tools/perf/util/symbol.c

   1 #include <dirent.h>
   2 #include <errno.h>
   3 #include <stdlib.h>
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <sys/param.h>
   9 #include <fcntl.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include "build-id.h"
  13 #include "util.h"
  14 #include "debug.h"
  15 #include "machine.h"
  16 #include "symbol.h"
  17 #include "strlist.h"
  18 #include "intlist.h"
  19 #include "header.h"
  20
  21 #include <elf.h>
  22 #include <limits.h>
  23 #include <symbol/kallsyms.h>
  24 #include <sys/utsname.h>
  25
  26 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
  27                                 symbol_filter_t filter);
  28 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
  29                         symbol_filter_t filter);
  30 int vmlinux_path__nr_entries;
  31 char **vmlinux_path;
  32
  33 struct symbol_conf symbol_conf = {
  34         .use_modules            = true,
  35         .try_vmlinux_path       = true,
  36         .annotate_src           = true,
  37         .demangle               = true,
  38         .demangle_kernel        = false,
  39         .cumulate_callchain     = true,
  40         .show_hist_headers      = true,
  41         .symfs                  = "",
  42         .event_group            = true,
  43 };
  44
  45 static enum dso_binary_type binary_type_symtab[] = {
  46         DSO_BINARY_TYPE__KALLSYMS,
  47         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  48         DSO_BINARY_TYPE__JAVA_JIT,
  49         DSO_BINARY_TYPE__DEBUGLINK,
  50         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  51         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  52         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  53         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  54         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  55         DSO_BINARY_TYPE__GUEST_KMODULE,
  56         DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  57         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  58         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  59         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  60         DSO_BINARY_TYPE__NOT_FOUND,
  61 };
  62
  63 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  64
  65 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  66 {
  67         symbol_type = toupper(symbol_type);
  68
  69         switch (map_type) {
  70         case MAP__FUNCTION:
  71                 return symbol_type == 'T' || symbol_type == 'W';
  72         case MAP__VARIABLE:
  73                 return symbol_type == 'D';
  74         default:
  75                 return false;
  76         }
  77 }
  78
  79 static int prefix_underscores_count(const char *str)
  80 {
  81         const char *tail = str;
  82
  83         while (*tail == '_')
  84                 tail++;
  85
  86         return tail - str;
  87 }
  88
  89 int __weak arch__choose_best_symbol(struct symbol *syma,
  90                                     struct symbol *symb __maybe_unused)
  91 {
  92         /* Avoid "SyS" kernel syscall aliases */
  93         if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
  94                 return SYMBOL_B;
  95         if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
  96                 return SYMBOL_B;
  97
  98         return SYMBOL_A;
  99 }
 100
 101 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 102 {
 103         s64 a;
 104         s64 b;
 105         size_t na, nb;
 106
 107         /* Prefer a symbol with non zero length */
 108         a = syma->end - syma->start;
 109         b = symb->end - symb->start;
 110         if ((b == 0) && (a > 0))
 111                 return SYMBOL_A;
 112         else if ((a == 0) && (b > 0))
 113                 return SYMBOL_B;
 114
 115         /* Prefer a non weak symbol over a weak one */
 116         a = syma->binding == STB_WEAK;
 117         b = symb->binding == STB_WEAK;
 118         if (b && !a)
 119                 return SYMBOL_A;
 120         if (a && !b)
 121                 return SYMBOL_B;
 122
 123         /* Prefer a global symbol over a non global one */
 124         a = syma->binding == STB_GLOBAL;
 125         b = symb->binding == STB_GLOBAL;
 126         if (a && !b)
 127                 return SYMBOL_A;
 128         if (b && !a)
 129                 return SYMBOL_B;
 130
 131         /* Prefer a symbol with less underscores */
 132         a = prefix_underscores_count(syma->name);
 133         b = prefix_underscores_count(symb->name);
 134         if (b > a)
 135                 return SYMBOL_A;
 136         else if (a > b)
 137                 return SYMBOL_B;
 138
 139         /* Choose the symbol with the longest name */
 140         na = strlen(syma->name);
 141         nb = strlen(symb->name);
 142         if (na > nb)
 143                 return SYMBOL_A;
 144         else if (na < nb)
 145                 return SYMBOL_B;
 146
 147         return arch__choose_best_symbol(syma, symb);
 148 }
 149
 150 void symbols__fixup_duplicate(struct rb_root *symbols)
 151 {
 152         struct rb_node *nd;
 153         struct symbol *curr, *next;
 154
 155         nd = rb_first(symbols);
 156
 157         while (nd) {
 158                 curr = rb_entry(nd, struct symbol, rb_node);
 159 again:
 160                 nd = rb_next(&curr->rb_node);
 161                 next = rb_entry(nd, struct symbol, rb_node);
 162
 163                 if (!nd)
 164                         break;
 165
 166                 if (curr->start != next->start)
 167                         continue;
 168
 169                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 170                         rb_erase(&next->rb_node, symbols);
 171                         symbol__delete(next);
 172                         goto again;
 173                 } else {
 174                         nd = rb_next(&curr->rb_node);
 175                         rb_erase(&curr->rb_node, symbols);
 176                         symbol__delete(curr);
 177                 }
 178         }
 179 }
 180
 181 void symbols__fixup_end(struct rb_root *symbols)
 182 {
 183         struct rb_node *nd, *prevnd = rb_first(symbols);
 184         struct symbol *curr, *prev;
 185
 186         if (prevnd == NULL)
 187                 return;
 188
 189         curr = rb_entry(prevnd, struct symbol, rb_node);
 190
 191         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 192                 prev = curr;
 193                 curr = rb_entry(nd, struct symbol, rb_node);
 194
 195                 if (prev->end == prev->start && prev->end != curr->start)
 196                         prev->end = curr->start;
 197         }
 198
 199         /* Last entry */
 200         if (curr->end == curr->start)
 201                 curr->end = roundup(curr->start, 4096);
 202 }
 203
 204 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 205 {
 206         struct maps *maps = &mg->maps[type];
 207         struct map *next, *curr;
 208
 209         pthread_rwlock_wrlock(&maps->lock);
 210
 211         curr = maps__first(maps);
 212         if (curr == NULL)
 213                 goto out_unlock;
 214
 215         for (next = map__next(curr); next; next = map__next(curr)) {
 216                 curr->end = next->start;
 217                 curr = next;
 218         }
 219
 220         /*
 221          * We still haven't the actual symbols, so guess the
 222          * last map final address.
 223          */
 224         curr->end = ~0ULL;
 225
 226 out_unlock:
 227         pthread_rwlock_unlock(&maps->lock);
 228 }
 229
 230 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 231 {
 232         size_t namelen = strlen(name) + 1;
 233         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 234                                         sizeof(*sym) + namelen));
 235         if (sym == NULL)
 236                 return NULL;
 237
 238         if (symbol_conf.priv_size)
 239                 sym = ((void *)sym) + symbol_conf.priv_size;
 240
 241         sym->start   = start;
 242         sym->end     = len ? start + len : start;
 243         sym->binding = binding;
 244         sym->namelen = namelen - 1;
 245
 246         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 247                   __func__, name, start, sym->end);
 248         memcpy(sym->name, name, namelen);
 249
 250         return sym;
 251 }
 252
 253 void symbol__delete(struct symbol *sym)
 254 {
 255         free(((void *)sym) - symbol_conf.priv_size);
 256 }
 257
 258 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 259 {
 260         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 261                        sym->start, sym->end,
 262                        sym->binding == STB_GLOBAL ? 'g' :
 263                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 264                        sym->name);
 265 }
 266
 267 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 268                                     const struct addr_location *al, FILE *fp)
 269 {
 270         unsigned long offset;
 271         size_t length;
 272
 273         if (sym && sym->name) {
 274                 length = fprintf(fp, "%s", sym->name);
 275                 if (al) {
 276                         if (al->addr < sym->end)
 277                                 offset = al->addr - sym->start;
 278                         else
 279                                 offset = al->addr - al->map->start - sym->start;
 280                         length += fprintf(fp, "+0x%lx", offset);
 281                 }
 282                 return length;
 283         } else
 284                 return fprintf(fp, "[unknown]");
 285 }
 286
 287 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 288 {
 289         return symbol__fprintf_symname_offs(sym, NULL, fp);
 290 }
 291
 292 void symbols__delete(struct rb_root *symbols)
 293 {
 294         struct symbol *pos;
 295         struct rb_node *next = rb_first(symbols);
 296
 297         while (next) {
 298                 pos = rb_entry(next, struct symbol, rb_node);
 299                 next = rb_next(&pos->rb_node);
 300                 rb_erase(&pos->rb_node, symbols);
 301                 symbol__delete(pos);
 302         }
 303 }
 304
 305 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 306 {
 307         struct rb_node **p = &symbols->rb_node;
 308         struct rb_node *parent = NULL;
 309         const u64 ip = sym->start;
 310         struct symbol *s;
 311
 312         while (*p != NULL) {
 313                 parent = *p;
 314                 s = rb_entry(parent, struct symbol, rb_node);
 315                 if (ip < s->start)
 316                         p = &(*p)->rb_left;
 317                 else
 318                         p = &(*p)->rb_right;
 319         }
 320         rb_link_node(&sym->rb_node, parent, p);
 321         rb_insert_color(&sym->rb_node, symbols);
 322 }
 323
 324 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 325 {
 326         struct rb_node *n;
 327
 328         if (symbols == NULL)
 329                 return NULL;
 330
 331         n = symbols->rb_node;
 332
 333         while (n) {
 334                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 335
 336                 if (ip < s->start)
 337                         n = n->rb_left;
 338                 else if (ip >= s->end)
 339                         n = n->rb_right;
 340                 else
 341                         return s;
 342         }
 343
 344         return NULL;
 345 }
 346
 347 static struct symbol *symbols__first(struct rb_root *symbols)
 348 {
 349         struct rb_node *n = rb_first(symbols);
 350
 351         if (n)
 352                 return rb_entry(n, struct symbol, rb_node);
 353
 354         return NULL;
 355 }
 356
 357 static struct symbol *symbols__next(struct symbol *sym)
 358 {
 359         struct rb_node *n = rb_next(&sym->rb_node);
 360
 361         if (n)
 362                 return rb_entry(n, struct symbol, rb_node);
 363
 364         return NULL;
 365 }
 366
 367 struct symbol_name_rb_node {
 368         struct rb_node  rb_node;
 369         struct symbol   sym;
 370 };
 371
 372 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 373 {
 374         struct rb_node **p = &symbols->rb_node;
 375         struct rb_node *parent = NULL;
 376         struct symbol_name_rb_node *symn, *s;
 377
 378         symn = container_of(sym, struct symbol_name_rb_node, sym);
 379
 380         while (*p != NULL) {
 381                 parent = *p;
 382                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 383                 if (strcmp(sym->name, s->sym.name) < 0)
 384                         p = &(*p)->rb_left;
 385                 else
 386                         p = &(*p)->rb_right;
 387         }
 388         rb_link_node(&symn->rb_node, parent, p);
 389         rb_insert_color(&symn->rb_node, symbols);
 390 }
 391
 392 static void symbols__sort_by_name(struct rb_root *symbols,
 393                                   struct rb_root *source)
 394 {
 395         struct rb_node *nd;
 396
 397         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 398                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 399                 symbols__insert_by_name(symbols, pos);
 400         }
 401 }
 402
 403 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 404                                             const char *name)
 405 {
 406         struct rb_node *n;
 407         struct symbol_name_rb_node *s = NULL;
 408
 409         if (symbols == NULL)
 410                 return NULL;
 411
 412         n = symbols->rb_node;
 413
 414         while (n) {
 415                 int cmp;
 416
 417                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 418                 cmp = arch__compare_symbol_names(name, s->sym.name);
 419
 420                 if (cmp < 0)
 421                         n = n->rb_left;
 422                 else if (cmp > 0)
 423                         n = n->rb_right;
 424                 else
 425                         break;
 426         }
 427
 428         if (n == NULL)
 429                 return NULL;
 430
 431         /* return first symbol that has same name (if any) */
 432         for (n = rb_prev(n); n; n = rb_prev(n)) {
 433                 struct symbol_name_rb_node *tmp;
 434
 435                 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
 436                 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
 437                         break;
 438
 439                 s = tmp;
 440         }
 441
 442         return &s->sym;
 443 }
 444
 445 void dso__reset_find_symbol_cache(struct dso *dso)
 446 {
 447         enum map_type type;
 448
 449         for (type = MAP__FUNCTION; type <= MAP__VARIABLE; ++type) {
 450                 dso->last_find_result[type].addr   = 0;
 451                 dso->last_find_result[type].symbol = NULL;
 452         }
 453 }
 454
 455 struct symbol *dso__find_symbol(struct dso *dso,
 456                                 enum map_type type, u64 addr)
 457 {
 458         if (dso->last_find_result[type].addr != addr) {
 459                 dso->last_find_result[type].addr   = addr;
 460                 dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr);
 461         }
 462
 463         return dso->last_find_result[type].symbol;
 464 }
 465
 466 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
 467 {
 468         return symbols__first(&dso->symbols[type]);
 469 }
 470
 471 struct symbol *dso__next_symbol(struct symbol *sym)
 472 {
 473         return symbols__next(sym);
 474 }
 475
 476 struct symbol *symbol__next_by_name(struct symbol *sym)
 477 {
 478         struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
 479         struct rb_node *n = rb_next(&s->rb_node);
 480
 481         return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
 482 }
 483
 484  /*
 485   * Teturns first symbol that matched with @name.
 486   */
 487 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 488                                         const char *name)
 489 {
 490         return symbols__find_by_name(&dso->symbol_names[type], name);
 491 }
 492
 493 void dso__sort_by_name(struct dso *dso, enum map_type type)
 494 {
 495         dso__set_sorted_by_name(dso, type);
 496         return symbols__sort_by_name(&dso->symbol_names[type],
 497                                      &dso->symbols[type]);
 498 }
 499
 500 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 501                                     enum map_type type, FILE *fp)
 502 {
 503         size_t ret = 0;
 504         struct rb_node *nd;
 505         struct symbol_name_rb_node *pos;
 506
 507         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 508                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 509                 fprintf(fp, "%s\n", pos->sym.name);
 510         }
 511
 512         return ret;
 513 }
 514
 515 int modules__parse(const char *filename, void *arg,
 516                    int (*process_module)(void *arg, const char *name,
 517                                          u64 start))
 518 {
 519         char *line = NULL;
 520         size_t n;
 521         FILE *file;
 522         int err = 0;
 523
 524         file = fopen(filename, "r");
 525         if (file == NULL)
 526                 return -1;
 527
 528         while (1) {
 529                 char name[PATH_MAX];
 530                 u64 start;
 531                 char *sep;
 532                 ssize_t line_len;
 533
 534                 line_len = getline(&line, &n, file);
 535                 if (line_len < 0) {
 536                         if (feof(file))
 537                                 break;
 538                         err = -1;
 539                         goto out;
 540                 }
 541
 542                 if (!line) {
 543                         err = -1;
 544                         goto out;
 545                 }
 546
 547                 line[--line_len] = '\0'; /* \n */
 548
 549                 sep = strrchr(line, 'x');
 550                 if (sep == NULL)
 551                         continue;
 552
 553                 hex2u64(sep + 1, &start);
 554
 555                 sep = strchr(line, ' ');
 556                 if (sep == NULL)
 557                         continue;
 558
 559                 *sep = '\0';
 560
 561                 scnprintf(name, sizeof(name), "[%s]", line);
 562
 563                 err = process_module(arg, name, start);
 564                 if (err)
 565                         break;
 566         }
 567 out:
 568         free(line);
 569         fclose(file);
 570         return err;
 571 }
 572
 573 struct process_kallsyms_args {
 574         struct map *map;
 575         struct dso *dso;
 576 };
 577
 578 /*
 579  * These are symbols in the kernel image, so make sure that
 580  * sym is from a kernel DSO.
 581  */
 582 bool symbol__is_idle(struct symbol *sym)
 583 {
 584         const char * const idle_symbols[] = {
 585                 "cpu_idle",
 586                 "cpu_startup_entry",
 587                 "intel_idle",
 588                 "default_idle",
 589                 "native_safe_halt",
 590                 "enter_idle",
 591                 "exit_idle",
 592                 "mwait_idle",
 593                 "mwait_idle_with_hints",
 594                 "poll_idle",
 595                 "ppc64_runlatch_off",
 596                 "pseries_dedicated_idle_sleep",
 597                 NULL
 598         };
 599
 600         int i;
 601
 602         if (!sym)
 603                 return false;
 604
 605         for (i = 0; idle_symbols[i]; i++) {
 606                 if (!strcmp(idle_symbols[i], sym->name))
 607                         return true;
 608         }
 609
 610         return false;
 611 }
 612
 613 static int map__process_kallsym_symbol(void *arg, const char *name,
 614                                        char type, u64 start)
 615 {
 616         struct symbol *sym;
 617         struct process_kallsyms_args *a = arg;
 618         struct rb_root *root = &a->dso->symbols[a->map->type];
 619
 620         if (!symbol_type__is_a(type, a->map->type))
 621                 return 0;
 622
 623         /*
 624          * module symbols are not sorted so we add all
 625          * symbols, setting length to 0, and rely on
 626          * symbols__fixup_end() to fix it up.
 627          */
 628         sym = symbol__new(start, 0, kallsyms2elf_binding(type), name);
 629         if (sym == NULL)
 630                 return -ENOMEM;
 631         /*
 632          * We will pass the symbols to the filter later, in
 633          * map__split_kallsyms, when we have split the maps per module
 634          */
 635         symbols__insert(root, sym);
 636
 637         return 0;
 638 }
 639
 640 /*
 641  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 642  * so that we can in the next step set the symbol ->end address and then
 643  * call kernel_maps__split_kallsyms.
 644  */
 645 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 646                                   struct map *map)
 647 {
 648         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 649         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 650 }
 651
 652 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
 653                                          symbol_filter_t filter)
 654 {
 655         struct map_groups *kmaps = map__kmaps(map);
 656         struct map *curr_map;
 657         struct symbol *pos;
 658         int count = 0;
 659         struct rb_root old_root = dso->symbols[map->type];
 660         struct rb_root *root = &dso->symbols[map->type];
 661         struct rb_node *next = rb_first(root);
 662
 663         if (!kmaps)
 664                 return -1;
 665
 666         *root = RB_ROOT;
 667
 668         while (next) {
 669                 char *module;
 670
 671                 pos = rb_entry(next, struct symbol, rb_node);
 672                 next = rb_next(&pos->rb_node);
 673
 674                 rb_erase_init(&pos->rb_node, &old_root);
 675
 676                 module = strchr(pos->name, '\t');
 677                 if (module)
 678                         *module = '\0';
 679
 680                 curr_map = map_groups__find(kmaps, map->type, pos->start);
 681
 682                 if (!curr_map || (filter && filter(curr_map, pos))) {
 683                         symbol__delete(pos);
 684                         continue;
 685                 }
 686
 687                 pos->start -= curr_map->start - curr_map->pgoff;
 688                 if (pos->end)
 689                         pos->end -= curr_map->start - curr_map->pgoff;
 690                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 691                 ++count;
 692         }
 693
 694         /* Symbols have been adjusted */
 695         dso->adjust_symbols = 1;
 696
 697         return count;
 698 }
 699
 700 /*
 701  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 702  * kernel range is broken in several maps, named [kernel].N, as we don't have
 703  * the original ELF section names vmlinux have.
 704  */
 705 static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
 706                                symbol_filter_t filter)
 707 {
 708         struct map_groups *kmaps = map__kmaps(map);
 709         struct machine *machine;
 710         struct map *curr_map = map;
 711         struct symbol *pos;
 712         int count = 0, moved = 0;
 713         struct rb_root *root = &dso->symbols[map->type];
 714         struct rb_node *next = rb_first(root);
 715         int kernel_range = 0;
 716
 717         if (!kmaps)
 718                 return -1;
 719
 720         machine = kmaps->machine;
 721
 722         while (next) {
 723                 char *module;
 724
 725                 pos = rb_entry(next, struct symbol, rb_node);
 726                 next = rb_next(&pos->rb_node);
 727
 728                 module = strchr(pos->name, '\t');
 729                 if (module) {
 730                         if (!symbol_conf.use_modules)
 731                                 goto discard_symbol;
 732
 733                         *module++ = '\0';
 734
 735                         if (strcmp(curr_map->dso->short_name, module)) {
 736                                 if (curr_map != map &&
 737                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 738                                     machine__is_default_guest(machine)) {
 739                                         /*
 740                                          * We assume all symbols of a module are
 741                                          * continuous in * kallsyms, so curr_map
 742                                          * points to a module and all its
 743                                          * symbols are in its kmap. Mark it as
 744                                          * loaded.
 745                                          */
 746                                         dso__set_loaded(curr_map->dso,
 747                                                         curr_map->type);
 748                                 }
 749
 750                                 curr_map = map_groups__find_by_name(kmaps,
 751                                                         map->type, module);
 752                                 if (curr_map == NULL) {
 753                                         pr_debug("%s/proc/{kallsyms,modules} "
 754                                                  "inconsistency while looking "
 755                                                  "for \"%s\" module!\n",
 756                                                  machine->root_dir, module);
 757                                         curr_map = map;
 758                                         goto discard_symbol;
 759                                 }
 760
 761                                 if (curr_map->dso->loaded &&
 762                                     !machine__is_default_guest(machine))
 763                                         goto discard_symbol;
 764                         }
 765                         /*
 766                          * So that we look just like we get from .ko files,
 767                          * i.e. not prelinked, relative to map->start.
 768                          */
 769                         pos->start = curr_map->map_ip(curr_map, pos->start);
 770                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 771                 } else if (curr_map != map) {
 772                         char dso_name[PATH_MAX];
 773                         struct dso *ndso;
 774
 775                         if (delta) {
 776                                 /* Kernel was relocated at boot time */
 777                                 pos->start -= delta;
 778                                 pos->end -= delta;
 779                         }
 780
 781                         if (count == 0) {
 782                                 curr_map = map;
 783                                 goto filter_symbol;
 784                         }
 785
 786                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 787                                 snprintf(dso_name, sizeof(dso_name),
 788                                         "[guest.kernel].%d",
 789                                         kernel_range++);
 790                         else
 791                                 snprintf(dso_name, sizeof(dso_name),
 792                                         "[kernel].%d",
 793                                         kernel_range++);
 794
 795                         ndso = dso__new(dso_name);
 796                         if (ndso == NULL)
 797                                 return -1;
 798
 799                         ndso->kernel = dso->kernel;
 800
 801                         curr_map = map__new2(pos->start, ndso, map->type);
 802                         if (curr_map == NULL) {
 803                                 dso__put(ndso);
 804                                 return -1;
 805                         }
 806
 807                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 808                         map_groups__insert(kmaps, curr_map);
 809                         ++kernel_range;
 810                 } else if (delta) {
 811                         /* Kernel was relocated at boot time */
 812                         pos->start -= delta;
 813                         pos->end -= delta;
 814                 }
 815 filter_symbol:
 816                 if (filter && filter(curr_map, pos)) {
 817 discard_symbol:         rb_erase(&pos->rb_node, root);
 818                         symbol__delete(pos);
 819                 } else {
 820                         if (curr_map != map) {
 821                                 rb_erase(&pos->rb_node, root);
 822                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 823                                 ++moved;
 824                         } else
 825                                 ++count;
 826                 }
 827         }
 828
 829         if (curr_map != map &&
 830             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 831             machine__is_default_guest(kmaps->machine)) {
 832                 dso__set_loaded(curr_map->dso, curr_map->type);
 833         }
 834
 835         return count + moved;
 836 }
 837
 838 bool symbol__restricted_filename(const char *filename,
 839                                  const char *restricted_filename)
 840 {
 841         bool restricted = false;
 842
 843         if (symbol_conf.kptr_restrict) {
 844                 char *r = realpath(filename, NULL);
 845
 846                 if (r != NULL) {
 847                         restricted = strcmp(r, restricted_filename) == 0;
 848                         free(r);
 849                         return restricted;
 850                 }
 851         }
 852
 853         return restricted;
 854 }
 855
 856 struct module_info {
 857         struct rb_node rb_node;
 858         char *name;
 859         u64 start;
 860 };
 861
 862 static void add_module(struct module_info *mi, struct rb_root *modules)
 863 {
 864         struct rb_node **p = &modules->rb_node;
 865         struct rb_node *parent = NULL;
 866         struct module_info *m;
 867
 868         while (*p != NULL) {
 869                 parent = *p;
 870                 m = rb_entry(parent, struct module_info, rb_node);
 871                 if (strcmp(mi->name, m->name) < 0)
 872                         p = &(*p)->rb_left;
 873                 else
 874                         p = &(*p)->rb_right;
 875         }
 876         rb_link_node(&mi->rb_node, parent, p);
 877         rb_insert_color(&mi->rb_node, modules);
 878 }
 879
 880 static void delete_modules(struct rb_root *modules)
 881 {
 882         struct module_info *mi;
 883         struct rb_node *next = rb_first(modules);
 884
 885         while (next) {
 886                 mi = rb_entry(next, struct module_info, rb_node);
 887                 next = rb_next(&mi->rb_node);
 888                 rb_erase(&mi->rb_node, modules);
 889                 zfree(&mi->name);
 890                 free(mi);
 891         }
 892 }
 893
 894 static struct module_info *find_module(const char *name,
 895                                        struct rb_root *modules)
 896 {
 897         struct rb_node *n = modules->rb_node;
 898
 899         while (n) {
 900                 struct module_info *m;
 901                 int cmp;
 902
 903                 m = rb_entry(n, struct module_info, rb_node);
 904                 cmp = strcmp(name, m->name);
 905                 if (cmp < 0)
 906                         n = n->rb_left;
 907                 else if (cmp > 0)
 908                         n = n->rb_right;
 909                 else
 910                         return m;
 911         }
 912
 913         return NULL;
 914 }
 915
 916 static int __read_proc_modules(void *arg, const char *name, u64 start)
 917 {
 918         struct rb_root *modules = arg;
 919         struct module_info *mi;
 920
 921         mi = zalloc(sizeof(struct module_info));
 922         if (!mi)
 923                 return -ENOMEM;
 924
 925         mi->name = strdup(name);
 926         mi->start = start;
 927
 928         if (!mi->name) {
 929                 free(mi);
 930                 return -ENOMEM;
 931         }
 932
 933         add_module(mi, modules);
 934
 935         return 0;
 936 }
 937
 938 static int read_proc_modules(const char *filename, struct rb_root *modules)
 939 {
 940         if (symbol__restricted_filename(filename, "/proc/modules"))
 941                 return -1;
 942
 943         if (modules__parse(filename, modules, __read_proc_modules)) {
 944                 delete_modules(modules);
 945                 return -1;
 946         }
 947
 948         return 0;
 949 }
 950
 951 int compare_proc_modules(const char *from, const char *to)
 952 {
 953         struct rb_root from_modules = RB_ROOT;
 954         struct rb_root to_modules = RB_ROOT;
 955         struct rb_node *from_node, *to_node;
 956         struct module_info *from_m, *to_m;
 957         int ret = -1;
 958
 959         if (read_proc_modules(from, &from_modules))
 960                 return -1;
 961
 962         if (read_proc_modules(to, &to_modules))
 963                 goto out_delete_from;
 964
 965         from_node = rb_first(&from_modules);
 966         to_node = rb_first(&to_modules);
 967         while (from_node) {
 968                 if (!to_node)
 969                         break;
 970
 971                 from_m = rb_entry(from_node, struct module_info, rb_node);
 972                 to_m = rb_entry(to_node, struct module_info, rb_node);
 973
 974                 if (from_m->start != to_m->start ||
 975                     strcmp(from_m->name, to_m->name))
 976                         break;
 977
 978                 from_node = rb_next(from_node);
 979                 to_node = rb_next(to_node);
 980         }
 981
 982         if (!from_node && !to_node)
 983                 ret = 0;
 984
 985         delete_modules(&to_modules);
 986 out_delete_from:
 987         delete_modules(&from_modules);
 988
 989         return ret;
 990 }
 991
 992 static int do_validate_kcore_modules(const char *filename, struct map *map,
 993                                   struct map_groups *kmaps)
 994 {
 995         struct rb_root modules = RB_ROOT;
 996         struct map *old_map;
 997         int err;
 998
 999         err = read_proc_modules(filename, &modules);
1000         if (err)
1001                 return err;
1002
1003         old_map = map_groups__first(kmaps, map->type);
1004         while (old_map) {
1005                 struct map *next = map_groups__next(old_map);
1006                 struct module_info *mi;
1007
1008                 if (old_map == map || old_map->start == map->start) {
1009                         /* The kernel map */
1010                         old_map = next;
1011                         continue;
1012                 }
1013
1014                 /* Module must be in memory at the same address */
1015                 mi = find_module(old_map->dso->short_name, &modules);
1016                 if (!mi || mi->start != old_map->start) {
1017                         err = -EINVAL;
1018                         goto out;
1019                 }
1020
1021                 old_map = next;
1022         }
1023 out:
1024         delete_modules(&modules);
1025         return err;
1026 }
1027
1028 /*
1029  * If kallsyms is referenced by name then we look for filename in the same
1030  * directory.
1031  */
1032 static bool filename_from_kallsyms_filename(char *filename,
1033                                             const char *base_name,
1034                                             const char *kallsyms_filename)
1035 {
1036         char *name;
1037
1038         strcpy(filename, kallsyms_filename);
1039         name = strrchr(filename, '/');
1040         if (!name)
1041                 return false;
1042
1043         name += 1;
1044
1045         if (!strcmp(name, "kallsyms")) {
1046                 strcpy(name, base_name);
1047                 return true;
1048         }
1049
1050         return false;
1051 }
1052
1053 static int validate_kcore_modules(const char *kallsyms_filename,
1054                                   struct map *map)
1055 {
1056         struct map_groups *kmaps = map__kmaps(map);
1057         char modules_filename[PATH_MAX];
1058
1059         if (!kmaps)
1060                 return -EINVAL;
1061
1062         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1063                                              kallsyms_filename))
1064                 return -EINVAL;
1065
1066         if (do_validate_kcore_modules(modules_filename, map, kmaps))
1067                 return -EINVAL;
1068
1069         return 0;
1070 }
1071
1072 static int validate_kcore_addresses(const char *kallsyms_filename,
1073                                     struct map *map)
1074 {
1075         struct kmap *kmap = map__kmap(map);
1076
1077         if (!kmap)
1078                 return -EINVAL;
1079
1080         if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1081                 u64 start;
1082
1083                 start = kallsyms__get_function_start(kallsyms_filename,
1084                                                      kmap->ref_reloc_sym->name);
1085                 if (start != kmap->ref_reloc_sym->addr)
1086                         return -EINVAL;
1087         }
1088
1089         return validate_kcore_modules(kallsyms_filename, map);
1090 }
1091
1092 struct kcore_mapfn_data {
1093         struct dso *dso;
1094         enum map_type type;
1095         struct list_head maps;
1096 };
1097
1098 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1099 {
1100         struct kcore_mapfn_data *md = data;
1101         struct map *map;
1102
1103         map = map__new2(start, md->dso, md->type);
1104         if (map == NULL)
1105                 return -ENOMEM;
1106
1107         map->end = map->start + len;
1108         map->pgoff = pgoff;
1109
1110         list_add(&map->node, &md->maps);
1111
1112         return 0;
1113 }
1114
1115 static int dso__load_kcore(struct dso *dso, struct map *map,
1116                            const char *kallsyms_filename)
1117 {
1118         struct map_groups *kmaps = map__kmaps(map);
1119         struct machine *machine;
1120         struct kcore_mapfn_data md;
1121         struct map *old_map, *new_map, *replacement_map = NULL;
1122         bool is_64_bit;
1123         int err, fd;
1124         char kcore_filename[PATH_MAX];
1125         struct symbol *sym;
1126
1127         if (!kmaps)
1128                 return -EINVAL;
1129
1130         machine = kmaps->machine;
1131
1132         /* This function requires that the map is the kernel map */
1133         if (map != machine->vmlinux_maps[map->type])
1134                 return -EINVAL;
1135
1136         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1137                                              kallsyms_filename))
1138                 return -EINVAL;
1139
1140         /* Modules and kernel must be present at their original addresses */
1141         if (validate_kcore_addresses(kallsyms_filename, map))
1142                 return -EINVAL;
1143
1144         md.dso = dso;
1145         md.type = map->type;
1146         INIT_LIST_HEAD(&md.maps);
1147
1148         fd = open(kcore_filename, O_RDONLY);
1149         if (fd < 0) {
1150                 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1151                          kcore_filename);
1152                 return -EINVAL;
1153         }
1154
1155         /* Read new maps into temporary lists */
1156         err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1157                               &is_64_bit);
1158         if (err)
1159                 goto out_err;
1160         dso->is_64_bit = is_64_bit;
1161
1162         if (list_empty(&md.maps)) {
1163                 err = -EINVAL;
1164                 goto out_err;
1165         }
1166
1167         /* Remove old maps */
1168         old_map = map_groups__first(kmaps, map->type);
1169         while (old_map) {
1170                 struct map *next = map_groups__next(old_map);
1171
1172                 if (old_map != map)
1173                         map_groups__remove(kmaps, old_map);
1174                 old_map = next;
1175         }
1176
1177         /* Find the kernel map using the first symbol */
1178         sym = dso__first_symbol(dso, map->type);
1179         list_for_each_entry(new_map, &md.maps, node) {
1180                 if (sym && sym->start >= new_map->start &&
1181                     sym->start < new_map->end) {
1182                         replacement_map = new_map;
1183                         break;
1184                 }
1185         }
1186
1187         if (!replacement_map)
1188                 replacement_map = list_entry(md.maps.next, struct map, node);
1189
1190         /* Add new maps */
1191         while (!list_empty(&md.maps)) {
1192                 new_map = list_entry(md.maps.next, struct map, node);
1193                 list_del_init(&new_map->node);
1194                 if (new_map == replacement_map) {
1195                         map->start      = new_map->start;
1196                         map->end        = new_map->end;
1197                         map->pgoff      = new_map->pgoff;
1198                         map->map_ip     = new_map->map_ip;
1199                         map->unmap_ip   = new_map->unmap_ip;
1200                         /* Ensure maps are correctly ordered */
1201                         map__get(map);
1202                         map_groups__remove(kmaps, map);
1203                         map_groups__insert(kmaps, map);
1204                         map__put(map);
1205                 } else {
1206                         map_groups__insert(kmaps, new_map);
1207                 }
1208
1209                 map__put(new_map);
1210         }
1211
1212         /*
1213          * Set the data type and long name so that kcore can be read via
1214          * dso__data_read_addr().
1215          */
1216         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1217                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1218         else
1219                 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1220         dso__set_long_name(dso, strdup(kcore_filename), true);
1221
1222         close(fd);
1223
1224         if (map->type == MAP__FUNCTION)
1225                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1226         else
1227                 pr_debug("Using %s for kernel data\n", kcore_filename);
1228
1229         return 0;
1230
1231 out_err:
1232         while (!list_empty(&md.maps)) {
1233                 map = list_entry(md.maps.next, struct map, node);
1234                 list_del_init(&map->node);
1235                 map__put(map);
1236         }
1237         close(fd);
1238         return -EINVAL;
1239 }
1240
1241 /*
1242  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1243  * delta based on the relocation reference symbol.
1244  */
1245 static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
1246 {
1247         struct kmap *kmap = map__kmap(map);
1248         u64 addr;
1249
1250         if (!kmap)
1251                 return -1;
1252
1253         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1254                 return 0;
1255
1256         addr = kallsyms__get_function_start(filename,
1257                                             kmap->ref_reloc_sym->name);
1258         if (!addr)
1259                 return -1;
1260
1261         *delta = addr - kmap->ref_reloc_sym->addr;
1262         return 0;
1263 }
1264
1265 int dso__load_kallsyms(struct dso *dso, const char *filename,
1266                        struct map *map, symbol_filter_t filter)
1267 {
1268         u64 delta = 0;
1269
1270         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1271                 return -1;
1272
1273         if (dso__load_all_kallsyms(dso, filename, map) < 0)
1274                 return -1;
1275
1276         if (kallsyms__delta(map, filename, &delta))
1277                 return -1;
1278
1279         symbols__fixup_duplicate(&dso->symbols[map->type]);
1280         symbols__fixup_end(&dso->symbols[map->type]);
1281
1282         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1283                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1284         else
1285                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1286
1287         if (!dso__load_kcore(dso, map, filename))
1288                 return dso__split_kallsyms_for_kcore(dso, map, filter);
1289         else
1290                 return dso__split_kallsyms(dso, map, delta, filter);
1291 }
1292
1293 static int dso__load_perf_map(struct dso *dso, struct map *map,
1294                               symbol_filter_t filter)
1295 {
1296         char *line = NULL;
1297         size_t n;
1298         FILE *file;
1299         int nr_syms = 0;
1300
1301         file = fopen(dso->long_name, "r");
1302         if (file == NULL)
1303                 goto out_failure;
1304
1305         while (!feof(file)) {
1306                 u64 start, size;
1307                 struct symbol *sym;
1308                 int line_len, len;
1309
1310                 line_len = getline(&line, &n, file);
1311                 if (line_len < 0)
1312                         break;
1313
1314                 if (!line)
1315                         goto out_failure;
1316
1317                 line[--line_len] = '\0'; /* \n */
1318
1319                 len = hex2u64(line, &start);
1320
1321                 len++;
1322                 if (len + 2 >= line_len)
1323                         continue;
1324
1325                 len += hex2u64(line + len, &size);
1326
1327                 len++;
1328                 if (len + 2 >= line_len)
1329                         continue;
1330
1331                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
1332
1333                 if (sym == NULL)
1334                         goto out_delete_line;
1335
1336                 if (filter && filter(map, sym))
1337                         symbol__delete(sym);
1338                 else {
1339                         symbols__insert(&dso->symbols[map->type], sym);
1340                         nr_syms++;
1341                 }
1342         }
1343
1344         free(line);
1345         fclose(file);
1346
1347         return nr_syms;
1348
1349 out_delete_line:
1350         free(line);
1351 out_failure:
1352         return -1;
1353 }
1354
1355 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1356                                            enum dso_binary_type type)
1357 {
1358         switch (type) {
1359         case DSO_BINARY_TYPE__JAVA_JIT:
1360         case DSO_BINARY_TYPE__DEBUGLINK:
1361         case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1362         case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1363         case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1364         case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1365         case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1366                 return !kmod && dso->kernel == DSO_TYPE_USER;
1367
1368         case DSO_BINARY_TYPE__KALLSYMS:
1369         case DSO_BINARY_TYPE__VMLINUX:
1370         case DSO_BINARY_TYPE__KCORE:
1371                 return dso->kernel == DSO_TYPE_KERNEL;
1372
1373         case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1374         case DSO_BINARY_TYPE__GUEST_VMLINUX:
1375         case DSO_BINARY_TYPE__GUEST_KCORE:
1376                 return dso->kernel == DSO_TYPE_GUEST_KERNEL;
1377
1378         case DSO_BINARY_TYPE__GUEST_KMODULE:
1379         case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1380         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1381         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1382                 /*
1383                  * kernel modules know their symtab type - it's set when
1384                  * creating a module dso in machine__findnew_module_map().
1385                  */
1386                 return kmod && dso->symtab_type == type;
1387
1388         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1389                 return true;
1390
1391         case DSO_BINARY_TYPE__NOT_FOUND:
1392         default:
1393                 return false;
1394         }
1395 }
1396
1397 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1398 {
1399         char *name;
1400         int ret = -1;
1401         u_int i;
1402         struct machine *machine;
1403         char *root_dir = (char *) "";
1404         int ss_pos = 0;
1405         struct symsrc ss_[2];
1406         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1407         bool kmod;
1408         unsigned char build_id[BUILD_ID_SIZE];
1409
1410         pthread_mutex_lock(&dso->lock);
1411
1412         /* check again under the dso->lock */
1413         if (dso__loaded(dso, map->type)) {
1414                 ret = 1;
1415                 goto out;
1416         }
1417
1418         if (dso->kernel) {
1419                 if (dso->kernel == DSO_TYPE_KERNEL)
1420                         ret = dso__load_kernel_sym(dso, map, filter);
1421                 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1422                         ret = dso__load_guest_kernel_sym(dso, map, filter);
1423
1424                 goto out;
1425         }
1426
1427         if (map->groups && map->groups->machine)
1428                 machine = map->groups->machine;
1429         else
1430                 machine = NULL;
1431
1432         dso->adjust_symbols = 0;
1433
1434         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1435                 struct stat st;
1436
1437                 if (lstat(dso->name, &st) < 0)
1438                         goto out;
1439
1440                 if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
1441                         pr_warning("File %s not owned by current user or root, "
1442                                    "ignoring it (use -f to override).\n", dso->name);
1443                         goto out;
1444                 }
1445
1446                 ret = dso__load_perf_map(dso, map, filter);
1447                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1448                                              DSO_BINARY_TYPE__NOT_FOUND;
1449                 goto out;
1450         }
1451
1452         if (machine)
1453                 root_dir = machine->root_dir;
1454
1455         name = malloc(PATH_MAX);
1456         if (!name)
1457                 goto out;
1458
1459         kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1460                 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1461                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1462                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1463
1464
1465         /*
1466          * Read the build id if possible. This is required for
1467          * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1468          */
1469         if (filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0)
1470                 dso__set_build_id(dso, build_id);
1471
1472         /*
1473          * Iterate over candidate debug images.
1474          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1475          * and/or opd section) for processing.
1476          */
1477         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1478                 struct symsrc *ss = &ss_[ss_pos];
1479                 bool next_slot = false;
1480
1481                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1482
1483                 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1484                         continue;
1485
1486                 if (dso__read_binary_type_filename(dso, symtab_type,
1487                                                    root_dir, name, PATH_MAX))
1488                         continue;
1489
1490                 /* Name is now the name of the next image to try */
1491                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
1492                         continue;
1493
1494                 if (!syms_ss && symsrc__has_symtab(ss)) {
1495                         syms_ss = ss;
1496                         next_slot = true;
1497                         if (!dso->symsrc_filename)
1498                                 dso->symsrc_filename = strdup(name);
1499                 }
1500
1501                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1502                         runtime_ss = ss;
1503                         next_slot = true;
1504                 }
1505
1506                 if (next_slot) {
1507                         ss_pos++;
1508
1509                         if (syms_ss && runtime_ss)
1510                                 break;
1511                 } else {
1512                         symsrc__destroy(ss);
1513                 }
1514
1515         }
1516
1517         if (!runtime_ss && !syms_ss)
1518                 goto out_free;
1519
1520         if (runtime_ss && !syms_ss) {
1521                 syms_ss = runtime_ss;
1522         }
1523
1524         /* We'll have to hope for the best */
1525         if (!runtime_ss && syms_ss)
1526                 runtime_ss = syms_ss;
1527
1528         if (syms_ss)
1529                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, kmod);
1530         else
1531                 ret = -1;
1532
1533         if (ret > 0) {
1534                 int nr_plt;
1535
1536                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1537                 if (nr_plt > 0)
1538                         ret += nr_plt;
1539         }
1540
1541         for (; ss_pos > 0; ss_pos--)
1542                 symsrc__destroy(&ss_[ss_pos - 1]);
1543 out_free:
1544         free(name);
1545         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1546                 ret = 0;
1547 out:
1548         dso__set_loaded(dso, map->type);
1549         pthread_mutex_unlock(&dso->lock);
1550
1551         return ret;
1552 }
1553
1554 struct map *map_groups__find_by_name(struct map_groups *mg,
1555                                      enum map_type type, const char *name)
1556 {
1557         struct maps *maps = &mg->maps[type];
1558         struct map *map;
1559
1560         pthread_rwlock_rdlock(&maps->lock);
1561
1562         for (map = maps__first(maps); map; map = map__next(map)) {
1563                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1564                         goto out_unlock;
1565         }
1566
1567         map = NULL;
1568
1569 out_unlock:
1570         pthread_rwlock_unlock(&maps->lock);
1571         return map;
1572 }
1573
1574 int dso__load_vmlinux(struct dso *dso, struct map *map,
1575                       const char *vmlinux, bool vmlinux_allocated,
1576                       symbol_filter_t filter)
1577 {
1578         int err = -1;
1579         struct symsrc ss;
1580         char symfs_vmlinux[PATH_MAX];
1581         enum dso_binary_type symtab_type;
1582
1583         if (vmlinux[0] == '/')
1584                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1585         else
1586                 symbol__join_symfs(symfs_vmlinux, vmlinux);
1587
1588         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1589                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1590         else
1591                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1592
1593         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1594                 return -1;
1595
1596         err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1597         symsrc__destroy(&ss);
1598
1599         if (err > 0) {
1600                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1601                         dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1602                 else
1603                         dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1604                 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1605                 dso__set_loaded(dso, map->type);
1606                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1607         }
1608
1609         return err;
1610 }
1611
1612 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1613                            symbol_filter_t filter)
1614 {
1615         int i, err = 0;
1616         char *filename = NULL;
1617
1618         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1619                  vmlinux_path__nr_entries + 1);
1620
1621         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1622                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
1623                 if (err > 0)
1624                         goto out;
1625         }
1626
1627         if (!symbol_conf.ignore_vmlinux_buildid)
1628                 filename = dso__build_id_filename(dso, NULL, 0);
1629         if (filename != NULL) {
1630                 err = dso__load_vmlinux(dso, map, filename, true, filter);
1631                 if (err > 0)
1632                         goto out;
1633                 free(filename);
1634         }
1635 out:
1636         return err;
1637 }
1638
1639 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1640 {
1641         char kallsyms_filename[PATH_MAX];
1642         struct dirent *dent;
1643         int ret = -1;
1644         DIR *d;
1645
1646         d = opendir(dir);
1647         if (!d)
1648                 return -1;
1649
1650         while (1) {
1651                 dent = readdir(d);
1652                 if (!dent)
1653                         break;
1654                 if (dent->d_type != DT_DIR)
1655                         continue;
1656                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1657                           "%s/%s/kallsyms", dir, dent->d_name);
1658                 if (!validate_kcore_addresses(kallsyms_filename, map)) {
1659                         strlcpy(dir, kallsyms_filename, dir_sz);
1660                         ret = 0;
1661                         break;
1662                 }
1663         }
1664
1665         closedir(d);
1666
1667         return ret;
1668 }
1669
1670 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1671 {
1672         u8 host_build_id[BUILD_ID_SIZE];
1673         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1674         bool is_host = false;
1675         char path[PATH_MAX];
1676
1677         if (!dso->has_build_id) {
1678                 /*
1679                  * Last resort, if we don't have a build-id and couldn't find
1680                  * any vmlinux file, try the running kernel kallsyms table.
1681                  */
1682                 goto proc_kallsyms;
1683         }
1684
1685         if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1686                                  sizeof(host_build_id)) == 0)
1687                 is_host = dso__build_id_equal(dso, host_build_id);
1688
1689         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1690
1691         scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
1692                   sbuild_id);
1693
1694         /* Use /proc/kallsyms if possible */
1695         if (is_host) {
1696                 DIR *d;
1697                 int fd;
1698
1699                 /* If no cached kcore go with /proc/kallsyms */
1700                 d = opendir(path);
1701                 if (!d)
1702                         goto proc_kallsyms;
1703                 closedir(d);
1704
1705                 /*
1706                  * Do not check the build-id cache, until we know we cannot use
1707                  * /proc/kcore.
1708                  */
1709                 fd = open("/proc/kcore", O_RDONLY);
1710                 if (fd != -1) {
1711                         close(fd);
1712                         /* If module maps match go with /proc/kallsyms */
1713                         if (!validate_kcore_addresses("/proc/kallsyms", map))
1714                                 goto proc_kallsyms;
1715                 }
1716
1717                 /* Find kallsyms in build-id cache with kcore */
1718                 if (!find_matching_kcore(map, path, sizeof(path)))
1719                         return strdup(path);
1720
1721                 goto proc_kallsyms;
1722         }
1723
1724         /* Find kallsyms in build-id cache with kcore */
1725         if (!find_matching_kcore(map, path, sizeof(path)))
1726                 return strdup(path);
1727
1728         scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
1729                   buildid_dir, sbuild_id);
1730
1731         if (access(path, F_OK)) {
1732                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1733                        sbuild_id);
1734                 return NULL;
1735         }
1736
1737         return strdup(path);
1738
1739 proc_kallsyms:
1740         return strdup("/proc/kallsyms");
1741 }
1742
1743 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1744                                 symbol_filter_t filter)
1745 {
1746         int err;
1747         const char *kallsyms_filename = NULL;
1748         char *kallsyms_allocated_filename = NULL;
1749         /*
1750          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1751          * it and only it, reporting errors to the user if it cannot be used.
1752          *
1753          * For instance, try to analyse an ARM perf.data file _without_ a
1754          * build-id, or if the user specifies the wrong path to the right
1755          * vmlinux file, obviously we can't fallback to another vmlinux (a
1756          * x86_86 one, on the machine where analysis is being performed, say),
1757          * or worse, /proc/kallsyms.
1758          *
1759          * If the specified file _has_ a build-id and there is a build-id
1760          * section in the perf.data file, we will still do the expected
1761          * validation in dso__load_vmlinux and will bail out if they don't
1762          * match.
1763          */
1764         if (symbol_conf.kallsyms_name != NULL) {
1765                 kallsyms_filename = symbol_conf.kallsyms_name;
1766                 goto do_kallsyms;
1767         }
1768
1769         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1770                 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
1771                                          false, filter);
1772         }
1773
1774         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1775                 err = dso__load_vmlinux_path(dso, map, filter);
1776                 if (err > 0)
1777                         return err;
1778         }
1779
1780         /* do not try local files if a symfs was given */
1781         if (symbol_conf.symfs[0] != 0)
1782                 return -1;
1783
1784         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1785         if (!kallsyms_allocated_filename)
1786                 return -1;
1787
1788         kallsyms_filename = kallsyms_allocated_filename;
1789
1790 do_kallsyms:
1791         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1792         if (err > 0)
1793                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1794         free(kallsyms_allocated_filename);
1795
1796         if (err > 0 && !dso__is_kcore(dso)) {
1797                 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
1798                 dso__set_long_name(dso, "[kernel.kallsyms]", false);
1799                 map__fixup_start(map);
1800                 map__fixup_end(map);
1801         }
1802
1803         return err;
1804 }
1805
1806 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1807                                       symbol_filter_t filter)
1808 {
1809         int err;
1810         const char *kallsyms_filename = NULL;
1811         struct machine *machine;
1812         char path[PATH_MAX];
1813
1814         if (!map->groups) {
1815                 pr_debug("Guest kernel map hasn't the point to groups\n");
1816                 return -1;
1817         }
1818         machine = map->groups->machine;
1819
1820         if (machine__is_default_guest(machine)) {
1821                 /*
1822                  * if the user specified a vmlinux filename, use it and only
1823                  * it, reporting errors to the user if it cannot be used.
1824                  * Or use file guest_kallsyms inputted by user on commandline
1825                  */
1826                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1827                         err = dso__load_vmlinux(dso, map,
1828                                                 symbol_conf.default_guest_vmlinux_name,
1829                                                 false, filter);
1830                         return err;
1831                 }
1832
1833                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1834                 if (!kallsyms_filename)
1835                         return -1;
1836         } else {
1837                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1838                 kallsyms_filename = path;
1839         }
1840
1841         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1842         if (err > 0)
1843                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1844         if (err > 0 && !dso__is_kcore(dso)) {
1845                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1846                 machine__mmap_name(machine, path, sizeof(path));
1847                 dso__set_long_name(dso, strdup(path), true);
1848                 map__fixup_start(map);
1849                 map__fixup_end(map);
1850         }
1851
1852         return err;
1853 }
1854
1855 static void vmlinux_path__exit(void)
1856 {
1857         while (--vmlinux_path__nr_entries >= 0)
1858                 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1859         vmlinux_path__nr_entries = 0;
1860
1861         zfree(&vmlinux_path);
1862 }
1863
1864 static const char * const vmlinux_paths[] = {
1865         "vmlinux",
1866         "/boot/vmlinux"
1867 };
1868
1869 static const char * const vmlinux_paths_upd[] = {
1870         "/boot/vmlinux-%s",
1871         "/usr/lib/debug/boot/vmlinux-%s",
1872         "/lib/modules/%s/build/vmlinux",
1873         "/usr/lib/debug/lib/modules/%s/vmlinux",
1874         "/usr/lib/debug/boot/vmlinux-%s.debug"
1875 };
1876
1877 static int vmlinux_path__add(const char *new_entry)
1878 {
1879         vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
1880         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1881                 return -1;
1882         ++vmlinux_path__nr_entries;
1883
1884         return 0;
1885 }
1886
1887 static int vmlinux_path__init(struct perf_env *env)
1888 {
1889         struct utsname uts;
1890         char bf[PATH_MAX];
1891         char *kernel_version;
1892         unsigned int i;
1893
1894         vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
1895                               ARRAY_SIZE(vmlinux_paths_upd)));
1896         if (vmlinux_path == NULL)
1897                 return -1;
1898
1899         for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
1900                 if (vmlinux_path__add(vmlinux_paths[i]) < 0)
1901                         goto out_fail;
1902
1903         /* only try kernel version if no symfs was given */
1904         if (symbol_conf.symfs[0] != 0)
1905                 return 0;
1906
1907         if (env) {
1908                 kernel_version = env->os_release;
1909         } else {
1910                 if (uname(&uts) < 0)
1911                         goto out_fail;
1912
1913                 kernel_version = uts.release;
1914         }
1915
1916         for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
1917                 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
1918                 if (vmlinux_path__add(bf) < 0)
1919                         goto out_fail;
1920         }
1921
1922         return 0;
1923
1924 out_fail:
1925         vmlinux_path__exit();
1926         return -1;
1927 }
1928
1929 int setup_list(struct strlist **list, const char *list_str,
1930                       const char *list_name)
1931 {
1932         if (list_str == NULL)
1933                 return 0;
1934
1935         *list = strlist__new(list_str, NULL);
1936         if (!*list) {
1937                 pr_err("problems parsing %s list\n", list_name);
1938                 return -1;
1939         }
1940
1941         symbol_conf.has_filter = true;
1942         return 0;
1943 }
1944
1945 int setup_intlist(struct intlist **list, const char *list_str,
1946                   const char *list_name)
1947 {
1948         if (list_str == NULL)
1949                 return 0;
1950
1951         *list = intlist__new(list_str);
1952         if (!*list) {
1953                 pr_err("problems parsing %s list\n", list_name);
1954                 return -1;
1955         }
1956         return 0;
1957 }
1958
1959 static bool symbol__read_kptr_restrict(void)
1960 {
1961         bool value = false;
1962
1963         if (geteuid() != 0) {
1964                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1965                 if (fp != NULL) {
1966                         char line[8];
1967
1968                         if (fgets(line, sizeof(line), fp) != NULL)
1969                                 value = atoi(line) != 0;
1970
1971                         fclose(fp);
1972                 }
1973         }
1974
1975         return value;
1976 }
1977
1978 int symbol__init(struct perf_env *env)
1979 {
1980         const char *symfs;
1981
1982         if (symbol_conf.initialized)
1983                 return 0;
1984
1985         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1986
1987         symbol__elf_init();
1988
1989         if (symbol_conf.sort_by_name)
1990                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1991                                           sizeof(struct symbol));
1992
1993         if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
1994                 return -1;
1995
1996         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1997                 pr_err("'.' is the only non valid --field-separator argument\n");
1998                 return -1;
1999         }
2000
2001         if (setup_list(&symbol_conf.dso_list,
2002                        symbol_conf.dso_list_str, "dso") < 0)
2003                 return -1;
2004
2005         if (setup_list(&symbol_conf.comm_list,
2006                        symbol_conf.comm_list_str, "comm") < 0)
2007                 goto out_free_dso_list;
2008
2009         if (setup_intlist(&symbol_conf.pid_list,
2010                        symbol_conf.pid_list_str, "pid") < 0)
2011                 goto out_free_comm_list;
2012
2013         if (setup_intlist(&symbol_conf.tid_list,
2014                        symbol_conf.tid_list_str, "tid") < 0)
2015                 goto out_free_pid_list;
2016
2017         if (setup_list(&symbol_conf.sym_list,
2018                        symbol_conf.sym_list_str, "symbol") < 0)
2019                 goto out_free_tid_list;
2020
2021         /*
2022          * A path to symbols of "/" is identical to ""
2023          * reset here for simplicity.
2024          */
2025         symfs = realpath(symbol_conf.symfs, NULL);
2026         if (symfs == NULL)
2027                 symfs = symbol_conf.symfs;
2028         if (strcmp(symfs, "/") == 0)
2029                 symbol_conf.symfs = "";
2030         if (symfs != symbol_conf.symfs)
2031                 free((void *)symfs);
2032
2033         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2034
2035         symbol_conf.initialized = true;
2036         return 0;
2037
2038 out_free_tid_list:
2039         intlist__delete(symbol_conf.tid_list);
2040 out_free_pid_list:
2041         intlist__delete(symbol_conf.pid_list);
2042 out_free_comm_list:
2043         strlist__delete(symbol_conf.comm_list);
2044 out_free_dso_list:
2045         strlist__delete(symbol_conf.dso_list);
2046         return -1;
2047 }
2048
2049 void symbol__exit(void)
2050 {
2051         if (!symbol_conf.initialized)
2052                 return;
2053         strlist__delete(symbol_conf.sym_list);
2054         strlist__delete(symbol_conf.dso_list);
2055         strlist__delete(symbol_conf.comm_list);
2056         intlist__delete(symbol_conf.tid_list);
2057         intlist__delete(symbol_conf.pid_list);
2058         vmlinux_path__exit();
2059         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2060         symbol_conf.initialized = false;
2061 }