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
  19 #include <elf.h>
  20 #include <limits.h>
  21 #include <sys/utsname.h>
  22
  23 #ifndef KSYM_NAME_LEN
  24 #define KSYM_NAME_LEN 256
  25 #endif
  26
  27 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
  28                                 symbol_filter_t filter);
  29 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
  30                         symbol_filter_t filter);
  31 int vmlinux_path__nr_entries;
  32 char **vmlinux_path;
  33
  34 struct symbol_conf symbol_conf = {
  35         .use_modules      = true,
  36         .try_vmlinux_path = true,
  37         .annotate_src     = true,
  38         .demangle         = true,
  39         .symfs            = "",
  40 };
  41
  42 static enum dso_binary_type binary_type_symtab[] = {
  43         DSO_BINARY_TYPE__KALLSYMS,
  44         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  45         DSO_BINARY_TYPE__JAVA_JIT,
  46         DSO_BINARY_TYPE__DEBUGLINK,
  47         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  48         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  49         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  50         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  51         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  52         DSO_BINARY_TYPE__GUEST_KMODULE,
  53         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  54         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  55         DSO_BINARY_TYPE__NOT_FOUND,
  56 };
  57
  58 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  59
  60 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
  61 {
  62         symbol_type = toupper(symbol_type);
  63
  64         switch (map_type) {
  65         case MAP__FUNCTION:
  66                 return symbol_type == 'T' || symbol_type == 'W';
  67         case MAP__VARIABLE:
  68                 return symbol_type == 'D';
  69         default:
  70                 return false;
  71         }
  72 }
  73
  74 static int prefix_underscores_count(const char *str)
  75 {
  76         const char *tail = str;
  77
  78         while (*tail == '_')
  79                 tail++;
  80
  81         return tail - str;
  82 }
  83
  84 #define SYMBOL_A 0
  85 #define SYMBOL_B 1
  86
  87 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
  88 {
  89         s64 a;
  90         s64 b;
  91         size_t na, nb;
  92
  93         /* Prefer a symbol with non zero length */
  94         a = syma->end - syma->start;
  95         b = symb->end - symb->start;
  96         if ((b == 0) && (a > 0))
  97                 return SYMBOL_A;
  98         else if ((a == 0) && (b > 0))
  99                 return SYMBOL_B;
 100
 101         /* Prefer a non weak symbol over a weak one */
 102         a = syma->binding == STB_WEAK;
 103         b = symb->binding == STB_WEAK;
 104         if (b && !a)
 105                 return SYMBOL_A;
 106         if (a && !b)
 107                 return SYMBOL_B;
 108
 109         /* Prefer a global symbol over a non global one */
 110         a = syma->binding == STB_GLOBAL;
 111         b = symb->binding == STB_GLOBAL;
 112         if (a && !b)
 113                 return SYMBOL_A;
 114         if (b && !a)
 115                 return SYMBOL_B;
 116
 117         /* Prefer a symbol with less underscores */
 118         a = prefix_underscores_count(syma->name);
 119         b = prefix_underscores_count(symb->name);
 120         if (b > a)
 121                 return SYMBOL_A;
 122         else if (a > b)
 123                 return SYMBOL_B;
 124
 125         /* Choose the symbol with the longest name */
 126         na = strlen(syma->name);
 127         nb = strlen(symb->name);
 128         if (na > nb)
 129                 return SYMBOL_A;
 130         else if (na < nb)
 131                 return SYMBOL_B;
 132
 133         /* Avoid "SyS" kernel syscall aliases */
 134         if (na >= 3 && !strncmp(syma->name, "SyS", 3))
 135                 return SYMBOL_B;
 136         if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
 137                 return SYMBOL_B;
 138
 139         return SYMBOL_A;
 140 }
 141
 142 void symbols__fixup_duplicate(struct rb_root *symbols)
 143 {
 144         struct rb_node *nd;
 145         struct symbol *curr, *next;
 146
 147         nd = rb_first(symbols);
 148
 149         while (nd) {
 150                 curr = rb_entry(nd, struct symbol, rb_node);
 151 again:
 152                 nd = rb_next(&curr->rb_node);
 153                 next = rb_entry(nd, struct symbol, rb_node);
 154
 155                 if (!nd)
 156                         break;
 157
 158                 if (curr->start != next->start)
 159                         continue;
 160
 161                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 162                         rb_erase(&next->rb_node, symbols);
 163                         goto again;
 164                 } else {
 165                         nd = rb_next(&curr->rb_node);
 166                         rb_erase(&curr->rb_node, symbols);
 167                 }
 168         }
 169 }
 170
 171 void symbols__fixup_end(struct rb_root *symbols)
 172 {
 173         struct rb_node *nd, *prevnd = rb_first(symbols);
 174         struct symbol *curr, *prev;
 175
 176         if (prevnd == NULL)
 177                 return;
 178
 179         curr = rb_entry(prevnd, struct symbol, rb_node);
 180
 181         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 182                 prev = curr;
 183                 curr = rb_entry(nd, struct symbol, rb_node);
 184
 185                 if (prev->end == prev->start && prev->end != curr->start)
 186                         prev->end = curr->start - 1;
 187         }
 188
 189         /* Last entry */
 190         if (curr->end == curr->start)
 191                 curr->end = roundup(curr->start, 4096);
 192 }
 193
 194 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
 195 {
 196         struct map *prev, *curr;
 197         struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
 198
 199         if (prevnd == NULL)
 200                 return;
 201
 202         curr = rb_entry(prevnd, struct map, rb_node);
 203
 204         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 205                 prev = curr;
 206                 curr = rb_entry(nd, struct map, rb_node);
 207                 prev->end = curr->start - 1;
 208         }
 209
 210         /*
 211          * We still haven't the actual symbols, so guess the
 212          * last map final address.
 213          */
 214         curr->end = ~0ULL;
 215 }
 216
 217 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
 218 {
 219         size_t namelen = strlen(name) + 1;
 220         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 221                                         sizeof(*sym) + namelen));
 222         if (sym == NULL)
 223                 return NULL;
 224
 225         if (symbol_conf.priv_size)
 226                 sym = ((void *)sym) + symbol_conf.priv_size;
 227
 228         sym->start   = start;
 229         sym->end     = len ? start + len - 1 : start;
 230         sym->binding = binding;
 231         sym->namelen = namelen - 1;
 232
 233         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 234                   __func__, name, start, sym->end);
 235         memcpy(sym->name, name, namelen);
 236
 237         return sym;
 238 }
 239
 240 void symbol__delete(struct symbol *sym)
 241 {
 242         free(((void *)sym) - symbol_conf.priv_size);
 243 }
 244
 245 size_t symbol__fprintf(struct symbol *sym, FILE *fp)
 246 {
 247         return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
 248                        sym->start, sym->end,
 249                        sym->binding == STB_GLOBAL ? 'g' :
 250                        sym->binding == STB_LOCAL  ? 'l' : 'w',
 251                        sym->name);
 252 }
 253
 254 size_t symbol__fprintf_symname_offs(const struct symbol *sym,
 255                                     const struct addr_location *al, FILE *fp)
 256 {
 257         unsigned long offset;
 258         size_t length;
 259
 260         if (sym && sym->name) {
 261                 length = fprintf(fp, "%s", sym->name);
 262                 if (al) {
 263                         if (al->addr < sym->end)
 264                                 offset = al->addr - sym->start;
 265                         else
 266                                 offset = al->addr - al->map->start - sym->start;
 267                         length += fprintf(fp, "+0x%lx", offset);
 268                 }
 269                 return length;
 270         } else
 271                 return fprintf(fp, "[unknown]");
 272 }
 273
 274 size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
 275 {
 276         return symbol__fprintf_symname_offs(sym, NULL, fp);
 277 }
 278
 279 void symbols__delete(struct rb_root *symbols)
 280 {
 281         struct symbol *pos;
 282         struct rb_node *next = rb_first(symbols);
 283
 284         while (next) {
 285                 pos = rb_entry(next, struct symbol, rb_node);
 286                 next = rb_next(&pos->rb_node);
 287                 rb_erase(&pos->rb_node, symbols);
 288                 symbol__delete(pos);
 289         }
 290 }
 291
 292 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
 293 {
 294         struct rb_node **p = &symbols->rb_node;
 295         struct rb_node *parent = NULL;
 296         const u64 ip = sym->start;
 297         struct symbol *s;
 298
 299         while (*p != NULL) {
 300                 parent = *p;
 301                 s = rb_entry(parent, struct symbol, rb_node);
 302                 if (ip < s->start)
 303                         p = &(*p)->rb_left;
 304                 else
 305                         p = &(*p)->rb_right;
 306         }
 307         rb_link_node(&sym->rb_node, parent, p);
 308         rb_insert_color(&sym->rb_node, symbols);
 309 }
 310
 311 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
 312 {
 313         struct rb_node *n;
 314
 315         if (symbols == NULL)
 316                 return NULL;
 317
 318         n = symbols->rb_node;
 319
 320         while (n) {
 321                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 322
 323                 if (ip < s->start)
 324                         n = n->rb_left;
 325                 else if (ip > s->end)
 326                         n = n->rb_right;
 327                 else
 328                         return s;
 329         }
 330
 331         return NULL;
 332 }
 333
 334 static struct symbol *symbols__first(struct rb_root *symbols)
 335 {
 336         struct rb_node *n = rb_first(symbols);
 337
 338         if (n)
 339                 return rb_entry(n, struct symbol, rb_node);
 340
 341         return NULL;
 342 }
 343
 344 struct symbol_name_rb_node {
 345         struct rb_node  rb_node;
 346         struct symbol   sym;
 347 };
 348
 349 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
 350 {
 351         struct rb_node **p = &symbols->rb_node;
 352         struct rb_node *parent = NULL;
 353         struct symbol_name_rb_node *symn, *s;
 354
 355         symn = container_of(sym, struct symbol_name_rb_node, sym);
 356
 357         while (*p != NULL) {
 358                 parent = *p;
 359                 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
 360                 if (strcmp(sym->name, s->sym.name) < 0)
 361                         p = &(*p)->rb_left;
 362                 else
 363                         p = &(*p)->rb_right;
 364         }
 365         rb_link_node(&symn->rb_node, parent, p);
 366         rb_insert_color(&symn->rb_node, symbols);
 367 }
 368
 369 static void symbols__sort_by_name(struct rb_root *symbols,
 370                                   struct rb_root *source)
 371 {
 372         struct rb_node *nd;
 373
 374         for (nd = rb_first(source); nd; nd = rb_next(nd)) {
 375                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 376                 symbols__insert_by_name(symbols, pos);
 377         }
 378 }
 379
 380 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
 381                                             const char *name)
 382 {
 383         struct rb_node *n;
 384
 385         if (symbols == NULL)
 386                 return NULL;
 387
 388         n = symbols->rb_node;
 389
 390         while (n) {
 391                 struct symbol_name_rb_node *s;
 392                 int cmp;
 393
 394                 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
 395                 cmp = strcmp(name, s->sym.name);
 396
 397                 if (cmp < 0)
 398                         n = n->rb_left;
 399                 else if (cmp > 0)
 400                         n = n->rb_right;
 401                 else
 402                         return &s->sym;
 403         }
 404
 405         return NULL;
 406 }
 407
 408 struct symbol *dso__find_symbol(struct dso *dso,
 409                                 enum map_type type, u64 addr)
 410 {
 411         return symbols__find(&dso->symbols[type], addr);
 412 }
 413
 414 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
 415 {
 416         return symbols__first(&dso->symbols[type]);
 417 }
 418
 419 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
 420                                         const char *name)
 421 {
 422         return symbols__find_by_name(&dso->symbol_names[type], name);
 423 }
 424
 425 void dso__sort_by_name(struct dso *dso, enum map_type type)
 426 {
 427         dso__set_sorted_by_name(dso, type);
 428         return symbols__sort_by_name(&dso->symbol_names[type],
 429                                      &dso->symbols[type]);
 430 }
 431
 432 size_t dso__fprintf_symbols_by_name(struct dso *dso,
 433                                     enum map_type type, FILE *fp)
 434 {
 435         size_t ret = 0;
 436         struct rb_node *nd;
 437         struct symbol_name_rb_node *pos;
 438
 439         for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
 440                 pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
 441                 fprintf(fp, "%s\n", pos->sym.name);
 442         }
 443
 444         return ret;
 445 }
 446
 447 int kallsyms__parse(const char *filename, void *arg,
 448                     int (*process_symbol)(void *arg, const char *name,
 449                                           char type, u64 start))
 450 {
 451         char *line = NULL;
 452         size_t n;
 453         int err = -1;
 454         FILE *file = fopen(filename, "r");
 455
 456         if (file == NULL)
 457                 goto out_failure;
 458
 459         err = 0;
 460
 461         while (!feof(file)) {
 462                 u64 start;
 463                 int line_len, len;
 464                 char symbol_type;
 465                 char *symbol_name;
 466
 467                 line_len = getline(&line, &n, file);
 468                 if (line_len < 0 || !line)
 469                         break;
 470
 471                 line[--line_len] = '\0'; /* \n */
 472
 473                 len = hex2u64(line, &start);
 474
 475                 len++;
 476                 if (len + 2 >= line_len)
 477                         continue;
 478
 479                 symbol_type = line[len];
 480                 len += 2;
 481                 symbol_name = line + len;
 482                 len = line_len - len;
 483
 484                 if (len >= KSYM_NAME_LEN) {
 485                         err = -1;
 486                         break;
 487                 }
 488
 489                 err = process_symbol(arg, symbol_name,
 490                                      symbol_type, start);
 491                 if (err)
 492                         break;
 493         }
 494
 495         free(line);
 496         fclose(file);
 497         return err;
 498
 499 out_failure:
 500         return -1;
 501 }
 502
 503 int modules__parse(const char *filename, void *arg,
 504                    int (*process_module)(void *arg, const char *name,
 505                                          u64 start))
 506 {
 507         char *line = NULL;
 508         size_t n;
 509         FILE *file;
 510         int err = 0;
 511
 512         file = fopen(filename, "r");
 513         if (file == NULL)
 514                 return -1;
 515
 516         while (1) {
 517                 char name[PATH_MAX];
 518                 u64 start;
 519                 char *sep;
 520                 ssize_t line_len;
 521
 522                 line_len = getline(&line, &n, file);
 523                 if (line_len < 0) {
 524                         if (feof(file))
 525                                 break;
 526                         err = -1;
 527                         goto out;
 528                 }
 529
 530                 if (!line) {
 531                         err = -1;
 532                         goto out;
 533                 }
 534
 535                 line[--line_len] = '\0'; /* \n */
 536
 537                 sep = strrchr(line, 'x');
 538                 if (sep == NULL)
 539                         continue;
 540
 541                 hex2u64(sep + 1, &start);
 542
 543                 sep = strchr(line, ' ');
 544                 if (sep == NULL)
 545                         continue;
 546
 547                 *sep = '\0';
 548
 549                 scnprintf(name, sizeof(name), "[%s]", line);
 550
 551                 err = process_module(arg, name, start);
 552                 if (err)
 553                         break;
 554         }
 555 out:
 556         free(line);
 557         fclose(file);
 558         return err;
 559 }
 560
 561 struct process_kallsyms_args {
 562         struct map *map;
 563         struct dso *dso;
 564 };
 565
 566 static u8 kallsyms2elf_type(char type)
 567 {
 568         if (type == 'W')
 569                 return STB_WEAK;
 570
 571         return isupper(type) ? STB_GLOBAL : STB_LOCAL;
 572 }
 573
 574 static int map__process_kallsym_symbol(void *arg, const char *name,
 575                                        char type, u64 start)
 576 {
 577         struct symbol *sym;
 578         struct process_kallsyms_args *a = arg;
 579         struct rb_root *root = &a->dso->symbols[a->map->type];
 580
 581         if (!symbol_type__is_a(type, a->map->type))
 582                 return 0;
 583
 584         /*
 585          * module symbols are not sorted so we add all
 586          * symbols, setting length to 0, and rely on
 587          * symbols__fixup_end() to fix it up.
 588          */
 589         sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
 590         if (sym == NULL)
 591                 return -ENOMEM;
 592         /*
 593          * We will pass the symbols to the filter later, in
 594          * map__split_kallsyms, when we have split the maps per module
 595          */
 596         symbols__insert(root, sym);
 597
 598         return 0;
 599 }
 600
 601 /*
 602  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 603  * so that we can in the next step set the symbol ->end address and then
 604  * call kernel_maps__split_kallsyms.
 605  */
 606 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
 607                                   struct map *map)
 608 {
 609         struct process_kallsyms_args args = { .map = map, .dso = dso, };
 610         return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
 611 }
 612
 613 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
 614                                          symbol_filter_t filter)
 615 {
 616         struct map_groups *kmaps = map__kmap(map)->kmaps;
 617         struct map *curr_map;
 618         struct symbol *pos;
 619         int count = 0, moved = 0;
 620         struct rb_root *root = &dso->symbols[map->type];
 621         struct rb_node *next = rb_first(root);
 622
 623         while (next) {
 624                 char *module;
 625
 626                 pos = rb_entry(next, struct symbol, rb_node);
 627                 next = rb_next(&pos->rb_node);
 628
 629                 module = strchr(pos->name, '\t');
 630                 if (module)
 631                         *module = '\0';
 632
 633                 curr_map = map_groups__find(kmaps, map->type, pos->start);
 634
 635                 if (!curr_map || (filter && filter(curr_map, pos))) {
 636                         rb_erase(&pos->rb_node, root);
 637                         symbol__delete(pos);
 638                 } else {
 639                         pos->start -= curr_map->start - curr_map->pgoff;
 640                         if (pos->end)
 641                                 pos->end -= curr_map->start - curr_map->pgoff;
 642                         if (curr_map != map) {
 643                                 rb_erase(&pos->rb_node, root);
 644                                 symbols__insert(
 645                                         &curr_map->dso->symbols[curr_map->type],
 646                                         pos);
 647                                 ++moved;
 648                         } else {
 649                                 ++count;
 650                         }
 651                 }
 652         }
 653
 654         /* Symbols have been adjusted */
 655         dso->adjust_symbols = 1;
 656
 657         return count + moved;
 658 }
 659
 660 /*
 661  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 662  * kernel range is broken in several maps, named [kernel].N, as we don't have
 663  * the original ELF section names vmlinux have.
 664  */
 665 static int dso__split_kallsyms(struct dso *dso, struct map *map,
 666                                symbol_filter_t filter)
 667 {
 668         struct map_groups *kmaps = map__kmap(map)->kmaps;
 669         struct machine *machine = kmaps->machine;
 670         struct map *curr_map = map;
 671         struct symbol *pos;
 672         int count = 0, moved = 0;
 673         struct rb_root *root = &dso->symbols[map->type];
 674         struct rb_node *next = rb_first(root);
 675         int kernel_range = 0;
 676
 677         while (next) {
 678                 char *module;
 679
 680                 pos = rb_entry(next, struct symbol, rb_node);
 681                 next = rb_next(&pos->rb_node);
 682
 683                 module = strchr(pos->name, '\t');
 684                 if (module) {
 685                         if (!symbol_conf.use_modules)
 686                                 goto discard_symbol;
 687
 688                         *module++ = '\0';
 689
 690                         if (strcmp(curr_map->dso->short_name, module)) {
 691                                 if (curr_map != map &&
 692                                     dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 693                                     machine__is_default_guest(machine)) {
 694                                         /*
 695                                          * We assume all symbols of a module are
 696                                          * continuous in * kallsyms, so curr_map
 697                                          * points to a module and all its
 698                                          * symbols are in its kmap. Mark it as
 699                                          * loaded.
 700                                          */
 701                                         dso__set_loaded(curr_map->dso,
 702                                                         curr_map->type);
 703                                 }
 704
 705                                 curr_map = map_groups__find_by_name(kmaps,
 706                                                         map->type, module);
 707                                 if (curr_map == NULL) {
 708                                         pr_debug("%s/proc/{kallsyms,modules} "
 709                                                  "inconsistency while looking "
 710                                                  "for \"%s\" module!\n",
 711                                                  machine->root_dir, module);
 712                                         curr_map = map;
 713                                         goto discard_symbol;
 714                                 }
 715
 716                                 if (curr_map->dso->loaded &&
 717                                     !machine__is_default_guest(machine))
 718                                         goto discard_symbol;
 719                         }
 720                         /*
 721                          * So that we look just like we get from .ko files,
 722                          * i.e. not prelinked, relative to map->start.
 723                          */
 724                         pos->start = curr_map->map_ip(curr_map, pos->start);
 725                         pos->end   = curr_map->map_ip(curr_map, pos->end);
 726                 } else if (curr_map != map) {
 727                         char dso_name[PATH_MAX];
 728                         struct dso *ndso;
 729
 730                         if (count == 0) {
 731                                 curr_map = map;
 732                                 goto filter_symbol;
 733                         }
 734
 735                         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
 736                                 snprintf(dso_name, sizeof(dso_name),
 737                                         "[guest.kernel].%d",
 738                                         kernel_range++);
 739                         else
 740                                 snprintf(dso_name, sizeof(dso_name),
 741                                         "[kernel].%d",
 742                                         kernel_range++);
 743
 744                         ndso = dso__new(dso_name);
 745                         if (ndso == NULL)
 746                                 return -1;
 747
 748                         ndso->kernel = dso->kernel;
 749
 750                         curr_map = map__new2(pos->start, ndso, map->type);
 751                         if (curr_map == NULL) {
 752                                 dso__delete(ndso);
 753                                 return -1;
 754                         }
 755
 756                         curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
 757                         map_groups__insert(kmaps, curr_map);
 758                         ++kernel_range;
 759                 }
 760 filter_symbol:
 761                 if (filter && filter(curr_map, pos)) {
 762 discard_symbol:         rb_erase(&pos->rb_node, root);
 763                         symbol__delete(pos);
 764                 } else {
 765                         if (curr_map != map) {
 766                                 rb_erase(&pos->rb_node, root);
 767                                 symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
 768                                 ++moved;
 769                         } else
 770                                 ++count;
 771                 }
 772         }
 773
 774         if (curr_map != map &&
 775             dso->kernel == DSO_TYPE_GUEST_KERNEL &&
 776             machine__is_default_guest(kmaps->machine)) {
 777                 dso__set_loaded(curr_map->dso, curr_map->type);
 778         }
 779
 780         return count + moved;
 781 }
 782
 783 bool symbol__restricted_filename(const char *filename,
 784                                  const char *restricted_filename)
 785 {
 786         bool restricted = false;
 787
 788         if (symbol_conf.kptr_restrict) {
 789                 char *r = realpath(filename, NULL);
 790
 791                 if (r != NULL) {
 792                         restricted = strcmp(r, restricted_filename) == 0;
 793                         free(r);
 794                         return restricted;
 795                 }
 796         }
 797
 798         return restricted;
 799 }
 800
 801 struct module_info {
 802         struct rb_node rb_node;
 803         char *name;
 804         u64 start;
 805 };
 806
 807 static void add_module(struct module_info *mi, struct rb_root *modules)
 808 {
 809         struct rb_node **p = &modules->rb_node;
 810         struct rb_node *parent = NULL;
 811         struct module_info *m;
 812
 813         while (*p != NULL) {
 814                 parent = *p;
 815                 m = rb_entry(parent, struct module_info, rb_node);
 816                 if (strcmp(mi->name, m->name) < 0)
 817                         p = &(*p)->rb_left;
 818                 else
 819                         p = &(*p)->rb_right;
 820         }
 821         rb_link_node(&mi->rb_node, parent, p);
 822         rb_insert_color(&mi->rb_node, modules);
 823 }
 824
 825 static void delete_modules(struct rb_root *modules)
 826 {
 827         struct module_info *mi;
 828         struct rb_node *next = rb_first(modules);
 829
 830         while (next) {
 831                 mi = rb_entry(next, struct module_info, rb_node);
 832                 next = rb_next(&mi->rb_node);
 833                 rb_erase(&mi->rb_node, modules);
 834                 free(mi->name);
 835                 free(mi);
 836         }
 837 }
 838
 839 static struct module_info *find_module(const char *name,
 840                                        struct rb_root *modules)
 841 {
 842         struct rb_node *n = modules->rb_node;
 843
 844         while (n) {
 845                 struct module_info *m;
 846                 int cmp;
 847
 848                 m = rb_entry(n, struct module_info, rb_node);
 849                 cmp = strcmp(name, m->name);
 850                 if (cmp < 0)
 851                         n = n->rb_left;
 852                 else if (cmp > 0)
 853                         n = n->rb_right;
 854                 else
 855                         return m;
 856         }
 857
 858         return NULL;
 859 }
 860
 861 static int __read_proc_modules(void *arg, const char *name, u64 start)
 862 {
 863         struct rb_root *modules = arg;
 864         struct module_info *mi;
 865
 866         mi = zalloc(sizeof(struct module_info));
 867         if (!mi)
 868                 return -ENOMEM;
 869
 870         mi->name = strdup(name);
 871         mi->start = start;
 872
 873         if (!mi->name) {
 874                 free(mi);
 875                 return -ENOMEM;
 876         }
 877
 878         add_module(mi, modules);
 879
 880         return 0;
 881 }
 882
 883 static int read_proc_modules(const char *filename, struct rb_root *modules)
 884 {
 885         if (symbol__restricted_filename(filename, "/proc/modules"))
 886                 return -1;
 887
 888         if (modules__parse(filename, modules, __read_proc_modules)) {
 889                 delete_modules(modules);
 890                 return -1;
 891         }
 892
 893         return 0;
 894 }
 895
 896 int compare_proc_modules(const char *from, const char *to)
 897 {
 898         struct rb_root from_modules = RB_ROOT;
 899         struct rb_root to_modules = RB_ROOT;
 900         struct rb_node *from_node, *to_node;
 901         struct module_info *from_m, *to_m;
 902         int ret = -1;
 903
 904         if (read_proc_modules(from, &from_modules))
 905                 return -1;
 906
 907         if (read_proc_modules(to, &to_modules))
 908                 goto out_delete_from;
 909
 910         from_node = rb_first(&from_modules);
 911         to_node = rb_first(&to_modules);
 912         while (from_node) {
 913                 if (!to_node)
 914                         break;
 915
 916                 from_m = rb_entry(from_node, struct module_info, rb_node);
 917                 to_m = rb_entry(to_node, struct module_info, rb_node);
 918
 919                 if (from_m->start != to_m->start ||
 920                     strcmp(from_m->name, to_m->name))
 921                         break;
 922
 923                 from_node = rb_next(from_node);
 924                 to_node = rb_next(to_node);
 925         }
 926
 927         if (!from_node && !to_node)
 928                 ret = 0;
 929
 930         delete_modules(&to_modules);
 931 out_delete_from:
 932         delete_modules(&from_modules);
 933
 934         return ret;
 935 }
 936
 937 static int do_validate_kcore_modules(const char *filename, struct map *map,
 938                                   struct map_groups *kmaps)
 939 {
 940         struct rb_root modules = RB_ROOT;
 941         struct map *old_map;
 942         int err;
 943
 944         err = read_proc_modules(filename, &modules);
 945         if (err)
 946                 return err;
 947
 948         old_map = map_groups__first(kmaps, map->type);
 949         while (old_map) {
 950                 struct map *next = map_groups__next(old_map);
 951                 struct module_info *mi;
 952
 953                 if (old_map == map || old_map->start == map->start) {
 954                         /* The kernel map */
 955                         old_map = next;
 956                         continue;
 957                 }
 958
 959                 /* Module must be in memory at the same address */
 960                 mi = find_module(old_map->dso->short_name, &modules);
 961                 if (!mi || mi->start != old_map->start) {
 962                         err = -EINVAL;
 963                         goto out;
 964                 }
 965
 966                 old_map = next;
 967         }
 968 out:
 969         delete_modules(&modules);
 970         return err;
 971 }
 972
 973 /*
 974  * If kallsyms is referenced by name then we look for filename in the same
 975  * directory.
 976  */
 977 static bool filename_from_kallsyms_filename(char *filename,
 978                                             const char *base_name,
 979                                             const char *kallsyms_filename)
 980 {
 981         char *name;
 982
 983         strcpy(filename, kallsyms_filename);
 984         name = strrchr(filename, '/');
 985         if (!name)
 986                 return false;
 987
 988         name += 1;
 989
 990         if (!strcmp(name, "kallsyms")) {
 991                 strcpy(name, base_name);
 992                 return true;
 993         }
 994
 995         return false;
 996 }
 997
 998 static int validate_kcore_modules(const char *kallsyms_filename,
 999                                   struct map *map)
1000 {
1001         struct map_groups *kmaps = map__kmap(map)->kmaps;
1002         char modules_filename[PATH_MAX];
1003
1004         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1005                                              kallsyms_filename))
1006                 return -EINVAL;
1007
1008         if (do_validate_kcore_modules(modules_filename, map, kmaps))
1009                 return -EINVAL;
1010
1011         return 0;
1012 }
1013
1014 struct kcore_mapfn_data {
1015         struct dso *dso;
1016         enum map_type type;
1017         struct list_head maps;
1018 };
1019
1020 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1021 {
1022         struct kcore_mapfn_data *md = data;
1023         struct map *map;
1024
1025         map = map__new2(start, md->dso, md->type);
1026         if (map == NULL)
1027                 return -ENOMEM;
1028
1029         map->end = map->start + len;
1030         map->pgoff = pgoff;
1031
1032         list_add(&map->node, &md->maps);
1033
1034         return 0;
1035 }
1036
1037 static int dso__load_kcore(struct dso *dso, struct map *map,
1038                            const char *kallsyms_filename)
1039 {
1040         struct map_groups *kmaps = map__kmap(map)->kmaps;
1041         struct machine *machine = kmaps->machine;
1042         struct kcore_mapfn_data md;
1043         struct map *old_map, *new_map, *replacement_map = NULL;
1044         bool is_64_bit;
1045         int err, fd;
1046         char kcore_filename[PATH_MAX];
1047         struct symbol *sym;
1048
1049         /* This function requires that the map is the kernel map */
1050         if (map != machine->vmlinux_maps[map->type])
1051                 return -EINVAL;
1052
1053         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1054                                              kallsyms_filename))
1055                 return -EINVAL;
1056
1057         /* All modules must be present at their original addresses */
1058         if (validate_kcore_modules(kallsyms_filename, map))
1059                 return -EINVAL;
1060
1061         md.dso = dso;
1062         md.type = map->type;
1063         INIT_LIST_HEAD(&md.maps);
1064
1065         fd = open(kcore_filename, O_RDONLY);
1066         if (fd < 0)
1067                 return -EINVAL;
1068
1069         /* Read new maps into temporary lists */
1070         err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1071                               &is_64_bit);
1072         if (err)
1073                 goto out_err;
1074
1075         if (list_empty(&md.maps)) {
1076                 err = -EINVAL;
1077                 goto out_err;
1078         }
1079
1080         /* Remove old maps */
1081         old_map = map_groups__first(kmaps, map->type);
1082         while (old_map) {
1083                 struct map *next = map_groups__next(old_map);
1084
1085                 if (old_map != map)
1086                         map_groups__remove(kmaps, old_map);
1087                 old_map = next;
1088         }
1089
1090         /* Find the kernel map using the first symbol */
1091         sym = dso__first_symbol(dso, map->type);
1092         list_for_each_entry(new_map, &md.maps, node) {
1093                 if (sym && sym->start >= new_map->start &&
1094                     sym->start < new_map->end) {
1095                         replacement_map = new_map;
1096                         break;
1097                 }
1098         }
1099
1100         if (!replacement_map)
1101                 replacement_map = list_entry(md.maps.next, struct map, node);
1102
1103         /* Add new maps */
1104         while (!list_empty(&md.maps)) {
1105                 new_map = list_entry(md.maps.next, struct map, node);
1106                 list_del(&new_map->node);
1107                 if (new_map == replacement_map) {
1108                         map->start      = new_map->start;
1109                         map->end        = new_map->end;
1110                         map->pgoff      = new_map->pgoff;
1111                         map->map_ip     = new_map->map_ip;
1112                         map->unmap_ip   = new_map->unmap_ip;
1113                         map__delete(new_map);
1114                         /* Ensure maps are correctly ordered */
1115                         map_groups__remove(kmaps, map);
1116                         map_groups__insert(kmaps, map);
1117                 } else {
1118                         map_groups__insert(kmaps, new_map);
1119                 }
1120         }
1121
1122         /*
1123          * Set the data type and long name so that kcore can be read via
1124          * dso__data_read_addr().
1125          */
1126         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1127                 dso->data_type = DSO_BINARY_TYPE__GUEST_KCORE;
1128         else
1129                 dso->data_type = DSO_BINARY_TYPE__KCORE;
1130         dso__set_long_name(dso, strdup(kcore_filename));
1131
1132         close(fd);
1133
1134         if (map->type == MAP__FUNCTION)
1135                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1136         else
1137                 pr_debug("Using %s for kernel data\n", kcore_filename);
1138
1139         return 0;
1140
1141 out_err:
1142         while (!list_empty(&md.maps)) {
1143                 map = list_entry(md.maps.next, struct map, node);
1144                 list_del(&map->node);
1145                 map__delete(map);
1146         }
1147         close(fd);
1148         return -EINVAL;
1149 }
1150
1151 int dso__load_kallsyms(struct dso *dso, const char *filename,
1152                        struct map *map, symbol_filter_t filter)
1153 {
1154         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1155                 return -1;
1156
1157         if (dso__load_all_kallsyms(dso, filename, map) < 0)
1158                 return -1;
1159
1160         symbols__fixup_duplicate(&dso->symbols[map->type]);
1161         symbols__fixup_end(&dso->symbols[map->type]);
1162
1163         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1164                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1165         else
1166                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1167
1168         if (!dso__load_kcore(dso, map, filename))
1169                 return dso__split_kallsyms_for_kcore(dso, map, filter);
1170         else
1171                 return dso__split_kallsyms(dso, map, filter);
1172 }
1173
1174 static int dso__load_perf_map(struct dso *dso, struct map *map,
1175                               symbol_filter_t filter)
1176 {
1177         char *line = NULL;
1178         size_t n;
1179         FILE *file;
1180         int nr_syms = 0;
1181
1182         file = fopen(dso->long_name, "r");
1183         if (file == NULL)
1184                 goto out_failure;
1185
1186         while (!feof(file)) {
1187                 u64 start, size;
1188                 struct symbol *sym;
1189                 int line_len, len;
1190
1191                 line_len = getline(&line, &n, file);
1192                 if (line_len < 0)
1193                         break;
1194
1195                 if (!line)
1196                         goto out_failure;
1197
1198                 line[--line_len] = '\0'; /* \n */
1199
1200                 len = hex2u64(line, &start);
1201
1202                 len++;
1203                 if (len + 2 >= line_len)
1204                         continue;
1205
1206                 len += hex2u64(line + len, &size);
1207
1208                 len++;
1209                 if (len + 2 >= line_len)
1210                         continue;
1211
1212                 sym = symbol__new(start, size, STB_GLOBAL, line + len);
1213
1214                 if (sym == NULL)
1215                         goto out_delete_line;
1216
1217                 if (filter && filter(map, sym))
1218                         symbol__delete(sym);
1219                 else {
1220                         symbols__insert(&dso->symbols[map->type], sym);
1221                         nr_syms++;
1222                 }
1223         }
1224
1225         free(line);
1226         fclose(file);
1227
1228         return nr_syms;
1229
1230 out_delete_line:
1231         free(line);
1232 out_failure:
1233         return -1;
1234 }
1235
1236 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1237 {
1238         char *name;
1239         int ret = -1;
1240         u_int i;
1241         struct machine *machine;
1242         char *root_dir = (char *) "";
1243         int ss_pos = 0;
1244         struct symsrc ss_[2];
1245         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1246
1247         dso__set_loaded(dso, map->type);
1248
1249         if (dso->kernel == DSO_TYPE_KERNEL)
1250                 return dso__load_kernel_sym(dso, map, filter);
1251         else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1252                 return dso__load_guest_kernel_sym(dso, map, filter);
1253
1254         if (map->groups && map->groups->machine)
1255                 machine = map->groups->machine;
1256         else
1257                 machine = NULL;
1258
1259         dso->adjust_symbols = 0;
1260
1261         if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1262                 struct stat st;
1263
1264                 if (lstat(dso->name, &st) < 0)
1265                         return -1;
1266
1267                 if (st.st_uid && (st.st_uid != geteuid())) {
1268                         pr_warning("File %s not owned by current user or root, "
1269                                 "ignoring it.\n", dso->name);
1270                         return -1;
1271                 }
1272
1273                 ret = dso__load_perf_map(dso, map, filter);
1274                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1275                                              DSO_BINARY_TYPE__NOT_FOUND;
1276                 return ret;
1277         }
1278
1279         if (machine)
1280                 root_dir = machine->root_dir;
1281
1282         name = malloc(PATH_MAX);
1283         if (!name)
1284                 return -1;
1285
1286         /* Iterate over candidate debug images.
1287          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1288          * and/or opd section) for processing.
1289          */
1290         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1291                 struct symsrc *ss = &ss_[ss_pos];
1292                 bool next_slot = false;
1293
1294                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1295
1296                 if (dso__binary_type_file(dso, symtab_type,
1297                                           root_dir, name, PATH_MAX))
1298                         continue;
1299
1300                 /* Name is now the name of the next image to try */
1301                 if (symsrc__init(ss, dso, name, symtab_type) < 0)
1302                         continue;
1303
1304                 if (!syms_ss && symsrc__has_symtab(ss)) {
1305                         syms_ss = ss;
1306                         next_slot = true;
1307                 }
1308
1309                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1310                         runtime_ss = ss;
1311                         next_slot = true;
1312                 }
1313
1314                 if (next_slot) {
1315                         ss_pos++;
1316
1317                         if (syms_ss && runtime_ss)
1318                                 break;
1319                 }
1320
1321         }
1322
1323         if (!runtime_ss && !syms_ss)
1324                 goto out_free;
1325
1326         if (runtime_ss && !syms_ss) {
1327                 syms_ss = runtime_ss;
1328         }
1329
1330         /* We'll have to hope for the best */
1331         if (!runtime_ss && syms_ss)
1332                 runtime_ss = syms_ss;
1333
1334         if (syms_ss) {
1335                 int km;
1336
1337                 km = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1338                      dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
1339                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, km);
1340         } else {
1341                 ret = -1;
1342         }
1343
1344         if (ret > 0) {
1345                 int nr_plt;
1346
1347                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1348                 if (nr_plt > 0)
1349                         ret += nr_plt;
1350         }
1351
1352         for (; ss_pos > 0; ss_pos--)
1353                 symsrc__destroy(&ss_[ss_pos - 1]);
1354 out_free:
1355         free(name);
1356         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1357                 return 0;
1358         return ret;
1359 }
1360
1361 struct map *map_groups__find_by_name(struct map_groups *mg,
1362                                      enum map_type type, const char *name)
1363 {
1364         struct rb_node *nd;
1365
1366         for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
1367                 struct map *map = rb_entry(nd, struct map, rb_node);
1368
1369                 if (map->dso && strcmp(map->dso->short_name, name) == 0)
1370                         return map;
1371         }
1372
1373         return NULL;
1374 }
1375
1376 int dso__load_vmlinux(struct dso *dso, struct map *map,
1377                       const char *vmlinux, symbol_filter_t filter)
1378 {
1379         int err = -1;
1380         struct symsrc ss;
1381         char symfs_vmlinux[PATH_MAX];
1382         enum dso_binary_type symtab_type;
1383
1384         if (vmlinux[0] == '/')
1385                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1386         else
1387                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
1388                          symbol_conf.symfs, vmlinux);
1389
1390         if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1391                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1392         else
1393                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1394
1395         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1396                 return -1;
1397
1398         err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1399         symsrc__destroy(&ss);
1400
1401         if (err > 0) {
1402                 if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1403                         dso->data_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1404                 else
1405                         dso->data_type = DSO_BINARY_TYPE__VMLINUX;
1406                 dso__set_long_name(dso, (char *)vmlinux);
1407                 dso__set_loaded(dso, map->type);
1408                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
1409         }
1410
1411         return err;
1412 }
1413
1414 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1415                            symbol_filter_t filter)
1416 {
1417         int i, err = 0;
1418         char *filename;
1419
1420         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1421                  vmlinux_path__nr_entries + 1);
1422
1423         filename = dso__build_id_filename(dso, NULL, 0);
1424         if (filename != NULL) {
1425                 err = dso__load_vmlinux(dso, map, filename, filter);
1426                 if (err > 0) {
1427                         dso->lname_alloc = 1;
1428                         goto out;
1429                 }
1430                 free(filename);
1431         }
1432
1433         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1434                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], filter);
1435                 if (err > 0) {
1436                         dso__set_long_name(dso, strdup(vmlinux_path[i]));
1437                         dso->lname_alloc = 1;
1438                         break;
1439                 }
1440         }
1441 out:
1442         return err;
1443 }
1444
1445 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1446 {
1447         char kallsyms_filename[PATH_MAX];
1448         struct dirent *dent;
1449         int ret = -1;
1450         DIR *d;
1451
1452         d = opendir(dir);
1453         if (!d)
1454                 return -1;
1455
1456         while (1) {
1457                 dent = readdir(d);
1458                 if (!dent)
1459                         break;
1460                 if (dent->d_type != DT_DIR)
1461                         continue;
1462                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1463                           "%s/%s/kallsyms", dir, dent->d_name);
1464                 if (!validate_kcore_modules(kallsyms_filename, map)) {
1465                         strlcpy(dir, kallsyms_filename, dir_sz);
1466                         ret = 0;
1467                         break;
1468                 }
1469         }
1470
1471         closedir(d);
1472
1473         return ret;
1474 }
1475
1476 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1477 {
1478         u8 host_build_id[BUILD_ID_SIZE];
1479         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1480         bool is_host = false;
1481         char path[PATH_MAX];
1482
1483         if (!dso->has_build_id) {
1484                 /*
1485                  * Last resort, if we don't have a build-id and couldn't find
1486                  * any vmlinux file, try the running kernel kallsyms table.
1487                  */
1488                 goto proc_kallsyms;
1489         }
1490
1491         if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1492                                  sizeof(host_build_id)) == 0)
1493                 is_host = dso__build_id_equal(dso, host_build_id);
1494
1495         build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1496
1497         /* Use /proc/kallsyms if possible */
1498         if (is_host) {
1499                 DIR *d;
1500                 int fd;
1501
1502                 /* If no cached kcore go with /proc/kallsyms */
1503                 scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s",
1504                           buildid_dir, sbuild_id);
1505                 d = opendir(path);
1506                 if (!d)
1507                         goto proc_kallsyms;
1508                 closedir(d);
1509
1510                 /*
1511                  * Do not check the build-id cache, until we know we cannot use
1512                  * /proc/kcore.
1513                  */
1514                 fd = open("/proc/kcore", O_RDONLY);
1515                 if (fd != -1) {
1516                         close(fd);
1517                         /* If module maps match go with /proc/kallsyms */
1518                         if (!validate_kcore_modules("/proc/kallsyms", map))
1519                                 goto proc_kallsyms;
1520                 }
1521
1522                 /* Find kallsyms in build-id cache with kcore */
1523                 if (!find_matching_kcore(map, path, sizeof(path)))
1524                         return strdup(path);
1525
1526                 goto proc_kallsyms;
1527         }
1528
1529         scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
1530                   buildid_dir, sbuild_id);
1531
1532         if (access(path, F_OK)) {
1533                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1534                        sbuild_id);
1535                 return NULL;
1536         }
1537
1538         return strdup(path);
1539
1540 proc_kallsyms:
1541         return strdup("/proc/kallsyms");
1542 }
1543
1544 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1545                                 symbol_filter_t filter)
1546 {
1547         int err;
1548         const char *kallsyms_filename = NULL;
1549         char *kallsyms_allocated_filename = NULL;
1550         /*
1551          * Step 1: if the user specified a kallsyms or vmlinux filename, use
1552          * it and only it, reporting errors to the user if it cannot be used.
1553          *
1554          * For instance, try to analyse an ARM perf.data file _without_ a
1555          * build-id, or if the user specifies the wrong path to the right
1556          * vmlinux file, obviously we can't fallback to another vmlinux (a
1557          * x86_86 one, on the machine where analysis is being performed, say),
1558          * or worse, /proc/kallsyms.
1559          *
1560          * If the specified file _has_ a build-id and there is a build-id
1561          * section in the perf.data file, we will still do the expected
1562          * validation in dso__load_vmlinux and will bail out if they don't
1563          * match.
1564          */
1565         if (symbol_conf.kallsyms_name != NULL) {
1566                 kallsyms_filename = symbol_conf.kallsyms_name;
1567                 goto do_kallsyms;
1568         }
1569
1570         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1571                 err = dso__load_vmlinux(dso, map,
1572                                         symbol_conf.vmlinux_name, filter);
1573                 if (err > 0) {
1574                         dso__set_long_name(dso,
1575                                            strdup(symbol_conf.vmlinux_name));
1576                         dso->lname_alloc = 1;
1577                         return err;
1578                 }
1579                 return err;
1580         }
1581
1582         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1583                 err = dso__load_vmlinux_path(dso, map, filter);
1584                 if (err > 0)
1585                         return err;
1586         }
1587
1588         /* do not try local files if a symfs was given */
1589         if (symbol_conf.symfs[0] != 0)
1590                 return -1;
1591
1592         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1593         if (!kallsyms_allocated_filename)
1594                 return -1;
1595
1596         kallsyms_filename = kallsyms_allocated_filename;
1597
1598 do_kallsyms:
1599         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1600         if (err > 0)
1601                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1602         free(kallsyms_allocated_filename);
1603
1604         if (err > 0 && !dso__is_kcore(dso)) {
1605                 dso__set_long_name(dso, strdup("[kernel.kallsyms]"));
1606                 map__fixup_start(map);
1607                 map__fixup_end(map);
1608         }
1609
1610         return err;
1611 }
1612
1613 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1614                                       symbol_filter_t filter)
1615 {
1616         int err;
1617         const char *kallsyms_filename = NULL;
1618         struct machine *machine;
1619         char path[PATH_MAX];
1620
1621         if (!map->groups) {
1622                 pr_debug("Guest kernel map hasn't the point to groups\n");
1623                 return -1;
1624         }
1625         machine = map->groups->machine;
1626
1627         if (machine__is_default_guest(machine)) {
1628                 /*
1629                  * if the user specified a vmlinux filename, use it and only
1630                  * it, reporting errors to the user if it cannot be used.
1631                  * Or use file guest_kallsyms inputted by user on commandline
1632                  */
1633                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
1634                         err = dso__load_vmlinux(dso, map,
1635                                 symbol_conf.default_guest_vmlinux_name, filter);
1636                         return err;
1637                 }
1638
1639                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
1640                 if (!kallsyms_filename)
1641                         return -1;
1642         } else {
1643                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1644                 kallsyms_filename = path;
1645         }
1646
1647         err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1648         if (err > 0)
1649                 pr_debug("Using %s for symbols\n", kallsyms_filename);
1650         if (err > 0 && !dso__is_kcore(dso)) {
1651                 machine__mmap_name(machine, path, sizeof(path));
1652                 dso__set_long_name(dso, strdup(path));
1653                 map__fixup_start(map);
1654                 map__fixup_end(map);
1655         }
1656
1657         return err;
1658 }
1659
1660 static void vmlinux_path__exit(void)
1661 {
1662         while (--vmlinux_path__nr_entries >= 0) {
1663                 free(vmlinux_path[vmlinux_path__nr_entries]);
1664                 vmlinux_path[vmlinux_path__nr_entries] = NULL;
1665         }
1666
1667         free(vmlinux_path);
1668         vmlinux_path = NULL;
1669 }
1670
1671 static int vmlinux_path__init(void)
1672 {
1673         struct utsname uts;
1674         char bf[PATH_MAX];
1675
1676         vmlinux_path = malloc(sizeof(char *) * 5);
1677         if (vmlinux_path == NULL)
1678                 return -1;
1679
1680         vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
1681         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1682                 goto out_fail;
1683         ++vmlinux_path__nr_entries;
1684         vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
1685         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1686                 goto out_fail;
1687         ++vmlinux_path__nr_entries;
1688
1689         /* only try running kernel version if no symfs was given */
1690         if (symbol_conf.symfs[0] != 0)
1691                 return 0;
1692
1693         if (uname(&uts) < 0)
1694                 return -1;
1695
1696         snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
1697         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1698         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1699                 goto out_fail;
1700         ++vmlinux_path__nr_entries;
1701         snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
1702         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1703         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1704                 goto out_fail;
1705         ++vmlinux_path__nr_entries;
1706         snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
1707                  uts.release);
1708         vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
1709         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1710                 goto out_fail;
1711         ++vmlinux_path__nr_entries;
1712
1713         return 0;
1714
1715 out_fail:
1716         vmlinux_path__exit();
1717         return -1;
1718 }
1719
1720 static int setup_list(struct strlist **list, const char *list_str,
1721                       const char *list_name)
1722 {
1723         if (list_str == NULL)
1724                 return 0;
1725
1726         *list = strlist__new(true, list_str);
1727         if (!*list) {
1728                 pr_err("problems parsing %s list\n", list_name);
1729                 return -1;
1730         }
1731         return 0;
1732 }
1733
1734 static bool symbol__read_kptr_restrict(void)
1735 {
1736         bool value = false;
1737
1738         if (geteuid() != 0) {
1739                 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1740                 if (fp != NULL) {
1741                         char line[8];
1742
1743                         if (fgets(line, sizeof(line), fp) != NULL)
1744                                 value = atoi(line) != 0;
1745
1746                         fclose(fp);
1747                 }
1748         }
1749
1750         return value;
1751 }
1752
1753 int symbol__init(void)
1754 {
1755         const char *symfs;
1756
1757         if (symbol_conf.initialized)
1758                 return 0;
1759
1760         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1761
1762         symbol__elf_init();
1763
1764         if (symbol_conf.sort_by_name)
1765                 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1766                                           sizeof(struct symbol));
1767
1768         if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1769                 return -1;
1770
1771         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1772                 pr_err("'.' is the only non valid --field-separator argument\n");
1773                 return -1;
1774         }
1775
1776         if (setup_list(&symbol_conf.dso_list,
1777                        symbol_conf.dso_list_str, "dso") < 0)
1778                 return -1;
1779
1780         if (setup_list(&symbol_conf.comm_list,
1781                        symbol_conf.comm_list_str, "comm") < 0)
1782                 goto out_free_dso_list;
1783
1784         if (setup_list(&symbol_conf.sym_list,
1785                        symbol_conf.sym_list_str, "symbol") < 0)
1786                 goto out_free_comm_list;
1787
1788         /*
1789          * A path to symbols of "/" is identical to ""
1790          * reset here for simplicity.
1791          */
1792         symfs = realpath(symbol_conf.symfs, NULL);
1793         if (symfs == NULL)
1794                 symfs = symbol_conf.symfs;
1795         if (strcmp(symfs, "/") == 0)
1796                 symbol_conf.symfs = "";
1797         if (symfs != symbol_conf.symfs)
1798                 free((void *)symfs);
1799
1800         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
1801
1802         symbol_conf.initialized = true;
1803         return 0;
1804
1805 out_free_comm_list:
1806         strlist__delete(symbol_conf.comm_list);
1807 out_free_dso_list:
1808         strlist__delete(symbol_conf.dso_list);
1809         return -1;
1810 }
1811
1812 void symbol__exit(void)
1813 {
1814         if (!symbol_conf.initialized)
1815                 return;
1816         strlist__delete(symbol_conf.sym_list);
1817         strlist__delete(symbol_conf.dso_list);
1818         strlist__delete(symbol_conf.comm_list);
1819         vmlinux_path__exit();
1820         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
1821         symbol_conf.initialized = false;
1822 }