tools/perf/util/symbol.c

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