2405		snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2406		if (vmlinux_path__add(bf) < 0)
2407			goto out_fail;
2408	}
2409
2410	return 0;
2411
2412out_fail:
2413	vmlinux_path__exit();
2414	return -1;
2415}
2416
2417int setup_list(struct strlist **list, const char *list_str,
2418		      const char *list_name)
2419{
2420	if (list_str == NULL)
2421		return 0;
2422
2423	*list = strlist__new(list_str, NULL);
2424	if (!*list) {
2425		pr_err("problems parsing %s list\n", list_name);
2426		return -1;
2427	}
2428
2429	symbol_conf.has_filter = true;
2430	return 0;
2431}
2432
2433int setup_intlist(struct intlist **list, const char *list_str,
2434		  const char *list_name)
2435{
2436	if (list_str == NULL)
2437		return 0;
2438
2439	*list = intlist__new(list_str);
2440	if (!*list) {
2441		pr_err("problems parsing %s list\n", list_name);
2442		return -1;
2443	}
2444	return 0;
2445}
2446
2447static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
2448{
2449	struct str_node *pos, *tmp;
2450	unsigned long val;
2451	char *sep;
2452	const char *end;
2453	int i = 0, err;
2454
2455	*addr_list = intlist__new(NULL);
2456	if (!*addr_list)
2457		return -1;
2458
2459	strlist__for_each_entry_safe(pos, tmp, sym_list) {
2460		errno = 0;
2461		val = strtoul(pos->s, &sep, 16);
2462		if (errno || (sep == pos->s))
2463			continue;
2464
2465		if (*sep != '\0') {
2466			end = pos->s + strlen(pos->s) - 1;
2467			while (end >= sep && isspace(*end))
2468				end--;
2469
2470			if (end >= sep)
2471				continue;
2472		}
2473
2474		err = intlist__add(*addr_list, val);
2475		if (err)
2476			break;
2477
2478		strlist__remove(sym_list, pos);
2479		i++;
2480	}
2481
2482	if (i == 0) {
2483		intlist__delete(*addr_list);
2484		*addr_list = NULL;
2485	}
2486
2487	return 0;
2488}
2489
2490static bool symbol__read_kptr_restrict(void)
2491{
2492	bool value = false;
2493	FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
 
 
2494
2495	if (fp != NULL) {
2496		char line[8];
2497
2498		if (fgets(line, sizeof(line), fp) != NULL)
2499			value = perf_cap__capable(CAP_SYSLOG) ?
2500					(atoi(line) >= 2) :
2501					(atoi(line) != 0);
2502
2503		fclose(fp);
2504	}
2505
2506	/* Per kernel/kallsyms.c:
2507	 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2508	 */
2509	if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
2510		value = true;
2511
2512	return value;
2513}
2514
2515int symbol__annotation_init(void)
2516{
2517	if (symbol_conf.init_annotation)
2518		return 0;
2519
2520	if (symbol_conf.initialized) {
2521		pr_err("Annotation needs to be init before symbol__init()\n");
2522		return -1;
2523	}
2524
2525	symbol_conf.priv_size += sizeof(struct annotation);
2526	symbol_conf.init_annotation = true;
2527	return 0;
2528}
2529
2530int symbol__init(struct perf_env *env)
2531{
2532	const char *symfs;
2533
2534	if (symbol_conf.initialized)
2535		return 0;
2536
2537	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2538
2539	symbol__elf_init();
2540
2541	if (symbol_conf.sort_by_name)
2542		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2543					  sizeof(struct symbol));
2544
2545	if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2546		return -1;
2547
2548	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2549		pr_err("'.' is the only non valid --field-separator argument\n");
2550		return -1;
2551	}
2552
2553	if (setup_list(&symbol_conf.dso_list,
2554		       symbol_conf.dso_list_str, "dso") < 0)
2555		return -1;
2556
2557	if (setup_list(&symbol_conf.comm_list,
2558		       symbol_conf.comm_list_str, "comm") < 0)
2559		goto out_free_dso_list;
2560
2561	if (setup_intlist(&symbol_conf.pid_list,
2562		       symbol_conf.pid_list_str, "pid") < 0)
2563		goto out_free_comm_list;
2564
2565	if (setup_intlist(&symbol_conf.tid_list,
2566		       symbol_conf.tid_list_str, "tid") < 0)
2567		goto out_free_pid_list;
2568
2569	if (setup_list(&symbol_conf.sym_list,
2570		       symbol_conf.sym_list_str, "symbol") < 0)
2571		goto out_free_tid_list;
2572
2573	if (symbol_conf.sym_list &&
2574	    setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
2575		goto out_free_sym_list;
2576
2577	if (setup_list(&symbol_conf.bt_stop_list,
2578		       symbol_conf.bt_stop_list_str, "symbol") < 0)
2579		goto out_free_sym_list;
2580
2581	/*
2582	 * A path to symbols of "/" is identical to ""
2583	 * reset here for simplicity.
2584	 */
2585	symfs = realpath(symbol_conf.symfs, NULL);
2586	if (symfs == NULL)
2587		symfs = symbol_conf.symfs;
2588	if (strcmp(symfs, "/") == 0)
2589		symbol_conf.symfs = "";
2590	if (symfs != symbol_conf.symfs)
2591		free((void *)symfs);
2592
2593	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2594
2595	symbol_conf.initialized = true;
2596	return 0;
2597
2598out_free_sym_list:
2599	strlist__delete(symbol_conf.sym_list);
2600	intlist__delete(symbol_conf.addr_list);
2601out_free_tid_list:
2602	intlist__delete(symbol_conf.tid_list);
2603out_free_pid_list:
2604	intlist__delete(symbol_conf.pid_list);
2605out_free_comm_list:
2606	strlist__delete(symbol_conf.comm_list);
2607out_free_dso_list:
2608	strlist__delete(symbol_conf.dso_list);
2609	return -1;
2610}
2611
2612void symbol__exit(void)
2613{
2614	if (!symbol_conf.initialized)
2615		return;
2616	strlist__delete(symbol_conf.bt_stop_list);
2617	strlist__delete(symbol_conf.sym_list);
2618	strlist__delete(symbol_conf.dso_list);
2619	strlist__delete(symbol_conf.comm_list);
2620	intlist__delete(symbol_conf.tid_list);
2621	intlist__delete(symbol_conf.pid_list);
2622	intlist__delete(symbol_conf.addr_list);
2623	vmlinux_path__exit();
2624	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2625	symbol_conf.bt_stop_list = NULL;
2626	symbol_conf.initialized = false;
2627}
2628
2629int symbol__config_symfs(const struct option *opt __maybe_unused,
2630			 const char *dir, int unset __maybe_unused)
2631{
2632	char *bf = NULL;
2633	int ret;
2634
2635	symbol_conf.symfs = strdup(dir);
2636	if (symbol_conf.symfs == NULL)
2637		return -ENOMEM;
2638
2639	/* skip the locally configured cache if a symfs is given, and
2640	 * config buildid dir to symfs/.debug
2641	 */
2642	ret = asprintf(&bf, "%s/%s", dir, ".debug");
2643	if (ret < 0)
2644		return -ENOMEM;
2645
2646	set_buildid_dir(bf);
2647
2648	free(bf);
2649	return 0;
2650}
2651
2652struct mem_info *mem_info__get(struct mem_info *mi)
2653{
2654	if (mi)
2655		refcount_inc(&mi->refcnt);
2656	return mi;
2657}
2658
2659void mem_info__put(struct mem_info *mi)
2660{
2661	if (mi && refcount_dec_and_test(&mi->refcnt))
2662		free(mi);
2663}
2664
2665struct mem_info *mem_info__new(void)
2666{
2667	struct mem_info *mi = zalloc(sizeof(*mi));
2668
2669	if (mi)
2670		refcount_set(&mi->refcnt, 1);
2671	return mi;
2672}
2673
2674/*
2675 * Checks that user supplied symbol kernel files are accessible because
2676 * the default mechanism for accessing elf files fails silently. i.e. if
2677 * debug syms for a build ID aren't found perf carries on normally. When
2678 * they are user supplied we should assume that the user doesn't want to
2679 * silently fail.
2680 */
2681int symbol__validate_sym_arguments(void)
2682{
2683	if (symbol_conf.vmlinux_name &&
2684	    access(symbol_conf.vmlinux_name, R_OK)) {
2685		pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
2686		return -EINVAL;
2687	}
2688	if (symbol_conf.kallsyms_name &&
2689	    access(symbol_conf.kallsyms_name, R_OK)) {
2690		pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
2691		return -EINVAL;
2692	}
2693	return 0;
2694}