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