xref: /linux/tools/perf/util/symbol.c (revision 0883c2c06fb5bcf5b9e008270827e63c09a88c1e)
1 #include <dirent.h>
2 #include <errno.h>
3 #include <stdlib.h>
4 #include <stdio.h>
5 #include <string.h>
6 #include <sys/types.h>
7 #include <sys/stat.h>
8 #include <sys/param.h>
9 #include <fcntl.h>
10 #include <unistd.h>
11 #include <inttypes.h>
12 #include "build-id.h"
13 #include "util.h"
14 #include "debug.h"
15 #include "machine.h"
16 #include "symbol.h"
17 #include "strlist.h"
18 #include "intlist.h"
19 #include "header.h"
20 
21 #include <elf.h>
22 #include <limits.h>
23 #include <symbol/kallsyms.h>
24 #include <sys/utsname.h>
25 
26 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
27 				symbol_filter_t filter);
28 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
29 			symbol_filter_t filter);
30 int vmlinux_path__nr_entries;
31 char **vmlinux_path;
32 
33 struct symbol_conf symbol_conf = {
34 	.use_modules		= true,
35 	.try_vmlinux_path	= true,
36 	.annotate_src		= true,
37 	.demangle		= true,
38 	.demangle_kernel	= false,
39 	.cumulate_callchain	= true,
40 	.show_hist_headers	= true,
41 	.symfs			= "",
42 	.event_group		= true,
43 };
44 
45 static enum dso_binary_type binary_type_symtab[] = {
46 	DSO_BINARY_TYPE__KALLSYMS,
47 	DSO_BINARY_TYPE__GUEST_KALLSYMS,
48 	DSO_BINARY_TYPE__JAVA_JIT,
49 	DSO_BINARY_TYPE__DEBUGLINK,
50 	DSO_BINARY_TYPE__BUILD_ID_CACHE,
51 	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
52 	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
53 	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
54 	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
55 	DSO_BINARY_TYPE__GUEST_KMODULE,
56 	DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
57 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
58 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
59 	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
60 	DSO_BINARY_TYPE__NOT_FOUND,
61 };
62 
63 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
64 
65 bool symbol_type__is_a(char symbol_type, enum map_type map_type)
66 {
67 	symbol_type = toupper(symbol_type);
68 
69 	switch (map_type) {
70 	case MAP__FUNCTION:
71 		return symbol_type == 'T' || symbol_type == 'W';
72 	case MAP__VARIABLE:
73 		return symbol_type == 'D';
74 	default:
75 		return false;
76 	}
77 }
78 
79 static int prefix_underscores_count(const char *str)
80 {
81 	const char *tail = str;
82 
83 	while (*tail == '_')
84 		tail++;
85 
86 	return tail - str;
87 }
88 
89 int __weak arch__choose_best_symbol(struct symbol *syma,
90 				    struct symbol *symb __maybe_unused)
91 {
92 	/* Avoid "SyS" kernel syscall aliases */
93 	if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
94 		return SYMBOL_B;
95 	if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
96 		return SYMBOL_B;
97 
98 	return SYMBOL_A;
99 }
100 
101 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
102 {
103 	s64 a;
104 	s64 b;
105 	size_t na, nb;
106 
107 	/* Prefer a symbol with non zero length */
108 	a = syma->end - syma->start;
109 	b = symb->end - symb->start;
110 	if ((b == 0) && (a > 0))
111 		return SYMBOL_A;
112 	else if ((a == 0) && (b > 0))
113 		return SYMBOL_B;
114 
115 	/* Prefer a non weak symbol over a weak one */
116 	a = syma->binding == STB_WEAK;
117 	b = symb->binding == STB_WEAK;
118 	if (b && !a)
119 		return SYMBOL_A;
120 	if (a && !b)
121 		return SYMBOL_B;
122 
123 	/* Prefer a global symbol over a non global one */
124 	a = syma->binding == STB_GLOBAL;
125 	b = symb->binding == STB_GLOBAL;
126 	if (a && !b)
127 		return SYMBOL_A;
128 	if (b && !a)
129 		return SYMBOL_B;
130 
131 	/* Prefer a symbol with less underscores */
132 	a = prefix_underscores_count(syma->name);
133 	b = prefix_underscores_count(symb->name);
134 	if (b > a)
135 		return SYMBOL_A;
136 	else if (a > b)
137 		return SYMBOL_B;
138 
139 	/* Choose the symbol with the longest name */
140 	na = strlen(syma->name);
141 	nb = strlen(symb->name);
142 	if (na > nb)
143 		return SYMBOL_A;
144 	else if (na < nb)
145 		return SYMBOL_B;
146 
147 	return arch__choose_best_symbol(syma, symb);
148 }
149 
150 void symbols__fixup_duplicate(struct rb_root *symbols)
151 {
152 	struct rb_node *nd;
153 	struct symbol *curr, *next;
154 
155 	nd = rb_first(symbols);
156 
157 	while (nd) {
158 		curr = rb_entry(nd, struct symbol, rb_node);
159 again:
160 		nd = rb_next(&curr->rb_node);
161 		next = rb_entry(nd, struct symbol, rb_node);
162 
163 		if (!nd)
164 			break;
165 
166 		if (curr->start != next->start)
167 			continue;
168 
169 		if (choose_best_symbol(curr, next) == SYMBOL_A) {
170 			rb_erase(&next->rb_node, symbols);
171 			symbol__delete(next);
172 			goto again;
173 		} else {
174 			nd = rb_next(&curr->rb_node);
175 			rb_erase(&curr->rb_node, symbols);
176 			symbol__delete(curr);
177 		}
178 	}
179 }
180 
181 void symbols__fixup_end(struct rb_root *symbols)
182 {
183 	struct rb_node *nd, *prevnd = rb_first(symbols);
184 	struct symbol *curr, *prev;
185 
186 	if (prevnd == NULL)
187 		return;
188 
189 	curr = rb_entry(prevnd, struct symbol, rb_node);
190 
191 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
192 		prev = curr;
193 		curr = rb_entry(nd, struct symbol, rb_node);
194 
195 		if (prev->end == prev->start && prev->end != curr->start)
196 			prev->end = curr->start;
197 	}
198 
199 	/* Last entry */
200 	if (curr->end == curr->start)
201 		curr->end = roundup(curr->start, 4096);
202 }
203 
204 void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
205 {
206 	struct maps *maps = &mg->maps[type];
207 	struct map *next, *curr;
208 
209 	pthread_rwlock_wrlock(&maps->lock);
210 
211 	curr = maps__first(maps);
212 	if (curr == NULL)
213 		goto out_unlock;
214 
215 	for (next = map__next(curr); next; next = map__next(curr)) {
216 		curr->end = next->start;
217 		curr = next;
218 	}
219 
220 	/*
221 	 * We still haven't the actual symbols, so guess the
222 	 * last map final address.
223 	 */
224 	curr->end = ~0ULL;
225 
226 out_unlock:
227 	pthread_rwlock_unlock(&maps->lock);
228 }
229 
230 struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
231 {
232 	size_t namelen = strlen(name) + 1;
233 	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
234 					sizeof(*sym) + namelen));
235 	if (sym == NULL)
236 		return NULL;
237 
238 	if (symbol_conf.priv_size)
239 		sym = ((void *)sym) + symbol_conf.priv_size;
240 
241 	sym->start   = start;
242 	sym->end     = len ? start + len : start;
243 	sym->binding = binding;
244 	sym->namelen = namelen - 1;
245 
246 	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
247 		  __func__, name, start, sym->end);
248 	memcpy(sym->name, name, namelen);
249 
250 	return sym;
251 }
252 
253 void symbol__delete(struct symbol *sym)
254 {
255 	free(((void *)sym) - symbol_conf.priv_size);
256 }
257 
258 void symbols__delete(struct rb_root *symbols)
259 {
260 	struct symbol *pos;
261 	struct rb_node *next = rb_first(symbols);
262 
263 	while (next) {
264 		pos = rb_entry(next, struct symbol, rb_node);
265 		next = rb_next(&pos->rb_node);
266 		rb_erase(&pos->rb_node, symbols);
267 		symbol__delete(pos);
268 	}
269 }
270 
271 void symbols__insert(struct rb_root *symbols, struct symbol *sym)
272 {
273 	struct rb_node **p = &symbols->rb_node;
274 	struct rb_node *parent = NULL;
275 	const u64 ip = sym->start;
276 	struct symbol *s;
277 
278 	while (*p != NULL) {
279 		parent = *p;
280 		s = rb_entry(parent, struct symbol, rb_node);
281 		if (ip < s->start)
282 			p = &(*p)->rb_left;
283 		else
284 			p = &(*p)->rb_right;
285 	}
286 	rb_link_node(&sym->rb_node, parent, p);
287 	rb_insert_color(&sym->rb_node, symbols);
288 }
289 
290 static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
291 {
292 	struct rb_node *n;
293 
294 	if (symbols == NULL)
295 		return NULL;
296 
297 	n = symbols->rb_node;
298 
299 	while (n) {
300 		struct symbol *s = rb_entry(n, struct symbol, rb_node);
301 
302 		if (ip < s->start)
303 			n = n->rb_left;
304 		else if (ip > s->end || (ip == s->end && ip != s->start))
305 			n = n->rb_right;
306 		else
307 			return s;
308 	}
309 
310 	return NULL;
311 }
312 
313 static struct symbol *symbols__first(struct rb_root *symbols)
314 {
315 	struct rb_node *n = rb_first(symbols);
316 
317 	if (n)
318 		return rb_entry(n, struct symbol, rb_node);
319 
320 	return NULL;
321 }
322 
323 static struct symbol *symbols__next(struct symbol *sym)
324 {
325 	struct rb_node *n = rb_next(&sym->rb_node);
326 
327 	if (n)
328 		return rb_entry(n, struct symbol, rb_node);
329 
330 	return NULL;
331 }
332 
333 static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
334 {
335 	struct rb_node **p = &symbols->rb_node;
336 	struct rb_node *parent = NULL;
337 	struct symbol_name_rb_node *symn, *s;
338 
339 	symn = container_of(sym, struct symbol_name_rb_node, sym);
340 
341 	while (*p != NULL) {
342 		parent = *p;
343 		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
344 		if (strcmp(sym->name, s->sym.name) < 0)
345 			p = &(*p)->rb_left;
346 		else
347 			p = &(*p)->rb_right;
348 	}
349 	rb_link_node(&symn->rb_node, parent, p);
350 	rb_insert_color(&symn->rb_node, symbols);
351 }
352 
353 static void symbols__sort_by_name(struct rb_root *symbols,
354 				  struct rb_root *source)
355 {
356 	struct rb_node *nd;
357 
358 	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
359 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
360 		symbols__insert_by_name(symbols, pos);
361 	}
362 }
363 
364 static struct symbol *symbols__find_by_name(struct rb_root *symbols,
365 					    const char *name)
366 {
367 	struct rb_node *n;
368 	struct symbol_name_rb_node *s = NULL;
369 
370 	if (symbols == NULL)
371 		return NULL;
372 
373 	n = symbols->rb_node;
374 
375 	while (n) {
376 		int cmp;
377 
378 		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
379 		cmp = arch__compare_symbol_names(name, s->sym.name);
380 
381 		if (cmp < 0)
382 			n = n->rb_left;
383 		else if (cmp > 0)
384 			n = n->rb_right;
385 		else
386 			break;
387 	}
388 
389 	if (n == NULL)
390 		return NULL;
391 
392 	/* return first symbol that has same name (if any) */
393 	for (n = rb_prev(n); n; n = rb_prev(n)) {
394 		struct symbol_name_rb_node *tmp;
395 
396 		tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
397 		if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
398 			break;
399 
400 		s = tmp;
401 	}
402 
403 	return &s->sym;
404 }
405 
406 void dso__reset_find_symbol_cache(struct dso *dso)
407 {
408 	enum map_type type;
409 
410 	for (type = MAP__FUNCTION; type <= MAP__VARIABLE; ++type) {
411 		dso->last_find_result[type].addr   = 0;
412 		dso->last_find_result[type].symbol = NULL;
413 	}
414 }
415 
416 void dso__insert_symbol(struct dso *dso, enum map_type type, struct symbol *sym)
417 {
418 	symbols__insert(&dso->symbols[type], sym);
419 
420 	/* update the symbol cache if necessary */
421 	if (dso->last_find_result[type].addr >= sym->start &&
422 	    (dso->last_find_result[type].addr < sym->end ||
423 	    sym->start == sym->end)) {
424 		dso->last_find_result[type].symbol = sym;
425 	}
426 }
427 
428 struct symbol *dso__find_symbol(struct dso *dso,
429 				enum map_type type, u64 addr)
430 {
431 	if (dso->last_find_result[type].addr != addr) {
432 		dso->last_find_result[type].addr   = addr;
433 		dso->last_find_result[type].symbol = symbols__find(&dso->symbols[type], addr);
434 	}
435 
436 	return dso->last_find_result[type].symbol;
437 }
438 
439 struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
440 {
441 	return symbols__first(&dso->symbols[type]);
442 }
443 
444 struct symbol *dso__next_symbol(struct symbol *sym)
445 {
446 	return symbols__next(sym);
447 }
448 
449 struct symbol *symbol__next_by_name(struct symbol *sym)
450 {
451 	struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
452 	struct rb_node *n = rb_next(&s->rb_node);
453 
454 	return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
455 }
456 
457  /*
458   * Teturns first symbol that matched with @name.
459   */
460 struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
461 					const char *name)
462 {
463 	return symbols__find_by_name(&dso->symbol_names[type], name);
464 }
465 
466 void dso__sort_by_name(struct dso *dso, enum map_type type)
467 {
468 	dso__set_sorted_by_name(dso, type);
469 	return symbols__sort_by_name(&dso->symbol_names[type],
470 				     &dso->symbols[type]);
471 }
472 
473 int modules__parse(const char *filename, void *arg,
474 		   int (*process_module)(void *arg, const char *name,
475 					 u64 start))
476 {
477 	char *line = NULL;
478 	size_t n;
479 	FILE *file;
480 	int err = 0;
481 
482 	file = fopen(filename, "r");
483 	if (file == NULL)
484 		return -1;
485 
486 	while (1) {
487 		char name[PATH_MAX];
488 		u64 start;
489 		char *sep;
490 		ssize_t line_len;
491 
492 		line_len = getline(&line, &n, file);
493 		if (line_len < 0) {
494 			if (feof(file))
495 				break;
496 			err = -1;
497 			goto out;
498 		}
499 
500 		if (!line) {
501 			err = -1;
502 			goto out;
503 		}
504 
505 		line[--line_len] = '\0'; /* \n */
506 
507 		sep = strrchr(line, 'x');
508 		if (sep == NULL)
509 			continue;
510 
511 		hex2u64(sep + 1, &start);
512 
513 		sep = strchr(line, ' ');
514 		if (sep == NULL)
515 			continue;
516 
517 		*sep = '\0';
518 
519 		scnprintf(name, sizeof(name), "[%s]", line);
520 
521 		err = process_module(arg, name, start);
522 		if (err)
523 			break;
524 	}
525 out:
526 	free(line);
527 	fclose(file);
528 	return err;
529 }
530 
531 struct process_kallsyms_args {
532 	struct map *map;
533 	struct dso *dso;
534 };
535 
536 /*
537  * These are symbols in the kernel image, so make sure that
538  * sym is from a kernel DSO.
539  */
540 bool symbol__is_idle(struct symbol *sym)
541 {
542 	const char * const idle_symbols[] = {
543 		"cpu_idle",
544 		"cpu_startup_entry",
545 		"intel_idle",
546 		"default_idle",
547 		"native_safe_halt",
548 		"enter_idle",
549 		"exit_idle",
550 		"mwait_idle",
551 		"mwait_idle_with_hints",
552 		"poll_idle",
553 		"ppc64_runlatch_off",
554 		"pseries_dedicated_idle_sleep",
555 		NULL
556 	};
557 
558 	int i;
559 
560 	if (!sym)
561 		return false;
562 
563 	for (i = 0; idle_symbols[i]; i++) {
564 		if (!strcmp(idle_symbols[i], sym->name))
565 			return true;
566 	}
567 
568 	return false;
569 }
570 
571 static int map__process_kallsym_symbol(void *arg, const char *name,
572 				       char type, u64 start)
573 {
574 	struct symbol *sym;
575 	struct process_kallsyms_args *a = arg;
576 	struct rb_root *root = &a->dso->symbols[a->map->type];
577 
578 	if (!symbol_type__is_a(type, a->map->type))
579 		return 0;
580 
581 	/*
582 	 * module symbols are not sorted so we add all
583 	 * symbols, setting length to 0, and rely on
584 	 * symbols__fixup_end() to fix it up.
585 	 */
586 	sym = symbol__new(start, 0, kallsyms2elf_binding(type), name);
587 	if (sym == NULL)
588 		return -ENOMEM;
589 	/*
590 	 * We will pass the symbols to the filter later, in
591 	 * map__split_kallsyms, when we have split the maps per module
592 	 */
593 	symbols__insert(root, sym);
594 
595 	return 0;
596 }
597 
598 /*
599  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
600  * so that we can in the next step set the symbol ->end address and then
601  * call kernel_maps__split_kallsyms.
602  */
603 static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
604 				  struct map *map)
605 {
606 	struct process_kallsyms_args args = { .map = map, .dso = dso, };
607 	return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
608 }
609 
610 static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
611 					 symbol_filter_t filter)
612 {
613 	struct map_groups *kmaps = map__kmaps(map);
614 	struct map *curr_map;
615 	struct symbol *pos;
616 	int count = 0;
617 	struct rb_root old_root = dso->symbols[map->type];
618 	struct rb_root *root = &dso->symbols[map->type];
619 	struct rb_node *next = rb_first(root);
620 
621 	if (!kmaps)
622 		return -1;
623 
624 	*root = RB_ROOT;
625 
626 	while (next) {
627 		char *module;
628 
629 		pos = rb_entry(next, struct symbol, rb_node);
630 		next = rb_next(&pos->rb_node);
631 
632 		rb_erase_init(&pos->rb_node, &old_root);
633 
634 		module = strchr(pos->name, '\t');
635 		if (module)
636 			*module = '\0';
637 
638 		curr_map = map_groups__find(kmaps, map->type, pos->start);
639 
640 		if (!curr_map || (filter && filter(curr_map, pos))) {
641 			symbol__delete(pos);
642 			continue;
643 		}
644 
645 		pos->start -= curr_map->start - curr_map->pgoff;
646 		if (pos->end)
647 			pos->end -= curr_map->start - curr_map->pgoff;
648 		symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
649 		++count;
650 	}
651 
652 	/* Symbols have been adjusted */
653 	dso->adjust_symbols = 1;
654 
655 	return count;
656 }
657 
658 /*
659  * Split the symbols into maps, making sure there are no overlaps, i.e. the
660  * kernel range is broken in several maps, named [kernel].N, as we don't have
661  * the original ELF section names vmlinux have.
662  */
663 static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
664 			       symbol_filter_t filter)
665 {
666 	struct map_groups *kmaps = map__kmaps(map);
667 	struct machine *machine;
668 	struct map *curr_map = map;
669 	struct symbol *pos;
670 	int count = 0, moved = 0;
671 	struct rb_root *root = &dso->symbols[map->type];
672 	struct rb_node *next = rb_first(root);
673 	int kernel_range = 0;
674 
675 	if (!kmaps)
676 		return -1;
677 
678 	machine = kmaps->machine;
679 
680 	while (next) {
681 		char *module;
682 
683 		pos = rb_entry(next, struct symbol, rb_node);
684 		next = rb_next(&pos->rb_node);
685 
686 		module = strchr(pos->name, '\t');
687 		if (module) {
688 			if (!symbol_conf.use_modules)
689 				goto discard_symbol;
690 
691 			*module++ = '\0';
692 
693 			if (strcmp(curr_map->dso->short_name, module)) {
694 				if (curr_map != map &&
695 				    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
696 				    machine__is_default_guest(machine)) {
697 					/*
698 					 * We assume all symbols of a module are
699 					 * continuous in * kallsyms, so curr_map
700 					 * points to a module and all its
701 					 * symbols are in its kmap. Mark it as
702 					 * loaded.
703 					 */
704 					dso__set_loaded(curr_map->dso,
705 							curr_map->type);
706 				}
707 
708 				curr_map = map_groups__find_by_name(kmaps,
709 							map->type, module);
710 				if (curr_map == NULL) {
711 					pr_debug("%s/proc/{kallsyms,modules} "
712 					         "inconsistency while looking "
713 						 "for \"%s\" module!\n",
714 						 machine->root_dir, module);
715 					curr_map = map;
716 					goto discard_symbol;
717 				}
718 
719 				if (curr_map->dso->loaded &&
720 				    !machine__is_default_guest(machine))
721 					goto discard_symbol;
722 			}
723 			/*
724 			 * So that we look just like we get from .ko files,
725 			 * i.e. not prelinked, relative to map->start.
726 			 */
727 			pos->start = curr_map->map_ip(curr_map, pos->start);
728 			pos->end   = curr_map->map_ip(curr_map, pos->end);
729 		} else if (curr_map != map) {
730 			char dso_name[PATH_MAX];
731 			struct dso *ndso;
732 
733 			if (delta) {
734 				/* Kernel was relocated at boot time */
735 				pos->start -= delta;
736 				pos->end -= delta;
737 			}
738 
739 			if (count == 0) {
740 				curr_map = map;
741 				goto filter_symbol;
742 			}
743 
744 			if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
745 				snprintf(dso_name, sizeof(dso_name),
746 					"[guest.kernel].%d",
747 					kernel_range++);
748 			else
749 				snprintf(dso_name, sizeof(dso_name),
750 					"[kernel].%d",
751 					kernel_range++);
752 
753 			ndso = dso__new(dso_name);
754 			if (ndso == NULL)
755 				return -1;
756 
757 			ndso->kernel = dso->kernel;
758 
759 			curr_map = map__new2(pos->start, ndso, map->type);
760 			if (curr_map == NULL) {
761 				dso__put(ndso);
762 				return -1;
763 			}
764 
765 			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
766 			map_groups__insert(kmaps, curr_map);
767 			++kernel_range;
768 		} else if (delta) {
769 			/* Kernel was relocated at boot time */
770 			pos->start -= delta;
771 			pos->end -= delta;
772 		}
773 filter_symbol:
774 		if (filter && filter(curr_map, pos)) {
775 discard_symbol:		rb_erase(&pos->rb_node, root);
776 			symbol__delete(pos);
777 		} else {
778 			if (curr_map != map) {
779 				rb_erase(&pos->rb_node, root);
780 				symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
781 				++moved;
782 			} else
783 				++count;
784 		}
785 	}
786 
787 	if (curr_map != map &&
788 	    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
789 	    machine__is_default_guest(kmaps->machine)) {
790 		dso__set_loaded(curr_map->dso, curr_map->type);
791 	}
792 
793 	return count + moved;
794 }
795 
796 bool symbol__restricted_filename(const char *filename,
797 				 const char *restricted_filename)
798 {
799 	bool restricted = false;
800 
801 	if (symbol_conf.kptr_restrict) {
802 		char *r = realpath(filename, NULL);
803 
804 		if (r != NULL) {
805 			restricted = strcmp(r, restricted_filename) == 0;
806 			free(r);
807 			return restricted;
808 		}
809 	}
810 
811 	return restricted;
812 }
813 
814 struct module_info {
815 	struct rb_node rb_node;
816 	char *name;
817 	u64 start;
818 };
819 
820 static void add_module(struct module_info *mi, struct rb_root *modules)
821 {
822 	struct rb_node **p = &modules->rb_node;
823 	struct rb_node *parent = NULL;
824 	struct module_info *m;
825 
826 	while (*p != NULL) {
827 		parent = *p;
828 		m = rb_entry(parent, struct module_info, rb_node);
829 		if (strcmp(mi->name, m->name) < 0)
830 			p = &(*p)->rb_left;
831 		else
832 			p = &(*p)->rb_right;
833 	}
834 	rb_link_node(&mi->rb_node, parent, p);
835 	rb_insert_color(&mi->rb_node, modules);
836 }
837 
838 static void delete_modules(struct rb_root *modules)
839 {
840 	struct module_info *mi;
841 	struct rb_node *next = rb_first(modules);
842 
843 	while (next) {
844 		mi = rb_entry(next, struct module_info, rb_node);
845 		next = rb_next(&mi->rb_node);
846 		rb_erase(&mi->rb_node, modules);
847 		zfree(&mi->name);
848 		free(mi);
849 	}
850 }
851 
852 static struct module_info *find_module(const char *name,
853 				       struct rb_root *modules)
854 {
855 	struct rb_node *n = modules->rb_node;
856 
857 	while (n) {
858 		struct module_info *m;
859 		int cmp;
860 
861 		m = rb_entry(n, struct module_info, rb_node);
862 		cmp = strcmp(name, m->name);
863 		if (cmp < 0)
864 			n = n->rb_left;
865 		else if (cmp > 0)
866 			n = n->rb_right;
867 		else
868 			return m;
869 	}
870 
871 	return NULL;
872 }
873 
874 static int __read_proc_modules(void *arg, const char *name, u64 start)
875 {
876 	struct rb_root *modules = arg;
877 	struct module_info *mi;
878 
879 	mi = zalloc(sizeof(struct module_info));
880 	if (!mi)
881 		return -ENOMEM;
882 
883 	mi->name = strdup(name);
884 	mi->start = start;
885 
886 	if (!mi->name) {
887 		free(mi);
888 		return -ENOMEM;
889 	}
890 
891 	add_module(mi, modules);
892 
893 	return 0;
894 }
895 
896 static int read_proc_modules(const char *filename, struct rb_root *modules)
897 {
898 	if (symbol__restricted_filename(filename, "/proc/modules"))
899 		return -1;
900 
901 	if (modules__parse(filename, modules, __read_proc_modules)) {
902 		delete_modules(modules);
903 		return -1;
904 	}
905 
906 	return 0;
907 }
908 
909 int compare_proc_modules(const char *from, const char *to)
910 {
911 	struct rb_root from_modules = RB_ROOT;
912 	struct rb_root to_modules = RB_ROOT;
913 	struct rb_node *from_node, *to_node;
914 	struct module_info *from_m, *to_m;
915 	int ret = -1;
916 
917 	if (read_proc_modules(from, &from_modules))
918 		return -1;
919 
920 	if (read_proc_modules(to, &to_modules))
921 		goto out_delete_from;
922 
923 	from_node = rb_first(&from_modules);
924 	to_node = rb_first(&to_modules);
925 	while (from_node) {
926 		if (!to_node)
927 			break;
928 
929 		from_m = rb_entry(from_node, struct module_info, rb_node);
930 		to_m = rb_entry(to_node, struct module_info, rb_node);
931 
932 		if (from_m->start != to_m->start ||
933 		    strcmp(from_m->name, to_m->name))
934 			break;
935 
936 		from_node = rb_next(from_node);
937 		to_node = rb_next(to_node);
938 	}
939 
940 	if (!from_node && !to_node)
941 		ret = 0;
942 
943 	delete_modules(&to_modules);
944 out_delete_from:
945 	delete_modules(&from_modules);
946 
947 	return ret;
948 }
949 
950 static int do_validate_kcore_modules(const char *filename, struct map *map,
951 				  struct map_groups *kmaps)
952 {
953 	struct rb_root modules = RB_ROOT;
954 	struct map *old_map;
955 	int err;
956 
957 	err = read_proc_modules(filename, &modules);
958 	if (err)
959 		return err;
960 
961 	old_map = map_groups__first(kmaps, map->type);
962 	while (old_map) {
963 		struct map *next = map_groups__next(old_map);
964 		struct module_info *mi;
965 
966 		if (old_map == map || old_map->start == map->start) {
967 			/* The kernel map */
968 			old_map = next;
969 			continue;
970 		}
971 
972 		/* Module must be in memory at the same address */
973 		mi = find_module(old_map->dso->short_name, &modules);
974 		if (!mi || mi->start != old_map->start) {
975 			err = -EINVAL;
976 			goto out;
977 		}
978 
979 		old_map = next;
980 	}
981 out:
982 	delete_modules(&modules);
983 	return err;
984 }
985 
986 /*
987  * If kallsyms is referenced by name then we look for filename in the same
988  * directory.
989  */
990 static bool filename_from_kallsyms_filename(char *filename,
991 					    const char *base_name,
992 					    const char *kallsyms_filename)
993 {
994 	char *name;
995 
996 	strcpy(filename, kallsyms_filename);
997 	name = strrchr(filename, '/');
998 	if (!name)
999 		return false;
1000 
1001 	name += 1;
1002 
1003 	if (!strcmp(name, "kallsyms")) {
1004 		strcpy(name, base_name);
1005 		return true;
1006 	}
1007 
1008 	return false;
1009 }
1010 
1011 static int validate_kcore_modules(const char *kallsyms_filename,
1012 				  struct map *map)
1013 {
1014 	struct map_groups *kmaps = map__kmaps(map);
1015 	char modules_filename[PATH_MAX];
1016 
1017 	if (!kmaps)
1018 		return -EINVAL;
1019 
1020 	if (!filename_from_kallsyms_filename(modules_filename, "modules",
1021 					     kallsyms_filename))
1022 		return -EINVAL;
1023 
1024 	if (do_validate_kcore_modules(modules_filename, map, kmaps))
1025 		return -EINVAL;
1026 
1027 	return 0;
1028 }
1029 
1030 static int validate_kcore_addresses(const char *kallsyms_filename,
1031 				    struct map *map)
1032 {
1033 	struct kmap *kmap = map__kmap(map);
1034 
1035 	if (!kmap)
1036 		return -EINVAL;
1037 
1038 	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1039 		u64 start;
1040 
1041 		start = kallsyms__get_function_start(kallsyms_filename,
1042 						     kmap->ref_reloc_sym->name);
1043 		if (start != kmap->ref_reloc_sym->addr)
1044 			return -EINVAL;
1045 	}
1046 
1047 	return validate_kcore_modules(kallsyms_filename, map);
1048 }
1049 
1050 struct kcore_mapfn_data {
1051 	struct dso *dso;
1052 	enum map_type type;
1053 	struct list_head maps;
1054 };
1055 
1056 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1057 {
1058 	struct kcore_mapfn_data *md = data;
1059 	struct map *map;
1060 
1061 	map = map__new2(start, md->dso, md->type);
1062 	if (map == NULL)
1063 		return -ENOMEM;
1064 
1065 	map->end = map->start + len;
1066 	map->pgoff = pgoff;
1067 
1068 	list_add(&map->node, &md->maps);
1069 
1070 	return 0;
1071 }
1072 
1073 static int dso__load_kcore(struct dso *dso, struct map *map,
1074 			   const char *kallsyms_filename)
1075 {
1076 	struct map_groups *kmaps = map__kmaps(map);
1077 	struct machine *machine;
1078 	struct kcore_mapfn_data md;
1079 	struct map *old_map, *new_map, *replacement_map = NULL;
1080 	bool is_64_bit;
1081 	int err, fd;
1082 	char kcore_filename[PATH_MAX];
1083 	struct symbol *sym;
1084 
1085 	if (!kmaps)
1086 		return -EINVAL;
1087 
1088 	machine = kmaps->machine;
1089 
1090 	/* This function requires that the map is the kernel map */
1091 	if (map != machine->vmlinux_maps[map->type])
1092 		return -EINVAL;
1093 
1094 	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1095 					     kallsyms_filename))
1096 		return -EINVAL;
1097 
1098 	/* Modules and kernel must be present at their original addresses */
1099 	if (validate_kcore_addresses(kallsyms_filename, map))
1100 		return -EINVAL;
1101 
1102 	md.dso = dso;
1103 	md.type = map->type;
1104 	INIT_LIST_HEAD(&md.maps);
1105 
1106 	fd = open(kcore_filename, O_RDONLY);
1107 	if (fd < 0) {
1108 		pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1109 			 kcore_filename);
1110 		return -EINVAL;
1111 	}
1112 
1113 	/* Read new maps into temporary lists */
1114 	err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
1115 			      &is_64_bit);
1116 	if (err)
1117 		goto out_err;
1118 	dso->is_64_bit = is_64_bit;
1119 
1120 	if (list_empty(&md.maps)) {
1121 		err = -EINVAL;
1122 		goto out_err;
1123 	}
1124 
1125 	/* Remove old maps */
1126 	old_map = map_groups__first(kmaps, map->type);
1127 	while (old_map) {
1128 		struct map *next = map_groups__next(old_map);
1129 
1130 		if (old_map != map)
1131 			map_groups__remove(kmaps, old_map);
1132 		old_map = next;
1133 	}
1134 
1135 	/* Find the kernel map using the first symbol */
1136 	sym = dso__first_symbol(dso, map->type);
1137 	list_for_each_entry(new_map, &md.maps, node) {
1138 		if (sym && sym->start >= new_map->start &&
1139 		    sym->start < new_map->end) {
1140 			replacement_map = new_map;
1141 			break;
1142 		}
1143 	}
1144 
1145 	if (!replacement_map)
1146 		replacement_map = list_entry(md.maps.next, struct map, node);
1147 
1148 	/* Add new maps */
1149 	while (!list_empty(&md.maps)) {
1150 		new_map = list_entry(md.maps.next, struct map, node);
1151 		list_del_init(&new_map->node);
1152 		if (new_map == replacement_map) {
1153 			map->start	= new_map->start;
1154 			map->end	= new_map->end;
1155 			map->pgoff	= new_map->pgoff;
1156 			map->map_ip	= new_map->map_ip;
1157 			map->unmap_ip	= new_map->unmap_ip;
1158 			/* Ensure maps are correctly ordered */
1159 			map__get(map);
1160 			map_groups__remove(kmaps, map);
1161 			map_groups__insert(kmaps, map);
1162 			map__put(map);
1163 		} else {
1164 			map_groups__insert(kmaps, new_map);
1165 		}
1166 
1167 		map__put(new_map);
1168 	}
1169 
1170 	/*
1171 	 * Set the data type and long name so that kcore can be read via
1172 	 * dso__data_read_addr().
1173 	 */
1174 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1175 		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1176 	else
1177 		dso->binary_type = DSO_BINARY_TYPE__KCORE;
1178 	dso__set_long_name(dso, strdup(kcore_filename), true);
1179 
1180 	close(fd);
1181 
1182 	if (map->type == MAP__FUNCTION)
1183 		pr_debug("Using %s for kernel object code\n", kcore_filename);
1184 	else
1185 		pr_debug("Using %s for kernel data\n", kcore_filename);
1186 
1187 	return 0;
1188 
1189 out_err:
1190 	while (!list_empty(&md.maps)) {
1191 		map = list_entry(md.maps.next, struct map, node);
1192 		list_del_init(&map->node);
1193 		map__put(map);
1194 	}
1195 	close(fd);
1196 	return -EINVAL;
1197 }
1198 
1199 /*
1200  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1201  * delta based on the relocation reference symbol.
1202  */
1203 static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
1204 {
1205 	struct kmap *kmap = map__kmap(map);
1206 	u64 addr;
1207 
1208 	if (!kmap)
1209 		return -1;
1210 
1211 	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1212 		return 0;
1213 
1214 	addr = kallsyms__get_function_start(filename,
1215 					    kmap->ref_reloc_sym->name);
1216 	if (!addr)
1217 		return -1;
1218 
1219 	*delta = addr - kmap->ref_reloc_sym->addr;
1220 	return 0;
1221 }
1222 
1223 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1224 			 struct map *map, bool no_kcore, symbol_filter_t filter)
1225 {
1226 	u64 delta = 0;
1227 
1228 	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1229 		return -1;
1230 
1231 	if (dso__load_all_kallsyms(dso, filename, map) < 0)
1232 		return -1;
1233 
1234 	if (kallsyms__delta(map, filename, &delta))
1235 		return -1;
1236 
1237 	symbols__fixup_duplicate(&dso->symbols[map->type]);
1238 	symbols__fixup_end(&dso->symbols[map->type]);
1239 
1240 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1241 		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1242 	else
1243 		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1244 
1245 	if (!no_kcore && !dso__load_kcore(dso, map, filename))
1246 		return dso__split_kallsyms_for_kcore(dso, map, filter);
1247 	else
1248 		return dso__split_kallsyms(dso, map, delta, filter);
1249 }
1250 
1251 int dso__load_kallsyms(struct dso *dso, const char *filename,
1252 		       struct map *map, symbol_filter_t filter)
1253 {
1254 	return __dso__load_kallsyms(dso, filename, map, false, filter);
1255 }
1256 
1257 static int dso__load_perf_map(struct dso *dso, struct map *map,
1258 			      symbol_filter_t filter)
1259 {
1260 	char *line = NULL;
1261 	size_t n;
1262 	FILE *file;
1263 	int nr_syms = 0;
1264 
1265 	file = fopen(dso->long_name, "r");
1266 	if (file == NULL)
1267 		goto out_failure;
1268 
1269 	while (!feof(file)) {
1270 		u64 start, size;
1271 		struct symbol *sym;
1272 		int line_len, len;
1273 
1274 		line_len = getline(&line, &n, file);
1275 		if (line_len < 0)
1276 			break;
1277 
1278 		if (!line)
1279 			goto out_failure;
1280 
1281 		line[--line_len] = '\0'; /* \n */
1282 
1283 		len = hex2u64(line, &start);
1284 
1285 		len++;
1286 		if (len + 2 >= line_len)
1287 			continue;
1288 
1289 		len += hex2u64(line + len, &size);
1290 
1291 		len++;
1292 		if (len + 2 >= line_len)
1293 			continue;
1294 
1295 		sym = symbol__new(start, size, STB_GLOBAL, line + len);
1296 
1297 		if (sym == NULL)
1298 			goto out_delete_line;
1299 
1300 		if (filter && filter(map, sym))
1301 			symbol__delete(sym);
1302 		else {
1303 			symbols__insert(&dso->symbols[map->type], sym);
1304 			nr_syms++;
1305 		}
1306 	}
1307 
1308 	free(line);
1309 	fclose(file);
1310 
1311 	return nr_syms;
1312 
1313 out_delete_line:
1314 	free(line);
1315 out_failure:
1316 	return -1;
1317 }
1318 
1319 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1320 					   enum dso_binary_type type)
1321 {
1322 	switch (type) {
1323 	case DSO_BINARY_TYPE__JAVA_JIT:
1324 	case DSO_BINARY_TYPE__DEBUGLINK:
1325 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1326 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1327 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1328 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1329 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1330 		return !kmod && dso->kernel == DSO_TYPE_USER;
1331 
1332 	case DSO_BINARY_TYPE__KALLSYMS:
1333 	case DSO_BINARY_TYPE__VMLINUX:
1334 	case DSO_BINARY_TYPE__KCORE:
1335 		return dso->kernel == DSO_TYPE_KERNEL;
1336 
1337 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1338 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
1339 	case DSO_BINARY_TYPE__GUEST_KCORE:
1340 		return dso->kernel == DSO_TYPE_GUEST_KERNEL;
1341 
1342 	case DSO_BINARY_TYPE__GUEST_KMODULE:
1343 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1344 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1345 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1346 		/*
1347 		 * kernel modules know their symtab type - it's set when
1348 		 * creating a module dso in machine__findnew_module_map().
1349 		 */
1350 		return kmod && dso->symtab_type == type;
1351 
1352 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1353 		return true;
1354 
1355 	case DSO_BINARY_TYPE__NOT_FOUND:
1356 	default:
1357 		return false;
1358 	}
1359 }
1360 
1361 int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1362 {
1363 	char *name;
1364 	int ret = -1;
1365 	u_int i;
1366 	struct machine *machine;
1367 	char *root_dir = (char *) "";
1368 	int ss_pos = 0;
1369 	struct symsrc ss_[2];
1370 	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1371 	bool kmod;
1372 	unsigned char build_id[BUILD_ID_SIZE];
1373 
1374 	pthread_mutex_lock(&dso->lock);
1375 
1376 	/* check again under the dso->lock */
1377 	if (dso__loaded(dso, map->type)) {
1378 		ret = 1;
1379 		goto out;
1380 	}
1381 
1382 	if (dso->kernel) {
1383 		if (dso->kernel == DSO_TYPE_KERNEL)
1384 			ret = dso__load_kernel_sym(dso, map, filter);
1385 		else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1386 			ret = dso__load_guest_kernel_sym(dso, map, filter);
1387 
1388 		goto out;
1389 	}
1390 
1391 	if (map->groups && map->groups->machine)
1392 		machine = map->groups->machine;
1393 	else
1394 		machine = NULL;
1395 
1396 	dso->adjust_symbols = 0;
1397 
1398 	if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1399 		struct stat st;
1400 
1401 		if (lstat(dso->name, &st) < 0)
1402 			goto out;
1403 
1404 		if (!symbol_conf.force && st.st_uid && (st.st_uid != geteuid())) {
1405 			pr_warning("File %s not owned by current user or root, "
1406 				   "ignoring it (use -f to override).\n", dso->name);
1407 			goto out;
1408 		}
1409 
1410 		ret = dso__load_perf_map(dso, map, filter);
1411 		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
1412 					     DSO_BINARY_TYPE__NOT_FOUND;
1413 		goto out;
1414 	}
1415 
1416 	if (machine)
1417 		root_dir = machine->root_dir;
1418 
1419 	name = malloc(PATH_MAX);
1420 	if (!name)
1421 		goto out;
1422 
1423 	kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
1424 		dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
1425 		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
1426 		dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
1427 
1428 
1429 	/*
1430 	 * Read the build id if possible. This is required for
1431 	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
1432 	 */
1433 	if (is_regular_file(name) &&
1434 	    filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0)
1435 		dso__set_build_id(dso, build_id);
1436 
1437 	/*
1438 	 * Iterate over candidate debug images.
1439 	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1440 	 * and/or opd section) for processing.
1441 	 */
1442 	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1443 		struct symsrc *ss = &ss_[ss_pos];
1444 		bool next_slot = false;
1445 
1446 		enum dso_binary_type symtab_type = binary_type_symtab[i];
1447 
1448 		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1449 			continue;
1450 
1451 		if (dso__read_binary_type_filename(dso, symtab_type,
1452 						   root_dir, name, PATH_MAX))
1453 			continue;
1454 
1455 		if (!is_regular_file(name))
1456 			continue;
1457 
1458 		/* Name is now the name of the next image to try */
1459 		if (symsrc__init(ss, dso, name, symtab_type) < 0)
1460 			continue;
1461 
1462 		if (!syms_ss && symsrc__has_symtab(ss)) {
1463 			syms_ss = ss;
1464 			next_slot = true;
1465 			if (!dso->symsrc_filename)
1466 				dso->symsrc_filename = strdup(name);
1467 		}
1468 
1469 		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1470 			runtime_ss = ss;
1471 			next_slot = true;
1472 		}
1473 
1474 		if (next_slot) {
1475 			ss_pos++;
1476 
1477 			if (syms_ss && runtime_ss)
1478 				break;
1479 		} else {
1480 			symsrc__destroy(ss);
1481 		}
1482 
1483 	}
1484 
1485 	if (!runtime_ss && !syms_ss)
1486 		goto out_free;
1487 
1488 	if (runtime_ss && !syms_ss) {
1489 		syms_ss = runtime_ss;
1490 	}
1491 
1492 	/* We'll have to hope for the best */
1493 	if (!runtime_ss && syms_ss)
1494 		runtime_ss = syms_ss;
1495 
1496 	if (syms_ss && syms_ss->type == DSO_BINARY_TYPE__BUILD_ID_CACHE)
1497 		if (dso__build_id_is_kmod(dso, name, PATH_MAX))
1498 			kmod = true;
1499 
1500 	if (syms_ss)
1501 		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, kmod);
1502 	else
1503 		ret = -1;
1504 
1505 	if (ret > 0) {
1506 		int nr_plt;
1507 
1508 		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
1509 		if (nr_plt > 0)
1510 			ret += nr_plt;
1511 	}
1512 
1513 	for (; ss_pos > 0; ss_pos--)
1514 		symsrc__destroy(&ss_[ss_pos - 1]);
1515 out_free:
1516 	free(name);
1517 	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1518 		ret = 0;
1519 out:
1520 	dso__set_loaded(dso, map->type);
1521 	pthread_mutex_unlock(&dso->lock);
1522 
1523 	return ret;
1524 }
1525 
1526 struct map *map_groups__find_by_name(struct map_groups *mg,
1527 				     enum map_type type, const char *name)
1528 {
1529 	struct maps *maps = &mg->maps[type];
1530 	struct map *map;
1531 
1532 	pthread_rwlock_rdlock(&maps->lock);
1533 
1534 	for (map = maps__first(maps); map; map = map__next(map)) {
1535 		if (map->dso && strcmp(map->dso->short_name, name) == 0)
1536 			goto out_unlock;
1537 	}
1538 
1539 	map = NULL;
1540 
1541 out_unlock:
1542 	pthread_rwlock_unlock(&maps->lock);
1543 	return map;
1544 }
1545 
1546 int dso__load_vmlinux(struct dso *dso, struct map *map,
1547 		      const char *vmlinux, bool vmlinux_allocated,
1548 		      symbol_filter_t filter)
1549 {
1550 	int err = -1;
1551 	struct symsrc ss;
1552 	char symfs_vmlinux[PATH_MAX];
1553 	enum dso_binary_type symtab_type;
1554 
1555 	if (vmlinux[0] == '/')
1556 		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
1557 	else
1558 		symbol__join_symfs(symfs_vmlinux, vmlinux);
1559 
1560 	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1561 		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1562 	else
1563 		symtab_type = DSO_BINARY_TYPE__VMLINUX;
1564 
1565 	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1566 		return -1;
1567 
1568 	err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1569 	symsrc__destroy(&ss);
1570 
1571 	if (err > 0) {
1572 		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1573 			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1574 		else
1575 			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1576 		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1577 		dso__set_loaded(dso, map->type);
1578 		pr_debug("Using %s for symbols\n", symfs_vmlinux);
1579 	}
1580 
1581 	return err;
1582 }
1583 
1584 int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1585 			   symbol_filter_t filter)
1586 {
1587 	int i, err = 0;
1588 	char *filename = NULL;
1589 
1590 	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1591 		 vmlinux_path__nr_entries + 1);
1592 
1593 	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1594 		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
1595 		if (err > 0)
1596 			goto out;
1597 	}
1598 
1599 	if (!symbol_conf.ignore_vmlinux_buildid)
1600 		filename = dso__build_id_filename(dso, NULL, 0);
1601 	if (filename != NULL) {
1602 		err = dso__load_vmlinux(dso, map, filename, true, filter);
1603 		if (err > 0)
1604 			goto out;
1605 		free(filename);
1606 	}
1607 out:
1608 	return err;
1609 }
1610 
1611 static bool visible_dir_filter(const char *name, struct dirent *d)
1612 {
1613 	if (d->d_type != DT_DIR)
1614 		return false;
1615 	return lsdir_no_dot_filter(name, d);
1616 }
1617 
1618 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
1619 {
1620 	char kallsyms_filename[PATH_MAX];
1621 	int ret = -1;
1622 	struct strlist *dirs;
1623 	struct str_node *nd;
1624 
1625 	dirs = lsdir(dir, visible_dir_filter);
1626 	if (!dirs)
1627 		return -1;
1628 
1629 	strlist__for_each(nd, dirs) {
1630 		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
1631 			  "%s/%s/kallsyms", dir, nd->s);
1632 		if (!validate_kcore_addresses(kallsyms_filename, map)) {
1633 			strlcpy(dir, kallsyms_filename, dir_sz);
1634 			ret = 0;
1635 			break;
1636 		}
1637 	}
1638 
1639 	strlist__delete(dirs);
1640 
1641 	return ret;
1642 }
1643 
1644 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
1645 {
1646 	u8 host_build_id[BUILD_ID_SIZE];
1647 	char sbuild_id[SBUILD_ID_SIZE];
1648 	bool is_host = false;
1649 	char path[PATH_MAX];
1650 
1651 	if (!dso->has_build_id) {
1652 		/*
1653 		 * Last resort, if we don't have a build-id and couldn't find
1654 		 * any vmlinux file, try the running kernel kallsyms table.
1655 		 */
1656 		goto proc_kallsyms;
1657 	}
1658 
1659 	if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
1660 				 sizeof(host_build_id)) == 0)
1661 		is_host = dso__build_id_equal(dso, host_build_id);
1662 
1663 	build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
1664 
1665 	scnprintf(path, sizeof(path), "%s/%s/%s", buildid_dir,
1666 		  DSO__NAME_KCORE, sbuild_id);
1667 
1668 	/* Use /proc/kallsyms if possible */
1669 	if (is_host) {
1670 		DIR *d;
1671 		int fd;
1672 
1673 		/* If no cached kcore go with /proc/kallsyms */
1674 		d = opendir(path);
1675 		if (!d)
1676 			goto proc_kallsyms;
1677 		closedir(d);
1678 
1679 		/*
1680 		 * Do not check the build-id cache, until we know we cannot use
1681 		 * /proc/kcore.
1682 		 */
1683 		fd = open("/proc/kcore", O_RDONLY);
1684 		if (fd != -1) {
1685 			close(fd);
1686 			/* If module maps match go with /proc/kallsyms */
1687 			if (!validate_kcore_addresses("/proc/kallsyms", map))
1688 				goto proc_kallsyms;
1689 		}
1690 
1691 		/* Find kallsyms in build-id cache with kcore */
1692 		if (!find_matching_kcore(map, path, sizeof(path)))
1693 			return strdup(path);
1694 
1695 		goto proc_kallsyms;
1696 	}
1697 
1698 	/* Find kallsyms in build-id cache with kcore */
1699 	if (!find_matching_kcore(map, path, sizeof(path)))
1700 		return strdup(path);
1701 
1702 	scnprintf(path, sizeof(path), "%s/%s/%s",
1703 		  buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
1704 
1705 	if (access(path, F_OK)) {
1706 		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
1707 		       sbuild_id);
1708 		return NULL;
1709 	}
1710 
1711 	return strdup(path);
1712 
1713 proc_kallsyms:
1714 	return strdup("/proc/kallsyms");
1715 }
1716 
1717 static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1718 				symbol_filter_t filter)
1719 {
1720 	int err;
1721 	const char *kallsyms_filename = NULL;
1722 	char *kallsyms_allocated_filename = NULL;
1723 	/*
1724 	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
1725 	 * it and only it, reporting errors to the user if it cannot be used.
1726 	 *
1727 	 * For instance, try to analyse an ARM perf.data file _without_ a
1728 	 * build-id, or if the user specifies the wrong path to the right
1729 	 * vmlinux file, obviously we can't fallback to another vmlinux (a
1730 	 * x86_86 one, on the machine where analysis is being performed, say),
1731 	 * or worse, /proc/kallsyms.
1732 	 *
1733 	 * If the specified file _has_ a build-id and there is a build-id
1734 	 * section in the perf.data file, we will still do the expected
1735 	 * validation in dso__load_vmlinux and will bail out if they don't
1736 	 * match.
1737 	 */
1738 	if (symbol_conf.kallsyms_name != NULL) {
1739 		kallsyms_filename = symbol_conf.kallsyms_name;
1740 		goto do_kallsyms;
1741 	}
1742 
1743 	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1744 		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
1745 					 false, filter);
1746 	}
1747 
1748 	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1749 		err = dso__load_vmlinux_path(dso, map, filter);
1750 		if (err > 0)
1751 			return err;
1752 	}
1753 
1754 	/* do not try local files if a symfs was given */
1755 	if (symbol_conf.symfs[0] != 0)
1756 		return -1;
1757 
1758 	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
1759 	if (!kallsyms_allocated_filename)
1760 		return -1;
1761 
1762 	kallsyms_filename = kallsyms_allocated_filename;
1763 
1764 do_kallsyms:
1765 	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1766 	if (err > 0)
1767 		pr_debug("Using %s for symbols\n", kallsyms_filename);
1768 	free(kallsyms_allocated_filename);
1769 
1770 	if (err > 0 && !dso__is_kcore(dso)) {
1771 		dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
1772 		dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
1773 		map__fixup_start(map);
1774 		map__fixup_end(map);
1775 	}
1776 
1777 	return err;
1778 }
1779 
1780 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
1781 				      symbol_filter_t filter)
1782 {
1783 	int err;
1784 	const char *kallsyms_filename = NULL;
1785 	struct machine *machine;
1786 	char path[PATH_MAX];
1787 
1788 	if (!map->groups) {
1789 		pr_debug("Guest kernel map hasn't the point to groups\n");
1790 		return -1;
1791 	}
1792 	machine = map->groups->machine;
1793 
1794 	if (machine__is_default_guest(machine)) {
1795 		/*
1796 		 * if the user specified a vmlinux filename, use it and only
1797 		 * it, reporting errors to the user if it cannot be used.
1798 		 * Or use file guest_kallsyms inputted by user on commandline
1799 		 */
1800 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
1801 			err = dso__load_vmlinux(dso, map,
1802 						symbol_conf.default_guest_vmlinux_name,
1803 						false, filter);
1804 			return err;
1805 		}
1806 
1807 		kallsyms_filename = symbol_conf.default_guest_kallsyms;
1808 		if (!kallsyms_filename)
1809 			return -1;
1810 	} else {
1811 		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1812 		kallsyms_filename = path;
1813 	}
1814 
1815 	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1816 	if (err > 0)
1817 		pr_debug("Using %s for symbols\n", kallsyms_filename);
1818 	if (err > 0 && !dso__is_kcore(dso)) {
1819 		dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1820 		machine__mmap_name(machine, path, sizeof(path));
1821 		dso__set_long_name(dso, strdup(path), true);
1822 		map__fixup_start(map);
1823 		map__fixup_end(map);
1824 	}
1825 
1826 	return err;
1827 }
1828 
1829 static void vmlinux_path__exit(void)
1830 {
1831 	while (--vmlinux_path__nr_entries >= 0)
1832 		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1833 	vmlinux_path__nr_entries = 0;
1834 
1835 	zfree(&vmlinux_path);
1836 }
1837 
1838 static const char * const vmlinux_paths[] = {
1839 	"vmlinux",
1840 	"/boot/vmlinux"
1841 };
1842 
1843 static const char * const vmlinux_paths_upd[] = {
1844 	"/boot/vmlinux-%s",
1845 	"/usr/lib/debug/boot/vmlinux-%s",
1846 	"/lib/modules/%s/build/vmlinux",
1847 	"/usr/lib/debug/lib/modules/%s/vmlinux",
1848 	"/usr/lib/debug/boot/vmlinux-%s.debug"
1849 };
1850 
1851 static int vmlinux_path__add(const char *new_entry)
1852 {
1853 	vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
1854 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
1855 		return -1;
1856 	++vmlinux_path__nr_entries;
1857 
1858 	return 0;
1859 }
1860 
1861 static int vmlinux_path__init(struct perf_env *env)
1862 {
1863 	struct utsname uts;
1864 	char bf[PATH_MAX];
1865 	char *kernel_version;
1866 	unsigned int i;
1867 
1868 	vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
1869 			      ARRAY_SIZE(vmlinux_paths_upd)));
1870 	if (vmlinux_path == NULL)
1871 		return -1;
1872 
1873 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
1874 		if (vmlinux_path__add(vmlinux_paths[i]) < 0)
1875 			goto out_fail;
1876 
1877 	/* only try kernel version if no symfs was given */
1878 	if (symbol_conf.symfs[0] != 0)
1879 		return 0;
1880 
1881 	if (env) {
1882 		kernel_version = env->os_release;
1883 	} else {
1884 		if (uname(&uts) < 0)
1885 			goto out_fail;
1886 
1887 		kernel_version = uts.release;
1888 	}
1889 
1890 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
1891 		snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
1892 		if (vmlinux_path__add(bf) < 0)
1893 			goto out_fail;
1894 	}
1895 
1896 	return 0;
1897 
1898 out_fail:
1899 	vmlinux_path__exit();
1900 	return -1;
1901 }
1902 
1903 int setup_list(struct strlist **list, const char *list_str,
1904 		      const char *list_name)
1905 {
1906 	if (list_str == NULL)
1907 		return 0;
1908 
1909 	*list = strlist__new(list_str, NULL);
1910 	if (!*list) {
1911 		pr_err("problems parsing %s list\n", list_name);
1912 		return -1;
1913 	}
1914 
1915 	symbol_conf.has_filter = true;
1916 	return 0;
1917 }
1918 
1919 int setup_intlist(struct intlist **list, const char *list_str,
1920 		  const char *list_name)
1921 {
1922 	if (list_str == NULL)
1923 		return 0;
1924 
1925 	*list = intlist__new(list_str);
1926 	if (!*list) {
1927 		pr_err("problems parsing %s list\n", list_name);
1928 		return -1;
1929 	}
1930 	return 0;
1931 }
1932 
1933 static bool symbol__read_kptr_restrict(void)
1934 {
1935 	bool value = false;
1936 	FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
1937 
1938 	if (fp != NULL) {
1939 		char line[8];
1940 
1941 		if (fgets(line, sizeof(line), fp) != NULL)
1942 			value = (geteuid() != 0) ?
1943 					(atoi(line) != 0) :
1944 					(atoi(line) == 2);
1945 
1946 		fclose(fp);
1947 	}
1948 
1949 	return value;
1950 }
1951 
1952 int symbol__init(struct perf_env *env)
1953 {
1954 	const char *symfs;
1955 
1956 	if (symbol_conf.initialized)
1957 		return 0;
1958 
1959 	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1960 
1961 	symbol__elf_init();
1962 
1963 	if (symbol_conf.sort_by_name)
1964 		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
1965 					  sizeof(struct symbol));
1966 
1967 	if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
1968 		return -1;
1969 
1970 	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
1971 		pr_err("'.' is the only non valid --field-separator argument\n");
1972 		return -1;
1973 	}
1974 
1975 	if (setup_list(&symbol_conf.dso_list,
1976 		       symbol_conf.dso_list_str, "dso") < 0)
1977 		return -1;
1978 
1979 	if (setup_list(&symbol_conf.comm_list,
1980 		       symbol_conf.comm_list_str, "comm") < 0)
1981 		goto out_free_dso_list;
1982 
1983 	if (setup_intlist(&symbol_conf.pid_list,
1984 		       symbol_conf.pid_list_str, "pid") < 0)
1985 		goto out_free_comm_list;
1986 
1987 	if (setup_intlist(&symbol_conf.tid_list,
1988 		       symbol_conf.tid_list_str, "tid") < 0)
1989 		goto out_free_pid_list;
1990 
1991 	if (setup_list(&symbol_conf.sym_list,
1992 		       symbol_conf.sym_list_str, "symbol") < 0)
1993 		goto out_free_tid_list;
1994 
1995 	/*
1996 	 * A path to symbols of "/" is identical to ""
1997 	 * reset here for simplicity.
1998 	 */
1999 	symfs = realpath(symbol_conf.symfs, NULL);
2000 	if (symfs == NULL)
2001 		symfs = symbol_conf.symfs;
2002 	if (strcmp(symfs, "/") == 0)
2003 		symbol_conf.symfs = "";
2004 	if (symfs != symbol_conf.symfs)
2005 		free((void *)symfs);
2006 
2007 	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2008 
2009 	symbol_conf.initialized = true;
2010 	return 0;
2011 
2012 out_free_tid_list:
2013 	intlist__delete(symbol_conf.tid_list);
2014 out_free_pid_list:
2015 	intlist__delete(symbol_conf.pid_list);
2016 out_free_comm_list:
2017 	strlist__delete(symbol_conf.comm_list);
2018 out_free_dso_list:
2019 	strlist__delete(symbol_conf.dso_list);
2020 	return -1;
2021 }
2022 
2023 void symbol__exit(void)
2024 {
2025 	if (!symbol_conf.initialized)
2026 		return;
2027 	strlist__delete(symbol_conf.sym_list);
2028 	strlist__delete(symbol_conf.dso_list);
2029 	strlist__delete(symbol_conf.comm_list);
2030 	intlist__delete(symbol_conf.tid_list);
2031 	intlist__delete(symbol_conf.pid_list);
2032 	vmlinux_path__exit();
2033 	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2034 	symbol_conf.initialized = false;
2035 }
2036 
2037 int symbol__config_symfs(const struct option *opt __maybe_unused,
2038 			 const char *dir, int unset __maybe_unused)
2039 {
2040 	char *bf = NULL;
2041 	int ret;
2042 
2043 	symbol_conf.symfs = strdup(dir);
2044 	if (symbol_conf.symfs == NULL)
2045 		return -ENOMEM;
2046 
2047 	/* skip the locally configured cache if a symfs is given, and
2048 	 * config buildid dir to symfs/.debug
2049 	 */
2050 	ret = asprintf(&bf, "%s/%s", dir, ".debug");
2051 	if (ret < 0)
2052 		return -ENOMEM;
2053 
2054 	set_buildid_dir(bf);
2055 
2056 	free(bf);
2057 	return 0;
2058 }
2059