tools/perf/util/symbol.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <dirent.h>
   3 #include <errno.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <linux/capability.h>
   8 #include <linux/kernel.h>
   9 #include <linux/mman.h>
  10 #include <linux/string.h>
  11 #include <linux/time64.h>
  12 #include <sys/types.h>
  13 #include <sys/stat.h>
  14 #include <sys/param.h>
  15 #include <fcntl.h>
  16 #include <unistd.h>
  17 #include <inttypes.h>
  18 #include "annotate.h"
  19 #include "build-id.h"
  20 #include "cap.h"
  21 #include "dso.h"
  22 #include "util.h" // lsdir()
  23 #include "debug.h"
  24 #include "event.h"
  25 #include "machine.h"
  26 #include "map.h"
  27 #include "symbol.h"
  28 #include "map_symbol.h"
  29 #include "mem-events.h"
  30 #include "symsrc.h"
  31 #include "strlist.h"
  32 #include "intlist.h"
  33 #include "namespaces.h"
  34 #include "header.h"
  35 #include "path.h"
  36 #include <linux/ctype.h>
  37 #include <linux/zalloc.h>
  38
  39 #include <elf.h>
  40 #include <limits.h>
  41 #include <symbol/kallsyms.h>
  42 #include <sys/utsname.h>
  43
  44 static int dso__load_kernel_sym(struct dso *dso, struct map *map);
  45 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
  46 static bool symbol__is_idle(const char *name);
  47
  48 int vmlinux_path__nr_entries;
  49 char **vmlinux_path;
  50
  51 struct symbol_conf symbol_conf = {
  52         .nanosecs               = false,
  53         .use_modules            = true,
  54         .try_vmlinux_path       = true,
  55         .demangle               = true,
  56         .demangle_kernel        = false,
  57         .cumulate_callchain     = true,
  58         .time_quantum           = 100 * NSEC_PER_MSEC, /* 100ms */
  59         .show_hist_headers      = true,
  60         .symfs                  = "",
  61         .event_group            = true,
  62         .inline_name            = true,
  63         .res_sample             = 0,
  64 };
  65
  66 struct map_list_node {
  67         struct list_head node;
  68         struct map *map;
  69 };
  70
  71 static struct map_list_node *map_list_node__new(void)
  72 {
  73         return malloc(sizeof(struct map_list_node));
  74 }
  75
  76 static enum dso_binary_type binary_type_symtab[] = {
  77         DSO_BINARY_TYPE__KALLSYMS,
  78         DSO_BINARY_TYPE__GUEST_KALLSYMS,
  79         DSO_BINARY_TYPE__JAVA_JIT,
  80         DSO_BINARY_TYPE__DEBUGLINK,
  81         DSO_BINARY_TYPE__BUILD_ID_CACHE,
  82         DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
  83         DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
  84         DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
  85         DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
  86         DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
  87         DSO_BINARY_TYPE__GUEST_KMODULE,
  88         DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
  89         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
  90         DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
  91         DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
  92         DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
  93         DSO_BINARY_TYPE__NOT_FOUND,
  94 };
  95
  96 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
  97
  98 static bool symbol_type__filter(char symbol_type)
  99 {
 100         symbol_type = toupper(symbol_type);
 101         return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B';
 102 }
 103
 104 static int prefix_underscores_count(const char *str)
 105 {
 106         const char *tail = str;
 107
 108         while (*tail == '_')
 109                 tail++;
 110
 111         return tail - str;
 112 }
 113
 114 const char * __weak arch__normalize_symbol_name(const char *name)
 115 {
 116         return name;
 117 }
 118
 119 int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
 120 {
 121         return strcmp(namea, nameb);
 122 }
 123
 124 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
 125                                         unsigned int n)
 126 {
 127         return strncmp(namea, nameb, n);
 128 }
 129
 130 int __weak arch__choose_best_symbol(struct symbol *syma,
 131                                     struct symbol *symb __maybe_unused)
 132 {
 133         /* Avoid "SyS" kernel syscall aliases */
 134         if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
 135                 return SYMBOL_B;
 136         if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
 137                 return SYMBOL_B;
 138
 139         return SYMBOL_A;
 140 }
 141
 142 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
 143 {
 144         s64 a;
 145         s64 b;
 146         size_t na, nb;
 147
 148         /* Prefer a symbol with non zero length */
 149         a = syma->end - syma->start;
 150         b = symb->end - symb->start;
 151         if ((b == 0) && (a > 0))
 152                 return SYMBOL_A;
 153         else if ((a == 0) && (b > 0))
 154                 return SYMBOL_B;
 155
 156         /* Prefer a non weak symbol over a weak one */
 157         a = syma->binding == STB_WEAK;
 158         b = symb->binding == STB_WEAK;
 159         if (b && !a)
 160                 return SYMBOL_A;
 161         if (a && !b)
 162                 return SYMBOL_B;
 163
 164         /* Prefer a global symbol over a non global one */
 165         a = syma->binding == STB_GLOBAL;
 166         b = symb->binding == STB_GLOBAL;
 167         if (a && !b)
 168                 return SYMBOL_A;
 169         if (b && !a)
 170                 return SYMBOL_B;
 171
 172         /* Prefer a symbol with less underscores */
 173         a = prefix_underscores_count(syma->name);
 174         b = prefix_underscores_count(symb->name);
 175         if (b > a)
 176                 return SYMBOL_A;
 177         else if (a > b)
 178                 return SYMBOL_B;
 179
 180         /* Choose the symbol with the longest name */
 181         na = strlen(syma->name);
 182         nb = strlen(symb->name);
 183         if (na > nb)
 184                 return SYMBOL_A;
 185         else if (na < nb)
 186                 return SYMBOL_B;
 187
 188         return arch__choose_best_symbol(syma, symb);
 189 }
 190
 191 void symbols__fixup_duplicate(struct rb_root_cached *symbols)
 192 {
 193         struct rb_node *nd;
 194         struct symbol *curr, *next;
 195
 196         if (symbol_conf.allow_aliases)
 197                 return;
 198
 199         nd = rb_first_cached(symbols);
 200
 201         while (nd) {
 202                 curr = rb_entry(nd, struct symbol, rb_node);
 203 again:
 204                 nd = rb_next(&curr->rb_node);
 205                 if (!nd)
 206                         break;
 207
 208                 next = rb_entry(nd, struct symbol, rb_node);
 209                 if (curr->start != next->start)
 210                         continue;
 211
 212                 if (choose_best_symbol(curr, next) == SYMBOL_A) {
 213                         if (next->type == STT_GNU_IFUNC)
 214                                 curr->ifunc_alias = true;
 215                         rb_erase_cached(&next->rb_node, symbols);
 216                         symbol__delete(next);
 217                         goto again;
 218                 } else {
 219                         if (curr->type == STT_GNU_IFUNC)
 220                                 next->ifunc_alias = true;
 221                         nd = rb_next(&curr->rb_node);
 222                         rb_erase_cached(&curr->rb_node, symbols);
 223                         symbol__delete(curr);
 224                 }
 225         }
 226 }
 227
 228 /* Update zero-sized symbols using the address of the next symbol */
 229 void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
 230 {
 231         struct rb_node *nd, *prevnd = rb_first_cached(symbols);
 232         struct symbol *curr, *prev;
 233
 234         if (prevnd == NULL)
 235                 return;
 236
 237         curr = rb_entry(prevnd, struct symbol, rb_node);
 238
 239         for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
 240                 prev = curr;
 241                 curr = rb_entry(nd, struct symbol, rb_node);
 242
 243                 /*
 244                  * On some architecture kernel text segment start is located at
 245                  * some low memory address, while modules are located at high
 246                  * memory addresses (or vice versa).  The gap between end of
 247                  * kernel text segment and beginning of first module's text
 248                  * segment is very big.  Therefore do not fill this gap and do
 249                  * not assign it to the kernel dso map (kallsyms).
 250                  *
 251                  * Also BPF code can be allocated separately from text segments
 252                  * and modules.  So the last entry in a module should not fill
 253                  * the gap too.
 254                  *
 255                  * In kallsyms, it determines module symbols using '[' character
 256                  * like in:
 257                  *   ffffffffc1937000 T hdmi_driver_init  [snd_hda_codec_hdmi]
 258                  */
 259                 if (prev->end == prev->start) {
 260                         const char *prev_mod;
 261                         const char *curr_mod;
 262
 263                         if (!is_kallsyms) {
 264                                 prev->end = curr->start;
 265                                 continue;
 266                         }
 267
 268                         prev_mod = strchr(prev->name, '[');
 269                         curr_mod = strchr(curr->name, '[');
 270
 271                         /* Last kernel/module symbol mapped to end of page */
 272                         if (!prev_mod != !curr_mod)
 273                                 prev->end = roundup(prev->end + 4096, 4096);
 274                         /* Last symbol in the previous module */
 275                         else if (prev_mod && strcmp(prev_mod, curr_mod))
 276                                 prev->end = roundup(prev->end + 4096, 4096);
 277                         else
 278                                 prev->end = curr->start;
 279
 280                         pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
 281                                   __func__, prev->name, prev->end);
 282                 }
 283         }
 284
 285         /* Last entry */
 286         if (curr->end == curr->start)
 287                 curr->end = roundup(curr->start, 4096) + 4096;
 288 }
 289
 290 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
 291 {
 292         size_t namelen = strlen(name) + 1;
 293         struct symbol *sym = calloc(1, (symbol_conf.priv_size +
 294                                         sizeof(*sym) + namelen));
 295         if (sym == NULL)
 296                 return NULL;
 297
 298         if (symbol_conf.priv_size) {
 299                 if (symbol_conf.init_annotation) {
 300                         struct annotation *notes = (void *)sym;
 301                         annotation__init(notes);
 302                 }
 303                 sym = ((void *)sym) + symbol_conf.priv_size;
 304         }
 305
 306         sym->start   = start;
 307         sym->end     = len ? start + len : start;
 308         sym->type    = type;
 309         sym->binding = binding;
 310         sym->namelen = namelen - 1;
 311
 312         pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
 313                   __func__, name, start, sym->end);
 314         memcpy(sym->name, name, namelen);
 315
 316         return sym;
 317 }
 318
 319 void symbol__delete(struct symbol *sym)
 320 {
 321         if (symbol_conf.priv_size) {
 322                 if (symbol_conf.init_annotation) {
 323                         struct annotation *notes = symbol__annotation(sym);
 324
 325                         annotation__exit(notes);
 326                 }
 327         }
 328         free(((void *)sym) - symbol_conf.priv_size);
 329 }
 330
 331 void symbols__delete(struct rb_root_cached *symbols)
 332 {
 333         struct symbol *pos;
 334         struct rb_node *next = rb_first_cached(symbols);
 335
 336         while (next) {
 337                 pos = rb_entry(next, struct symbol, rb_node);
 338                 next = rb_next(&pos->rb_node);
 339                 rb_erase_cached(&pos->rb_node, symbols);
 340                 symbol__delete(pos);
 341         }
 342 }
 343
 344 void __symbols__insert(struct rb_root_cached *symbols,
 345                        struct symbol *sym, bool kernel)
 346 {
 347         struct rb_node **p = &symbols->rb_root.rb_node;
 348         struct rb_node *parent = NULL;
 349         const u64 ip = sym->start;
 350         struct symbol *s;
 351         bool leftmost = true;
 352
 353         if (kernel) {
 354                 const char *name = sym->name;
 355                 /*
 356                  * ppc64 uses function descriptors and appends a '.' to the
 357                  * start of every instruction address. Remove it.
 358                  */
 359                 if (name[0] == '.')
 360                         name++;
 361                 sym->idle = symbol__is_idle(name);
 362         }
 363
 364         while (*p != NULL) {
 365                 parent = *p;
 366                 s = rb_entry(parent, struct symbol, rb_node);
 367                 if (ip < s->start)
 368                         p = &(*p)->rb_left;
 369                 else {
 370                         p = &(*p)->rb_right;
 371                         leftmost = false;
 372                 }
 373         }
 374         rb_link_node(&sym->rb_node, parent, p);
 375         rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
 376 }
 377
 378 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
 379 {
 380         __symbols__insert(symbols, sym, false);
 381 }
 382
 383 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
 384 {
 385         struct rb_node *n;
 386
 387         if (symbols == NULL)
 388                 return NULL;
 389
 390         n = symbols->rb_root.rb_node;
 391
 392         while (n) {
 393                 struct symbol *s = rb_entry(n, struct symbol, rb_node);
 394
 395                 if (ip < s->start)
 396                         n = n->rb_left;
 397                 else if (ip > s->end || (ip == s->end && ip != s->start))
 398                         n = n->rb_right;
 399                 else
 400                         return s;
 401         }
 402
 403         return NULL;
 404 }
 405
 406 static struct symbol *symbols__first(struct rb_root_cached *symbols)
 407 {
 408         struct rb_node *n = rb_first_cached(symbols);
 409
 410         if (n)
 411                 return rb_entry(n, struct symbol, rb_node);
 412
 413         return NULL;
 414 }
 415
 416 static struct symbol *symbols__last(struct rb_root_cached *symbols)
 417 {
 418         struct rb_node *n = rb_last(&symbols->rb_root);
 419
 420         if (n)
 421                 return rb_entry(n, struct symbol, rb_node);
 422
 423         return NULL;
 424 }
 425
 426 static struct symbol *symbols__next(struct symbol *sym)
 427 {
 428         struct rb_node *n = rb_next(&sym->rb_node);
 429
 430         if (n)
 431                 return rb_entry(n, struct symbol, rb_node);
 432
 433         return NULL;
 434 }
 435
 436 static int symbols__sort_name_cmp(const void *vlhs, const void *vrhs)
 437 {
 438         const struct symbol *lhs = *((const struct symbol **)vlhs);
 439         const struct symbol *rhs = *((const struct symbol **)vrhs);
 440
 441         return strcmp(lhs->name, rhs->name);
 442 }
 443
 444 static struct symbol **symbols__sort_by_name(struct rb_root_cached *source, size_t *len)
 445 {
 446         struct rb_node *nd;
 447         struct symbol **result;
 448         size_t i = 0, size = 0;
 449
 450         for (nd = rb_first_cached(source); nd; nd = rb_next(nd))
 451                 size++;
 452
 453         result = malloc(sizeof(*result) * size);
 454         if (!result)
 455                 return NULL;
 456
 457         for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
 458                 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
 459
 460                 result[i++] = pos;
 461         }
 462         qsort(result, size, sizeof(*result), symbols__sort_name_cmp);
 463         *len = size;
 464         return result;
 465 }
 466
 467 int symbol__match_symbol_name(const char *name, const char *str,
 468                               enum symbol_tag_include includes)
 469 {
 470         const char *versioning;
 471
 472         if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
 473             (versioning = strstr(name, "@@"))) {
 474                 int len = strlen(str);
 475
 476                 if (len < versioning - name)
 477                         len = versioning - name;
 478
 479                 return arch__compare_symbol_names_n(name, str, len);
 480         } else
 481                 return arch__compare_symbol_names(name, str);
 482 }
 483
 484 static struct symbol *symbols__find_by_name(struct symbol *symbols[],
 485                                             size_t symbols_len,
 486                                             const char *name,
 487                                             enum symbol_tag_include includes,
 488                                             size_t *found_idx)
 489 {
 490         size_t i, lower = 0, upper = symbols_len;
 491         struct symbol *s = NULL;
 492
 493         if (found_idx)
 494                 *found_idx = SIZE_MAX;
 495
 496         if (!symbols_len)
 497                 return NULL;
 498
 499         while (lower < upper) {
 500                 int cmp;
 501
 502                 i = (lower + upper) / 2;
 503                 cmp = symbol__match_symbol_name(symbols[i]->name, name, includes);
 504
 505                 if (cmp > 0)
 506                         upper = i;
 507                 else if (cmp < 0)
 508                         lower = i + 1;
 509                 else {
 510                         if (found_idx)
 511                                 *found_idx = i;
 512                         s = symbols[i];
 513                         break;
 514                 }
 515         }
 516         if (s && includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) {
 517                 /* return first symbol that has same name (if any) */
 518                 for (; i > 0; i--) {
 519                         struct symbol *tmp = symbols[i - 1];
 520
 521                         if (!arch__compare_symbol_names(tmp->name, s->name)) {
 522                                 if (found_idx)
 523                                         *found_idx = i - 1;
 524                                 s = tmp;
 525                         } else
 526                                 break;
 527                 }
 528         }
 529         assert(!found_idx || !s || s == symbols[*found_idx]);
 530         return s;
 531 }
 532
 533 void dso__reset_find_symbol_cache(struct dso *dso)
 534 {
 535         dso->last_find_result.addr   = 0;
 536         dso->last_find_result.symbol = NULL;
 537 }
 538
 539 void dso__insert_symbol(struct dso *dso, struct symbol *sym)
 540 {
 541         __symbols__insert(&dso->symbols, sym, dso->kernel);
 542
 543         /* update the symbol cache if necessary */
 544         if (dso->last_find_result.addr >= sym->start &&
 545             (dso->last_find_result.addr < sym->end ||
 546             sym->start == sym->end)) {
 547                 dso->last_find_result.symbol = sym;
 548         }
 549 }
 550
 551 void dso__delete_symbol(struct dso *dso, struct symbol *sym)
 552 {
 553         rb_erase_cached(&sym->rb_node, &dso->symbols);
 554         symbol__delete(sym);
 555         dso__reset_find_symbol_cache(dso);
 556 }
 557
 558 struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
 559 {
 560         if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
 561                 dso->last_find_result.addr   = addr;
 562                 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
 563         }
 564
 565         return dso->last_find_result.symbol;
 566 }
 567
 568 struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr)
 569 {
 570         return symbols__find(&dso->symbols, addr);
 571 }
 572
 573 struct symbol *dso__first_symbol(struct dso *dso)
 574 {
 575         return symbols__first(&dso->symbols);
 576 }
 577
 578 struct symbol *dso__last_symbol(struct dso *dso)
 579 {
 580         return symbols__last(&dso->symbols);
 581 }
 582
 583 struct symbol *dso__next_symbol(struct symbol *sym)
 584 {
 585         return symbols__next(sym);
 586 }
 587
 588 struct symbol *dso__next_symbol_by_name(struct dso *dso, size_t *idx)
 589 {
 590         if (*idx + 1 >= dso->symbol_names_len)
 591                 return NULL;
 592
 593         ++*idx;
 594         return dso->symbol_names[*idx];
 595 }
 596
 597  /*
 598   * Returns first symbol that matched with @name.
 599   */
 600 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx)
 601 {
 602         struct symbol *s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len,
 603                                                 name, SYMBOL_TAG_INCLUDE__NONE, idx);
 604         if (!s)
 605                 s = symbols__find_by_name(dso->symbol_names, dso->symbol_names_len,
 606                                         name, SYMBOL_TAG_INCLUDE__DEFAULT_ONLY, idx);
 607         return s;
 608 }
 609
 610 void dso__sort_by_name(struct dso *dso)
 611 {
 612         mutex_lock(&dso->lock);
 613         if (!dso__sorted_by_name(dso)) {
 614                 size_t len;
 615
 616                 dso->symbol_names = symbols__sort_by_name(&dso->symbols, &len);
 617                 if (dso->symbol_names) {
 618                         dso->symbol_names_len = len;
 619                         dso__set_sorted_by_name(dso);
 620                 }
 621         }
 622         mutex_unlock(&dso->lock);
 623 }
 624
 625 /*
 626  * While we find nice hex chars, build a long_val.
 627  * Return number of chars processed.
 628  */
 629 static int hex2u64(const char *ptr, u64 *long_val)
 630 {
 631         char *p;
 632
 633         *long_val = strtoull(ptr, &p, 16);
 634
 635         return p - ptr;
 636 }
 637
 638
 639 int modules__parse(const char *filename, void *arg,
 640                    int (*process_module)(void *arg, const char *name,
 641                                          u64 start, u64 size))
 642 {
 643         char *line = NULL;
 644         size_t n;
 645         FILE *file;
 646         int err = 0;
 647
 648         file = fopen(filename, "r");
 649         if (file == NULL)
 650                 return -1;
 651
 652         while (1) {
 653                 char name[PATH_MAX];
 654                 u64 start, size;
 655                 char *sep, *endptr;
 656                 ssize_t line_len;
 657
 658                 line_len = getline(&line, &n, file);
 659                 if (line_len < 0) {
 660                         if (feof(file))
 661                                 break;
 662                         err = -1;
 663                         goto out;
 664                 }
 665
 666                 if (!line) {
 667                         err = -1;
 668                         goto out;
 669                 }
 670
 671                 line[--line_len] = '\0'; /* \n */
 672
 673                 sep = strrchr(line, 'x');
 674                 if (sep == NULL)
 675                         continue;
 676
 677                 hex2u64(sep + 1, &start);
 678
 679                 sep = strchr(line, ' ');
 680                 if (sep == NULL)
 681                         continue;
 682
 683                 *sep = '\0';
 684
 685                 scnprintf(name, sizeof(name), "[%s]", line);
 686
 687                 size = strtoul(sep + 1, &endptr, 0);
 688                 if (*endptr != ' ' && *endptr != '\t')
 689                         continue;
 690
 691                 err = process_module(arg, name, start, size);
 692                 if (err)
 693                         break;
 694         }
 695 out:
 696         free(line);
 697         fclose(file);
 698         return err;
 699 }
 700
 701 /*
 702  * These are symbols in the kernel image, so make sure that
 703  * sym is from a kernel DSO.
 704  */
 705 static bool symbol__is_idle(const char *name)
 706 {
 707         const char * const idle_symbols[] = {
 708                 "acpi_idle_do_entry",
 709                 "acpi_processor_ffh_cstate_enter",
 710                 "arch_cpu_idle",
 711                 "cpu_idle",
 712                 "cpu_startup_entry",
 713                 "idle_cpu",
 714                 "intel_idle",
 715                 "intel_idle_ibrs",
 716                 "default_idle",
 717                 "native_safe_halt",
 718                 "enter_idle",
 719                 "exit_idle",
 720                 "mwait_idle",
 721                 "mwait_idle_with_hints",
 722                 "mwait_idle_with_hints.constprop.0",
 723                 "poll_idle",
 724                 "ppc64_runlatch_off",
 725                 "pseries_dedicated_idle_sleep",
 726                 "psw_idle",
 727                 "psw_idle_exit",
 728                 NULL
 729         };
 730         int i;
 731         static struct strlist *idle_symbols_list;
 732
 733         if (idle_symbols_list)
 734                 return strlist__has_entry(idle_symbols_list, name);
 735
 736         idle_symbols_list = strlist__new(NULL, NULL);
 737
 738         for (i = 0; idle_symbols[i]; i++)
 739                 strlist__add(idle_symbols_list, idle_symbols[i]);
 740
 741         return strlist__has_entry(idle_symbols_list, name);
 742 }
 743
 744 static int map__process_kallsym_symbol(void *arg, const char *name,
 745                                        char type, u64 start)
 746 {
 747         struct symbol *sym;
 748         struct dso *dso = arg;
 749         struct rb_root_cached *root = &dso->symbols;
 750
 751         if (!symbol_type__filter(type))
 752                 return 0;
 753
 754         /* Ignore local symbols for ARM modules */
 755         if (name[0] == '$')
 756                 return 0;
 757
 758         /*
 759          * module symbols are not sorted so we add all
 760          * symbols, setting length to 0, and rely on
 761          * symbols__fixup_end() to fix it up.
 762          */
 763         sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
 764         if (sym == NULL)
 765                 return -ENOMEM;
 766         /*
 767          * We will pass the symbols to the filter later, in
 768          * map__split_kallsyms, when we have split the maps per module
 769          */
 770         __symbols__insert(root, sym, !strchr(name, '['));
 771
 772         return 0;
 773 }
 774
 775 /*
 776  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 777  * so that we can in the next step set the symbol ->end address and then
 778  * call kernel_maps__split_kallsyms.
 779  */
 780 static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
 781 {
 782         return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
 783 }
 784
 785 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
 786 {
 787         struct symbol *pos;
 788         int count = 0;
 789         struct rb_root_cached old_root = dso->symbols;
 790         struct rb_root_cached *root = &dso->symbols;
 791         struct rb_node *next = rb_first_cached(root);
 792
 793         if (!kmaps)
 794                 return -1;
 795
 796         *root = RB_ROOT_CACHED;
 797
 798         while (next) {
 799                 struct map *curr_map;
 800                 struct dso *curr_map_dso;
 801                 char *module;
 802
 803                 pos = rb_entry(next, struct symbol, rb_node);
 804                 next = rb_next(&pos->rb_node);
 805
 806                 rb_erase_cached(&pos->rb_node, &old_root);
 807                 RB_CLEAR_NODE(&pos->rb_node);
 808                 module = strchr(pos->name, '\t');
 809                 if (module)
 810                         *module = '\0';
 811
 812                 curr_map = maps__find(kmaps, pos->start);
 813
 814                 if (!curr_map) {
 815                         symbol__delete(pos);
 816                         continue;
 817                 }
 818                 curr_map_dso = map__dso(curr_map);
 819                 pos->start -= map__start(curr_map) - map__pgoff(curr_map);
 820                 if (pos->end > map__end(curr_map))
 821                         pos->end = map__end(curr_map);
 822                 if (pos->end)
 823                         pos->end -= map__start(curr_map) - map__pgoff(curr_map);
 824                 symbols__insert(&curr_map_dso->symbols, pos);
 825                 ++count;
 826                 map__put(curr_map);
 827         }
 828
 829         /* Symbols have been adjusted */
 830         dso->adjust_symbols = 1;
 831
 832         return count;
 833 }
 834
 835 /*
 836  * Split the symbols into maps, making sure there are no overlaps, i.e. the
 837  * kernel range is broken in several maps, named [kernel].N, as we don't have
 838  * the original ELF section names vmlinux have.
 839  */
 840 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
 841                                 struct map *initial_map)
 842 {
 843         struct machine *machine;
 844         struct map *curr_map = map__get(initial_map);
 845         struct symbol *pos;
 846         int count = 0, moved = 0;
 847         struct rb_root_cached *root = &dso->symbols;
 848         struct rb_node *next = rb_first_cached(root);
 849         int kernel_range = 0;
 850         bool x86_64;
 851
 852         if (!kmaps)
 853                 return -1;
 854
 855         machine = maps__machine(kmaps);
 856
 857         x86_64 = machine__is(machine, "x86_64");
 858
 859         while (next) {
 860                 char *module;
 861
 862                 pos = rb_entry(next, struct symbol, rb_node);
 863                 next = rb_next(&pos->rb_node);
 864
 865                 module = strchr(pos->name, '\t');
 866                 if (module) {
 867                         struct dso *curr_map_dso;
 868
 869                         if (!symbol_conf.use_modules)
 870                                 goto discard_symbol;
 871
 872                         *module++ = '\0';
 873                         curr_map_dso = map__dso(curr_map);
 874                         if (strcmp(curr_map_dso->short_name, module)) {
 875                                 if (!RC_CHK_EQUAL(curr_map, initial_map) &&
 876                                     dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 877                                     machine__is_default_guest(machine)) {
 878                                         /*
 879                                          * We assume all symbols of a module are
 880                                          * continuous in * kallsyms, so curr_map
 881                                          * points to a module and all its
 882                                          * symbols are in its kmap. Mark it as
 883                                          * loaded.
 884                                          */
 885                                         dso__set_loaded(curr_map_dso);
 886                                 }
 887
 888                                 map__zput(curr_map);
 889                                 curr_map = maps__find_by_name(kmaps, module);
 890                                 if (curr_map == NULL) {
 891                                         pr_debug("%s/proc/{kallsyms,modules} "
 892                                                  "inconsistency while looking "
 893                                                  "for \"%s\" module!\n",
 894                                                  machine->root_dir, module);
 895                                         curr_map = map__get(initial_map);
 896                                         goto discard_symbol;
 897                                 }
 898                                 curr_map_dso = map__dso(curr_map);
 899                                 if (curr_map_dso->loaded &&
 900                                     !machine__is_default_guest(machine))
 901                                         goto discard_symbol;
 902                         }
 903                         /*
 904                          * So that we look just like we get from .ko files,
 905                          * i.e. not prelinked, relative to initial_map->start.
 906                          */
 907                         pos->start = map__map_ip(curr_map, pos->start);
 908                         pos->end   = map__map_ip(curr_map, pos->end);
 909                 } else if (x86_64 && is_entry_trampoline(pos->name)) {
 910                         /*
 911                          * These symbols are not needed anymore since the
 912                          * trampoline maps refer to the text section and it's
 913                          * symbols instead. Avoid having to deal with
 914                          * relocations, and the assumption that the first symbol
 915                          * is the start of kernel text, by simply removing the
 916                          * symbols at this point.
 917                          */
 918                         goto discard_symbol;
 919                 } else if (!RC_CHK_EQUAL(curr_map, initial_map)) {
 920                         char dso_name[PATH_MAX];
 921                         struct dso *ndso;
 922
 923                         if (delta) {
 924                                 /* Kernel was relocated at boot time */
 925                                 pos->start -= delta;
 926                                 pos->end -= delta;
 927                         }
 928
 929                         if (count == 0) {
 930                                 map__zput(curr_map);
 931                                 curr_map = map__get(initial_map);
 932                                 goto add_symbol;
 933                         }
 934
 935                         if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
 936                                 snprintf(dso_name, sizeof(dso_name),
 937                                         "[guest.kernel].%d",
 938                                         kernel_range++);
 939                         else
 940                                 snprintf(dso_name, sizeof(dso_name),
 941                                         "[kernel].%d",
 942                                         kernel_range++);
 943
 944                         ndso = dso__new(dso_name);
 945                         map__zput(curr_map);
 946                         if (ndso == NULL)
 947                                 return -1;
 948
 949                         ndso->kernel = dso->kernel;
 950
 951                         curr_map = map__new2(pos->start, ndso);
 952                         if (curr_map == NULL) {
 953                                 dso__put(ndso);
 954                                 return -1;
 955                         }
 956
 957                         map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY);
 958                         if (maps__insert(kmaps, curr_map)) {
 959                                 map__zput(curr_map);
 960                                 dso__put(ndso);
 961                                 return -1;
 962                         }
 963                         ++kernel_range;
 964                 } else if (delta) {
 965                         /* Kernel was relocated at boot time */
 966                         pos->start -= delta;
 967                         pos->end -= delta;
 968                 }
 969 add_symbol:
 970                 if (!RC_CHK_EQUAL(curr_map, initial_map)) {
 971                         struct dso *curr_map_dso = map__dso(curr_map);
 972
 973                         rb_erase_cached(&pos->rb_node, root);
 974                         symbols__insert(&curr_map_dso->symbols, pos);
 975                         ++moved;
 976                 } else
 977                         ++count;
 978
 979                 continue;
 980 discard_symbol:
 981                 rb_erase_cached(&pos->rb_node, root);
 982                 symbol__delete(pos);
 983         }
 984
 985         if (!RC_CHK_EQUAL(curr_map, initial_map) &&
 986             dso->kernel == DSO_SPACE__KERNEL_GUEST &&
 987             machine__is_default_guest(maps__machine(kmaps))) {
 988                 dso__set_loaded(map__dso(curr_map));
 989         }
 990         map__put(curr_map);
 991         return count + moved;
 992 }
 993
 994 bool symbol__restricted_filename(const char *filename,
 995                                  const char *restricted_filename)
 996 {
 997         bool restricted = false;
 998
 999         if (symbol_conf.kptr_restrict) {
1000                 char *r = realpath(filename, NULL);
1001
1002                 if (r != NULL) {
1003                         restricted = strcmp(r, restricted_filename) == 0;
1004                         free(r);
1005                         return restricted;
1006                 }
1007         }
1008
1009         return restricted;
1010 }
1011
1012 struct module_info {
1013         struct rb_node rb_node;
1014         char *name;
1015         u64 start;
1016 };
1017
1018 static void add_module(struct module_info *mi, struct rb_root *modules)
1019 {
1020         struct rb_node **p = &modules->rb_node;
1021         struct rb_node *parent = NULL;
1022         struct module_info *m;
1023
1024         while (*p != NULL) {
1025                 parent = *p;
1026                 m = rb_entry(parent, struct module_info, rb_node);
1027                 if (strcmp(mi->name, m->name) < 0)
1028                         p = &(*p)->rb_left;
1029                 else
1030                         p = &(*p)->rb_right;
1031         }
1032         rb_link_node(&mi->rb_node, parent, p);
1033         rb_insert_color(&mi->rb_node, modules);
1034 }
1035
1036 static void delete_modules(struct rb_root *modules)
1037 {
1038         struct module_info *mi;
1039         struct rb_node *next = rb_first(modules);
1040
1041         while (next) {
1042                 mi = rb_entry(next, struct module_info, rb_node);
1043                 next = rb_next(&mi->rb_node);
1044                 rb_erase(&mi->rb_node, modules);
1045                 zfree(&mi->name);
1046                 free(mi);
1047         }
1048 }
1049
1050 static struct module_info *find_module(const char *name,
1051                                        struct rb_root *modules)
1052 {
1053         struct rb_node *n = modules->rb_node;
1054
1055         while (n) {
1056                 struct module_info *m;
1057                 int cmp;
1058
1059                 m = rb_entry(n, struct module_info, rb_node);
1060                 cmp = strcmp(name, m->name);
1061                 if (cmp < 0)
1062                         n = n->rb_left;
1063                 else if (cmp > 0)
1064                         n = n->rb_right;
1065                 else
1066                         return m;
1067         }
1068
1069         return NULL;
1070 }
1071
1072 static int __read_proc_modules(void *arg, const char *name, u64 start,
1073                                u64 size __maybe_unused)
1074 {
1075         struct rb_root *modules = arg;
1076         struct module_info *mi;
1077
1078         mi = zalloc(sizeof(struct module_info));
1079         if (!mi)
1080                 return -ENOMEM;
1081
1082         mi->name = strdup(name);
1083         mi->start = start;
1084
1085         if (!mi->name) {
1086                 free(mi);
1087                 return -ENOMEM;
1088         }
1089
1090         add_module(mi, modules);
1091
1092         return 0;
1093 }
1094
1095 static int read_proc_modules(const char *filename, struct rb_root *modules)
1096 {
1097         if (symbol__restricted_filename(filename, "/proc/modules"))
1098                 return -1;
1099
1100         if (modules__parse(filename, modules, __read_proc_modules)) {
1101                 delete_modules(modules);
1102                 return -1;
1103         }
1104
1105         return 0;
1106 }
1107
1108 int compare_proc_modules(const char *from, const char *to)
1109 {
1110         struct rb_root from_modules = RB_ROOT;
1111         struct rb_root to_modules = RB_ROOT;
1112         struct rb_node *from_node, *to_node;
1113         struct module_info *from_m, *to_m;
1114         int ret = -1;
1115
1116         if (read_proc_modules(from, &from_modules))
1117                 return -1;
1118
1119         if (read_proc_modules(to, &to_modules))
1120                 goto out_delete_from;
1121
1122         from_node = rb_first(&from_modules);
1123         to_node = rb_first(&to_modules);
1124         while (from_node) {
1125                 if (!to_node)
1126                         break;
1127
1128                 from_m = rb_entry(from_node, struct module_info, rb_node);
1129                 to_m = rb_entry(to_node, struct module_info, rb_node);
1130
1131                 if (from_m->start != to_m->start ||
1132                     strcmp(from_m->name, to_m->name))
1133                         break;
1134
1135                 from_node = rb_next(from_node);
1136                 to_node = rb_next(to_node);
1137         }
1138
1139         if (!from_node && !to_node)
1140                 ret = 0;
1141
1142         delete_modules(&to_modules);
1143 out_delete_from:
1144         delete_modules(&from_modules);
1145
1146         return ret;
1147 }
1148
1149 static int do_validate_kcore_modules_cb(struct map *old_map, void *data)
1150 {
1151         struct rb_root *modules = data;
1152         struct module_info *mi;
1153         struct dso *dso;
1154
1155         if (!__map__is_kmodule(old_map))
1156                 return 0;
1157
1158         dso = map__dso(old_map);
1159         /* Module must be in memory at the same address */
1160         mi = find_module(dso->short_name, modules);
1161         if (!mi || mi->start != map__start(old_map))
1162                 return -EINVAL;
1163
1164         return 0;
1165 }
1166
1167 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1168 {
1169         struct rb_root modules = RB_ROOT;
1170         int err;
1171
1172         err = read_proc_modules(filename, &modules);
1173         if (err)
1174                 return err;
1175
1176         err = maps__for_each_map(kmaps, do_validate_kcore_modules_cb, &modules);
1177
1178         delete_modules(&modules);
1179         return err;
1180 }
1181
1182 /*
1183  * If kallsyms is referenced by name then we look for filename in the same
1184  * directory.
1185  */
1186 static bool filename_from_kallsyms_filename(char *filename,
1187                                             const char *base_name,
1188                                             const char *kallsyms_filename)
1189 {
1190         char *name;
1191
1192         strcpy(filename, kallsyms_filename);
1193         name = strrchr(filename, '/');
1194         if (!name)
1195                 return false;
1196
1197         name += 1;
1198
1199         if (!strcmp(name, "kallsyms")) {
1200                 strcpy(name, base_name);
1201                 return true;
1202         }
1203
1204         return false;
1205 }
1206
1207 static int validate_kcore_modules(const char *kallsyms_filename,
1208                                   struct map *map)
1209 {
1210         struct maps *kmaps = map__kmaps(map);
1211         char modules_filename[PATH_MAX];
1212
1213         if (!kmaps)
1214                 return -EINVAL;
1215
1216         if (!filename_from_kallsyms_filename(modules_filename, "modules",
1217                                              kallsyms_filename))
1218                 return -EINVAL;
1219
1220         if (do_validate_kcore_modules(modules_filename, kmaps))
1221                 return -EINVAL;
1222
1223         return 0;
1224 }
1225
1226 static int validate_kcore_addresses(const char *kallsyms_filename,
1227                                     struct map *map)
1228 {
1229         struct kmap *kmap = map__kmap(map);
1230
1231         if (!kmap)
1232                 return -EINVAL;
1233
1234         if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1235                 u64 start;
1236
1237                 if (kallsyms__get_function_start(kallsyms_filename,
1238                                                  kmap->ref_reloc_sym->name, &start))
1239                         return -ENOENT;
1240                 if (start != kmap->ref_reloc_sym->addr)
1241                         return -EINVAL;
1242         }
1243
1244         return validate_kcore_modules(kallsyms_filename, map);
1245 }
1246
1247 struct kcore_mapfn_data {
1248         struct dso *dso;
1249         struct list_head maps;
1250 };
1251
1252 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1253 {
1254         struct kcore_mapfn_data *md = data;
1255         struct map_list_node *list_node = map_list_node__new();
1256
1257         if (!list_node)
1258                 return -ENOMEM;
1259
1260         list_node->map = map__new2(start, md->dso);
1261         if (!list_node->map) {
1262                 free(list_node);
1263                 return -ENOMEM;
1264         }
1265
1266         map__set_end(list_node->map, map__start(list_node->map) + len);
1267         map__set_pgoff(list_node->map, pgoff);
1268
1269         list_add(&list_node->node, &md->maps);
1270
1271         return 0;
1272 }
1273
1274 static bool remove_old_maps(struct map *map, void *data)
1275 {
1276         const struct map *map_to_save = data;
1277
1278         /*
1279          * We need to preserve eBPF maps even if they are covered by kcore,
1280          * because we need to access eBPF dso for source data.
1281          */
1282         return !RC_CHK_EQUAL(map, map_to_save) && !__map__is_bpf_prog(map);
1283 }
1284
1285 static int dso__load_kcore(struct dso *dso, struct map *map,
1286                            const char *kallsyms_filename)
1287 {
1288         struct maps *kmaps = map__kmaps(map);
1289         struct kcore_mapfn_data md;
1290         struct map *replacement_map = NULL;
1291         struct machine *machine;
1292         bool is_64_bit;
1293         int err, fd;
1294         char kcore_filename[PATH_MAX];
1295         u64 stext;
1296
1297         if (!kmaps)
1298                 return -EINVAL;
1299
1300         machine = maps__machine(kmaps);
1301
1302         /* This function requires that the map is the kernel map */
1303         if (!__map__is_kernel(map))
1304                 return -EINVAL;
1305
1306         if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1307                                              kallsyms_filename))
1308                 return -EINVAL;
1309
1310         /* Modules and kernel must be present at their original addresses */
1311         if (validate_kcore_addresses(kallsyms_filename, map))
1312                 return -EINVAL;
1313
1314         md.dso = dso;
1315         INIT_LIST_HEAD(&md.maps);
1316
1317         fd = open(kcore_filename, O_RDONLY);
1318         if (fd < 0) {
1319                 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1320                          kcore_filename);
1321                 return -EINVAL;
1322         }
1323
1324         /* Read new maps into temporary lists */
1325         err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md,
1326                               &is_64_bit);
1327         if (err)
1328                 goto out_err;
1329         dso->is_64_bit = is_64_bit;
1330
1331         if (list_empty(&md.maps)) {
1332                 err = -EINVAL;
1333                 goto out_err;
1334         }
1335
1336         /* Remove old maps */
1337         maps__remove_maps(kmaps, remove_old_maps, map);
1338         machine->trampolines_mapped = false;
1339
1340         /* Find the kernel map using the '_stext' symbol */
1341         if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1342                 u64 replacement_size = 0;
1343                 struct map_list_node *new_node;
1344
1345                 list_for_each_entry(new_node, &md.maps, node) {
1346                         struct map *new_map = new_node->map;
1347                         u64 new_size = map__size(new_map);
1348
1349                         if (!(stext >= map__start(new_map) && stext < map__end(new_map)))
1350                                 continue;
1351
1352                         /*
1353                          * On some architectures, ARM64 for example, the kernel
1354                          * text can get allocated inside of the vmalloc segment.
1355                          * Select the smallest matching segment, in case stext
1356                          * falls within more than one in the list.
1357                          */
1358                         if (!replacement_map || new_size < replacement_size) {
1359                                 replacement_map = new_map;
1360                                 replacement_size = new_size;
1361                         }
1362                 }
1363         }
1364
1365         if (!replacement_map)
1366                 replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map;
1367
1368         /* Add new maps */
1369         while (!list_empty(&md.maps)) {
1370                 struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node);
1371                 struct map *new_map = new_node->map;
1372
1373                 list_del_init(&new_node->node);
1374
1375                 if (RC_CHK_EQUAL(new_map, replacement_map)) {
1376                         struct map *map_ref;
1377
1378                         map__set_start(map, map__start(new_map));
1379                         map__set_end(map, map__end(new_map));
1380                         map__set_pgoff(map, map__pgoff(new_map));
1381                         map__set_mapping_type(map, map__mapping_type(new_map));
1382                         /* Ensure maps are correctly ordered */
1383                         map_ref = map__get(map);
1384                         maps__remove(kmaps, map_ref);
1385                         err = maps__insert(kmaps, map_ref);
1386                         map__put(map_ref);
1387                         map__put(new_map);
1388                         if (err)
1389                                 goto out_err;
1390                 } else {
1391                         /*
1392                          * Merge kcore map into existing maps,
1393                          * and ensure that current maps (eBPF)
1394                          * stay intact.
1395                          */
1396                         if (maps__merge_in(kmaps, new_map)) {
1397                                 err = -EINVAL;
1398                                 goto out_err;
1399                         }
1400                 }
1401                 free(new_node);
1402         }
1403
1404         if (machine__is(machine, "x86_64")) {
1405                 u64 addr;
1406
1407                 /*
1408                  * If one of the corresponding symbols is there, assume the
1409                  * entry trampoline maps are too.
1410                  */
1411                 if (!kallsyms__get_function_start(kallsyms_filename,
1412                                                   ENTRY_TRAMPOLINE_NAME,
1413                                                   &addr))
1414                         machine->trampolines_mapped = true;
1415         }
1416
1417         /*
1418          * Set the data type and long name so that kcore can be read via
1419          * dso__data_read_addr().
1420          */
1421         if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1422                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1423         else
1424                 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1425         dso__set_long_name(dso, strdup(kcore_filename), true);
1426
1427         close(fd);
1428
1429         if (map__prot(map) & PROT_EXEC)
1430                 pr_debug("Using %s for kernel object code\n", kcore_filename);
1431         else
1432                 pr_debug("Using %s for kernel data\n", kcore_filename);
1433
1434         return 0;
1435
1436 out_err:
1437         while (!list_empty(&md.maps)) {
1438                 struct map_list_node *list_node;
1439
1440                 list_node = list_entry(md.maps.next, struct map_list_node, node);
1441                 list_del_init(&list_node->node);
1442                 map__zput(list_node->map);
1443                 free(list_node);
1444         }
1445         close(fd);
1446         return err;
1447 }
1448
1449 /*
1450  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1451  * delta based on the relocation reference symbol.
1452  */
1453 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1454 {
1455         u64 addr;
1456
1457         if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1458                 return 0;
1459
1460         if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1461                 return -1;
1462
1463         *delta = addr - kmap->ref_reloc_sym->addr;
1464         return 0;
1465 }
1466
1467 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1468                          struct map *map, bool no_kcore)
1469 {
1470         struct kmap *kmap = map__kmap(map);
1471         u64 delta = 0;
1472
1473         if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1474                 return -1;
1475
1476         if (!kmap || !kmap->kmaps)
1477                 return -1;
1478
1479         if (dso__load_all_kallsyms(dso, filename) < 0)
1480                 return -1;
1481
1482         if (kallsyms__delta(kmap, filename, &delta))
1483                 return -1;
1484
1485         symbols__fixup_end(&dso->symbols, true);
1486         symbols__fixup_duplicate(&dso->symbols);
1487
1488         if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1489                 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1490         else
1491                 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1492
1493         if (!no_kcore && !dso__load_kcore(dso, map, filename))
1494                 return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1495         else
1496                 return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1497 }
1498
1499 int dso__load_kallsyms(struct dso *dso, const char *filename,
1500                        struct map *map)
1501 {
1502         return __dso__load_kallsyms(dso, filename, map, false);
1503 }
1504
1505 static int dso__load_perf_map(const char *map_path, struct dso *dso)
1506 {
1507         char *line = NULL;
1508         size_t n;
1509         FILE *file;
1510         int nr_syms = 0;
1511
1512         file = fopen(map_path, "r");
1513         if (file == NULL)
1514                 goto out_failure;
1515
1516         while (!feof(file)) {
1517                 u64 start, size;
1518                 struct symbol *sym;
1519                 int line_len, len;
1520
1521                 line_len = getline(&line, &n, file);
1522                 if (line_len < 0)
1523                         break;
1524
1525                 if (!line)
1526                         goto out_failure;
1527
1528                 line[--line_len] = '\0'; /* \n */
1529
1530                 len = hex2u64(line, &start);
1531
1532                 len++;
1533                 if (len + 2 >= line_len)
1534                         continue;
1535
1536                 len += hex2u64(line + len, &size);
1537
1538                 len++;
1539                 if (len + 2 >= line_len)
1540                         continue;
1541
1542                 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1543
1544                 if (sym == NULL)
1545                         goto out_delete_line;
1546
1547                 symbols__insert(&dso->symbols, sym);
1548                 nr_syms++;
1549         }
1550
1551         free(line);
1552         fclose(file);
1553
1554         return nr_syms;
1555
1556 out_delete_line:
1557         free(line);
1558 out_failure:
1559         return -1;
1560 }
1561
1562 #ifdef HAVE_LIBBFD_SUPPORT
1563 #define PACKAGE 'perf'
1564 #include <bfd.h>
1565
1566 static int bfd_symbols__cmpvalue(const void *a, const void *b)
1567 {
1568         const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1569
1570         if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1571                 return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1572
1573         return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1574 }
1575
1576 static int bfd2elf_binding(asymbol *symbol)
1577 {
1578         if (symbol->flags & BSF_WEAK)
1579                 return STB_WEAK;
1580         if (symbol->flags & BSF_GLOBAL)
1581                 return STB_GLOBAL;
1582         if (symbol->flags & BSF_LOCAL)
1583                 return STB_LOCAL;
1584         return -1;
1585 }
1586
1587 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1588 {
1589         int err = -1;
1590         long symbols_size, symbols_count, i;
1591         asection *section;
1592         asymbol **symbols, *sym;
1593         struct symbol *symbol;
1594         bfd *abfd;
1595         u64 start, len;
1596
1597         abfd = bfd_openr(debugfile, NULL);
1598         if (!abfd)
1599                 return -1;
1600
1601         if (!bfd_check_format(abfd, bfd_object)) {
1602                 pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1603                           dso->long_name);
1604                 goto out_close;
1605         }
1606
1607         if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1608                 goto out_close;
1609
1610         symbols_size = bfd_get_symtab_upper_bound(abfd);
1611         if (symbols_size == 0) {
1612                 bfd_close(abfd);
1613                 return 0;
1614         }
1615
1616         if (symbols_size < 0)
1617                 goto out_close;
1618
1619         symbols = malloc(symbols_size);
1620         if (!symbols)
1621                 goto out_close;
1622
1623         symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1624         if (symbols_count < 0)
1625                 goto out_free;
1626
1627         section = bfd_get_section_by_name(abfd, ".text");
1628         if (section) {
1629                 for (i = 0; i < symbols_count; ++i) {
1630                         if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
1631                             !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
1632                                 break;
1633                 }
1634                 if (i < symbols_count) {
1635                         /* PE symbols can only have 4 bytes, so use .text high bits */
1636                         dso->text_offset = section->vma - (u32)section->vma;
1637                         dso->text_offset += (u32)bfd_asymbol_value(symbols[i]);
1638                         dso->text_end = (section->vma - dso->text_offset) + section->size;
1639                 } else {
1640                         dso->text_offset = section->vma - section->filepos;
1641                         dso->text_end = section->filepos + section->size;
1642                 }
1643         }
1644
1645         qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1646
1647 #ifdef bfd_get_section
1648 #define bfd_asymbol_section bfd_get_section
1649 #endif
1650         for (i = 0; i < symbols_count; ++i) {
1651                 sym = symbols[i];
1652                 section = bfd_asymbol_section(sym);
1653                 if (bfd2elf_binding(sym) < 0)
1654                         continue;
1655
1656                 while (i + 1 < symbols_count &&
1657                        bfd_asymbol_section(symbols[i + 1]) == section &&
1658                        bfd2elf_binding(symbols[i + 1]) < 0)
1659                         i++;
1660
1661                 if (i + 1 < symbols_count &&
1662                     bfd_asymbol_section(symbols[i + 1]) == section)
1663                         len = symbols[i + 1]->value - sym->value;
1664                 else
1665                         len = section->size - sym->value;
1666
1667                 start = bfd_asymbol_value(sym) - dso->text_offset;
1668                 symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1669                                      bfd_asymbol_name(sym));
1670                 if (!symbol)
1671                         goto out_free;
1672
1673                 symbols__insert(&dso->symbols, symbol);
1674         }
1675 #ifdef bfd_get_section
1676 #undef bfd_asymbol_section
1677 #endif
1678
1679         symbols__fixup_end(&dso->symbols, false);
1680         symbols__fixup_duplicate(&dso->symbols);
1681         dso->adjust_symbols = 1;
1682
1683         err = 0;
1684 out_free:
1685         free(symbols);
1686 out_close:
1687         bfd_close(abfd);
1688         return err;
1689 }
1690 #endif
1691
1692 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1693                                            enum dso_binary_type type)
1694 {
1695         switch (type) {
1696         case DSO_BINARY_TYPE__JAVA_JIT:
1697         case DSO_BINARY_TYPE__DEBUGLINK:
1698         case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1699         case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1700         case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1701         case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1702         case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1703         case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1704                 return !kmod && dso->kernel == DSO_SPACE__USER;
1705
1706         case DSO_BINARY_TYPE__KALLSYMS:
1707         case DSO_BINARY_TYPE__VMLINUX:
1708         case DSO_BINARY_TYPE__KCORE:
1709                 return dso->kernel == DSO_SPACE__KERNEL;
1710
1711         case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1712         case DSO_BINARY_TYPE__GUEST_VMLINUX:
1713         case DSO_BINARY_TYPE__GUEST_KCORE:
1714                 return dso->kernel == DSO_SPACE__KERNEL_GUEST;
1715
1716         case DSO_BINARY_TYPE__GUEST_KMODULE:
1717         case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1718         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1719         case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1720                 /*
1721                  * kernel modules know their symtab type - it's set when
1722                  * creating a module dso in machine__addnew_module_map().
1723                  */
1724                 return kmod && dso->symtab_type == type;
1725
1726         case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1727         case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1728                 return true;
1729
1730         case DSO_BINARY_TYPE__BPF_PROG_INFO:
1731         case DSO_BINARY_TYPE__BPF_IMAGE:
1732         case DSO_BINARY_TYPE__OOL:
1733         case DSO_BINARY_TYPE__NOT_FOUND:
1734         default:
1735                 return false;
1736         }
1737 }
1738
1739 /* Checks for the existence of the perf-<pid>.map file in two different
1740  * locations.  First, if the process is a separate mount namespace, check in
1741  * that namespace using the pid of the innermost pid namespace.  If's not in a
1742  * namespace, or the file can't be found there, try in the mount namespace of
1743  * the tracing process using our view of its pid.
1744  */
1745 static int dso__find_perf_map(char *filebuf, size_t bufsz,
1746                               struct nsinfo **nsip)
1747 {
1748         struct nscookie nsc;
1749         struct nsinfo *nsi;
1750         struct nsinfo *nnsi;
1751         int rc = -1;
1752
1753         nsi = *nsip;
1754
1755         if (nsinfo__need_setns(nsi)) {
1756                 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
1757                 nsinfo__mountns_enter(nsi, &nsc);
1758                 rc = access(filebuf, R_OK);
1759                 nsinfo__mountns_exit(&nsc);
1760                 if (rc == 0)
1761                         return rc;
1762         }
1763
1764         nnsi = nsinfo__copy(nsi);
1765         if (nnsi) {
1766                 nsinfo__put(nsi);
1767
1768                 nsinfo__clear_need_setns(nnsi);
1769                 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
1770                 *nsip = nnsi;
1771                 rc = 0;
1772         }
1773
1774         return rc;
1775 }
1776
1777 int dso__load(struct dso *dso, struct map *map)
1778 {
1779         char *name;
1780         int ret = -1;
1781         u_int i;
1782         struct machine *machine = NULL;
1783         char *root_dir = (char *) "";
1784         int ss_pos = 0;
1785         struct symsrc ss_[2];
1786         struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1787         bool kmod;
1788         bool perfmap;
1789         struct build_id bid;
1790         struct nscookie nsc;
1791         char newmapname[PATH_MAX];
1792         const char *map_path = dso->long_name;
1793
1794         mutex_lock(&dso->lock);
1795         perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
1796         if (perfmap) {
1797                 if (dso->nsinfo && (dso__find_perf_map(newmapname,
1798                     sizeof(newmapname), &dso->nsinfo) == 0)) {
1799                         map_path = newmapname;
1800                 }
1801         }
1802
1803         nsinfo__mountns_enter(dso->nsinfo, &nsc);
1804
1805         /* check again under the dso->lock */
1806         if (dso__loaded(dso)) {
1807                 ret = 1;
1808                 goto out;
1809         }
1810
1811         kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1812                 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1813                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1814                 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1815
1816         if (dso->kernel && !kmod) {
1817                 if (dso->kernel == DSO_SPACE__KERNEL)
1818                         ret = dso__load_kernel_sym(dso, map);
1819                 else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1820                         ret = dso__load_guest_kernel_sym(dso, map);
1821
1822                 machine = maps__machine(map__kmaps(map));
1823                 if (machine__is(machine, "x86_64"))
1824                         machine__map_x86_64_entry_trampolines(machine, dso);
1825                 goto out;
1826         }
1827
1828         dso->adjust_symbols = 0;
1829
1830         if (perfmap) {
1831                 ret = dso__load_perf_map(map_path, dso);
1832                 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1833                                              DSO_BINARY_TYPE__NOT_FOUND;
1834                 goto out;
1835         }
1836
1837         if (machine)
1838                 root_dir = machine->root_dir;
1839
1840         name = malloc(PATH_MAX);
1841         if (!name)
1842                 goto out;
1843
1844         /*
1845          * Read the build id if possible. This is required for
1846          * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1847          */
1848         if (!dso->has_build_id &&
1849             is_regular_file(dso->long_name)) {
1850             __symbol__join_symfs(name, PATH_MAX, dso->long_name);
1851                 if (filename__read_build_id(name, &bid) > 0)
1852                         dso__set_build_id(dso, &bid);
1853         }
1854
1855         /*
1856          * Iterate over candidate debug images.
1857          * Keep track of "interesting" ones (those which have a symtab, dynsym,
1858          * and/or opd section) for processing.
1859          */
1860         for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1861                 struct symsrc *ss = &ss_[ss_pos];
1862                 bool next_slot = false;
1863                 bool is_reg;
1864                 bool nsexit;
1865                 int bfdrc = -1;
1866                 int sirc = -1;
1867
1868                 enum dso_binary_type symtab_type = binary_type_symtab[i];
1869
1870                 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1871                     symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1872
1873                 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1874                         continue;
1875
1876                 if (dso__read_binary_type_filename(dso, symtab_type,
1877                                                    root_dir, name, PATH_MAX))
1878                         continue;
1879
1880                 if (nsexit)
1881                         nsinfo__mountns_exit(&nsc);
1882
1883                 is_reg = is_regular_file(name);
1884                 if (!is_reg && errno == ENOENT && dso->nsinfo) {
1885                         char *new_name = dso__filename_with_chroot(dso, name);
1886                         if (new_name) {
1887                                 is_reg = is_regular_file(new_name);
1888                                 strlcpy(name, new_name, PATH_MAX);
1889                                 free(new_name);
1890                         }
1891                 }
1892
1893 #ifdef HAVE_LIBBFD_SUPPORT
1894                 if (is_reg)
1895                         bfdrc = dso__load_bfd_symbols(dso, name);
1896 #endif
1897                 if (is_reg && bfdrc < 0)
1898                         sirc = symsrc__init(ss, dso, name, symtab_type);
1899
1900                 if (nsexit)
1901                         nsinfo__mountns_enter(dso->nsinfo, &nsc);
1902
1903                 if (bfdrc == 0) {
1904                         ret = 0;
1905                         break;
1906                 }
1907
1908                 if (!is_reg || sirc < 0)
1909                         continue;
1910
1911                 if (!syms_ss && symsrc__has_symtab(ss)) {
1912                         syms_ss = ss;
1913                         next_slot = true;
1914                         if (!dso->symsrc_filename)
1915                                 dso->symsrc_filename = strdup(name);
1916                 }
1917
1918                 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1919                         runtime_ss = ss;
1920                         next_slot = true;
1921                 }
1922
1923                 if (next_slot) {
1924                         ss_pos++;
1925
1926                         if (syms_ss && runtime_ss)
1927                                 break;
1928                 } else {
1929                         symsrc__destroy(ss);
1930                 }
1931
1932         }
1933
1934         if (!runtime_ss && !syms_ss)
1935                 goto out_free;
1936
1937         if (runtime_ss && !syms_ss) {
1938                 syms_ss = runtime_ss;
1939         }
1940
1941         /* We'll have to hope for the best */
1942         if (!runtime_ss && syms_ss)
1943                 runtime_ss = syms_ss;
1944
1945         if (syms_ss)
1946                 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1947         else
1948                 ret = -1;
1949
1950         if (ret > 0) {
1951                 int nr_plt;
1952
1953                 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
1954                 if (nr_plt > 0)
1955                         ret += nr_plt;
1956         }
1957
1958         for (; ss_pos > 0; ss_pos--)
1959                 symsrc__destroy(&ss_[ss_pos - 1]);
1960 out_free:
1961         free(name);
1962         if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1963                 ret = 0;
1964 out:
1965         dso__set_loaded(dso);
1966         mutex_unlock(&dso->lock);
1967         nsinfo__mountns_exit(&nsc);
1968
1969         return ret;
1970 }
1971
1972 int dso__load_vmlinux(struct dso *dso, struct map *map,
1973                       const char *vmlinux, bool vmlinux_allocated)
1974 {
1975         int err = -1;
1976         struct symsrc ss;
1977         char symfs_vmlinux[PATH_MAX];
1978         enum dso_binary_type symtab_type;
1979
1980         if (vmlinux[0] == '/')
1981                 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1982         else
1983                 symbol__join_symfs(symfs_vmlinux, vmlinux);
1984
1985         if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1986                 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1987         else
1988                 symtab_type = DSO_BINARY_TYPE__VMLINUX;
1989
1990         if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1991                 return -1;
1992
1993         /*
1994          * dso__load_sym() may copy 'dso' which will result in the copies having
1995          * an incorrect long name unless we set it here first.
1996          */
1997         dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1998         if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1999                 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2000         else
2001                 dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
2002
2003         err = dso__load_sym(dso, map, &ss, &ss, 0);
2004         symsrc__destroy(&ss);
2005
2006         if (err > 0) {
2007                 dso__set_loaded(dso);
2008                 pr_debug("Using %s for symbols\n", symfs_vmlinux);
2009         }
2010
2011         return err;
2012 }
2013
2014 int dso__load_vmlinux_path(struct dso *dso, struct map *map)
2015 {
2016         int i, err = 0;
2017         char *filename = NULL;
2018
2019         pr_debug("Looking at the vmlinux_path (%d entries long)\n",
2020                  vmlinux_path__nr_entries + 1);
2021
2022         for (i = 0; i < vmlinux_path__nr_entries; ++i) {
2023                 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
2024                 if (err > 0)
2025                         goto out;
2026         }
2027
2028         if (!symbol_conf.ignore_vmlinux_buildid)
2029                 filename = dso__build_id_filename(dso, NULL, 0, false);
2030         if (filename != NULL) {
2031                 err = dso__load_vmlinux(dso, map, filename, true);
2032                 if (err > 0)
2033                         goto out;
2034                 free(filename);
2035         }
2036 out:
2037         return err;
2038 }
2039
2040 static bool visible_dir_filter(const char *name, struct dirent *d)
2041 {
2042         if (d->d_type != DT_DIR)
2043                 return false;
2044         return lsdir_no_dot_filter(name, d);
2045 }
2046
2047 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2048 {
2049         char kallsyms_filename[PATH_MAX];
2050         int ret = -1;
2051         struct strlist *dirs;
2052         struct str_node *nd;
2053
2054         dirs = lsdir(dir, visible_dir_filter);
2055         if (!dirs)
2056                 return -1;
2057
2058         strlist__for_each_entry(nd, dirs) {
2059                 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2060                           "%s/%s/kallsyms", dir, nd->s);
2061                 if (!validate_kcore_addresses(kallsyms_filename, map)) {
2062                         strlcpy(dir, kallsyms_filename, dir_sz);
2063                         ret = 0;
2064                         break;
2065                 }
2066         }
2067
2068         strlist__delete(dirs);
2069
2070         return ret;
2071 }
2072
2073 /*
2074  * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2075  * since access(R_OK) only checks with real UID/GID but open() use effective
2076  * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2077  */
2078 static bool filename__readable(const char *file)
2079 {
2080         int fd = open(file, O_RDONLY);
2081         if (fd < 0)
2082                 return false;
2083         close(fd);
2084         return true;
2085 }
2086
2087 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2088 {
2089         struct build_id bid;
2090         char sbuild_id[SBUILD_ID_SIZE];
2091         bool is_host = false;
2092         char path[PATH_MAX];
2093
2094         if (!dso->has_build_id) {
2095                 /*
2096                  * Last resort, if we don't have a build-id and couldn't find
2097                  * any vmlinux file, try the running kernel kallsyms table.
2098                  */
2099                 goto proc_kallsyms;
2100         }
2101
2102         if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2103                 is_host = dso__build_id_equal(dso, &bid);
2104
2105         /* Try a fast path for /proc/kallsyms if possible */
2106         if (is_host) {
2107                 /*
2108                  * Do not check the build-id cache, unless we know we cannot use
2109                  * /proc/kcore or module maps don't match to /proc/kallsyms.
2110                  * To check readability of /proc/kcore, do not use access(R_OK)
2111                  * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2112                  * can't check it.
2113                  */
2114                 if (filename__readable("/proc/kcore") &&
2115                     !validate_kcore_addresses("/proc/kallsyms", map))
2116                         goto proc_kallsyms;
2117         }
2118
2119         build_id__sprintf(&dso->bid, sbuild_id);
2120
2121         /* Find kallsyms in build-id cache with kcore */
2122         scnprintf(path, sizeof(path), "%s/%s/%s",
2123                   buildid_dir, DSO__NAME_KCORE, sbuild_id);
2124
2125         if (!find_matching_kcore(map, path, sizeof(path)))
2126                 return strdup(path);
2127
2128         /* Use current /proc/kallsyms if possible */
2129         if (is_host) {
2130 proc_kallsyms:
2131                 return strdup("/proc/kallsyms");
2132         }
2133
2134         /* Finally, find a cache of kallsyms */
2135         if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2136                 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2137                        sbuild_id);
2138                 return NULL;
2139         }
2140
2141         return strdup(path);
2142 }
2143
2144 static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2145 {
2146         int err;
2147         const char *kallsyms_filename = NULL;
2148         char *kallsyms_allocated_filename = NULL;
2149         char *filename = NULL;
2150
2151         /*
2152          * Step 1: if the user specified a kallsyms or vmlinux filename, use
2153          * it and only it, reporting errors to the user if it cannot be used.
2154          *
2155          * For instance, try to analyse an ARM perf.data file _without_ a
2156          * build-id, or if the user specifies the wrong path to the right
2157          * vmlinux file, obviously we can't fallback to another vmlinux (a
2158          * x86_86 one, on the machine where analysis is being performed, say),
2159          * or worse, /proc/kallsyms.
2160          *
2161          * If the specified file _has_ a build-id and there is a build-id
2162          * section in the perf.data file, we will still do the expected
2163          * validation in dso__load_vmlinux and will bail out if they don't
2164          * match.
2165          */
2166         if (symbol_conf.kallsyms_name != NULL) {
2167                 kallsyms_filename = symbol_conf.kallsyms_name;
2168                 goto do_kallsyms;
2169         }
2170
2171         if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2172                 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2173         }
2174
2175         /*
2176          * Before checking on common vmlinux locations, check if it's
2177          * stored as standard build id binary (not kallsyms) under
2178          * .debug cache.
2179          */
2180         if (!symbol_conf.ignore_vmlinux_buildid)
2181                 filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2182         if (filename != NULL) {
2183                 err = dso__load_vmlinux(dso, map, filename, true);
2184                 if (err > 0)
2185                         return err;
2186                 free(filename);
2187         }
2188
2189         if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2190                 err = dso__load_vmlinux_path(dso, map);
2191                 if (err > 0)
2192                         return err;
2193         }
2194
2195         /* do not try local files if a symfs was given */
2196         if (symbol_conf.symfs[0] != 0)
2197                 return -1;
2198
2199         kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2200         if (!kallsyms_allocated_filename)
2201                 return -1;
2202
2203         kallsyms_filename = kallsyms_allocated_filename;
2204
2205 do_kallsyms:
2206         err = dso__load_kallsyms(dso, kallsyms_filename, map);
2207         if (err > 0)
2208                 pr_debug("Using %s for symbols\n", kallsyms_filename);
2209         free(kallsyms_allocated_filename);
2210
2211         if (err > 0 && !dso__is_kcore(dso)) {
2212                 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
2213                 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2214                 map__fixup_start(map);
2215                 map__fixup_end(map);
2216         }
2217
2218         return err;
2219 }
2220
2221 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2222 {
2223         int err;
2224         const char *kallsyms_filename;
2225         struct machine *machine = maps__machine(map__kmaps(map));
2226         char path[PATH_MAX];
2227
2228         if (machine->kallsyms_filename) {
2229                 kallsyms_filename = machine->kallsyms_filename;
2230         } else if (machine__is_default_guest(machine)) {
2231                 /*
2232                  * if the user specified a vmlinux filename, use it and only
2233                  * it, reporting errors to the user if it cannot be used.
2234                  * Or use file guest_kallsyms inputted by user on commandline
2235                  */
2236                 if (symbol_conf.default_guest_vmlinux_name != NULL) {
2237                         err = dso__load_vmlinux(dso, map,
2238                                                 symbol_conf.default_guest_vmlinux_name,
2239                                                 false);
2240                         return err;
2241                 }
2242
2243                 kallsyms_filename = symbol_conf.default_guest_kallsyms;
2244                 if (!kallsyms_filename)
2245                         return -1;
2246         } else {
2247                 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2248                 kallsyms_filename = path;
2249         }
2250
2251         err = dso__load_kallsyms(dso, kallsyms_filename, map);
2252         if (err > 0)
2253                 pr_debug("Using %s for symbols\n", kallsyms_filename);
2254         if (err > 0 && !dso__is_kcore(dso)) {
2255                 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
2256                 dso__set_long_name(dso, machine->mmap_name, false);
2257                 map__fixup_start(map);
2258                 map__fixup_end(map);
2259         }
2260
2261         return err;
2262 }
2263
2264 static void vmlinux_path__exit(void)
2265 {
2266         while (--vmlinux_path__nr_entries >= 0)
2267                 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2268         vmlinux_path__nr_entries = 0;
2269
2270         zfree(&vmlinux_path);
2271 }
2272
2273 static const char * const vmlinux_paths[] = {
2274         "vmlinux",
2275         "/boot/vmlinux"
2276 };
2277
2278 static const char * const vmlinux_paths_upd[] = {
2279         "/boot/vmlinux-%s",
2280         "/usr/lib/debug/boot/vmlinux-%s",
2281         "/lib/modules/%s/build/vmlinux",
2282         "/usr/lib/debug/lib/modules/%s/vmlinux",
2283         "/usr/lib/debug/boot/vmlinux-%s.debug"
2284 };
2285
2286 static int vmlinux_path__add(const char *new_entry)
2287 {
2288         vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2289         if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2290                 return -1;
2291         ++vmlinux_path__nr_entries;
2292
2293         return 0;
2294 }
2295
2296 static int vmlinux_path__init(struct perf_env *env)
2297 {
2298         struct utsname uts;
2299         char bf[PATH_MAX];
2300         char *kernel_version;
2301         unsigned int i;
2302
2303         vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2304                               ARRAY_SIZE(vmlinux_paths_upd)));
2305         if (vmlinux_path == NULL)
2306                 return -1;
2307
2308         for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2309                 if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2310                         goto out_fail;
2311
2312         /* only try kernel version if no symfs was given */
2313         if (symbol_conf.symfs[0] != 0)
2314                 return 0;
2315
2316         if (env) {
2317                 kernel_version = env->os_release;
2318         } else {
2319                 if (uname(&uts) < 0)
2320                         goto out_fail;
2321
2322                 kernel_version = uts.release;
2323         }
2324
2325         for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2326                 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2327                 if (vmlinux_path__add(bf) < 0)
2328                         goto out_fail;
2329         }
2330
2331         return 0;
2332
2333 out_fail:
2334         vmlinux_path__exit();
2335         return -1;
2336 }
2337
2338 int setup_list(struct strlist **list, const char *list_str,
2339                       const char *list_name)
2340 {
2341         if (list_str == NULL)
2342                 return 0;
2343
2344         *list = strlist__new(list_str, NULL);
2345         if (!*list) {
2346                 pr_err("problems parsing %s list\n", list_name);
2347                 return -1;
2348         }
2349
2350         symbol_conf.has_filter = true;
2351         return 0;
2352 }
2353
2354 int setup_intlist(struct intlist **list, const char *list_str,
2355                   const char *list_name)
2356 {
2357         if (list_str == NULL)
2358                 return 0;
2359
2360         *list = intlist__new(list_str);
2361         if (!*list) {
2362                 pr_err("problems parsing %s list\n", list_name);
2363                 return -1;
2364         }
2365         return 0;
2366 }
2367
2368 static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
2369 {
2370         struct str_node *pos, *tmp;
2371         unsigned long val;
2372         char *sep;
2373         const char *end;
2374         int i = 0, err;
2375
2376         *addr_list = intlist__new(NULL);
2377         if (!*addr_list)
2378                 return -1;
2379
2380         strlist__for_each_entry_safe(pos, tmp, sym_list) {
2381                 errno = 0;
2382                 val = strtoul(pos->s, &sep, 16);
2383                 if (errno || (sep == pos->s))
2384                         continue;
2385
2386                 if (*sep != '\0') {
2387                         end = pos->s + strlen(pos->s) - 1;
2388                         while (end >= sep && isspace(*end))
2389                                 end--;
2390
2391                         if (end >= sep)
2392                                 continue;
2393                 }
2394
2395                 err = intlist__add(*addr_list, val);
2396                 if (err)
2397                         break;
2398
2399                 strlist__remove(sym_list, pos);
2400                 i++;
2401         }
2402
2403         if (i == 0) {
2404                 intlist__delete(*addr_list);
2405                 *addr_list = NULL;
2406         }
2407
2408         return 0;
2409 }
2410
2411 static bool symbol__read_kptr_restrict(void)
2412 {
2413         bool value = false;
2414         FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2415
2416         if (fp != NULL) {
2417                 char line[8];
2418
2419                 if (fgets(line, sizeof(line), fp) != NULL)
2420                         value = perf_cap__capable(CAP_SYSLOG) ?
2421                                         (atoi(line) >= 2) :
2422                                         (atoi(line) != 0);
2423
2424                 fclose(fp);
2425         }
2426
2427         /* Per kernel/kallsyms.c:
2428          * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2429          */
2430         if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
2431                 value = true;
2432
2433         return value;
2434 }
2435
2436 int symbol__annotation_init(void)
2437 {
2438         if (symbol_conf.init_annotation)
2439                 return 0;
2440
2441         if (symbol_conf.initialized) {
2442                 pr_err("Annotation needs to be init before symbol__init()\n");
2443                 return -1;
2444         }
2445
2446         symbol_conf.priv_size += sizeof(struct annotation);
2447         symbol_conf.init_annotation = true;
2448         return 0;
2449 }
2450
2451 int symbol__init(struct perf_env *env)
2452 {
2453         const char *symfs;
2454
2455         if (symbol_conf.initialized)
2456                 return 0;
2457
2458         symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2459
2460         symbol__elf_init();
2461
2462         if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2463                 return -1;
2464
2465         if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2466                 pr_err("'.' is the only non valid --field-separator argument\n");
2467                 return -1;
2468         }
2469
2470         if (setup_list(&symbol_conf.dso_list,
2471                        symbol_conf.dso_list_str, "dso") < 0)
2472                 return -1;
2473
2474         if (setup_list(&symbol_conf.comm_list,
2475                        symbol_conf.comm_list_str, "comm") < 0)
2476                 goto out_free_dso_list;
2477
2478         if (setup_intlist(&symbol_conf.pid_list,
2479                        symbol_conf.pid_list_str, "pid") < 0)
2480                 goto out_free_comm_list;
2481
2482         if (setup_intlist(&symbol_conf.tid_list,
2483                        symbol_conf.tid_list_str, "tid") < 0)
2484                 goto out_free_pid_list;
2485
2486         if (setup_list(&symbol_conf.sym_list,
2487                        symbol_conf.sym_list_str, "symbol") < 0)
2488                 goto out_free_tid_list;
2489
2490         if (symbol_conf.sym_list &&
2491             setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
2492                 goto out_free_sym_list;
2493
2494         if (setup_list(&symbol_conf.bt_stop_list,
2495                        symbol_conf.bt_stop_list_str, "symbol") < 0)
2496                 goto out_free_sym_list;
2497
2498         /*
2499          * A path to symbols of "/" is identical to ""
2500          * reset here for simplicity.
2501          */
2502         symfs = realpath(symbol_conf.symfs, NULL);
2503         if (symfs == NULL)
2504                 symfs = symbol_conf.symfs;
2505         if (strcmp(symfs, "/") == 0)
2506                 symbol_conf.symfs = "";
2507         if (symfs != symbol_conf.symfs)
2508                 free((void *)symfs);
2509
2510         symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2511
2512         symbol_conf.initialized = true;
2513         return 0;
2514
2515 out_free_sym_list:
2516         strlist__delete(symbol_conf.sym_list);
2517         intlist__delete(symbol_conf.addr_list);
2518 out_free_tid_list:
2519         intlist__delete(symbol_conf.tid_list);
2520 out_free_pid_list:
2521         intlist__delete(symbol_conf.pid_list);
2522 out_free_comm_list:
2523         strlist__delete(symbol_conf.comm_list);
2524 out_free_dso_list:
2525         strlist__delete(symbol_conf.dso_list);
2526         return -1;
2527 }
2528
2529 void symbol__exit(void)
2530 {
2531         if (!symbol_conf.initialized)
2532                 return;
2533         strlist__delete(symbol_conf.bt_stop_list);
2534         strlist__delete(symbol_conf.sym_list);
2535         strlist__delete(symbol_conf.dso_list);
2536         strlist__delete(symbol_conf.comm_list);
2537         intlist__delete(symbol_conf.tid_list);
2538         intlist__delete(symbol_conf.pid_list);
2539         intlist__delete(symbol_conf.addr_list);
2540         vmlinux_path__exit();
2541         symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2542         symbol_conf.bt_stop_list = NULL;
2543         symbol_conf.initialized = false;
2544 }
2545
2546 int symbol__config_symfs(const struct option *opt __maybe_unused,
2547                          const char *dir, int unset __maybe_unused)
2548 {
2549         char *bf = NULL;
2550         int ret;
2551
2552         symbol_conf.symfs = strdup(dir);
2553         if (symbol_conf.symfs == NULL)
2554                 return -ENOMEM;
2555
2556         /* skip the locally configured cache if a symfs is given, and
2557          * config buildid dir to symfs/.debug
2558          */
2559         ret = asprintf(&bf, "%s/%s", dir, ".debug");
2560         if (ret < 0)
2561                 return -ENOMEM;
2562
2563         set_buildid_dir(bf);
2564
2565         free(bf);
2566         return 0;
2567 }
2568
2569 struct mem_info *mem_info__get(struct mem_info *mi)
2570 {
2571         if (mi)
2572                 refcount_inc(&mi->refcnt);
2573         return mi;
2574 }
2575
2576 void mem_info__put(struct mem_info *mi)
2577 {
2578         if (mi && refcount_dec_and_test(&mi->refcnt)) {
2579                 addr_map_symbol__exit(&mi->iaddr);
2580                 addr_map_symbol__exit(&mi->daddr);
2581                 free(mi);
2582         }
2583 }
2584
2585 struct mem_info *mem_info__new(void)
2586 {
2587         struct mem_info *mi = zalloc(sizeof(*mi));
2588
2589         if (mi)
2590                 refcount_set(&mi->refcnt, 1);
2591         return mi;
2592 }
2593
2594 /*
2595  * Checks that user supplied symbol kernel files are accessible because
2596  * the default mechanism for accessing elf files fails silently. i.e. if
2597  * debug syms for a build ID aren't found perf carries on normally. When
2598  * they are user supplied we should assume that the user doesn't want to
2599  * silently fail.
2600  */
2601 int symbol__validate_sym_arguments(void)
2602 {
2603         if (symbol_conf.vmlinux_name &&
2604             access(symbol_conf.vmlinux_name, R_OK)) {
2605                 pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
2606                 return -EINVAL;
2607         }
2608         if (symbol_conf.kallsyms_name &&
2609             access(symbol_conf.kallsyms_name, R_OK)) {
2610                 pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
2611                 return -EINVAL;
2612         }
2613         return 0;
2614 }