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 };
  43
  44 static enum dso_binary_type binary_type_symtab[] = {
  45         DSO_BINARY_TYPE__KALLSYMS,
  46         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  47         DSO_BINARY_TYPE__JAVA_JIT,
  48         DSO_BINARY_TYPE__DEBUGLINK,
  49         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  50         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  51         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  52         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  53         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  54         DSO_BINARY_TYPE__GUEST_KMODULE,
  55         DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  56         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  57         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  58         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  59         DSO_BINARY_TYPE__NOT_FOUND,
  60 };
  61
  62 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  63
  64 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  65 {
  66         symbol_type = toupper(symbol_type);
  67
  68         switch (map_type) {
  69         case MAP__FUNCTION:
  70                 return symbol_type == 'T' || symbol_type == 'W';
  71         case MAP__VARIABLE:
  72                 return symbol_type == 'D';
  73         default:
  74                 return false;
  75         }
  76 }
  77
  78 static int prefix_underscores_count(const char *str)
  79 {
  80         const char *tail = str;
  81
  82         while (*tail == '_')
  83                 tail++;
  84
  85         return tail - str;
  86 }
  87
  88 int __weak arch__choose_best_symbol(struct symbol *syma,
  89                                     struct symbol *symb __maybe_unused)
  90 {
  91         /* Avoid "SyS" kernel syscall aliases */
  92         if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
  93                 return SYMBOL_B;
  94         if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
  95                 return SYMBOL_B;
  96
  97         return SYMBOL_A;
  98 }
  99
 100 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 101 {
 102         s64 a;
 103         s64 b;
 104         size_t na, nb;
 105
 106         /* Prefer a symbol with non zero length */
 107         a = syma->end - syma->start;
 108         b = symb->end - symb->start;
 109         if ((b == 0) && (a > 0))
 110                 return SYMBOL_A;
 111         else if ((a == 0) && (b > 0))
 112                 return SYMBOL_B;
 113
 114         /* Prefer a non weak symbol over a weak one */
 115         a = syma->binding == STB_WEAK;
 116         b = symb->binding == STB_WEAK;
 117         if (b && !a)
 118                 return SYMBOL_A;
 119         if (a && !b)
 120                 return SYMBOL_B;
 121
 122         /* Prefer a global symbol over a non global one */
 123         a = syma->binding == STB_GLOBAL;
 124         b = symb->binding == STB_GLOBAL;
 125         if (a && !b)
 126                 return SYMBOL_A;
 127         if (b && !a)
 128                 return SYMBOL_B;
 129
 130         /* Prefer a symbol with less underscores */
 131         a = prefix_underscores_count(syma->name);
 132         b = prefix_underscores_count(symb->name);
 133         if (b > a)
 134                 return SYMBOL_A;
 135         else if (a > b)
 136                 return SYMBOL_B;
 137
 138         /* Choose the symbol with the longest name */
 139         na = strlen(syma->name);
 140         nb = strlen(symb->name);
 141         if (na > nb)
 142                 return SYMBOL_A;
 143         else if (na < nb)
 144                 return SYMBOL_B;
 145
 146         return arch__choose_best_symbol(syma, symb);
 147 }
 148
 149 void symbols__fixup_duplicate(struct rb_root *symbols)
 150 {
 151         struct rb_node *nd;
 152         struct symbol *curr, *next;
 153
 154         nd = rb_first(symbols);
 155
 156         while (nd) {
 157                 curr = rb_entry(nd, struct symbol, rb_node);
 158 again:
 159                 nd = rb_next(&curr->rb_node);
 160                 next = rb_entry(nd, struct symbol, rb_node);
 161
 162                 if (!nd)
 163                         break;
 164
 165                 if (curr->start != next->start)
 166                         continue;
 167
 168                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 169                         rb_erase(&next->rb_node, symbols);
 170                         symbol__delete(next);
 171                         goto again;
 172                 } else {
 173                         nd = rb_next(&curr->rb_node);
 174                         rb_erase(&curr->rb_node, symbols);
 175                         symbol__delete(curr);
 176                 }
 177         }
 178 }
 179
 180 void symbols__fixup_end(struct rb_root *symbols)
 181 {
 182         struct rb_node *nd, *prevnd = rb_first(symbols);
 183         struct symbol *curr, *prev;
 184
 185         if (prevnd == NULL)
 186                 return;
 187
 188         curr = rb_entry(prevnd, struct symbol, rb_node);
 189
 190         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 191                 prev = curr;
 192                 curr = rb_entry(nd, struct symbol, rb_node);
 193
 194                 if (prev->end == prev->start && prev->end != curr->start)
 195                         prev->end = curr->start;
 196         }
 197
 198         /* Last entry */
 199         if (curr->end == curr->start)
 200                 curr->end = roundup(curr->start, 4096);
 201 }
 202
 203 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 204 {
 205         struct maps *maps = &mg->maps[type];
 206         struct map *next, *curr;
 207
 208         pthread_rwlock_wrlock(&maps->lock);
 209
 210         curr = maps__first(maps);
 211         if (curr == NULL)
 212                 goto out_unlock;
 213
 214         for (next = map__next(curr); next; next = map__next(curr)) {
 215                 curr->end = next->start;
 216                 curr = next;
 217         }
 218
 219         /*
 220          * We still haven't the actual symbols, so guess the
 221          * last map final address.
 222          */
 223         curr->end = ~0ULL;
 224
 225 out_unlock:
 226         pthread_rwlock_unlock(&maps->lock);
 227 }
 228
 229 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 230 {
 231         size_t namelen = strlen(name) + 1;
 232         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 233                                         sizeof(*sym) + namelen));
 234         if (sym == NULL)
 235                 return NULL;
 236
 237         if (symbol_conf.priv_size)
 238                 sym = ((void *)sym) + symbol_conf.priv_size;
 239
 240         sym->start   = start;
 241         sym->end     = len ? start + len : start;
 242         sym->binding = binding;
 243         sym->namelen = namelen - 1;
 244
 245         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 246                   __func__, name, start, sym->end);
 247         memcpy(sym->name, name, namelen);
 248
 249         return sym;
 250 }
 251
 252 void symbol__delete(struct symbol *sym)
 253 {
 254         free(((void *)sym) - symbol_conf.priv_size);
 255 }
 256
 257 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 258 {
 259         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 260                        sym->start, sym->end,
 261                        sym->binding == STB_GLOBAL ? 'g' :
 262                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 263                        sym->name);
 264 }
 265
 266 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 267                                     const struct addr_location *al, FILE *fp)
 268 {
 269         unsigned long offset;
 270         size_t length;
 271
 272         if (sym && sym->name) {
 273                 length = fprintf(fp, "%s", sym->name);
 274                 if (al) {
 275                         if (al->addr < sym->end)
 276                                 offset = al->addr - sym->start;
 277                         else
 278                                 offset = al->addr - al->map->start - sym->start;
 279                         length += fprintf(fp, "+0x%lx", offset);
 280                 }
 281                 return length;
 282         } else
 283                 return fprintf(fp, "[unknown]");
 284 }
 285
 286 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 287 {
 288         return symbol__fprintf_symname_offs(sym, NULL, fp);
 289 }
 290
 291 void symbols__delete(struct rb_root *symbols)
 292 {
 293         struct symbol *pos;
 294         struct rb_node *next = rb_first(symbols);
 295
 296         while (next) {
 297                 pos = rb_entry(next, struct symbol, rb_node);
 298                 next = rb_next(&pos->rb_node);
 299                 rb_erase(&pos->rb_node, symbols);
 300                 symbol__delete(pos);
 301         }
 302 }
 303
 304 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 305 {
 306         struct rb_node **p = &symbols->rb_node;
 307         struct rb_node *parent = NULL;
 308         const u64 ip = sym->start;
 309         struct symbol *s;
 310
 311         while (*p != NULL) {
 312                 parent = *p;
 313                 s = rb_entry(parent, struct symbol, rb_node);
 314                 if (ip < s->start)
 315                         p = &(*p)->rb_left;
 316                 else
 317                         p = &(*p)->rb_right;
 318         }
 319         rb_link_node(&sym->rb_node, parent, p);
 320         rb_insert_color(&sym->rb_node, symbols);
 321 }
 322
 323 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 324 {
 325         struct rb_node *n;
 326
 327         if (symbols == NULL)
 328                 return NULL;
 329
 330         n = symbols->rb_node;
 331
 332         while (n) {
 333                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 334
 335                 if (ip < s->start)
 336                         n = n->rb_left;
 337                 else if (ip >= s->end)
 338                         n = n->rb_right;
 339                 else
 340                         return s;
 341         }
 342
 343         return NULL;
 344 }
 345
 346 static struct symbol *symbols__first(struct rb_root *symbols)
 347 {
 348         struct rb_node *n = rb_first(symbols);
 349
 350         if (n)
 351                 return rb_entry(n, struct symbol, rb_node);
 352
 353         return NULL;
 354 }
 355
 356 static struct symbol *symbols__next(struct symbol *sym)
 357 {
 358         struct rb_node *n = rb_next(&sym->rb_node);
 359
 360         if (n)
 361                 return rb_entry(n, struct symbol, rb_node);
 362
 363         return NULL;
 364 }
 365
 366 struct symbol_name_rb_node {
 367         struct rb_node  rb_node;
 368         struct symbol   sym;
 369 };
 370
 371 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 372 {
 373         struct rb_node **p = &symbols->rb_node;
 374         struct rb_node *parent = NULL;
 375         struct symbol_name_rb_node *symn, *s;
 376
 377         symn = container_of(sym, struct symbol_name_rb_node, sym);
 378
 379         while (*p != NULL) {
 380                 parent = *p;
 381                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 382                 if (strcmp(sym->name, s->sym.name) < 0)
 383                         p = &(*p)->rb_left;
 384                 else
 385                         p = &(*p)->rb_right;
 386         }
 387         rb_link_node(&symn->rb_node, parent, p);
 388         rb_insert_color(&symn->rb_node, symbols);
 389 }
 390
 391 static void symbols__sort_by_name(struct rb_root *symbols,
 392                                   struct rb_root *source)
 393 {
 394         struct rb_node *nd;
 395
 396         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 397                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 398                 symbols__insert_by_name(symbols, pos);
 399         }
 400 }
 401
 402 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 403                                             const char *name)
 404 {
 405         struct rb_node *n;
 406         struct symbol_name_rb_node *s = NULL;
 407
 408         if (symbols == NULL)
 409                 return NULL;
 410
 411         n = symbols->rb_node;
 412
 413         while (n) {
 414                 int cmp;
 415
 416                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 417                 cmp = arch__compare_symbol_names(name, s->sym.name);
 418
 419                 if (cmp < 0)
 420                         n = n->rb_left;
 421                 else if (cmp > 0)
 422                         n = n->rb_right;
 423                 else
 424                         break;
 425         }
 426
 427         if (n == NULL)
 428                 return NULL;
 429
 430         /* return first symbol that has same name (if any) */
 431         for (n = rb_prev(n); n; n = rb_prev(n)) {
 432                 struct symbol_name_rb_node *tmp;
 433
 434                 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
 435                 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
 436                         break;
 437
 438                 s = tmp;
 439         }
 440
 441         return &s->sym;
 442 }
 443
 444 struct symbol *dso__find_symbol(struct dso *dso,
 445                                 enum map_type type, u64 addr)
 446 {
 447         return symbols__find(&dso->symbols[type], addr);
 448 }
 449
 450 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
 451 {
 452         return symbols__first(&dso->symbols[type]);
 453 }
 454
 455 struct symbol *dso__next_symbol(struct symbol *sym)
 456 {
 457         return symbols__next(sym);
 458 }
 459
 460 struct symbol *symbol__next_by_name(struct symbol *sym)
 461 {
 462         struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
 463         struct rb_node *n = rb_next(&s->rb_node);
 464
 465         return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
 466 }
 467
 468  /*
 469   * Teturns first symbol that matched with @name.
 470   */
 471 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 472                                         const char *name)
 473 {
 474         return symbols__find_by_name(&dso->symbol_names[type], name);
 475 }
 476
 477 void dso__sort_by_name(struct dso *dso, enum map_type type)
 478 {
 479         dso__set_sorted_by_name(dso, type);
 480         return symbols__sort_by_name(&dso->symbol_names[type],
 481                                      &dso->symbols[type]);
 482 }
 483
 484 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 485                                     enum map_type type, FILE *fp)
 486 {
 487         size_t ret = 0;
 488         struct rb_node *nd;
 489         struct symbol_name_rb_node *pos;
 490
 491         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 492                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 493                 fprintf(fp, "%s\n", pos->sym.name);
 494         }
 495
 496         return ret;
 497 }
 498
 499 int modules__parse(const char *filename, void *arg,
 500                    int (*process_module)(void *arg, const char *name,
 501                                          u64 start))
 502 {
 503         char *line = NULL;
 504         size_t n;
 505         FILE *file;
 506         int err = 0;
 507
 508         file = fopen(filename, "r");
 509         if (file == NULL)
 510                 return -1;
 511
 512         while (1) {
 513                 char name[PATH_MAX];
 514                 u64 start;
 515                 char *sep;
 516                 ssize_t line_len;
 517
 518                 line_len = getline(&line, &n, file);
 519                 if (line_len < 0) {
 520                         if (feof(file))
 521                                 break;
 522                         err = -1;
 523                         goto out;
 524                 }
 525
 526                 if (!line) {
 527                         err = -1;
 528                         goto out;
 529                 }
 530
 531                 line[--line_len] = '\0'; /* \n */
 532
 533                 sep = strrchr(line, 'x');
 534                 if (sep == NULL)
 535                         continue;
 536
 537                 hex2u64(sep + 1, &start);
 538
 539                 sep = strchr(line, ' ');
 540                 if (sep == NULL)
 541                         continue;
 542
 543                 *sep = '\0';
 544
 545                 scnprintf(name, sizeof(name), "[%s]", line);
 546
 547                 err = process_module(arg, name, start);
 548                 if (err)
 549                         break;
 550         }
 551 out:
 552         free(line);
 553         fclose(file);
 554         return err;
 555 }
 556
 557 struct process_kallsyms_args {
 558         struct map *map;
 559         struct dso *dso;
 560 };
 561
 562 /*
 563  * These are symbols in the kernel image, so make sure that
 564  * sym is from a kernel DSO.
 565  */
 566 bool symbol__is_idle(struct symbol *sym)
 567 {
 568         const char * const idle_symbols[] = {
 569                 "cpu_idle",
 570                 "cpu_startup_entry",
 571                 "intel_idle",
 572                 "default_idle",
 573                 "native_safe_halt",
 574                 "enter_idle",
 575                 "exit_idle",
 576                 "mwait_idle",
 577                 "mwait_idle_with_hints",
 578                 "poll_idle",
 579                 "ppc64_runlatch_off",
 580                 "pseries_dedicated_idle_sleep",
 581                 NULL
 582         };
 583
 584         int i;
 585
 586         if (!sym)
 587                 return false;
 588
 589         for (i = 0; idle_symbols[i]; i++) {
 590                 if (!strcmp(idle_symbols[i], sym->name))
 591                         return true;
 592         }
 593
 594         return false;
 595 }
 596
 597 static int map__process_kallsym_symbol(void *arg, const char *name,
 598                                        char type, u64 start)
 599 {
 600         struct symbol *sym;
 601         struct process_kallsyms_args *a = arg;
 602         struct rb_root *root = &a->dso->symbols[a->map->type];
 603
 604         if (!symbol_type__is_a(type, a->map->type))
 605                 return 0;
 606
 607         /*
 608          * module symbols are not sorted so we add all
 609          * symbols, setting length to 0, and rely on
 610          * symbols__fixup_end() to fix it up.
 611          */
 612         sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
 613         if (sym == NULL)
 614                 return -ENOMEM;
 615         /*
 616          * We will pass the symbols to the filter later, in
 617          * map__split_kallsyms, when we have split the maps per module
 618          */
 619         symbols__insert(root, sym);
 620
 621         return 0;
 622 }
 623
 624 /*
 625  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 626  * so that we can in the next step set the symbol ->end address and then
 627  * call kernel_maps__split_kallsyms.
 628  */
 629 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 630                                   struct map *map)
 631 {
 632         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 633         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 634 }
 635
 636 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
 637                                          symbol_filter_t filter)
 638 {
 639         struct map_groups *kmaps = map__kmaps(map);
 640         struct map *curr_map;
 641         struct symbol *pos;
 642         int count = 0, moved = 0;
 643         struct rb_root *root = &dso->symbols[map->type];
 644         struct rb_node *next = rb_first(root);
 645
 646         if (!kmaps)
 647                 return -1;
 648
 649         while (next) {
 650                 char *module;
 651
 652                 pos = rb_entry(next, struct symbol, rb_node);
 653                 next = rb_next(&pos->rb_node);
 654
 655                 module = strchr(pos->name, '\t');
 656                 if (module)
 657                         *module = '\0';
 658
 659                 curr_map = map_groups__find(kmaps, map->type, pos->start);
 660
 661                 if (!curr_map || (filter && filter(curr_map, pos))) {
 662                         rb_erase_init(&pos->rb_node, root);
 663                         symbol__delete(pos);
 664                 } else {
 665                         pos->start -= curr_map->start - curr_map->pgoff;
 666                         if (pos->end)
 667                                 pos->end -= curr_map->start - curr_map->pgoff;
 668                         if (curr_map != map) {
 669                                 rb_erase_init(&pos->rb_node, root);
 670                                 symbols__insert(
 671                                         &curr_map->dso->symbols[curr_map->type],
 672                                         pos);
 673                                 ++moved;
 674                         } else {
 675                                 ++count;
 676                         }
 677                 }
 678         }
 679
 680         /* Symbols have been adjusted */
 681         dso->adjust_symbols = 1;
 682
 683         return count + moved;
 684 }
 685
 686 /*
 687  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 688  * kernel range is broken in several maps, named [kernel].N, as we don't have
 689  * the original ELF section names vmlinux have.
 690  */
 691 static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
 692                                symbol_filter_t filter)
 693 {
 694         struct map_groups *kmaps = map__kmaps(map);
 695         struct machine *machine;
 696         struct map *curr_map = map;
 697         struct symbol *pos;
 698         int count = 0, moved = 0;
 699         struct rb_root *root = &dso->symbols[map->type];
 700         struct rb_node *next = rb_first(root);
 701         int kernel_range = 0;
 702
 703         if (!kmaps)
 704                 return -1;
 705
 706         machine = kmaps->machine;
 707
 708         while (next) {
 709                 char *module;
 710
 711                 pos = rb_entry(next, struct symbol, rb_node);
 712                 next = rb_next(&pos->rb_node);
 713
 714                 module = strchr(pos->name, '\t');
 715                 if (module) {
 716                         if (!symbol_conf.use_modules)
 717                                 goto discard_symbol;
 718
 719                         *module++ = '\0';
 720
 721                         if (strcmp(curr_map->dso->short_name, module)) {
 722                                 if (curr_map != map &&
 723                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 724                                     machine__is_default_guest(machine)) {
 725                                         /*
 726                                          * We assume all symbols of a module are
 727                                          * continuous in * kallsyms, so curr_map
 728                                          * points to a module and all its
 729                                          * symbols are in its kmap. Mark it as
 730                                          * loaded.
 731                                          */
 732                                         dso__set_loaded(curr_map->dso,
 733                                                         curr_map->type);
 734                                 }
 735
 736                                 curr_map = map_groups__find_by_name(kmaps,
 737                                                         map->type, module);
 738                                 if (curr_map == NULL) {
 739                                         pr_debug("%s/proc/{kallsyms,modules} "
 740                                                  "inconsistency while looking "
 741                                                  "for \"%s\" module!\n",
 742                                                  machine->root_dir, module);
 743                                         curr_map = map;
 744                                         goto discard_symbol;
 745                                 }
 746
 747                                 if (curr_map->dso->loaded &&
 748                                     !machine__is_default_guest(machine))
 749                                         goto discard_symbol;
 750                         }
 751                         /*
 752                          * So that we look just like we get from .ko files,
 753                          * i.e. not prelinked, relative to map->start.
 754                          */
 755                         pos->start = curr_map->map_ip(curr_map, pos->start);
 756                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 757                 } else if (curr_map != map) {
 758                         char dso_name[PATH_MAX];
 759                         struct dso *ndso;
 760
 761                         if (delta) {
 762                                 /* Kernel was relocated at boot time */
 763                                 pos->start -= delta;
 764                                 pos->end -= delta;
 765                         }
 766
 767                         if (count == 0) {
 768                                 curr_map = map;
 769                                 goto filter_symbol;
 770                         }
 771
 772                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 773                                 snprintf(dso_name, sizeof(dso_name),
 774                                         "[guest.kernel].%d",
 775                                         kernel_range++);
 776                         else
 777                                 snprintf(dso_name, sizeof(dso_name),
 778                                         "[kernel].%d",
 779                                         kernel_range++);
 780
 781                         ndso = dso__new(dso_name);
 782                         if (ndso == NULL)
 783                                 return -1;
 784
 785                         ndso->kernel = dso->kernel;
 786
 787                         curr_map = map__new2(pos->start, ndso, map->type);
 788                         if (curr_map == NULL) {
 789                                 dso__put(ndso);
 790                                 return -1;
 791                         }
 792
 793                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 794                         map_groups__insert(kmaps, curr_map);
 795                         ++kernel_range;
 796                 } else if (delta) {
 797                         /* Kernel was relocated at boot time */
 798                         pos->start -= delta;
 799                         pos->end -= delta;
 800                 }
 801 filter_symbol:
 802                 if (filter && filter(curr_map, pos)) {
 803 discard_symbol:         rb_erase(&pos->rb_node, root);
 804                         symbol__delete(pos);
 805                 } else {
 806                         if (curr_map != map) {
 807                                 rb_erase(&pos->rb_node, root);
 808                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 809                                 ++moved;
 810                         } else
 811                                 ++count;
 812                 }
 813         }
 814
 815         if (curr_map != map &&
 816             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 817             machine__is_default_guest(kmaps->machine)) {
 818                 dso__set_loaded(curr_map->dso, curr_map->type);
 819         }
 820
 821         return count + moved;
 822 }
 823
 824 bool symbol__restricted_filename(const char *filename,
 825                                  const char *restricted_filename)
 826 {
 827         bool restricted = false;
 828
 829         if (symbol_conf.kptr_restrict) {
 830                 char *r = realpath(filename, NULL);
 831
 832                 if (r != NULL) {
 833                         restricted = strcmp(r, restricted_filename) == 0;
 834                         free(r);
 835                         return restricted;
 836                 }
 837         }
 838
 839         return restricted;
 840 }
 841
 842 struct module_info {
 843         struct rb_node rb_node;
 844         char *name;
 845         u64 start;
 846 };
 847
 848 static void add_module(struct module_info *mi, struct rb_root *modules)
 849 {
 850         struct rb_node **p = &modules->rb_node;
 851         struct rb_node *parent = NULL;
 852         struct module_info *m;
 853
 854         while (*p != NULL) {
 855                 parent = *p;
 856                 m = rb_entry(parent, struct module_info, rb_node);
 857                 if (strcmp(mi->name, m->name) < 0)
 858                         p = &(*p)->rb_left;
 859                 else
 860                         p = &(*p)->rb_right;
 861         }
 862         rb_link_node(&mi->rb_node, parent, p);
 863         rb_insert_color(&mi->rb_node, modules);
 864 }
 865
 866 static void delete_modules(struct rb_root *modules)
 867 {
 868         struct module_info *mi;
 869         struct rb_node *next = rb_first(modules);
 870
 871         while (next) {
 872                 mi = rb_entry(next, struct module_info, rb_node);
 873                 next = rb_next(&mi->rb_node);
 874                 rb_erase(&mi->rb_node, modules);
 875                 zfree(&mi->name);
 876                 free(mi);
 877         }
 878 }
 879
 880 static struct module_info *find_module(const char *name,
 881                                        struct rb_root *modules)
 882 {
 883         struct rb_node *n = modules->rb_node;
 884
 885         while (n) {
 886                 struct module_info *m;
 887                 int cmp;
 888
 889                 m = rb_entry(n, struct module_info, rb_node);
 890                 cmp = strcmp(name, m->name);
 891                 if (cmp < 0)
 892                         n = n->rb_left;
 893                 else if (cmp > 0)
 894                         n = n->rb_right;
 895                 else
 896                         return m;
 897         }
 898
 899         return NULL;
 900 }
 901
 902 static int __read_proc_modules(void *arg, const char *name, u64 start)
 903 {
 904         struct rb_root *modules = arg;
 905         struct module_info *mi;
 906
 907         mi = zalloc(sizeof(struct module_info));
 908         if (!mi)
 909                 return -ENOMEM;
 910
 911         mi->name = strdup(name);
 912         mi->start = start;
 913
 914         if (!mi->name) {
 915                 free(mi);
 916                 return -ENOMEM;
 917         }
 918
 919         add_module(mi, modules);
 920
 921         return 0;
 922 }
 923
 924 static int read_proc_modules(const char *filename, struct rb_root *modules)
 925 {
 926         if (symbol__restricted_filename(filename, "/proc/modules"))
 927                 return -1;
 928
 929         if (modules__parse(filename, modules, __read_proc_modules)) {
 930                 delete_modules(modules);
 931                 return -1;
 932         }
 933
 934         return 0;
 935 }
 936
 937 int compare_proc_modules(const char *from, const char *to)
 938 {
 939         struct rb_root from_modules = RB_ROOT;
 940         struct rb_root to_modules = RB_ROOT;
 941         struct rb_node *from_node, *to_node;
 942         struct module_info *from_m, *to_m;
 943         int ret = -1;
 944
 945         if (read_proc_modules(from, &from_modules))
 946                 return -1;
 947
 948         if (read_proc_modules(to, &to_modules))
 949                 goto out_delete_from;
 950
 951         from_node = rb_first(&from_modules);
 952         to_node = rb_first(&to_modules);
 953         while (from_node) {
 954                 if (!to_node)
 955                         break;
 956
 957                 from_m = rb_entry(from_node, struct module_info, rb_node);
 958                 to_m = rb_entry(to_node, struct module_info, rb_node);
 959
 960                 if (from_m->start != to_m->start ||
 961                     strcmp(from_m->name, to_m->name))
 962                         break;
 963
 964                 from_node = rb_next(from_node);
 965                 to_node = rb_next(to_node);
 966         }
 967
 968         if (!from_node && !to_node)
 969                 ret = 0;
 970
 971         delete_modules(&to_modules);
 972 out_delete_from:
 973         delete_modules(&from_modules);
 974
 975         return ret;
 976 }
 977
 978 static int do_validate_kcore_modules(const char *filename, struct map *map,
 979                                   struct map_groups *kmaps)
 980 {
 981         struct rb_root modules = RB_ROOT;
 982         struct map *old_map;
 983         int err;
 984
 985         err = read_proc_modules(filename, &modules);
 986         if (err)
 987                 return err;
 988
 989         old_map = map_groups__first(kmaps, map->type);
 990         while (old_map) {
 991                 struct map *next = map_groups__next(old_map);
 992                 struct module_info *mi;
 993
 994                 if (old_map == map || old_map->start == map->start) {
 995                         /* The kernel map */
 996                         old_map = next;
 997                         continue;
 998                 }
 999
1000                 /* Module must be in memory at the same address */
1001                 mi = find_module(old_map->dso->short_name, &modules);
1002                 if (!mi || mi->start != old_map->start) {
1003                         err = -EINVAL;
1004                         goto out;
1005                 }
1006
1007                 old_map = next;
1008         }
1009 out:
1010         delete_modules(&modules);
1011         return err;
1012 }
1013
1014 /*
1015  * If kallsyms is referenced by name then we look for filename in the same
1016  * directory.
1017  */
1018 static bool filename_from_kallsyms_filename(char *filename,
1019                                             const char *base_name,
1020                                             const char *kallsyms_filename)
1021 {
1022         char *name;
1023
1024         strcpy(filename, kallsyms_filename);
1025         name = strrchr(filename, '/');
1026         if (!name)
1027                 return false;
1028
1029         name += 1;
1030
1031         if (!strcmp(name, "kallsyms")) {
1032                 strcpy(name, base_name);
1033                 return true;
1034         }
1035
1036         return false;
1037 }
1038
1039 static int validate_kcore_modules(const char *kallsyms_filename,
1040                                   struct map *map)
1041 {
1042         struct map_groups *kmaps = map__kmaps(map);
1043         char modules_filename[PATH_MAX];
1044
1045         if (!kmaps)
1046                 return -EINVAL;
1047
1048         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1049                                              kallsyms_filename))
1050                 return -EINVAL;
1051
1052         if (do_validate_kcore_modules(modules_filename, map, kmaps))
1053                 return -EINVAL;
1054
1055         return 0;
1056 }
1057
1058 static int validate_kcore_addresses(const char *kallsyms_filename,
1059                                     struct map *map)
1060 {
1061         struct kmap *kmap = map__kmap(map);
1062
1063         if (!kmap)
1064                 return -EINVAL;
1065
1066         if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1067                 u64 start;
1068
1069                 start = kallsyms__get_function_start(kallsyms_filename,
1070                                                      kmap->ref_reloc_sym->name);
1071                 if (start != kmap->ref_reloc_sym->addr)
1072                         return -EINVAL;
1073         }
1074
1075         return validate_kcore_modules(kallsyms_filename, map);
1076 }
1077
1078 struct kcore_mapfn_data {
1079         struct dso *dso;
1080         enum map_type type;
1081         struct list_head maps;
1082 };
1083
1084 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1085 {
1086         struct kcore_mapfn_data *md = data;
1087         struct map *map;
1088
1089         map = map__new2(start, md->dso, md->type);
1090         if (map == NULL)
1091                 return -ENOMEM;
1092
1093         map->end = map->start + len;
1094         map->pgoff = pgoff;
1095
1096         list_add(&map->node, &md->maps);
1097
1098         return 0;
1099 }
1100
1101 static int dso__load_kcore(struct dso *dso, struct map *map,
1102                            const char *kallsyms_filename)
1103 {
1104         struct map_groups *kmaps = map__kmaps(map);
1105         struct machine *machine;
1106         struct kcore_mapfn_data md;
1107         struct map *old_map, *new_map, *replacement_map = NULL;
1108         bool is_64_bit;
1109         int err, fd;
1110         char kcore_filename[PATH_MAX];
1111         struct symbol *sym;
1112
1113         if (!kmaps)
1114                 return -EINVAL;
1115
1116         machine = kmaps->machine;
1117
1118         /* This function requires that the map is the kernel map */
1119         if (map != machine->vmlinux_maps[map->type])
1120                 return -EINVAL;
1121
1122         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1123                                              kallsyms_filename))
1124                 return -EINVAL;
1125
1126         /* Modules and kernel must be present at their original addresses */
1127         if (validate_kcore_addresses(kallsyms_filename, map))
1128                 return -EINVAL;
1129
1130         md.dso = dso;
1131         md.type = map->type;
1132         INIT_LIST_HEAD(&md.maps);
1133
1134         fd = open(kcore_filename, O_RDONLY);
1135         if (fd < 0) {
1136                 pr_err("%s requires CAP_SYS_RAWIO capability to access.\n",
1137                         kcore_filename);
1138                 return -EINVAL;
1139         }
1140
1141         /* Read new maps into temporary lists */
1142         err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1143                               &is_64_bit);
1144         if (err)
1145                 goto out_err;
1146         dso->is_64_bit = is_64_bit;
1147
1148         if (list_empty(&md.maps)) {
1149                 err = -EINVAL;
1150                 goto out_err;
1151         }
1152
1153         /* Remove old maps */
1154         old_map = map_groups__first(kmaps, map->type);
1155         while (old_map) {
1156                 struct map *next = map_groups__next(old_map);
1157
1158                 if (old_map != map)
1159                         map_groups__remove(kmaps, old_map);
1160                 old_map = next;
1161         }
1162
1163         /* Find the kernel map using the first symbol */
1164         sym = dso__first_symbol(dso, map->type);
1165         list_for_each_entry(new_map, &md.maps, node) {
1166                 if (sym && sym->start >= new_map->start &&
1167                     sym->start < new_map->end) {
1168                         replacement_map = new_map;
1169                         break;
1170                 }
1171         }
1172
1173         if (!replacement_map)
1174                 replacement_map = list_entry(md.maps.next, struct map, node);
1175
1176         /* Add new maps */
1177         while (!list_empty(&md.maps)) {
1178                 new_map = list_entry(md.maps.next, struct map, node);
1179                 list_del_init(&new_map->node);
1180                 if (new_map == replacement_map) {
1181                         map->start      = new_map->start;
1182                         map->end        = new_map->end;
1183                         map->pgoff      = new_map->pgoff;
1184                         map->map_ip     = new_map->map_ip;
1185                         map->unmap_ip   = new_map->unmap_ip;
1186                         /* Ensure maps are correctly ordered */
1187                         map__get(map);
1188                         map_groups__remove(kmaps, map);
1189                         map_groups__insert(kmaps, map);
1190                         map__put(map);
1191                 } else {
1192                         map_groups__insert(kmaps, new_map);
1193                 }
1194
1195                 map__put(new_map);
1196         }
1197
1198         /*
1199          * Set the data type and long name so that kcore can be read via
1200          * dso__data_read_addr().
1201          */
1202         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1203                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1204         else
1205                 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1206         dso__set_long_name(dso, strdup(kcore_filename), true);
1207
1208         close(fd);
1209
1210         if (map->type == MAP__FUNCTION)
1211                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1212         else
1213                 pr_debug("Using %s for kernel data\n", kcore_filename);
1214
1215         return 0;
1216
1217 out_err:
1218         while (!list_empty(&md.maps)) {
1219                 map = list_entry(md.maps.next, struct map, node);
1220                 list_del_init(&map->node);
1221                 map__put(map);
1222         }
1223         close(fd);
1224         return -EINVAL;
1225 }
1226
1227 /*
1228  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1229  * delta based on the relocation reference symbol.
1230  */
1231 static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
1232 {
1233         struct kmap *kmap = map__kmap(map);
1234         u64 addr;
1235
1236         if (!kmap)
1237                 return -1;
1238
1239         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1240                 return 0;
1241
1242         addr = kallsyms__get_function_start(filename,
1243                                             kmap->ref_reloc_sym->name);
1244         if (!addr)
1245                 return -1;
1246
1247         *delta = addr - kmap->ref_reloc_sym->addr;
1248         return 0;
1249 }
1250
1251 int dso__load_kallsyms(struct dso *dso, const char *filename,
1252                        struct map *map, symbol_filter_t filter)
1253 {
1254         u64 delta = 0;
1255
1256         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1257                 return -1;
1258
1259         if (dso__load_all_kallsyms(dso, filename, map) < 0)
1260                 return -1;
1261
1262         if (kallsyms__delta(map, filename, &delta))
1263                 return -1;
1264
1265         symbols__fixup_duplicate(&dso->symbols[map->type]);
1266         symbols__fixup_end(&dso->symbols[map->type]);
1267
1268         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1269                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1270         else
1271                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1272
1273         if (!dso__load_kcore(dso, map, filename))
1274                 return dso__split_kallsyms_for_kcore(dso, map, filter);
1275         else
1276                 return dso__split_kallsyms(dso, map, delta, filter);
1277 }
1278
1279 static int dso__load_perf_map(struct dso *dso, struct map *map,
1280                               symbol_filter_t filter)
1281 {
1282         char *line = NULL;
1283         size_t n;
1284         FILE *file;
1285         int nr_syms = 0;
1286
1287         file = fopen(dso->long_name, "r");
1288         if (file == NULL)
1289                 goto out_failure;
1290
1291         while (!feof(file)) {
1292                 u64 start, size;
1293                 struct symbol *sym;
1294                 int line_len, len;
1295
1296                 line_len = getline(&line, &n, file);
1297                 if (line_len < 0)
1298                         break;
1299
1300                 if (!line)
1301                         goto out_failure;
1302
1303                 line[--line_len] = '\0'; /* \n */
1304
1305                 len = hex2u64(line, &start);
1306
1307                 len++;
1308                 if (len + 2 >= line_len)
1309                         continue;
1310
1311                 len += hex2u64(line + len, &size);
1312
1313                 len++;
1314                 if (len + 2 >= line_len)
1315                         continue;
1316
1317                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
1318
1319                 if (sym == NULL)
1320                         goto out_delete_line;
1321
1322                 if (filter && filter(map, sym))
1323                         symbol__delete(sym);
1324                 else {
1325                         symbols__insert(&dso->symbols[map->type], sym);
1326                         nr_syms++;
1327                 }
1328         }
1329
1330         free(line);
1331         fclose(file);
1332
1333         return nr_syms;
1334
1335 out_delete_line:
1336         free(line);
1337 out_failure:
1338         return -1;
1339 }
1340
1341 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1342                                            enum dso_binary_type type)
1343 {
1344         switch (type) {
1345         case DSO_BINARY_TYPE__JAVA_JIT:
1346         case DSO_BINARY_TYPE__DEBUGLINK:
1347         case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1348         case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1349         case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1350         case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1351         case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1352                 return !kmod && dso->kernel == DSO_TYPE_USER;
1353
1354         case DSO_BINARY_TYPE__KALLSYMS:
1355         case DSO_BINARY_TYPE__VMLINUX:
1356         case DSO_BINARY_TYPE__KCORE:
1357                 return dso->kernel == DSO_TYPE_KERNEL;
1358
1359         case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1360         case DSO_BINARY_TYPE__GUEST_VMLINUX:
1361         case DSO_BINARY_TYPE__GUEST_KCORE:
1362                 return dso->kernel == DSO_TYPE_GUEST_KERNEL;
1363
1364         case DSO_BINARY_TYPE__GUEST_KMODULE:
1365         case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1366         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1367         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1368                 /*
1369                  * kernel modules know their symtab type - it's set when
1370                  * creating a module dso in machine__findnew_module_map().
1371                  */
1372                 return kmod && dso->symtab_type == type;
1373
1374         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1375                 return true;
1376
1377         case DSO_BINARY_TYPE__NOT_FOUND:
1378         default:
1379                 return false;
1380         }
1381 }
1382
1383 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1384 {
1385         char *name;
1386         int ret = -1;
1387         u_int i;
1388         struct machine *machine;
1389         char *root_dir = (char *) "";
1390         int ss_pos = 0;
1391         struct symsrc ss_[2];
1392         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1393         bool kmod;
1394
1395         pthread_mutex_lock(&dso->lock);
1396
1397         /* check again under the dso->lock */
1398         if (dso__loaded(dso, map->type)) {
1399                 ret = 1;
1400                 goto out;
1401         }
1402
1403         if (dso->kernel) {
1404                 if (dso->kernel == DSO_TYPE_KERNEL)
1405                         ret = dso__load_kernel_sym(dso, map, filter);
1406                 else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1407                         ret = dso__load_guest_kernel_sym(dso, map, filter);
1408
1409                 goto out;
1410         }
1411
1412         if (map->groups && map->groups->machine)
1413                 machine = map->groups->machine;
1414         else
1415                 machine = NULL;
1416
1417         dso->adjust_symbols = 0;
1418
1419         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1420                 struct stat st;
1421
1422                 if (lstat(dso->name, &st) < 0)
1423                         goto out;
1424
1425                 if (st.st_uid && (st.st_uid != geteuid())) {
1426                         pr_warning("File %s not owned by current user or root, "
1427                                 "ignoring it.\n", dso->name);
1428                         goto out;
1429                 }
1430
1431                 ret = dso__load_perf_map(dso, map, filter);
1432                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1433                                              DSO_BINARY_TYPE__NOT_FOUND;
1434                 goto out;
1435         }
1436
1437         if (machine)
1438                 root_dir = machine->root_dir;
1439
1440         name = malloc(PATH_MAX);
1441         if (!name)
1442                 goto out;
1443
1444         kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1445                 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1446                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1447                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1448
1449         /*
1450          * Iterate over candidate debug images.
1451          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1452          * and/or opd section) for processing.
1453          */
1454         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1455                 struct symsrc *ss = &ss_[ss_pos];
1456                 bool next_slot = false;
1457
1458                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1459
1460                 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1461                         continue;
1462
1463                 if (dso__read_binary_type_filename(dso, symtab_type,
1464                                                    root_dir, name, PATH_MAX))
1465                         continue;
1466
1467                 /* Name is now the name of the next image to try */
1468                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
1469                         continue;
1470
1471                 if (!syms_ss && symsrc__has_symtab(ss)) {
1472                         syms_ss = ss;
1473                         next_slot = true;
1474                         if (!dso->symsrc_filename)
1475                                 dso->symsrc_filename = strdup(name);
1476                 }
1477
1478                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1479                         runtime_ss = ss;
1480                         next_slot = true;
1481                 }
1482
1483                 if (next_slot) {
1484                         ss_pos++;
1485
1486                         if (syms_ss && runtime_ss)
1487                                 break;
1488                 } else {
1489                         symsrc__destroy(ss);
1490                 }
1491
1492         }
1493
1494         if (!runtime_ss && !syms_ss)
1495                 goto out_free;
1496
1497         if (runtime_ss && !syms_ss) {
1498                 syms_ss = runtime_ss;
1499         }
1500
1501         /* We'll have to hope for the best */
1502         if (!runtime_ss && syms_ss)
1503                 runtime_ss = syms_ss;
1504
1505         if (syms_ss)
1506                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, kmod);
1507         else
1508                 ret = -1;
1509
1510         if (ret > 0) {
1511                 int nr_plt;
1512
1513                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1514                 if (nr_plt > 0)
1515                         ret += nr_plt;
1516         }
1517
1518         for (; ss_pos > 0; ss_pos--)
1519                 symsrc__destroy(&ss_[ss_pos - 1]);
1520 out_free:
1521         free(name);
1522         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1523                 ret = 0;
1524 out:
1525         dso__set_loaded(dso, map->type);
1526         pthread_mutex_unlock(&dso->lock);
1527
1528         return ret;
1529 }
1530
1531 struct map *map_groups__find_by_name(struct map_groups *mg,
1532                                      enum map_type type, const char *name)
1533 {
1534         struct maps *maps = &mg->maps[type];
1535         struct map *map;
1536
1537         pthread_rwlock_rdlock(&maps->lock);
1538
1539         for (map = maps__first(maps); map; map = map__next(map)) {
1540                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1541                         goto out_unlock;
1542         }
1543
1544         map = NULL;
1545
1546 out_unlock:
1547         pthread_rwlock_unlock(&maps->lock);
1548         return map;
1549 }
1550
1551 int dso__load_vmlinux(struct dso *dso, struct map *map,
1552                       const char *vmlinux, bool vmlinux_allocated,
1553                       symbol_filter_t filter)
1554 {
1555         int err = -1;
1556         struct symsrc ss;
1557         char symfs_vmlinux[PATH_MAX];
1558         enum dso_binary_type symtab_type;
1559
1560         if (vmlinux[0] == '/')
1561                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1562         else
1563                 symbol__join_symfs(symfs_vmlinux, vmlinux);
1564
1565         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1566                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1567         else
1568                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1569
1570         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1571                 return -1;
1572
1573         err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1574         symsrc__destroy(&ss);
1575
1576         if (err > 0) {
1577                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1578                         dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1579                 else
1580                         dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1581                 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1582                 dso__set_loaded(dso, map->type);
1583                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1584         }
1585
1586         return err;
1587 }
1588
1589 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1590                            symbol_filter_t filter)
1591 {
1592         int i, err = 0;
1593         char *filename = NULL;
1594
1595         if (!symbol_conf.ignore_vmlinux_buildid)
1596                 filename = dso__build_id_filename(dso, NULL, 0);
1597         if (filename != NULL) {
1598                 err = dso__load_vmlinux(dso, map, filename, true, filter);
1599                 if (err > 0)
1600                         goto out;
1601                 free(filename);
1602         }
1603
1604         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1605                  vmlinux_path__nr_entries + 1);
1606
1607         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1608                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
1609                 if (err > 0)
1610                         break;
1611         }
1612 out:
1613         return err;
1614 }
1615
1616 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1617 {
1618         char kallsyms_filename[PATH_MAX];
1619         struct dirent *dent;
1620         int ret = -1;
1621         DIR *d;
1622
1623         d = opendir(dir);
1624         if (!d)
1625                 return -1;
1626
1627         while (1) {
1628                 dent = readdir(d);
1629                 if (!dent)
1630                         break;
1631                 if (dent->d_type != DT_DIR)
1632                         continue;
1633                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1634                           "%s/%s/kallsyms", dir, dent->d_name);
1635                 if (!validate_kcore_addresses(kallsyms_filename, map)) {
1636                         strlcpy(dir, kallsyms_filename, dir_sz);
1637                         ret = 0;
1638                         break;
1639                 }
1640         }
1641
1642         closedir(d);
1643
1644         return ret;
1645 }
1646
1647 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1648 {
1649         u8 host_build_id[BUILD_ID_SIZE];
1650         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1651         bool is_host = false;
1652         char path[PATH_MAX];
1653
1654         if (!dso->has_build_id) {
1655                 /*
1656                  * Last resort, if we don't have a build-id and couldn't find
1657                  * any vmlinux file, try the running kernel kallsyms table.
1658                  */
1659                 goto proc_kallsyms;
1660         }
1661
1662         if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1663                                  sizeof(host_build_id)) == 0)
1664                 is_host = dso__build_id_equal(dso, host_build_id);
1665
1666         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1667
1668         scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
1669                   sbuild_id);
1670
1671         /* Use /proc/kallsyms if possible */
1672         if (is_host) {
1673                 DIR *d;
1674                 int fd;
1675
1676                 /* If no cached kcore go with /proc/kallsyms */
1677                 d = opendir(path);
1678                 if (!d)
1679                         goto proc_kallsyms;
1680                 closedir(d);
1681
1682                 /*
1683                  * Do not check the build-id cache, until we know we cannot use
1684                  * /proc/kcore.
1685                  */
1686                 fd = open("/proc/kcore", O_RDONLY);
1687                 if (fd != -1) {
1688                         close(fd);
1689                         /* If module maps match go with /proc/kallsyms */
1690                         if (!validate_kcore_addresses("/proc/kallsyms", map))
1691                                 goto proc_kallsyms;
1692                 }
1693
1694                 /* Find kallsyms in build-id cache with kcore */
1695                 if (!find_matching_kcore(map, path, sizeof(path)))
1696                         return strdup(path);
1697
1698                 goto proc_kallsyms;
1699         }
1700
1701         /* Find kallsyms in build-id cache with kcore */
1702         if (!find_matching_kcore(map, path, sizeof(path)))
1703                 return strdup(path);
1704
1705         scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
1706                   buildid_dir, sbuild_id);
1707
1708         if (access(path, F_OK)) {
1709                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1710                        sbuild_id);
1711                 return NULL;
1712         }
1713
1714         return strdup(path);
1715
1716 proc_kallsyms:
1717         return strdup("/proc/kallsyms");
1718 }
1719
1720 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1721                                 symbol_filter_t filter)
1722 {
1723         int err;
1724         const char *kallsyms_filename = NULL;
1725         char *kallsyms_allocated_filename = NULL;
1726         /*
1727          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1728          * it and only it, reporting errors to the user if it cannot be used.
1729          *
1730          * For instance, try to analyse an ARM perf.data file _without_ a
1731          * build-id, or if the user specifies the wrong path to the right
1732          * vmlinux file, obviously we can't fallback to another vmlinux (a
1733          * x86_86 one, on the machine where analysis is being performed, say),
1734          * or worse, /proc/kallsyms.
1735          *
1736          * If the specified file _has_ a build-id and there is a build-id
1737          * section in the perf.data file, we will still do the expected
1738          * validation in dso__load_vmlinux and will bail out if they don't
1739          * match.
1740          */
1741         if (symbol_conf.kallsyms_name != NULL) {
1742                 kallsyms_filename = symbol_conf.kallsyms_name;
1743                 goto do_kallsyms;
1744         }
1745
1746         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1747                 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
1748                                          false, filter);
1749         }
1750
1751         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1752                 err = dso__load_vmlinux_path(dso, map, filter);
1753                 if (err > 0)
1754                         return err;
1755         }
1756
1757         /* do not try local files if a symfs was given */
1758         if (symbol_conf.symfs[0] != 0)
1759                 return -1;
1760
1761         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1762         if (!kallsyms_allocated_filename)
1763                 return -1;
1764
1765         kallsyms_filename = kallsyms_allocated_filename;
1766
1767 do_kallsyms:
1768         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1769         if (err > 0)
1770                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1771         free(kallsyms_allocated_filename);
1772
1773         if (err > 0 && !dso__is_kcore(dso)) {
1774                 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
1775                 dso__set_long_name(dso, "[kernel.kallsyms]", false);
1776                 map__fixup_start(map);
1777                 map__fixup_end(map);
1778         }
1779
1780         return err;
1781 }
1782
1783 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1784                                       symbol_filter_t filter)
1785 {
1786         int err;
1787         const char *kallsyms_filename = NULL;
1788         struct machine *machine;
1789         char path[PATH_MAX];
1790
1791         if (!map->groups) {
1792                 pr_debug("Guest kernel map hasn't the point to groups\n");
1793                 return -1;
1794         }
1795         machine = map->groups->machine;
1796
1797         if (machine__is_default_guest(machine)) {
1798                 /*
1799                  * if the user specified a vmlinux filename, use it and only
1800                  * it, reporting errors to the user if it cannot be used.
1801                  * Or use file guest_kallsyms inputted by user on commandline
1802                  */
1803                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1804                         err = dso__load_vmlinux(dso, map,
1805                                                 symbol_conf.default_guest_vmlinux_name,
1806                                                 false, filter);
1807                         return err;
1808                 }
1809
1810                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1811                 if (!kallsyms_filename)
1812                         return -1;
1813         } else {
1814                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1815                 kallsyms_filename = path;
1816         }
1817
1818         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1819         if (err > 0)
1820                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1821         if (err > 0 && !dso__is_kcore(dso)) {
1822                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1823                 machine__mmap_name(machine, path, sizeof(path));
1824                 dso__set_long_name(dso, strdup(path), true);
1825                 map__fixup_start(map);
1826                 map__fixup_end(map);
1827         }
1828
1829         return err;
1830 }
1831
1832 static void vmlinux_path__exit(void)
1833 {
1834         while (--vmlinux_path__nr_entries >= 0)
1835                 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1836         vmlinux_path__nr_entries = 0;
1837
1838         zfree(&vmlinux_path);
1839 }
1840
1841 static int vmlinux_path__init(struct perf_session_env *env)
1842 {
1843         struct utsname uts;
1844         char bf[PATH_MAX];
1845         char *kernel_version;
1846
1847         vmlinux_path = malloc(sizeof(char *) * 6);
1848         if (vmlinux_path == NULL)
1849                 return -1;
1850
1851         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1852         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1853                 goto out_fail;
1854         ++vmlinux_path__nr_entries;
1855         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1856         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1857                 goto out_fail;
1858         ++vmlinux_path__nr_entries;
1859
1860         /* only try kernel version if no symfs was given */
1861         if (symbol_conf.symfs[0] != 0)
1862                 return 0;
1863
1864         if (env) {
1865                 kernel_version = env->os_release;
1866         } else {
1867                 if (uname(&uts) < 0)
1868                         goto out_fail;
1869
1870                 kernel_version = uts.release;
1871         }
1872
1873         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", kernel_version);
1874         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1875         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1876                 goto out_fail;
1877         ++vmlinux_path__nr_entries;
1878         snprintf(bf, sizeof(bf), "/usr/lib/debug/boot/vmlinux-%s",
1879                  kernel_version);
1880         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1881         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1882                 goto out_fail;
1883         ++vmlinux_path__nr_entries;
1884         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", kernel_version);
1885         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1886         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1887                 goto out_fail;
1888         ++vmlinux_path__nr_entries;
1889         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1890                  kernel_version);
1891         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1892         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1893                 goto out_fail;
1894         ++vmlinux_path__nr_entries;
1895
1896         return 0;
1897
1898 out_fail:
1899         vmlinux_path__exit();
1900         return -1;
1901 }
1902
1903 int setup_list(struct strlist **list, const char *list_str,
1904                       const char *list_name)
1905 {
1906         if (list_str == NULL)
1907                 return 0;
1908
1909         *list = strlist__new(true, list_str);
1910         if (!*list) {
1911                 pr_err("problems parsing %s list\n", list_name);
1912                 return -1;
1913         }
1914         return 0;
1915 }
1916
1917 int setup_intlist(struct intlist **list, const char *list_str,
1918                   const char *list_name)
1919 {
1920         if (list_str == NULL)
1921                 return 0;
1922
1923         *list = intlist__new(list_str);
1924         if (!*list) {
1925                 pr_err("problems parsing %s list\n", list_name);
1926                 return -1;
1927         }
1928         return 0;
1929 }
1930
1931 static bool symbol__read_kptr_restrict(void)
1932 {
1933         bool value = false;
1934
1935         if (geteuid() != 0) {
1936                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1937                 if (fp != NULL) {
1938                         char line[8];
1939
1940                         if (fgets(line, sizeof(line), fp) != NULL)
1941                                 value = atoi(line) != 0;
1942
1943                         fclose(fp);
1944                 }
1945         }
1946
1947         return value;
1948 }
1949
1950 int symbol__init(struct perf_session_env *env)
1951 {
1952         const char *symfs;
1953
1954         if (symbol_conf.initialized)
1955                 return 0;
1956
1957         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1958
1959         symbol__elf_init();
1960
1961         if (symbol_conf.sort_by_name)
1962                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1963                                           sizeof(struct symbol));
1964
1965         if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
1966                 return -1;
1967
1968         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1969                 pr_err("'.' is the only non valid --field-separator argument\n");
1970                 return -1;
1971         }
1972
1973         if (setup_list(&symbol_conf.dso_list,
1974                        symbol_conf.dso_list_str, "dso") < 0)
1975                 return -1;
1976
1977         if (setup_list(&symbol_conf.comm_list,
1978                        symbol_conf.comm_list_str, "comm") < 0)
1979                 goto out_free_dso_list;
1980
1981         if (setup_intlist(&symbol_conf.pid_list,
1982                        symbol_conf.pid_list_str, "pid") < 0)
1983                 goto out_free_comm_list;
1984
1985         if (setup_intlist(&symbol_conf.tid_list,
1986                        symbol_conf.tid_list_str, "tid") < 0)
1987                 goto out_free_pid_list;
1988
1989         if (setup_list(&symbol_conf.sym_list,
1990                        symbol_conf.sym_list_str, "symbol") < 0)
1991                 goto out_free_tid_list;
1992
1993         /*
1994          * A path to symbols of "/" is identical to ""
1995          * reset here for simplicity.
1996          */
1997         symfs = realpath(symbol_conf.symfs, NULL);
1998         if (symfs == NULL)
1999                 symfs = symbol_conf.symfs;
2000         if (strcmp(symfs, "/") == 0)
2001                 symbol_conf.symfs = "";
2002         if (symfs != symbol_conf.symfs)
2003                 free((void *)symfs);
2004
2005         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2006
2007         symbol_conf.initialized = true;
2008         return 0;
2009
2010 out_free_tid_list:
2011         intlist__delete(symbol_conf.tid_list);
2012 out_free_pid_list:
2013         intlist__delete(symbol_conf.pid_list);
2014 out_free_comm_list:
2015         strlist__delete(symbol_conf.comm_list);
2016 out_free_dso_list:
2017         strlist__delete(symbol_conf.dso_list);
2018         return -1;
2019 }
2020
2021 void symbol__exit(void)
2022 {
2023         if (!symbol_conf.initialized)
2024                 return;
2025         strlist__delete(symbol_conf.sym_list);
2026         strlist__delete(symbol_conf.dso_list);
2027         strlist__delete(symbol_conf.comm_list);
2028         intlist__delete(symbol_conf.tid_list);
2029         intlist__delete(symbol_conf.pid_list);
2030         vmlinux_path__exit();
2031         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2032         symbol_conf.initialized = false;
2033 }