Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
44static int dso__load_kernel_sym(struct dso *dso, struct map *map);
45static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
46static bool symbol__is_idle(const char *name);
47
48int vmlinux_path__nr_entries;
49char **vmlinux_path;
50
51struct map_list_node {
52 struct list_head node;
53 struct map *map;
54};
55
56struct symbol_conf symbol_conf = {
57 .nanosecs = false,
58 .use_modules = true,
59 .try_vmlinux_path = true,
60 .demangle = true,
61 .demangle_kernel = false,
62 .cumulate_callchain = true,
63 .time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */
64 .show_hist_headers = true,
65 .symfs = "",
66 .event_group = true,
67 .inline_name = true,
68 .res_sample = 0,
69};
70
71static enum dso_binary_type binary_type_symtab[] = {
72 DSO_BINARY_TYPE__KALLSYMS,
73 DSO_BINARY_TYPE__GUEST_KALLSYMS,
74 DSO_BINARY_TYPE__JAVA_JIT,
75 DSO_BINARY_TYPE__DEBUGLINK,
76 DSO_BINARY_TYPE__BUILD_ID_CACHE,
77 DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
78 DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
79 DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
80 DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
81 DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
82 DSO_BINARY_TYPE__GUEST_KMODULE,
83 DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
84 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
85 DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
86 DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
87 DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
88 DSO_BINARY_TYPE__NOT_FOUND,
89};
90
91#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
92
93static struct map_list_node *map_list_node__new(void)
94{
95 return malloc(sizeof(struct map_list_node));
96}
97
98static 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
104static 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
114const char * __weak arch__normalize_symbol_name(const char *name)
115{
116 return name;
117}
118
119int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
120{
121 return strcmp(namea, nameb);
122}
123
124int __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
130int __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
142static 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
191void 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);
203again:
204 nd = rb_next(&curr->rb_node);
205 next = rb_entry(nd, struct symbol, rb_node);
206
207 if (!nd)
208 break;
209
210 if (curr->start != next->start)
211 continue;
212
213 if (choose_best_symbol(curr, next) == SYMBOL_A) {
214 if (next->type == STT_GNU_IFUNC)
215 curr->ifunc_alias = true;
216 rb_erase_cached(&next->rb_node, symbols);
217 symbol__delete(next);
218 goto again;
219 } else {
220 if (curr->type == STT_GNU_IFUNC)
221 next->ifunc_alias = true;
222 nd = rb_next(&curr->rb_node);
223 rb_erase_cached(&curr->rb_node, symbols);
224 symbol__delete(curr);
225 }
226 }
227}
228
229/* Update zero-sized symbols using the address of the next symbol */
230void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
231{
232 struct rb_node *nd, *prevnd = rb_first_cached(symbols);
233 struct symbol *curr, *prev;
234
235 if (prevnd == NULL)
236 return;
237
238 curr = rb_entry(prevnd, struct symbol, rb_node);
239
240 for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
241 prev = curr;
242 curr = rb_entry(nd, struct symbol, rb_node);
243
244 /*
245 * On some architecture kernel text segment start is located at
246 * some low memory address, while modules are located at high
247 * memory addresses (or vice versa). The gap between end of
248 * kernel text segment and beginning of first module's text
249 * segment is very big. Therefore do not fill this gap and do
250 * not assign it to the kernel dso map (kallsyms).
251 *
252 * In kallsyms, it determines module symbols using '[' character
253 * like in:
254 * ffffffffc1937000 T hdmi_driver_init [snd_hda_codec_hdmi]
255 */
256 if (prev->end == prev->start) {
257 /* Last kernel/module symbol mapped to end of page */
258 if (is_kallsyms && (!strchr(prev->name, '[') !=
259 !strchr(curr->name, '[')))
260 prev->end = roundup(prev->end + 4096, 4096);
261 else
262 prev->end = curr->start;
263
264 pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
265 __func__, prev->name, prev->end);
266 }
267 }
268
269 /* Last entry */
270 if (curr->end == curr->start)
271 curr->end = roundup(curr->start, 4096) + 4096;
272}
273
274void maps__fixup_end(struct maps *maps)
275{
276 struct map_rb_node *prev = NULL, *curr;
277
278 down_write(maps__lock(maps));
279
280 maps__for_each_entry(maps, curr) {
281 if (prev != NULL && !map__end(prev->map))
282 map__set_end(prev->map, map__start(curr->map));
283
284 prev = curr;
285 }
286
287 /*
288 * We still haven't the actual symbols, so guess the
289 * last map final address.
290 */
291 if (curr && !map__end(curr->map))
292 map__set_end(curr->map, ~0ULL);
293
294 up_write(maps__lock(maps));
295}
296
297struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
298{
299 size_t namelen = strlen(name) + 1;
300 struct symbol *sym = calloc(1, (symbol_conf.priv_size +
301 sizeof(*sym) + namelen));
302 if (sym == NULL)
303 return NULL;
304
305 if (symbol_conf.priv_size) {
306 if (symbol_conf.init_annotation) {
307 struct annotation *notes = (void *)sym;
308 annotation__init(notes);
309 }
310 sym = ((void *)sym) + symbol_conf.priv_size;
311 }
312
313 sym->start = start;
314 sym->end = len ? start + len : start;
315 sym->type = type;
316 sym->binding = binding;
317 sym->namelen = namelen - 1;
318
319 pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
320 __func__, name, start, sym->end);
321 memcpy(sym->name, name, namelen);
322
323 return sym;
324}
325
326void symbol__delete(struct symbol *sym)
327{
328 if (symbol_conf.priv_size) {
329 if (symbol_conf.init_annotation) {
330 struct annotation *notes = symbol__annotation(sym);
331
332 annotation__exit(notes);
333 }
334 }
335 free(((void *)sym) - symbol_conf.priv_size);
336}
337
338void symbols__delete(struct rb_root_cached *symbols)
339{
340 struct symbol *pos;
341 struct rb_node *next = rb_first_cached(symbols);
342
343 while (next) {
344 pos = rb_entry(next, struct symbol, rb_node);
345 next = rb_next(&pos->rb_node);
346 rb_erase_cached(&pos->rb_node, symbols);
347 symbol__delete(pos);
348 }
349}
350
351void __symbols__insert(struct rb_root_cached *symbols,
352 struct symbol *sym, bool kernel)
353{
354 struct rb_node **p = &symbols->rb_root.rb_node;
355 struct rb_node *parent = NULL;
356 const u64 ip = sym->start;
357 struct symbol *s;
358 bool leftmost = true;
359
360 if (kernel) {
361 const char *name = sym->name;
362 /*
363 * ppc64 uses function descriptors and appends a '.' to the
364 * start of every instruction address. Remove it.
365 */
366 if (name[0] == '.')
367 name++;
368 sym->idle = symbol__is_idle(name);
369 }
370
371 while (*p != NULL) {
372 parent = *p;
373 s = rb_entry(parent, struct symbol, rb_node);
374 if (ip < s->start)
375 p = &(*p)->rb_left;
376 else {
377 p = &(*p)->rb_right;
378 leftmost = false;
379 }
380 }
381 rb_link_node(&sym->rb_node, parent, p);
382 rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
383}
384
385void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
386{
387 __symbols__insert(symbols, sym, false);
388}
389
390static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
391{
392 struct rb_node *n;
393
394 if (symbols == NULL)
395 return NULL;
396
397 n = symbols->rb_root.rb_node;
398
399 while (n) {
400 struct symbol *s = rb_entry(n, struct symbol, rb_node);
401
402 if (ip < s->start)
403 n = n->rb_left;
404 else if (ip > s->end || (ip == s->end && ip != s->start))
405 n = n->rb_right;
406 else
407 return s;
408 }
409
410 return NULL;
411}
412
413static struct symbol *symbols__first(struct rb_root_cached *symbols)
414{
415 struct rb_node *n = rb_first_cached(symbols);
416
417 if (n)
418 return rb_entry(n, struct symbol, rb_node);
419
420 return NULL;
421}
422
423static struct symbol *symbols__last(struct rb_root_cached *symbols)
424{
425 struct rb_node *n = rb_last(&symbols->rb_root);
426
427 if (n)
428 return rb_entry(n, struct symbol, rb_node);
429
430 return NULL;
431}
432
433static struct symbol *symbols__next(struct symbol *sym)
434{
435 struct rb_node *n = rb_next(&sym->rb_node);
436
437 if (n)
438 return rb_entry(n, struct symbol, rb_node);
439
440 return NULL;
441}
442
443static void symbols__insert_by_name(struct rb_root_cached *symbols, struct symbol *sym)
444{
445 struct rb_node **p = &symbols->rb_root.rb_node;
446 struct rb_node *parent = NULL;
447 struct symbol_name_rb_node *symn, *s;
448 bool leftmost = true;
449
450 symn = container_of(sym, struct symbol_name_rb_node, sym);
451
452 while (*p != NULL) {
453 parent = *p;
454 s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
455 if (strcmp(sym->name, s->sym.name) < 0)
456 p = &(*p)->rb_left;
457 else {
458 p = &(*p)->rb_right;
459 leftmost = false;
460 }
461 }
462 rb_link_node(&symn->rb_node, parent, p);
463 rb_insert_color_cached(&symn->rb_node, symbols, leftmost);
464}
465
466static void symbols__sort_by_name(struct rb_root_cached *symbols,
467 struct rb_root_cached *source)
468{
469 struct rb_node *nd;
470
471 for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
472 struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
473 symbols__insert_by_name(symbols, pos);
474 }
475}
476
477int symbol__match_symbol_name(const char *name, const char *str,
478 enum symbol_tag_include includes)
479{
480 const char *versioning;
481
482 if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
483 (versioning = strstr(name, "@@"))) {
484 int len = strlen(str);
485
486 if (len < versioning - name)
487 len = versioning - name;
488
489 return arch__compare_symbol_names_n(name, str, len);
490 } else
491 return arch__compare_symbol_names(name, str);
492}
493
494static struct symbol *symbols__find_by_name(struct rb_root_cached *symbols,
495 const char *name,
496 enum symbol_tag_include includes)
497{
498 struct rb_node *n;
499 struct symbol_name_rb_node *s = NULL;
500
501 if (symbols == NULL)
502 return NULL;
503
504 n = symbols->rb_root.rb_node;
505
506 while (n) {
507 int cmp;
508
509 s = rb_entry(n, struct symbol_name_rb_node, rb_node);
510 cmp = symbol__match_symbol_name(s->sym.name, name, includes);
511
512 if (cmp > 0)
513 n = n->rb_left;
514 else if (cmp < 0)
515 n = n->rb_right;
516 else
517 break;
518 }
519
520 if (n == NULL)
521 return NULL;
522
523 if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY)
524 /* return first symbol that has same name (if any) */
525 for (n = rb_prev(n); n; n = rb_prev(n)) {
526 struct symbol_name_rb_node *tmp;
527
528 tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
529 if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
530 break;
531
532 s = tmp;
533 }
534
535 return &s->sym;
536}
537
538void dso__reset_find_symbol_cache(struct dso *dso)
539{
540 dso->last_find_result.addr = 0;
541 dso->last_find_result.symbol = NULL;
542}
543
544void dso__insert_symbol(struct dso *dso, struct symbol *sym)
545{
546 __symbols__insert(&dso->symbols, sym, dso->kernel);
547
548 /* update the symbol cache if necessary */
549 if (dso->last_find_result.addr >= sym->start &&
550 (dso->last_find_result.addr < sym->end ||
551 sym->start == sym->end)) {
552 dso->last_find_result.symbol = sym;
553 }
554}
555
556void dso__delete_symbol(struct dso *dso, struct symbol *sym)
557{
558 rb_erase_cached(&sym->rb_node, &dso->symbols);
559 symbol__delete(sym);
560 dso__reset_find_symbol_cache(dso);
561}
562
563struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
564{
565 if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
566 dso->last_find_result.addr = addr;
567 dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
568 }
569
570 return dso->last_find_result.symbol;
571}
572
573struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr)
574{
575 return symbols__find(&dso->symbols, addr);
576}
577
578struct symbol *dso__first_symbol(struct dso *dso)
579{
580 return symbols__first(&dso->symbols);
581}
582
583struct symbol *dso__last_symbol(struct dso *dso)
584{
585 return symbols__last(&dso->symbols);
586}
587
588struct symbol *dso__next_symbol(struct symbol *sym)
589{
590 return symbols__next(sym);
591}
592
593struct symbol *symbol__next_by_name(struct symbol *sym)
594{
595 struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
596 struct rb_node *n = rb_next(&s->rb_node);
597
598 return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
599}
600
601 /*
602 * Returns first symbol that matched with @name.
603 */
604struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name)
605{
606 struct symbol *s = symbols__find_by_name(&dso->symbol_names, name,
607 SYMBOL_TAG_INCLUDE__NONE);
608 if (!s)
609 s = symbols__find_by_name(&dso->symbol_names, name,
610 SYMBOL_TAG_INCLUDE__DEFAULT_ONLY);
611 return s;
612}
613
614void dso__sort_by_name(struct dso *dso)
615{
616 dso__set_sorted_by_name(dso);
617 return symbols__sort_by_name(&dso->symbol_names, &dso->symbols);
618}
619
620/*
621 * While we find nice hex chars, build a long_val.
622 * Return number of chars processed.
623 */
624static int hex2u64(const char *ptr, u64 *long_val)
625{
626 char *p;
627
628 *long_val = strtoull(ptr, &p, 16);
629
630 return p - ptr;
631}
632
633
634int modules__parse(const char *filename, void *arg,
635 int (*process_module)(void *arg, const char *name,
636 u64 start, u64 size))
637{
638 char *line = NULL;
639 size_t n;
640 FILE *file;
641 int err = 0;
642
643 file = fopen(filename, "r");
644 if (file == NULL)
645 return -1;
646
647 while (1) {
648 char name[PATH_MAX];
649 u64 start, size;
650 char *sep, *endptr;
651 ssize_t line_len;
652
653 line_len = getline(&line, &n, file);
654 if (line_len < 0) {
655 if (feof(file))
656 break;
657 err = -1;
658 goto out;
659 }
660
661 if (!line) {
662 err = -1;
663 goto out;
664 }
665
666 line[--line_len] = '\0'; /* \n */
667
668 sep = strrchr(line, 'x');
669 if (sep == NULL)
670 continue;
671
672 hex2u64(sep + 1, &start);
673
674 sep = strchr(line, ' ');
675 if (sep == NULL)
676 continue;
677
678 *sep = '\0';
679
680 scnprintf(name, sizeof(name), "[%s]", line);
681
682 size = strtoul(sep + 1, &endptr, 0);
683 if (*endptr != ' ' && *endptr != '\t')
684 continue;
685
686 err = process_module(arg, name, start, size);
687 if (err)
688 break;
689 }
690out:
691 free(line);
692 fclose(file);
693 return err;
694}
695
696/*
697 * These are symbols in the kernel image, so make sure that
698 * sym is from a kernel DSO.
699 */
700static bool symbol__is_idle(const char *name)
701{
702 const char * const idle_symbols[] = {
703 "acpi_idle_do_entry",
704 "acpi_processor_ffh_cstate_enter",
705 "arch_cpu_idle",
706 "cpu_idle",
707 "cpu_startup_entry",
708 "idle_cpu",
709 "intel_idle",
710 "default_idle",
711 "native_safe_halt",
712 "enter_idle",
713 "exit_idle",
714 "mwait_idle",
715 "mwait_idle_with_hints",
716 "mwait_idle_with_hints.constprop.0",
717 "poll_idle",
718 "ppc64_runlatch_off",
719 "pseries_dedicated_idle_sleep",
720 "psw_idle",
721 "psw_idle_exit",
722 NULL
723 };
724 int i;
725 static struct strlist *idle_symbols_list;
726
727 if (idle_symbols_list)
728 return strlist__has_entry(idle_symbols_list, name);
729
730 idle_symbols_list = strlist__new(NULL, NULL);
731
732 for (i = 0; idle_symbols[i]; i++)
733 strlist__add(idle_symbols_list, idle_symbols[i]);
734
735 return strlist__has_entry(idle_symbols_list, name);
736}
737
738static int map__process_kallsym_symbol(void *arg, const char *name,
739 char type, u64 start)
740{
741 struct symbol *sym;
742 struct dso *dso = arg;
743 struct rb_root_cached *root = &dso->symbols;
744
745 if (!symbol_type__filter(type))
746 return 0;
747
748 /* Ignore local symbols for ARM modules */
749 if (name[0] == '$')
750 return 0;
751
752 /*
753 * module symbols are not sorted so we add all
754 * symbols, setting length to 0, and rely on
755 * symbols__fixup_end() to fix it up.
756 */
757 sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
758 if (sym == NULL)
759 return -ENOMEM;
760 /*
761 * We will pass the symbols to the filter later, in
762 * map__split_kallsyms, when we have split the maps per module
763 */
764 __symbols__insert(root, sym, !strchr(name, '['));
765
766 return 0;
767}
768
769/*
770 * Loads the function entries in /proc/kallsyms into kernel_map->dso,
771 * so that we can in the next step set the symbol ->end address and then
772 * call kernel_maps__split_kallsyms.
773 */
774static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
775{
776 return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
777}
778
779static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
780{
781 struct map *curr_map;
782 struct symbol *pos;
783 int count = 0;
784 struct rb_root_cached old_root = dso->symbols;
785 struct rb_root_cached *root = &dso->symbols;
786 struct rb_node *next = rb_first_cached(root);
787
788 if (!kmaps)
789 return -1;
790
791 *root = RB_ROOT_CACHED;
792
793 while (next) {
794 struct dso *curr_map_dso;
795 char *module;
796
797 pos = rb_entry(next, struct symbol, rb_node);
798 next = rb_next(&pos->rb_node);
799
800 rb_erase_cached(&pos->rb_node, &old_root);
801 RB_CLEAR_NODE(&pos->rb_node);
802 module = strchr(pos->name, '\t');
803 if (module)
804 *module = '\0';
805
806 curr_map = maps__find(kmaps, pos->start);
807
808 if (!curr_map) {
809 symbol__delete(pos);
810 continue;
811 }
812 curr_map_dso = map__dso(curr_map);
813 pos->start -= map__start(curr_map) - map__pgoff(curr_map);
814 if (pos->end > map__end(curr_map))
815 pos->end = map__end(curr_map);
816 if (pos->end)
817 pos->end -= map__start(curr_map) - map__pgoff(curr_map);
818 symbols__insert(&curr_map_dso->symbols, pos);
819 ++count;
820 }
821
822 /* Symbols have been adjusted */
823 dso->adjust_symbols = 1;
824
825 return count;
826}
827
828/*
829 * Split the symbols into maps, making sure there are no overlaps, i.e. the
830 * kernel range is broken in several maps, named [kernel].N, as we don't have
831 * the original ELF section names vmlinux have.
832 */
833static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
834 struct map *initial_map)
835{
836 struct machine *machine;
837 struct map *curr_map = initial_map;
838 struct symbol *pos;
839 int count = 0, moved = 0;
840 struct rb_root_cached *root = &dso->symbols;
841 struct rb_node *next = rb_first_cached(root);
842 int kernel_range = 0;
843 bool x86_64;
844
845 if (!kmaps)
846 return -1;
847
848 machine = maps__machine(kmaps);
849
850 x86_64 = machine__is(machine, "x86_64");
851
852 while (next) {
853 char *module;
854
855 pos = rb_entry(next, struct symbol, rb_node);
856 next = rb_next(&pos->rb_node);
857
858 module = strchr(pos->name, '\t');
859 if (module) {
860 struct dso *curr_map_dso;
861
862 if (!symbol_conf.use_modules)
863 goto discard_symbol;
864
865 *module++ = '\0';
866 curr_map_dso = map__dso(curr_map);
867 if (strcmp(curr_map_dso->short_name, module)) {
868 if (RC_CHK_ACCESS(curr_map) != RC_CHK_ACCESS(initial_map) &&
869 dso->kernel == DSO_SPACE__KERNEL_GUEST &&
870 machine__is_default_guest(machine)) {
871 /*
872 * We assume all symbols of a module are
873 * continuous in * kallsyms, so curr_map
874 * points to a module and all its
875 * symbols are in its kmap. Mark it as
876 * loaded.
877 */
878 dso__set_loaded(curr_map_dso);
879 }
880
881 curr_map = maps__find_by_name(kmaps, module);
882 if (curr_map == NULL) {
883 pr_debug("%s/proc/{kallsyms,modules} "
884 "inconsistency while looking "
885 "for \"%s\" module!\n",
886 machine->root_dir, module);
887 curr_map = initial_map;
888 goto discard_symbol;
889 }
890 curr_map_dso = map__dso(curr_map);
891 if (curr_map_dso->loaded &&
892 !machine__is_default_guest(machine))
893 goto discard_symbol;
894 }
895 /*
896 * So that we look just like we get from .ko files,
897 * i.e. not prelinked, relative to initial_map->start.
898 */
899 pos->start = map__map_ip(curr_map, pos->start);
900 pos->end = map__map_ip(curr_map, pos->end);
901 } else if (x86_64 && is_entry_trampoline(pos->name)) {
902 /*
903 * These symbols are not needed anymore since the
904 * trampoline maps refer to the text section and it's
905 * symbols instead. Avoid having to deal with
906 * relocations, and the assumption that the first symbol
907 * is the start of kernel text, by simply removing the
908 * symbols at this point.
909 */
910 goto discard_symbol;
911 } else if (curr_map != initial_map) {
912 char dso_name[PATH_MAX];
913 struct dso *ndso;
914
915 if (delta) {
916 /* Kernel was relocated at boot time */
917 pos->start -= delta;
918 pos->end -= delta;
919 }
920
921 if (count == 0) {
922 curr_map = initial_map;
923 goto add_symbol;
924 }
925
926 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
927 snprintf(dso_name, sizeof(dso_name),
928 "[guest.kernel].%d",
929 kernel_range++);
930 else
931 snprintf(dso_name, sizeof(dso_name),
932 "[kernel].%d",
933 kernel_range++);
934
935 ndso = dso__new(dso_name);
936 if (ndso == NULL)
937 return -1;
938
939 ndso->kernel = dso->kernel;
940
941 curr_map = map__new2(pos->start, ndso);
942 if (curr_map == NULL) {
943 dso__put(ndso);
944 return -1;
945 }
946
947 map__set_map_ip(curr_map, identity__map_ip);
948 map__set_unmap_ip(curr_map, identity__map_ip);
949 if (maps__insert(kmaps, curr_map)) {
950 dso__put(ndso);
951 return -1;
952 }
953 ++kernel_range;
954 } else if (delta) {
955 /* Kernel was relocated at boot time */
956 pos->start -= delta;
957 pos->end -= delta;
958 }
959add_symbol:
960 if (curr_map != initial_map) {
961 struct dso *curr_map_dso = map__dso(curr_map);
962
963 rb_erase_cached(&pos->rb_node, root);
964 symbols__insert(&curr_map_dso->symbols, pos);
965 ++moved;
966 } else
967 ++count;
968
969 continue;
970discard_symbol:
971 rb_erase_cached(&pos->rb_node, root);
972 symbol__delete(pos);
973 }
974
975 if (curr_map != initial_map &&
976 dso->kernel == DSO_SPACE__KERNEL_GUEST &&
977 machine__is_default_guest(maps__machine(kmaps))) {
978 dso__set_loaded(map__dso(curr_map));
979 }
980
981 return count + moved;
982}
983
984bool symbol__restricted_filename(const char *filename,
985 const char *restricted_filename)
986{
987 bool restricted = false;
988
989 if (symbol_conf.kptr_restrict) {
990 char *r = realpath(filename, NULL);
991
992 if (r != NULL) {
993 restricted = strcmp(r, restricted_filename) == 0;
994 free(r);
995 return restricted;
996 }
997 }
998
999 return restricted;
1000}
1001
1002struct module_info {
1003 struct rb_node rb_node;
1004 char *name;
1005 u64 start;
1006};
1007
1008static void add_module(struct module_info *mi, struct rb_root *modules)
1009{
1010 struct rb_node **p = &modules->rb_node;
1011 struct rb_node *parent = NULL;
1012 struct module_info *m;
1013
1014 while (*p != NULL) {
1015 parent = *p;
1016 m = rb_entry(parent, struct module_info, rb_node);
1017 if (strcmp(mi->name, m->name) < 0)
1018 p = &(*p)->rb_left;
1019 else
1020 p = &(*p)->rb_right;
1021 }
1022 rb_link_node(&mi->rb_node, parent, p);
1023 rb_insert_color(&mi->rb_node, modules);
1024}
1025
1026static void delete_modules(struct rb_root *modules)
1027{
1028 struct module_info *mi;
1029 struct rb_node *next = rb_first(modules);
1030
1031 while (next) {
1032 mi = rb_entry(next, struct module_info, rb_node);
1033 next = rb_next(&mi->rb_node);
1034 rb_erase(&mi->rb_node, modules);
1035 zfree(&mi->name);
1036 free(mi);
1037 }
1038}
1039
1040static struct module_info *find_module(const char *name,
1041 struct rb_root *modules)
1042{
1043 struct rb_node *n = modules->rb_node;
1044
1045 while (n) {
1046 struct module_info *m;
1047 int cmp;
1048
1049 m = rb_entry(n, struct module_info, rb_node);
1050 cmp = strcmp(name, m->name);
1051 if (cmp < 0)
1052 n = n->rb_left;
1053 else if (cmp > 0)
1054 n = n->rb_right;
1055 else
1056 return m;
1057 }
1058
1059 return NULL;
1060}
1061
1062static int __read_proc_modules(void *arg, const char *name, u64 start,
1063 u64 size __maybe_unused)
1064{
1065 struct rb_root *modules = arg;
1066 struct module_info *mi;
1067
1068 mi = zalloc(sizeof(struct module_info));
1069 if (!mi)
1070 return -ENOMEM;
1071
1072 mi->name = strdup(name);
1073 mi->start = start;
1074
1075 if (!mi->name) {
1076 free(mi);
1077 return -ENOMEM;
1078 }
1079
1080 add_module(mi, modules);
1081
1082 return 0;
1083}
1084
1085static int read_proc_modules(const char *filename, struct rb_root *modules)
1086{
1087 if (symbol__restricted_filename(filename, "/proc/modules"))
1088 return -1;
1089
1090 if (modules__parse(filename, modules, __read_proc_modules)) {
1091 delete_modules(modules);
1092 return -1;
1093 }
1094
1095 return 0;
1096}
1097
1098int compare_proc_modules(const char *from, const char *to)
1099{
1100 struct rb_root from_modules = RB_ROOT;
1101 struct rb_root to_modules = RB_ROOT;
1102 struct rb_node *from_node, *to_node;
1103 struct module_info *from_m, *to_m;
1104 int ret = -1;
1105
1106 if (read_proc_modules(from, &from_modules))
1107 return -1;
1108
1109 if (read_proc_modules(to, &to_modules))
1110 goto out_delete_from;
1111
1112 from_node = rb_first(&from_modules);
1113 to_node = rb_first(&to_modules);
1114 while (from_node) {
1115 if (!to_node)
1116 break;
1117
1118 from_m = rb_entry(from_node, struct module_info, rb_node);
1119 to_m = rb_entry(to_node, struct module_info, rb_node);
1120
1121 if (from_m->start != to_m->start ||
1122 strcmp(from_m->name, to_m->name))
1123 break;
1124
1125 from_node = rb_next(from_node);
1126 to_node = rb_next(to_node);
1127 }
1128
1129 if (!from_node && !to_node)
1130 ret = 0;
1131
1132 delete_modules(&to_modules);
1133out_delete_from:
1134 delete_modules(&from_modules);
1135
1136 return ret;
1137}
1138
1139static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1140{
1141 struct rb_root modules = RB_ROOT;
1142 struct map_rb_node *old_node;
1143 int err;
1144
1145 err = read_proc_modules(filename, &modules);
1146 if (err)
1147 return err;
1148
1149 maps__for_each_entry(kmaps, old_node) {
1150 struct map *old_map = old_node->map;
1151 struct module_info *mi;
1152 struct dso *dso;
1153
1154 if (!__map__is_kmodule(old_map)) {
1155 continue;
1156 }
1157 dso = map__dso(old_map);
1158 /* Module must be in memory at the same address */
1159 mi = find_module(dso->short_name, &modules);
1160 if (!mi || mi->start != map__start(old_map)) {
1161 err = -EINVAL;
1162 goto out;
1163 }
1164 }
1165out:
1166 delete_modules(&modules);
1167 return err;
1168}
1169
1170/*
1171 * If kallsyms is referenced by name then we look for filename in the same
1172 * directory.
1173 */
1174static bool filename_from_kallsyms_filename(char *filename,
1175 const char *base_name,
1176 const char *kallsyms_filename)
1177{
1178 char *name;
1179
1180 strcpy(filename, kallsyms_filename);
1181 name = strrchr(filename, '/');
1182 if (!name)
1183 return false;
1184
1185 name += 1;
1186
1187 if (!strcmp(name, "kallsyms")) {
1188 strcpy(name, base_name);
1189 return true;
1190 }
1191
1192 return false;
1193}
1194
1195static int validate_kcore_modules(const char *kallsyms_filename,
1196 struct map *map)
1197{
1198 struct maps *kmaps = map__kmaps(map);
1199 char modules_filename[PATH_MAX];
1200
1201 if (!kmaps)
1202 return -EINVAL;
1203
1204 if (!filename_from_kallsyms_filename(modules_filename, "modules",
1205 kallsyms_filename))
1206 return -EINVAL;
1207
1208 if (do_validate_kcore_modules(modules_filename, kmaps))
1209 return -EINVAL;
1210
1211 return 0;
1212}
1213
1214static int validate_kcore_addresses(const char *kallsyms_filename,
1215 struct map *map)
1216{
1217 struct kmap *kmap = map__kmap(map);
1218
1219 if (!kmap)
1220 return -EINVAL;
1221
1222 if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1223 u64 start;
1224
1225 if (kallsyms__get_function_start(kallsyms_filename,
1226 kmap->ref_reloc_sym->name, &start))
1227 return -ENOENT;
1228 if (start != kmap->ref_reloc_sym->addr)
1229 return -EINVAL;
1230 }
1231
1232 return validate_kcore_modules(kallsyms_filename, map);
1233}
1234
1235struct kcore_mapfn_data {
1236 struct dso *dso;
1237 struct list_head maps;
1238};
1239
1240static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1241{
1242 struct kcore_mapfn_data *md = data;
1243 struct map_list_node *list_node = map_list_node__new();
1244
1245 if (!list_node)
1246 return -ENOMEM;
1247
1248 list_node->map = map__new2(start, md->dso);
1249 if (!list_node->map) {
1250 free(list_node);
1251 return -ENOMEM;
1252 }
1253
1254 map__set_end(list_node->map, map__start(list_node->map) + len);
1255 map__set_pgoff(list_node->map, pgoff);
1256
1257 list_add(&list_node->node, &md->maps);
1258
1259 return 0;
1260}
1261
1262/*
1263 * Merges map into maps by splitting the new map within the existing map
1264 * regions.
1265 */
1266int maps__merge_in(struct maps *kmaps, struct map *new_map)
1267{
1268 struct map_rb_node *rb_node;
1269 LIST_HEAD(merged);
1270 int err = 0;
1271
1272 maps__for_each_entry(kmaps, rb_node) {
1273 struct map *old_map = rb_node->map;
1274
1275 /* no overload with this one */
1276 if (map__end(new_map) < map__start(old_map) ||
1277 map__start(new_map) >= map__end(old_map))
1278 continue;
1279
1280 if (map__start(new_map) < map__start(old_map)) {
1281 /*
1282 * |new......
1283 * |old....
1284 */
1285 if (map__end(new_map) < map__end(old_map)) {
1286 /*
1287 * |new......| -> |new..|
1288 * |old....| -> |old....|
1289 */
1290 map__set_end(new_map, map__start(old_map));
1291 } else {
1292 /*
1293 * |new.............| -> |new..| |new..|
1294 * |old....| -> |old....|
1295 */
1296 struct map_list_node *m = map_list_node__new();
1297
1298 if (!m) {
1299 err = -ENOMEM;
1300 goto out;
1301 }
1302
1303 m->map = map__clone(new_map);
1304 if (!m->map) {
1305 free(m);
1306 err = -ENOMEM;
1307 goto out;
1308 }
1309
1310 map__set_end(m->map, map__start(old_map));
1311 list_add_tail(&m->node, &merged);
1312 map__add_pgoff(new_map, map__end(old_map) - map__start(new_map));
1313 map__set_start(new_map, map__end(old_map));
1314 }
1315 } else {
1316 /*
1317 * |new......
1318 * |old....
1319 */
1320 if (map__end(new_map) < map__end(old_map)) {
1321 /*
1322 * |new..| -> x
1323 * |old.........| -> |old.........|
1324 */
1325 map__put(new_map);
1326 new_map = NULL;
1327 break;
1328 } else {
1329 /*
1330 * |new......| -> |new...|
1331 * |old....| -> |old....|
1332 */
1333 map__add_pgoff(new_map, map__end(old_map) - map__start(new_map));
1334 map__set_start(new_map, map__end(old_map));
1335 }
1336 }
1337 }
1338
1339out:
1340 while (!list_empty(&merged)) {
1341 struct map_list_node *old_node;
1342
1343 old_node = list_entry(merged.next, struct map_list_node, node);
1344 list_del_init(&old_node->node);
1345 if (!err)
1346 err = maps__insert(kmaps, old_node->map);
1347 map__put(old_node->map);
1348 free(old_node);
1349 }
1350
1351 if (new_map) {
1352 if (!err)
1353 err = maps__insert(kmaps, new_map);
1354 map__put(new_map);
1355 }
1356 return err;
1357}
1358
1359static int dso__load_kcore(struct dso *dso, struct map *map,
1360 const char *kallsyms_filename)
1361{
1362 struct maps *kmaps = map__kmaps(map);
1363 struct kcore_mapfn_data md;
1364 struct map *replacement_map = NULL;
1365 struct map_rb_node *old_node, *next;
1366 struct machine *machine;
1367 bool is_64_bit;
1368 int err, fd;
1369 char kcore_filename[PATH_MAX];
1370 u64 stext;
1371
1372 if (!kmaps)
1373 return -EINVAL;
1374
1375 machine = maps__machine(kmaps);
1376
1377 /* This function requires that the map is the kernel map */
1378 if (!__map__is_kernel(map))
1379 return -EINVAL;
1380
1381 if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1382 kallsyms_filename))
1383 return -EINVAL;
1384
1385 /* Modules and kernel must be present at their original addresses */
1386 if (validate_kcore_addresses(kallsyms_filename, map))
1387 return -EINVAL;
1388
1389 md.dso = dso;
1390 INIT_LIST_HEAD(&md.maps);
1391
1392 fd = open(kcore_filename, O_RDONLY);
1393 if (fd < 0) {
1394 pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1395 kcore_filename);
1396 return -EINVAL;
1397 }
1398
1399 /* Read new maps into temporary lists */
1400 err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md,
1401 &is_64_bit);
1402 if (err)
1403 goto out_err;
1404 dso->is_64_bit = is_64_bit;
1405
1406 if (list_empty(&md.maps)) {
1407 err = -EINVAL;
1408 goto out_err;
1409 }
1410
1411 /* Remove old maps */
1412 maps__for_each_entry_safe(kmaps, old_node, next) {
1413 struct map *old_map = old_node->map;
1414
1415 /*
1416 * We need to preserve eBPF maps even if they are
1417 * covered by kcore, because we need to access
1418 * eBPF dso for source data.
1419 */
1420 if (old_map != map && !__map__is_bpf_prog(old_map))
1421 maps__remove(kmaps, old_map);
1422 }
1423 machine->trampolines_mapped = false;
1424
1425 /* Find the kernel map using the '_stext' symbol */
1426 if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1427 u64 replacement_size = 0;
1428 struct map_list_node *new_node;
1429
1430 list_for_each_entry(new_node, &md.maps, node) {
1431 struct map *new_map = new_node->map;
1432 u64 new_size = map__size(new_map);
1433
1434 if (!(stext >= map__start(new_map) && stext < map__end(new_map)))
1435 continue;
1436
1437 /*
1438 * On some architectures, ARM64 for example, the kernel
1439 * text can get allocated inside of the vmalloc segment.
1440 * Select the smallest matching segment, in case stext
1441 * falls within more than one in the list.
1442 */
1443 if (!replacement_map || new_size < replacement_size) {
1444 replacement_map = new_map;
1445 replacement_size = new_size;
1446 }
1447 }
1448 }
1449
1450 if (!replacement_map)
1451 replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map;
1452
1453 /* Add new maps */
1454 while (!list_empty(&md.maps)) {
1455 struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node);
1456 struct map *new_map = new_node->map;
1457
1458 list_del_init(&new_node->node);
1459
1460 if (RC_CHK_ACCESS(new_map) == RC_CHK_ACCESS(replacement_map)) {
1461 map__set_start(map, map__start(new_map));
1462 map__set_end(map, map__end(new_map));
1463 map__set_pgoff(map, map__pgoff(new_map));
1464 map__set_map_ip(map, map__map_ip_ptr(new_map));
1465 map__set_unmap_ip(map, map__unmap_ip_ptr(new_map));
1466 /* Ensure maps are correctly ordered */
1467 map__get(map);
1468 maps__remove(kmaps, map);
1469 err = maps__insert(kmaps, map);
1470 map__put(map);
1471 map__put(new_map);
1472 if (err)
1473 goto out_err;
1474 } else {
1475 /*
1476 * Merge kcore map into existing maps,
1477 * and ensure that current maps (eBPF)
1478 * stay intact.
1479 */
1480 if (maps__merge_in(kmaps, new_map)) {
1481 err = -EINVAL;
1482 goto out_err;
1483 }
1484 }
1485 free(new_node);
1486 }
1487
1488 if (machine__is(machine, "x86_64")) {
1489 u64 addr;
1490
1491 /*
1492 * If one of the corresponding symbols is there, assume the
1493 * entry trampoline maps are too.
1494 */
1495 if (!kallsyms__get_function_start(kallsyms_filename,
1496 ENTRY_TRAMPOLINE_NAME,
1497 &addr))
1498 machine->trampolines_mapped = true;
1499 }
1500
1501 /*
1502 * Set the data type and long name so that kcore can be read via
1503 * dso__data_read_addr().
1504 */
1505 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1506 dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1507 else
1508 dso->binary_type = DSO_BINARY_TYPE__KCORE;
1509 dso__set_long_name(dso, strdup(kcore_filename), true);
1510
1511 close(fd);
1512
1513 if (map__prot(map) & PROT_EXEC)
1514 pr_debug("Using %s for kernel object code\n", kcore_filename);
1515 else
1516 pr_debug("Using %s for kernel data\n", kcore_filename);
1517
1518 return 0;
1519
1520out_err:
1521 while (!list_empty(&md.maps)) {
1522 struct map_list_node *list_node;
1523
1524 list_node = list_entry(md.maps.next, struct map_list_node, node);
1525 list_del_init(&list_node->node);
1526 map__zput(list_node->map);
1527 free(list_node);
1528 }
1529 close(fd);
1530 return err;
1531}
1532
1533/*
1534 * If the kernel is relocated at boot time, kallsyms won't match. Compute the
1535 * delta based on the relocation reference symbol.
1536 */
1537static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1538{
1539 u64 addr;
1540
1541 if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1542 return 0;
1543
1544 if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1545 return -1;
1546
1547 *delta = addr - kmap->ref_reloc_sym->addr;
1548 return 0;
1549}
1550
1551int __dso__load_kallsyms(struct dso *dso, const char *filename,
1552 struct map *map, bool no_kcore)
1553{
1554 struct kmap *kmap = map__kmap(map);
1555 u64 delta = 0;
1556
1557 if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1558 return -1;
1559
1560 if (!kmap || !kmap->kmaps)
1561 return -1;
1562
1563 if (dso__load_all_kallsyms(dso, filename) < 0)
1564 return -1;
1565
1566 if (kallsyms__delta(kmap, filename, &delta))
1567 return -1;
1568
1569 symbols__fixup_end(&dso->symbols, true);
1570 symbols__fixup_duplicate(&dso->symbols);
1571
1572 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1573 dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1574 else
1575 dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1576
1577 if (!no_kcore && !dso__load_kcore(dso, map, filename))
1578 return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1579 else
1580 return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1581}
1582
1583int dso__load_kallsyms(struct dso *dso, const char *filename,
1584 struct map *map)
1585{
1586 return __dso__load_kallsyms(dso, filename, map, false);
1587}
1588
1589static int dso__load_perf_map(const char *map_path, struct dso *dso)
1590{
1591 char *line = NULL;
1592 size_t n;
1593 FILE *file;
1594 int nr_syms = 0;
1595
1596 file = fopen(map_path, "r");
1597 if (file == NULL)
1598 goto out_failure;
1599
1600 while (!feof(file)) {
1601 u64 start, size;
1602 struct symbol *sym;
1603 int line_len, len;
1604
1605 line_len = getline(&line, &n, file);
1606 if (line_len < 0)
1607 break;
1608
1609 if (!line)
1610 goto out_failure;
1611
1612 line[--line_len] = '\0'; /* \n */
1613
1614 len = hex2u64(line, &start);
1615
1616 len++;
1617 if (len + 2 >= line_len)
1618 continue;
1619
1620 len += hex2u64(line + len, &size);
1621
1622 len++;
1623 if (len + 2 >= line_len)
1624 continue;
1625
1626 sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1627
1628 if (sym == NULL)
1629 goto out_delete_line;
1630
1631 symbols__insert(&dso->symbols, sym);
1632 nr_syms++;
1633 }
1634
1635 free(line);
1636 fclose(file);
1637
1638 return nr_syms;
1639
1640out_delete_line:
1641 free(line);
1642out_failure:
1643 return -1;
1644}
1645
1646#ifdef HAVE_LIBBFD_SUPPORT
1647#define PACKAGE 'perf'
1648#include <bfd.h>
1649
1650static int bfd_symbols__cmpvalue(const void *a, const void *b)
1651{
1652 const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1653
1654 if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1655 return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1656
1657 return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1658}
1659
1660static int bfd2elf_binding(asymbol *symbol)
1661{
1662 if (symbol->flags & BSF_WEAK)
1663 return STB_WEAK;
1664 if (symbol->flags & BSF_GLOBAL)
1665 return STB_GLOBAL;
1666 if (symbol->flags & BSF_LOCAL)
1667 return STB_LOCAL;
1668 return -1;
1669}
1670
1671int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1672{
1673 int err = -1;
1674 long symbols_size, symbols_count, i;
1675 asection *section;
1676 asymbol **symbols, *sym;
1677 struct symbol *symbol;
1678 bfd *abfd;
1679 u64 start, len;
1680
1681 abfd = bfd_openr(debugfile, NULL);
1682 if (!abfd)
1683 return -1;
1684
1685 if (!bfd_check_format(abfd, bfd_object)) {
1686 pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1687 dso->long_name);
1688 goto out_close;
1689 }
1690
1691 if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1692 goto out_close;
1693
1694 symbols_size = bfd_get_symtab_upper_bound(abfd);
1695 if (symbols_size == 0) {
1696 bfd_close(abfd);
1697 return 0;
1698 }
1699
1700 if (symbols_size < 0)
1701 goto out_close;
1702
1703 symbols = malloc(symbols_size);
1704 if (!symbols)
1705 goto out_close;
1706
1707 symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1708 if (symbols_count < 0)
1709 goto out_free;
1710
1711 section = bfd_get_section_by_name(abfd, ".text");
1712 if (section) {
1713 for (i = 0; i < symbols_count; ++i) {
1714 if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
1715 !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
1716 break;
1717 }
1718 if (i < symbols_count) {
1719 /* PE symbols can only have 4 bytes, so use .text high bits */
1720 dso->text_offset = section->vma - (u32)section->vma;
1721 dso->text_offset += (u32)bfd_asymbol_value(symbols[i]);
1722 } else {
1723 dso->text_offset = section->vma - section->filepos;
1724 }
1725 }
1726
1727 qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1728
1729#ifdef bfd_get_section
1730#define bfd_asymbol_section bfd_get_section
1731#endif
1732 for (i = 0; i < symbols_count; ++i) {
1733 sym = symbols[i];
1734 section = bfd_asymbol_section(sym);
1735 if (bfd2elf_binding(sym) < 0)
1736 continue;
1737
1738 while (i + 1 < symbols_count &&
1739 bfd_asymbol_section(symbols[i + 1]) == section &&
1740 bfd2elf_binding(symbols[i + 1]) < 0)
1741 i++;
1742
1743 if (i + 1 < symbols_count &&
1744 bfd_asymbol_section(symbols[i + 1]) == section)
1745 len = symbols[i + 1]->value - sym->value;
1746 else
1747 len = section->size - sym->value;
1748
1749 start = bfd_asymbol_value(sym) - dso->text_offset;
1750 symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1751 bfd_asymbol_name(sym));
1752 if (!symbol)
1753 goto out_free;
1754
1755 symbols__insert(&dso->symbols, symbol);
1756 }
1757#ifdef bfd_get_section
1758#undef bfd_asymbol_section
1759#endif
1760
1761 symbols__fixup_end(&dso->symbols, false);
1762 symbols__fixup_duplicate(&dso->symbols);
1763 dso->adjust_symbols = 1;
1764
1765 err = 0;
1766out_free:
1767 free(symbols);
1768out_close:
1769 bfd_close(abfd);
1770 return err;
1771}
1772#endif
1773
1774static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1775 enum dso_binary_type type)
1776{
1777 switch (type) {
1778 case DSO_BINARY_TYPE__JAVA_JIT:
1779 case DSO_BINARY_TYPE__DEBUGLINK:
1780 case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1781 case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1782 case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1783 case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1784 case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1785 case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1786 return !kmod && dso->kernel == DSO_SPACE__USER;
1787
1788 case DSO_BINARY_TYPE__KALLSYMS:
1789 case DSO_BINARY_TYPE__VMLINUX:
1790 case DSO_BINARY_TYPE__KCORE:
1791 return dso->kernel == DSO_SPACE__KERNEL;
1792
1793 case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1794 case DSO_BINARY_TYPE__GUEST_VMLINUX:
1795 case DSO_BINARY_TYPE__GUEST_KCORE:
1796 return dso->kernel == DSO_SPACE__KERNEL_GUEST;
1797
1798 case DSO_BINARY_TYPE__GUEST_KMODULE:
1799 case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1800 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1801 case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1802 /*
1803 * kernel modules know their symtab type - it's set when
1804 * creating a module dso in machine__addnew_module_map().
1805 */
1806 return kmod && dso->symtab_type == type;
1807
1808 case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1809 case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1810 return true;
1811
1812 case DSO_BINARY_TYPE__BPF_PROG_INFO:
1813 case DSO_BINARY_TYPE__BPF_IMAGE:
1814 case DSO_BINARY_TYPE__OOL:
1815 case DSO_BINARY_TYPE__NOT_FOUND:
1816 default:
1817 return false;
1818 }
1819}
1820
1821/* Checks for the existence of the perf-<pid>.map file in two different
1822 * locations. First, if the process is a separate mount namespace, check in
1823 * that namespace using the pid of the innermost pid namespace. If's not in a
1824 * namespace, or the file can't be found there, try in the mount namespace of
1825 * the tracing process using our view of its pid.
1826 */
1827static int dso__find_perf_map(char *filebuf, size_t bufsz,
1828 struct nsinfo **nsip)
1829{
1830 struct nscookie nsc;
1831 struct nsinfo *nsi;
1832 struct nsinfo *nnsi;
1833 int rc = -1;
1834
1835 nsi = *nsip;
1836
1837 if (nsinfo__need_setns(nsi)) {
1838 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
1839 nsinfo__mountns_enter(nsi, &nsc);
1840 rc = access(filebuf, R_OK);
1841 nsinfo__mountns_exit(&nsc);
1842 if (rc == 0)
1843 return rc;
1844 }
1845
1846 nnsi = nsinfo__copy(nsi);
1847 if (nnsi) {
1848 nsinfo__put(nsi);
1849
1850 nsinfo__clear_need_setns(nnsi);
1851 snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
1852 *nsip = nnsi;
1853 rc = 0;
1854 }
1855
1856 return rc;
1857}
1858
1859int dso__load(struct dso *dso, struct map *map)
1860{
1861 char *name;
1862 int ret = -1;
1863 u_int i;
1864 struct machine *machine = NULL;
1865 char *root_dir = (char *) "";
1866 int ss_pos = 0;
1867 struct symsrc ss_[2];
1868 struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1869 bool kmod;
1870 bool perfmap;
1871 struct build_id bid;
1872 struct nscookie nsc;
1873 char newmapname[PATH_MAX];
1874 const char *map_path = dso->long_name;
1875
1876 mutex_lock(&dso->lock);
1877 perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
1878 if (perfmap) {
1879 if (dso->nsinfo && (dso__find_perf_map(newmapname,
1880 sizeof(newmapname), &dso->nsinfo) == 0)) {
1881 map_path = newmapname;
1882 }
1883 }
1884
1885 nsinfo__mountns_enter(dso->nsinfo, &nsc);
1886
1887 /* check again under the dso->lock */
1888 if (dso__loaded(dso)) {
1889 ret = 1;
1890 goto out;
1891 }
1892
1893 kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1894 dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1895 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1896 dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1897
1898 if (dso->kernel && !kmod) {
1899 if (dso->kernel == DSO_SPACE__KERNEL)
1900 ret = dso__load_kernel_sym(dso, map);
1901 else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
1902 ret = dso__load_guest_kernel_sym(dso, map);
1903
1904 machine = maps__machine(map__kmaps(map));
1905 if (machine__is(machine, "x86_64"))
1906 machine__map_x86_64_entry_trampolines(machine, dso);
1907 goto out;
1908 }
1909
1910 dso->adjust_symbols = 0;
1911
1912 if (perfmap) {
1913 ret = dso__load_perf_map(map_path, dso);
1914 dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1915 DSO_BINARY_TYPE__NOT_FOUND;
1916 goto out;
1917 }
1918
1919 if (machine)
1920 root_dir = machine->root_dir;
1921
1922 name = malloc(PATH_MAX);
1923 if (!name)
1924 goto out;
1925
1926 /*
1927 * Read the build id if possible. This is required for
1928 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1929 */
1930 if (!dso->has_build_id &&
1931 is_regular_file(dso->long_name)) {
1932 __symbol__join_symfs(name, PATH_MAX, dso->long_name);
1933 if (filename__read_build_id(name, &bid) > 0)
1934 dso__set_build_id(dso, &bid);
1935 }
1936
1937 /*
1938 * Iterate over candidate debug images.
1939 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1940 * and/or opd section) for processing.
1941 */
1942 for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1943 struct symsrc *ss = &ss_[ss_pos];
1944 bool next_slot = false;
1945 bool is_reg;
1946 bool nsexit;
1947 int bfdrc = -1;
1948 int sirc = -1;
1949
1950 enum dso_binary_type symtab_type = binary_type_symtab[i];
1951
1952 nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1953 symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1954
1955 if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1956 continue;
1957
1958 if (dso__read_binary_type_filename(dso, symtab_type,
1959 root_dir, name, PATH_MAX))
1960 continue;
1961
1962 if (nsexit)
1963 nsinfo__mountns_exit(&nsc);
1964
1965 is_reg = is_regular_file(name);
1966 if (!is_reg && errno == ENOENT && dso->nsinfo) {
1967 char *new_name = dso__filename_with_chroot(dso, name);
1968 if (new_name) {
1969 is_reg = is_regular_file(new_name);
1970 strlcpy(name, new_name, PATH_MAX);
1971 free(new_name);
1972 }
1973 }
1974
1975#ifdef HAVE_LIBBFD_SUPPORT
1976 if (is_reg)
1977 bfdrc = dso__load_bfd_symbols(dso, name);
1978#endif
1979 if (is_reg && bfdrc < 0)
1980 sirc = symsrc__init(ss, dso, name, symtab_type);
1981
1982 if (nsexit)
1983 nsinfo__mountns_enter(dso->nsinfo, &nsc);
1984
1985 if (bfdrc == 0) {
1986 ret = 0;
1987 break;
1988 }
1989
1990 if (!is_reg || sirc < 0)
1991 continue;
1992
1993 if (!syms_ss && symsrc__has_symtab(ss)) {
1994 syms_ss = ss;
1995 next_slot = true;
1996 if (!dso->symsrc_filename)
1997 dso->symsrc_filename = strdup(name);
1998 }
1999
2000 if (!runtime_ss && symsrc__possibly_runtime(ss)) {
2001 runtime_ss = ss;
2002 next_slot = true;
2003 }
2004
2005 if (next_slot) {
2006 ss_pos++;
2007
2008 if (syms_ss && runtime_ss)
2009 break;
2010 } else {
2011 symsrc__destroy(ss);
2012 }
2013
2014 }
2015
2016 if (!runtime_ss && !syms_ss)
2017 goto out_free;
2018
2019 if (runtime_ss && !syms_ss) {
2020 syms_ss = runtime_ss;
2021 }
2022
2023 /* We'll have to hope for the best */
2024 if (!runtime_ss && syms_ss)
2025 runtime_ss = syms_ss;
2026
2027 if (syms_ss)
2028 ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
2029 else
2030 ret = -1;
2031
2032 if (ret > 0) {
2033 int nr_plt;
2034
2035 nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
2036 if (nr_plt > 0)
2037 ret += nr_plt;
2038 }
2039
2040 for (; ss_pos > 0; ss_pos--)
2041 symsrc__destroy(&ss_[ss_pos - 1]);
2042out_free:
2043 free(name);
2044 if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
2045 ret = 0;
2046out:
2047 dso__set_loaded(dso);
2048 mutex_unlock(&dso->lock);
2049 nsinfo__mountns_exit(&nsc);
2050
2051 return ret;
2052}
2053
2054static int map__strcmp(const void *a, const void *b)
2055{
2056 const struct map *map_a = *(const struct map **)a;
2057 const struct map *map_b = *(const struct map **)b;
2058 const struct dso *dso_a = map__dso(map_a);
2059 const struct dso *dso_b = map__dso(map_b);
2060 int ret = strcmp(dso_a->short_name, dso_b->short_name);
2061
2062 if (ret == 0 && map_a != map_b) {
2063 /*
2064 * Ensure distinct but name equal maps have an order in part to
2065 * aid reference counting.
2066 */
2067 ret = (int)map__start(map_a) - (int)map__start(map_b);
2068 if (ret == 0)
2069 ret = (int)((intptr_t)map_a - (intptr_t)map_b);
2070 }
2071
2072 return ret;
2073}
2074
2075static int map__strcmp_name(const void *name, const void *b)
2076{
2077 const struct dso *dso = map__dso(*(const struct map **)b);
2078
2079 return strcmp(name, dso->short_name);
2080}
2081
2082void __maps__sort_by_name(struct maps *maps)
2083{
2084 qsort(maps__maps_by_name(maps), maps__nr_maps(maps), sizeof(struct map *), map__strcmp);
2085}
2086
2087static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
2088{
2089 struct map_rb_node *rb_node;
2090 struct map **maps_by_name = realloc(maps__maps_by_name(maps),
2091 maps__nr_maps(maps) * sizeof(struct map *));
2092 int i = 0;
2093
2094 if (maps_by_name == NULL)
2095 return -1;
2096
2097 up_read(maps__lock(maps));
2098 down_write(maps__lock(maps));
2099
2100 RC_CHK_ACCESS(maps)->maps_by_name = maps_by_name;
2101 RC_CHK_ACCESS(maps)->nr_maps_allocated = maps__nr_maps(maps);
2102
2103 maps__for_each_entry(maps, rb_node)
2104 maps_by_name[i++] = map__get(rb_node->map);
2105
2106 __maps__sort_by_name(maps);
2107
2108 up_write(maps__lock(maps));
2109 down_read(maps__lock(maps));
2110
2111 return 0;
2112}
2113
2114static struct map *__maps__find_by_name(struct maps *maps, const char *name)
2115{
2116 struct map **mapp;
2117
2118 if (maps__maps_by_name(maps) == NULL &&
2119 map__groups__sort_by_name_from_rbtree(maps))
2120 return NULL;
2121
2122 mapp = bsearch(name, maps__maps_by_name(maps), maps__nr_maps(maps),
2123 sizeof(*mapp), map__strcmp_name);
2124 if (mapp)
2125 return *mapp;
2126 return NULL;
2127}
2128
2129struct map *maps__find_by_name(struct maps *maps, const char *name)
2130{
2131 struct map_rb_node *rb_node;
2132 struct map *map;
2133
2134 down_read(maps__lock(maps));
2135
2136
2137 if (RC_CHK_ACCESS(maps)->last_search_by_name) {
2138 const struct dso *dso = map__dso(RC_CHK_ACCESS(maps)->last_search_by_name);
2139
2140 if (strcmp(dso->short_name, name) == 0) {
2141 map = RC_CHK_ACCESS(maps)->last_search_by_name;
2142 goto out_unlock;
2143 }
2144 }
2145 /*
2146 * If we have maps->maps_by_name, then the name isn't in the rbtree,
2147 * as maps->maps_by_name mirrors the rbtree when lookups by name are
2148 * made.
2149 */
2150 map = __maps__find_by_name(maps, name);
2151 if (map || maps__maps_by_name(maps) != NULL)
2152 goto out_unlock;
2153
2154 /* Fallback to traversing the rbtree... */
2155 maps__for_each_entry(maps, rb_node) {
2156 struct dso *dso;
2157
2158 map = rb_node->map;
2159 dso = map__dso(map);
2160 if (strcmp(dso->short_name, name) == 0) {
2161 RC_CHK_ACCESS(maps)->last_search_by_name = map;
2162 goto out_unlock;
2163 }
2164 }
2165 map = NULL;
2166
2167out_unlock:
2168 up_read(maps__lock(maps));
2169 return map;
2170}
2171
2172int dso__load_vmlinux(struct dso *dso, struct map *map,
2173 const char *vmlinux, bool vmlinux_allocated)
2174{
2175 int err = -1;
2176 struct symsrc ss;
2177 char symfs_vmlinux[PATH_MAX];
2178 enum dso_binary_type symtab_type;
2179
2180 if (vmlinux[0] == '/')
2181 snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
2182 else
2183 symbol__join_symfs(symfs_vmlinux, vmlinux);
2184
2185 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2186 symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2187 else
2188 symtab_type = DSO_BINARY_TYPE__VMLINUX;
2189
2190 if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
2191 return -1;
2192
2193 err = dso__load_sym(dso, map, &ss, &ss, 0);
2194 symsrc__destroy(&ss);
2195
2196 if (err > 0) {
2197 if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
2198 dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2199 else
2200 dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
2201 dso__set_long_name(dso, vmlinux, vmlinux_allocated);
2202 dso__set_loaded(dso);
2203 pr_debug("Using %s for symbols\n", symfs_vmlinux);
2204 }
2205
2206 return err;
2207}
2208
2209int dso__load_vmlinux_path(struct dso *dso, struct map *map)
2210{
2211 int i, err = 0;
2212 char *filename = NULL;
2213
2214 pr_debug("Looking at the vmlinux_path (%d entries long)\n",
2215 vmlinux_path__nr_entries + 1);
2216
2217 for (i = 0; i < vmlinux_path__nr_entries; ++i) {
2218 err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
2219 if (err > 0)
2220 goto out;
2221 }
2222
2223 if (!symbol_conf.ignore_vmlinux_buildid)
2224 filename = dso__build_id_filename(dso, NULL, 0, false);
2225 if (filename != NULL) {
2226 err = dso__load_vmlinux(dso, map, filename, true);
2227 if (err > 0)
2228 goto out;
2229 free(filename);
2230 }
2231out:
2232 return err;
2233}
2234
2235static bool visible_dir_filter(const char *name, struct dirent *d)
2236{
2237 if (d->d_type != DT_DIR)
2238 return false;
2239 return lsdir_no_dot_filter(name, d);
2240}
2241
2242static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2243{
2244 char kallsyms_filename[PATH_MAX];
2245 int ret = -1;
2246 struct strlist *dirs;
2247 struct str_node *nd;
2248
2249 dirs = lsdir(dir, visible_dir_filter);
2250 if (!dirs)
2251 return -1;
2252
2253 strlist__for_each_entry(nd, dirs) {
2254 scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2255 "%s/%s/kallsyms", dir, nd->s);
2256 if (!validate_kcore_addresses(kallsyms_filename, map)) {
2257 strlcpy(dir, kallsyms_filename, dir_sz);
2258 ret = 0;
2259 break;
2260 }
2261 }
2262
2263 strlist__delete(dirs);
2264
2265 return ret;
2266}
2267
2268/*
2269 * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2270 * since access(R_OK) only checks with real UID/GID but open() use effective
2271 * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2272 */
2273static bool filename__readable(const char *file)
2274{
2275 int fd = open(file, O_RDONLY);
2276 if (fd < 0)
2277 return false;
2278 close(fd);
2279 return true;
2280}
2281
2282static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2283{
2284 struct build_id bid;
2285 char sbuild_id[SBUILD_ID_SIZE];
2286 bool is_host = false;
2287 char path[PATH_MAX];
2288
2289 if (!dso->has_build_id) {
2290 /*
2291 * Last resort, if we don't have a build-id and couldn't find
2292 * any vmlinux file, try the running kernel kallsyms table.
2293 */
2294 goto proc_kallsyms;
2295 }
2296
2297 if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2298 is_host = dso__build_id_equal(dso, &bid);
2299
2300 /* Try a fast path for /proc/kallsyms if possible */
2301 if (is_host) {
2302 /*
2303 * Do not check the build-id cache, unless we know we cannot use
2304 * /proc/kcore or module maps don't match to /proc/kallsyms.
2305 * To check readability of /proc/kcore, do not use access(R_OK)
2306 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2307 * can't check it.
2308 */
2309 if (filename__readable("/proc/kcore") &&
2310 !validate_kcore_addresses("/proc/kallsyms", map))
2311 goto proc_kallsyms;
2312 }
2313
2314 build_id__sprintf(&dso->bid, sbuild_id);
2315
2316 /* Find kallsyms in build-id cache with kcore */
2317 scnprintf(path, sizeof(path), "%s/%s/%s",
2318 buildid_dir, DSO__NAME_KCORE, sbuild_id);
2319
2320 if (!find_matching_kcore(map, path, sizeof(path)))
2321 return strdup(path);
2322
2323 /* Use current /proc/kallsyms if possible */
2324 if (is_host) {
2325proc_kallsyms:
2326 return strdup("/proc/kallsyms");
2327 }
2328
2329 /* Finally, find a cache of kallsyms */
2330 if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2331 pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2332 sbuild_id);
2333 return NULL;
2334 }
2335
2336 return strdup(path);
2337}
2338
2339static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2340{
2341 int err;
2342 const char *kallsyms_filename = NULL;
2343 char *kallsyms_allocated_filename = NULL;
2344 char *filename = NULL;
2345
2346 /*
2347 * Step 1: if the user specified a kallsyms or vmlinux filename, use
2348 * it and only it, reporting errors to the user if it cannot be used.
2349 *
2350 * For instance, try to analyse an ARM perf.data file _without_ a
2351 * build-id, or if the user specifies the wrong path to the right
2352 * vmlinux file, obviously we can't fallback to another vmlinux (a
2353 * x86_86 one, on the machine where analysis is being performed, say),
2354 * or worse, /proc/kallsyms.
2355 *
2356 * If the specified file _has_ a build-id and there is a build-id
2357 * section in the perf.data file, we will still do the expected
2358 * validation in dso__load_vmlinux and will bail out if they don't
2359 * match.
2360 */
2361 if (symbol_conf.kallsyms_name != NULL) {
2362 kallsyms_filename = symbol_conf.kallsyms_name;
2363 goto do_kallsyms;
2364 }
2365
2366 if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2367 return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2368 }
2369
2370 /*
2371 * Before checking on common vmlinux locations, check if it's
2372 * stored as standard build id binary (not kallsyms) under
2373 * .debug cache.
2374 */
2375 if (!symbol_conf.ignore_vmlinux_buildid)
2376 filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2377 if (filename != NULL) {
2378 err = dso__load_vmlinux(dso, map, filename, true);
2379 if (err > 0)
2380 return err;
2381 free(filename);
2382 }
2383
2384 if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2385 err = dso__load_vmlinux_path(dso, map);
2386 if (err > 0)
2387 return err;
2388 }
2389
2390 /* do not try local files if a symfs was given */
2391 if (symbol_conf.symfs[0] != 0)
2392 return -1;
2393
2394 kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2395 if (!kallsyms_allocated_filename)
2396 return -1;
2397
2398 kallsyms_filename = kallsyms_allocated_filename;
2399
2400do_kallsyms:
2401 err = dso__load_kallsyms(dso, kallsyms_filename, map);
2402 if (err > 0)
2403 pr_debug("Using %s for symbols\n", kallsyms_filename);
2404 free(kallsyms_allocated_filename);
2405
2406 if (err > 0 && !dso__is_kcore(dso)) {
2407 dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
2408 dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2409 map__fixup_start(map);
2410 map__fixup_end(map);
2411 }
2412
2413 return err;
2414}
2415
2416static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2417{
2418 int err;
2419 const char *kallsyms_filename;
2420 struct machine *machine = maps__machine(map__kmaps(map));
2421 char path[PATH_MAX];
2422
2423 if (machine->kallsyms_filename) {
2424 kallsyms_filename = machine->kallsyms_filename;
2425 } else if (machine__is_default_guest(machine)) {
2426 /*
2427 * if the user specified a vmlinux filename, use it and only
2428 * it, reporting errors to the user if it cannot be used.
2429 * Or use file guest_kallsyms inputted by user on commandline
2430 */
2431 if (symbol_conf.default_guest_vmlinux_name != NULL) {
2432 err = dso__load_vmlinux(dso, map,
2433 symbol_conf.default_guest_vmlinux_name,
2434 false);
2435 return err;
2436 }
2437
2438 kallsyms_filename = symbol_conf.default_guest_kallsyms;
2439 if (!kallsyms_filename)
2440 return -1;
2441 } else {
2442 sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2443 kallsyms_filename = path;
2444 }
2445
2446 err = dso__load_kallsyms(dso, kallsyms_filename, map);
2447 if (err > 0)
2448 pr_debug("Using %s for symbols\n", kallsyms_filename);
2449 if (err > 0 && !dso__is_kcore(dso)) {
2450 dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
2451 dso__set_long_name(dso, machine->mmap_name, false);
2452 map__fixup_start(map);
2453 map__fixup_end(map);
2454 }
2455
2456 return err;
2457}
2458
2459static void vmlinux_path__exit(void)
2460{
2461 while (--vmlinux_path__nr_entries >= 0)
2462 zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2463 vmlinux_path__nr_entries = 0;
2464
2465 zfree(&vmlinux_path);
2466}
2467
2468static const char * const vmlinux_paths[] = {
2469 "vmlinux",
2470 "/boot/vmlinux"
2471};
2472
2473static const char * const vmlinux_paths_upd[] = {
2474 "/boot/vmlinux-%s",
2475 "/usr/lib/debug/boot/vmlinux-%s",
2476 "/lib/modules/%s/build/vmlinux",
2477 "/usr/lib/debug/lib/modules/%s/vmlinux",
2478 "/usr/lib/debug/boot/vmlinux-%s.debug"
2479};
2480
2481static int vmlinux_path__add(const char *new_entry)
2482{
2483 vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2484 if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2485 return -1;
2486 ++vmlinux_path__nr_entries;
2487
2488 return 0;
2489}
2490
2491static int vmlinux_path__init(struct perf_env *env)
2492{
2493 struct utsname uts;
2494 char bf[PATH_MAX];
2495 char *kernel_version;
2496 unsigned int i;
2497
2498 vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2499 ARRAY_SIZE(vmlinux_paths_upd)));
2500 if (vmlinux_path == NULL)
2501 return -1;
2502
2503 for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2504 if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2505 goto out_fail;
2506
2507 /* only try kernel version if no symfs was given */
2508 if (symbol_conf.symfs[0] != 0)
2509 return 0;
2510
2511 if (env) {
2512 kernel_version = env->os_release;
2513 } else {
2514 if (uname(&uts) < 0)
2515 goto out_fail;
2516
2517 kernel_version = uts.release;
2518 }
2519
2520 for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2521 snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2522 if (vmlinux_path__add(bf) < 0)
2523 goto out_fail;
2524 }
2525
2526 return 0;
2527
2528out_fail:
2529 vmlinux_path__exit();
2530 return -1;
2531}
2532
2533int setup_list(struct strlist **list, const char *list_str,
2534 const char *list_name)
2535{
2536 if (list_str == NULL)
2537 return 0;
2538
2539 *list = strlist__new(list_str, NULL);
2540 if (!*list) {
2541 pr_err("problems parsing %s list\n", list_name);
2542 return -1;
2543 }
2544
2545 symbol_conf.has_filter = true;
2546 return 0;
2547}
2548
2549int setup_intlist(struct intlist **list, const char *list_str,
2550 const char *list_name)
2551{
2552 if (list_str == NULL)
2553 return 0;
2554
2555 *list = intlist__new(list_str);
2556 if (!*list) {
2557 pr_err("problems parsing %s list\n", list_name);
2558 return -1;
2559 }
2560 return 0;
2561}
2562
2563static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
2564{
2565 struct str_node *pos, *tmp;
2566 unsigned long val;
2567 char *sep;
2568 const char *end;
2569 int i = 0, err;
2570
2571 *addr_list = intlist__new(NULL);
2572 if (!*addr_list)
2573 return -1;
2574
2575 strlist__for_each_entry_safe(pos, tmp, sym_list) {
2576 errno = 0;
2577 val = strtoul(pos->s, &sep, 16);
2578 if (errno || (sep == pos->s))
2579 continue;
2580
2581 if (*sep != '\0') {
2582 end = pos->s + strlen(pos->s) - 1;
2583 while (end >= sep && isspace(*end))
2584 end--;
2585
2586 if (end >= sep)
2587 continue;
2588 }
2589
2590 err = intlist__add(*addr_list, val);
2591 if (err)
2592 break;
2593
2594 strlist__remove(sym_list, pos);
2595 i++;
2596 }
2597
2598 if (i == 0) {
2599 intlist__delete(*addr_list);
2600 *addr_list = NULL;
2601 }
2602
2603 return 0;
2604}
2605
2606static bool symbol__read_kptr_restrict(void)
2607{
2608 bool value = false;
2609 FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2610
2611 if (fp != NULL) {
2612 char line[8];
2613
2614 if (fgets(line, sizeof(line), fp) != NULL)
2615 value = perf_cap__capable(CAP_SYSLOG) ?
2616 (atoi(line) >= 2) :
2617 (atoi(line) != 0);
2618
2619 fclose(fp);
2620 }
2621
2622 /* Per kernel/kallsyms.c:
2623 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2624 */
2625 if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
2626 value = true;
2627
2628 return value;
2629}
2630
2631int symbol__annotation_init(void)
2632{
2633 if (symbol_conf.init_annotation)
2634 return 0;
2635
2636 if (symbol_conf.initialized) {
2637 pr_err("Annotation needs to be init before symbol__init()\n");
2638 return -1;
2639 }
2640
2641 symbol_conf.priv_size += sizeof(struct annotation);
2642 symbol_conf.init_annotation = true;
2643 return 0;
2644}
2645
2646int symbol__init(struct perf_env *env)
2647{
2648 const char *symfs;
2649
2650 if (symbol_conf.initialized)
2651 return 0;
2652
2653 symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2654
2655 symbol__elf_init();
2656
2657 if (symbol_conf.sort_by_name)
2658 symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
2659 sizeof(struct symbol));
2660
2661 if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2662 return -1;
2663
2664 if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2665 pr_err("'.' is the only non valid --field-separator argument\n");
2666 return -1;
2667 }
2668
2669 if (setup_list(&symbol_conf.dso_list,
2670 symbol_conf.dso_list_str, "dso") < 0)
2671 return -1;
2672
2673 if (setup_list(&symbol_conf.comm_list,
2674 symbol_conf.comm_list_str, "comm") < 0)
2675 goto out_free_dso_list;
2676
2677 if (setup_intlist(&symbol_conf.pid_list,
2678 symbol_conf.pid_list_str, "pid") < 0)
2679 goto out_free_comm_list;
2680
2681 if (setup_intlist(&symbol_conf.tid_list,
2682 symbol_conf.tid_list_str, "tid") < 0)
2683 goto out_free_pid_list;
2684
2685 if (setup_list(&symbol_conf.sym_list,
2686 symbol_conf.sym_list_str, "symbol") < 0)
2687 goto out_free_tid_list;
2688
2689 if (symbol_conf.sym_list &&
2690 setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
2691 goto out_free_sym_list;
2692
2693 if (setup_list(&symbol_conf.bt_stop_list,
2694 symbol_conf.bt_stop_list_str, "symbol") < 0)
2695 goto out_free_sym_list;
2696
2697 /*
2698 * A path to symbols of "/" is identical to ""
2699 * reset here for simplicity.
2700 */
2701 symfs = realpath(symbol_conf.symfs, NULL);
2702 if (symfs == NULL)
2703 symfs = symbol_conf.symfs;
2704 if (strcmp(symfs, "/") == 0)
2705 symbol_conf.symfs = "";
2706 if (symfs != symbol_conf.symfs)
2707 free((void *)symfs);
2708
2709 symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2710
2711 symbol_conf.initialized = true;
2712 return 0;
2713
2714out_free_sym_list:
2715 strlist__delete(symbol_conf.sym_list);
2716 intlist__delete(symbol_conf.addr_list);
2717out_free_tid_list:
2718 intlist__delete(symbol_conf.tid_list);
2719out_free_pid_list:
2720 intlist__delete(symbol_conf.pid_list);
2721out_free_comm_list:
2722 strlist__delete(symbol_conf.comm_list);
2723out_free_dso_list:
2724 strlist__delete(symbol_conf.dso_list);
2725 return -1;
2726}
2727
2728void symbol__exit(void)
2729{
2730 if (!symbol_conf.initialized)
2731 return;
2732 strlist__delete(symbol_conf.bt_stop_list);
2733 strlist__delete(symbol_conf.sym_list);
2734 strlist__delete(symbol_conf.dso_list);
2735 strlist__delete(symbol_conf.comm_list);
2736 intlist__delete(symbol_conf.tid_list);
2737 intlist__delete(symbol_conf.pid_list);
2738 intlist__delete(symbol_conf.addr_list);
2739 vmlinux_path__exit();
2740 symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2741 symbol_conf.bt_stop_list = NULL;
2742 symbol_conf.initialized = false;
2743}
2744
2745int symbol__config_symfs(const struct option *opt __maybe_unused,
2746 const char *dir, int unset __maybe_unused)
2747{
2748 char *bf = NULL;
2749 int ret;
2750
2751 symbol_conf.symfs = strdup(dir);
2752 if (symbol_conf.symfs == NULL)
2753 return -ENOMEM;
2754
2755 /* skip the locally configured cache if a symfs is given, and
2756 * config buildid dir to symfs/.debug
2757 */
2758 ret = asprintf(&bf, "%s/%s", dir, ".debug");
2759 if (ret < 0)
2760 return -ENOMEM;
2761
2762 set_buildid_dir(bf);
2763
2764 free(bf);
2765 return 0;
2766}
2767
2768struct mem_info *mem_info__get(struct mem_info *mi)
2769{
2770 if (mi)
2771 refcount_inc(&mi->refcnt);
2772 return mi;
2773}
2774
2775void mem_info__put(struct mem_info *mi)
2776{
2777 if (mi && refcount_dec_and_test(&mi->refcnt))
2778 free(mi);
2779}
2780
2781struct mem_info *mem_info__new(void)
2782{
2783 struct mem_info *mi = zalloc(sizeof(*mi));
2784
2785 if (mi)
2786 refcount_set(&mi->refcnt, 1);
2787 return mi;
2788}
2789
2790/*
2791 * Checks that user supplied symbol kernel files are accessible because
2792 * the default mechanism for accessing elf files fails silently. i.e. if
2793 * debug syms for a build ID aren't found perf carries on normally. When
2794 * they are user supplied we should assume that the user doesn't want to
2795 * silently fail.
2796 */
2797int symbol__validate_sym_arguments(void)
2798{
2799 if (symbol_conf.vmlinux_name &&
2800 access(symbol_conf.vmlinux_name, R_OK)) {
2801 pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
2802 return -EINVAL;
2803 }
2804 if (symbol_conf.kallsyms_name &&
2805 access(symbol_conf.kallsyms_name, R_OK)) {
2806 pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
2807 return -EINVAL;
2808 }
2809 return 0;
2810}