xref: /linux/tools/perf/util/symbol.c (revision 8dc364fa484df22d301a16148d1b356931d0cbb0)
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 "cpumap.h"
22 #include "debug.h"
23 #include "demangle-cxx.h"
24 #include "demangle-java.h"
25 #include "demangle-ocaml.h"
26 #include "demangle-rust-v0.h"
27 #include "dso.h"
28 #include "util.h" // lsdir()
29 #include "debug.h"
30 #include "event.h"
31 #include "machine.h"
32 #include "map.h"
33 #include "symbol.h"
34 #include "map_symbol.h"
35 #include "mem-events.h"
36 #include "mem-info.h"
37 #include "symsrc.h"
38 #include "strlist.h"
39 #include "intlist.h"
40 #include "namespaces.h"
41 #include "header.h"
42 #include "path.h"
43 #include <linux/ctype.h>
44 #include <linux/log2.h>
45 #include <linux/zalloc.h>
46 
47 #include <elf.h>
48 #include <limits.h>
49 #include <symbol/kallsyms.h>
50 #include <sys/utsname.h>
51 
52 static int dso__load_kernel_sym(struct dso *dso, struct map *map);
53 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
54 static bool symbol__is_idle(const char *name);
55 
56 int vmlinux_path__nr_entries;
57 char **vmlinux_path;
58 
59 struct symbol_conf symbol_conf = {
60 	.nanosecs		= false,
61 	.use_modules		= true,
62 	.try_vmlinux_path	= true,
63 	.demangle		= true,
64 	.demangle_kernel	= false,
65 	.cumulate_callchain	= true,
66 	.time_quantum		= 100 * NSEC_PER_MSEC, /* 100ms */
67 	.show_hist_headers	= true,
68 	.symfs			= "",
69 	.event_group		= true,
70 	.inline_name		= true,
71 	.res_sample		= 0,
72 };
73 
74 struct map_list_node {
75 	struct list_head node;
76 	struct map *map;
77 };
78 
79 static struct map_list_node *map_list_node__new(void)
80 {
81 	return malloc(sizeof(struct map_list_node));
82 }
83 
84 static enum dso_binary_type binary_type_symtab[] = {
85 	DSO_BINARY_TYPE__KALLSYMS,
86 	DSO_BINARY_TYPE__GUEST_KALLSYMS,
87 	DSO_BINARY_TYPE__JAVA_JIT,
88 	DSO_BINARY_TYPE__DEBUGLINK,
89 	DSO_BINARY_TYPE__BUILD_ID_CACHE,
90 	DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
91 	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
92 	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
93 	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
94 	DSO_BINARY_TYPE__GNU_DEBUGDATA,
95 	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
96 	DSO_BINARY_TYPE__GUEST_KMODULE,
97 	DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
98 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
99 	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
100 	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
101 	DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO,
102 	DSO_BINARY_TYPE__NOT_FOUND,
103 };
104 
105 #define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
106 
107 static bool symbol_type__filter(char __symbol_type)
108 {
109 	// Since 'U' == undefined and 'u' == unique global symbol, we can't use toupper there
110 	// 'N' is for debugging symbols, 'n' is a non-data, non-code, non-debug read-only section.
111 	// According to 'man nm'.
112 	// 'N' first seen in:
113 	// ffffffff9b35d130 N __pfx__RNCINvNtNtNtCsbDUBuN8AbD4_4core4iter8adapters3map12map_try_foldjNtCs6vVzKs5jPr6_12drm_panic_qr7VersionuINtNtNtBa_3ops12control_flow11ControlFlowB10_ENcB10_0NCINvNvNtNtNtB8_6traits8iterator8Iterator4find5checkB10_NCNvMB12_B10_13from_segments0E0E0B12_
114 	// a seemingly Rust mangled name
115 	char symbol_type = toupper(__symbol_type);
116 	return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B' ||
117 	       __symbol_type == 'u' || __symbol_type == 'l' || __symbol_type == 'N';
118 }
119 
120 static int prefix_underscores_count(const char *str)
121 {
122 	const char *tail = str;
123 
124 	while (*tail == '_')
125 		tail++;
126 
127 	return tail - str;
128 }
129 
130 const char * __weak arch__normalize_symbol_name(const char *name)
131 {
132 	return name;
133 }
134 
135 int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
136 {
137 	return strcmp(namea, nameb);
138 }
139 
140 int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
141 					unsigned int n)
142 {
143 	return strncmp(namea, nameb, n);
144 }
145 
146 int __weak arch__choose_best_symbol(struct symbol *syma,
147 				    struct symbol *symb __maybe_unused)
148 {
149 	/* Avoid "SyS" kernel syscall aliases */
150 	if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
151 		return SYMBOL_B;
152 	if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
153 		return SYMBOL_B;
154 
155 	return SYMBOL_A;
156 }
157 
158 static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
159 {
160 	s64 a;
161 	s64 b;
162 	size_t na, nb;
163 
164 	/* Prefer a symbol with non zero length */
165 	a = syma->end - syma->start;
166 	b = symb->end - symb->start;
167 	if ((b == 0) && (a > 0))
168 		return SYMBOL_A;
169 	else if ((a == 0) && (b > 0))
170 		return SYMBOL_B;
171 
172 	if (syma->type != symb->type) {
173 		if (syma->type == STT_NOTYPE)
174 			return SYMBOL_B;
175 		if (symb->type == STT_NOTYPE)
176 			return SYMBOL_A;
177 	}
178 
179 	/* Prefer a non weak symbol over a weak one */
180 	a = syma->binding == STB_WEAK;
181 	b = symb->binding == STB_WEAK;
182 	if (b && !a)
183 		return SYMBOL_A;
184 	if (a && !b)
185 		return SYMBOL_B;
186 
187 	/* Prefer a global symbol over a non global one */
188 	a = syma->binding == STB_GLOBAL;
189 	b = symb->binding == STB_GLOBAL;
190 	if (a && !b)
191 		return SYMBOL_A;
192 	if (b && !a)
193 		return SYMBOL_B;
194 
195 	/* Prefer a symbol with less underscores */
196 	a = prefix_underscores_count(syma->name);
197 	b = prefix_underscores_count(symb->name);
198 	if (b > a)
199 		return SYMBOL_A;
200 	else if (a > b)
201 		return SYMBOL_B;
202 
203 	/* Choose the symbol with the longest name */
204 	na = strlen(syma->name);
205 	nb = strlen(symb->name);
206 	if (na > nb)
207 		return SYMBOL_A;
208 	else if (na < nb)
209 		return SYMBOL_B;
210 
211 	return arch__choose_best_symbol(syma, symb);
212 }
213 
214 void symbols__fixup_duplicate(struct rb_root_cached *symbols)
215 {
216 	struct rb_node *nd;
217 	struct symbol *curr, *next;
218 
219 	if (symbol_conf.allow_aliases)
220 		return;
221 
222 	nd = rb_first_cached(symbols);
223 
224 	while (nd) {
225 		curr = rb_entry(nd, struct symbol, rb_node);
226 again:
227 		nd = rb_next(&curr->rb_node);
228 		if (!nd)
229 			break;
230 
231 		next = rb_entry(nd, struct symbol, rb_node);
232 		if (curr->start != next->start)
233 			continue;
234 
235 		if (choose_best_symbol(curr, next) == SYMBOL_A) {
236 			if (next->type == STT_GNU_IFUNC)
237 				curr->ifunc_alias = true;
238 			rb_erase_cached(&next->rb_node, symbols);
239 			symbol__delete(next);
240 			goto again;
241 		} else {
242 			if (curr->type == STT_GNU_IFUNC)
243 				next->ifunc_alias = true;
244 			nd = rb_next(&curr->rb_node);
245 			rb_erase_cached(&curr->rb_node, symbols);
246 			symbol__delete(curr);
247 		}
248 	}
249 }
250 
251 /* Update zero-sized symbols using the address of the next symbol */
252 void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
253 {
254 	struct rb_node *nd, *prevnd = rb_first_cached(symbols);
255 	struct symbol *curr, *prev;
256 
257 	if (prevnd == NULL)
258 		return;
259 
260 	curr = rb_entry(prevnd, struct symbol, rb_node);
261 
262 	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
263 		prev = curr;
264 		curr = rb_entry(nd, struct symbol, rb_node);
265 
266 		/*
267 		 * On some architecture kernel text segment start is located at
268 		 * some low memory address, while modules are located at high
269 		 * memory addresses (or vice versa).  The gap between end of
270 		 * kernel text segment and beginning of first module's text
271 		 * segment is very big.  Therefore do not fill this gap and do
272 		 * not assign it to the kernel dso map (kallsyms).
273 		 *
274 		 * Also BPF code can be allocated separately from text segments
275 		 * and modules.  So the last entry in a module should not fill
276 		 * the gap too.
277 		 *
278 		 * In kallsyms, it determines module symbols using '[' character
279 		 * like in:
280 		 *   ffffffffc1937000 T hdmi_driver_init  [snd_hda_codec_hdmi]
281 		 */
282 		if (prev->end == prev->start) {
283 			const char *prev_mod;
284 			const char *curr_mod;
285 
286 			if (!is_kallsyms) {
287 				prev->end = curr->start;
288 				continue;
289 			}
290 
291 			prev_mod = strchr(prev->name, '[');
292 			curr_mod = strchr(curr->name, '[');
293 
294 			/* Last kernel/module symbol mapped to end of page */
295 			if (!prev_mod != !curr_mod)
296 				prev->end = roundup(prev->end + 4096, 4096);
297 			/* Last symbol in the previous module */
298 			else if (prev_mod && strcmp(prev_mod, curr_mod))
299 				prev->end = roundup(prev->end + 4096, 4096);
300 			else
301 				prev->end = curr->start;
302 
303 			pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
304 				  __func__, prev->name, prev->end);
305 		}
306 	}
307 
308 	/* Last entry */
309 	if (curr->end == curr->start)
310 		curr->end = roundup(curr->start, 4096) + 4096;
311 }
312 
313 struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
314 {
315 	size_t namelen = strlen(name) + 1;
316 	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
317 					sizeof(*sym) + namelen));
318 	if (sym == NULL)
319 		return NULL;
320 
321 	if (symbol_conf.priv_size) {
322 		if (symbol_conf.init_annotation) {
323 			struct annotation *notes = (void *)sym;
324 			annotation__init(notes);
325 		}
326 		sym = ((void *)sym) + symbol_conf.priv_size;
327 	}
328 
329 	sym->start   = start;
330 	sym->end     = len ? start + len : start;
331 	sym->type    = type;
332 	sym->binding = binding;
333 	sym->namelen = namelen - 1;
334 
335 	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
336 		  __func__, name, start, sym->end);
337 	memcpy(sym->name, name, namelen);
338 
339 	return sym;
340 }
341 
342 void symbol__delete(struct symbol *sym)
343 {
344 	if (symbol_conf.priv_size) {
345 		if (symbol_conf.init_annotation) {
346 			struct annotation *notes = symbol__annotation(sym);
347 
348 			annotation__exit(notes);
349 		}
350 	}
351 	free(((void *)sym) - symbol_conf.priv_size);
352 }
353 
354 void symbols__delete(struct rb_root_cached *symbols)
355 {
356 	struct symbol *pos;
357 	struct rb_node *next = rb_first_cached(symbols);
358 
359 	while (next) {
360 		pos = rb_entry(next, struct symbol, rb_node);
361 		next = rb_next(&pos->rb_node);
362 		rb_erase_cached(&pos->rb_node, symbols);
363 		symbol__delete(pos);
364 	}
365 }
366 
367 void __symbols__insert(struct rb_root_cached *symbols,
368 		       struct symbol *sym, bool kernel)
369 {
370 	struct rb_node **p = &symbols->rb_root.rb_node;
371 	struct rb_node *parent = NULL;
372 	const u64 ip = sym->start;
373 	struct symbol *s;
374 	bool leftmost = true;
375 
376 	if (kernel) {
377 		const char *name = sym->name;
378 		/*
379 		 * ppc64 uses function descriptors and appends a '.' to the
380 		 * start of every instruction address. Remove it.
381 		 */
382 		if (name[0] == '.')
383 			name++;
384 		sym->idle = symbol__is_idle(name);
385 	}
386 
387 	while (*p != NULL) {
388 		parent = *p;
389 		s = rb_entry(parent, struct symbol, rb_node);
390 		if (ip < s->start)
391 			p = &(*p)->rb_left;
392 		else {
393 			p = &(*p)->rb_right;
394 			leftmost = false;
395 		}
396 	}
397 	rb_link_node(&sym->rb_node, parent, p);
398 	rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
399 }
400 
401 void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
402 {
403 	__symbols__insert(symbols, sym, false);
404 }
405 
406 static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
407 {
408 	struct rb_node *n;
409 
410 	if (symbols == NULL)
411 		return NULL;
412 
413 	n = symbols->rb_root.rb_node;
414 
415 	while (n) {
416 		struct symbol *s = rb_entry(n, struct symbol, rb_node);
417 
418 		if (ip < s->start)
419 			n = n->rb_left;
420 		else if (ip > s->end || (ip == s->end && ip != s->start))
421 			n = n->rb_right;
422 		else
423 			return s;
424 	}
425 
426 	return NULL;
427 }
428 
429 static struct symbol *symbols__first(struct rb_root_cached *symbols)
430 {
431 	struct rb_node *n = rb_first_cached(symbols);
432 
433 	if (n)
434 		return rb_entry(n, struct symbol, rb_node);
435 
436 	return NULL;
437 }
438 
439 static struct symbol *symbols__last(struct rb_root_cached *symbols)
440 {
441 	struct rb_node *n = rb_last(&symbols->rb_root);
442 
443 	if (n)
444 		return rb_entry(n, struct symbol, rb_node);
445 
446 	return NULL;
447 }
448 
449 static struct symbol *symbols__next(struct symbol *sym)
450 {
451 	struct rb_node *n = rb_next(&sym->rb_node);
452 
453 	if (n)
454 		return rb_entry(n, struct symbol, rb_node);
455 
456 	return NULL;
457 }
458 
459 static int symbols__sort_name_cmp(const void *vlhs, const void *vrhs)
460 {
461 	const struct symbol *lhs = *((const struct symbol **)vlhs);
462 	const struct symbol *rhs = *((const struct symbol **)vrhs);
463 
464 	return strcmp(lhs->name, rhs->name);
465 }
466 
467 static struct symbol **symbols__sort_by_name(struct rb_root_cached *source, size_t *len)
468 {
469 	struct rb_node *nd;
470 	struct symbol **result;
471 	size_t i = 0, size = 0;
472 
473 	for (nd = rb_first_cached(source); nd; nd = rb_next(nd))
474 		size++;
475 
476 	result = malloc(sizeof(*result) * size);
477 	if (!result)
478 		return NULL;
479 
480 	for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
481 		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
482 
483 		result[i++] = pos;
484 	}
485 	qsort(result, size, sizeof(*result), symbols__sort_name_cmp);
486 	*len = size;
487 	return result;
488 }
489 
490 int symbol__match_symbol_name(const char *name, const char *str,
491 			      enum symbol_tag_include includes)
492 {
493 	const char *versioning;
494 
495 	if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
496 	    (versioning = strstr(name, "@@"))) {
497 		int len = strlen(str);
498 
499 		if (len < versioning - name)
500 			len = versioning - name;
501 
502 		return arch__compare_symbol_names_n(name, str, len);
503 	} else
504 		return arch__compare_symbol_names(name, str);
505 }
506 
507 static struct symbol *symbols__find_by_name(struct symbol *symbols[],
508 					    size_t symbols_len,
509 					    const char *name,
510 					    enum symbol_tag_include includes,
511 					    size_t *found_idx)
512 {
513 	size_t i, lower = 0, upper = symbols_len;
514 	struct symbol *s = NULL;
515 
516 	if (found_idx)
517 		*found_idx = SIZE_MAX;
518 
519 	if (!symbols_len)
520 		return NULL;
521 
522 	while (lower < upper) {
523 		int cmp;
524 
525 		i = (lower + upper) / 2;
526 		cmp = symbol__match_symbol_name(symbols[i]->name, name, includes);
527 
528 		if (cmp > 0)
529 			upper = i;
530 		else if (cmp < 0)
531 			lower = i + 1;
532 		else {
533 			if (found_idx)
534 				*found_idx = i;
535 			s = symbols[i];
536 			break;
537 		}
538 	}
539 	if (s && includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY) {
540 		/* return first symbol that has same name (if any) */
541 		for (; i > 0; i--) {
542 			struct symbol *tmp = symbols[i - 1];
543 
544 			if (!arch__compare_symbol_names(tmp->name, s->name)) {
545 				if (found_idx)
546 					*found_idx = i - 1;
547 				s = tmp;
548 			} else
549 				break;
550 		}
551 	}
552 	assert(!found_idx || !s || s == symbols[*found_idx]);
553 	return s;
554 }
555 
556 void dso__reset_find_symbol_cache(struct dso *dso)
557 {
558 	dso__set_last_find_result_addr(dso, 0);
559 	dso__set_last_find_result_symbol(dso, NULL);
560 }
561 
562 void dso__insert_symbol(struct dso *dso, struct symbol *sym)
563 {
564 	__symbols__insert(dso__symbols(dso), sym, dso__kernel(dso));
565 
566 	/* update the symbol cache if necessary */
567 	if (dso__last_find_result_addr(dso) >= sym->start &&
568 	    (dso__last_find_result_addr(dso) < sym->end ||
569 	    sym->start == sym->end)) {
570 		dso__set_last_find_result_symbol(dso, sym);
571 	}
572 }
573 
574 void dso__delete_symbol(struct dso *dso, struct symbol *sym)
575 {
576 	rb_erase_cached(&sym->rb_node, dso__symbols(dso));
577 	symbol__delete(sym);
578 	dso__reset_find_symbol_cache(dso);
579 }
580 
581 struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
582 {
583 	if (dso__last_find_result_addr(dso) != addr || dso__last_find_result_symbol(dso) == NULL) {
584 		dso__set_last_find_result_addr(dso, addr);
585 		dso__set_last_find_result_symbol(dso, symbols__find(dso__symbols(dso), addr));
586 	}
587 
588 	return dso__last_find_result_symbol(dso);
589 }
590 
591 struct symbol *dso__find_symbol_nocache(struct dso *dso, u64 addr)
592 {
593 	return symbols__find(dso__symbols(dso), addr);
594 }
595 
596 struct symbol *dso__first_symbol(struct dso *dso)
597 {
598 	return symbols__first(dso__symbols(dso));
599 }
600 
601 struct symbol *dso__last_symbol(struct dso *dso)
602 {
603 	return symbols__last(dso__symbols(dso));
604 }
605 
606 struct symbol *dso__next_symbol(struct symbol *sym)
607 {
608 	return symbols__next(sym);
609 }
610 
611 struct symbol *dso__next_symbol_by_name(struct dso *dso, size_t *idx)
612 {
613 	if (*idx + 1 >= dso__symbol_names_len(dso))
614 		return NULL;
615 
616 	++*idx;
617 	return dso__symbol_names(dso)[*idx];
618 }
619 
620  /*
621   * Returns first symbol that matched with @name.
622   */
623 struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name, size_t *idx)
624 {
625 	struct symbol *s = symbols__find_by_name(dso__symbol_names(dso),
626 						 dso__symbol_names_len(dso),
627 						 name, SYMBOL_TAG_INCLUDE__NONE, idx);
628 	if (!s) {
629 		s = symbols__find_by_name(dso__symbol_names(dso), dso__symbol_names_len(dso),
630 					  name, SYMBOL_TAG_INCLUDE__DEFAULT_ONLY, idx);
631 	}
632 	return s;
633 }
634 
635 void dso__sort_by_name(struct dso *dso)
636 {
637 	mutex_lock(dso__lock(dso));
638 	if (!dso__sorted_by_name(dso)) {
639 		size_t len = 0;
640 
641 		dso__set_symbol_names(dso, symbols__sort_by_name(dso__symbols(dso), &len));
642 		if (dso__symbol_names(dso)) {
643 			dso__set_symbol_names_len(dso, len);
644 			dso__set_sorted_by_name(dso);
645 		}
646 	}
647 	mutex_unlock(dso__lock(dso));
648 }
649 
650 /*
651  * While we find nice hex chars, build a long_val.
652  * Return number of chars processed.
653  */
654 static int hex2u64(const char *ptr, u64 *long_val)
655 {
656 	char *p;
657 
658 	*long_val = strtoull(ptr, &p, 16);
659 
660 	return p - ptr;
661 }
662 
663 
664 int modules__parse(const char *filename, void *arg,
665 		   int (*process_module)(void *arg, const char *name,
666 					 u64 start, u64 size))
667 {
668 	char *line = NULL;
669 	size_t n;
670 	FILE *file;
671 	int err = 0;
672 
673 	file = fopen(filename, "r");
674 	if (file == NULL)
675 		return -1;
676 
677 	while (1) {
678 		char name[PATH_MAX];
679 		u64 start, size;
680 		char *sep, *endptr;
681 		ssize_t line_len;
682 
683 		line_len = getline(&line, &n, file);
684 		if (line_len < 0) {
685 			if (feof(file))
686 				break;
687 			err = -1;
688 			goto out;
689 		}
690 
691 		if (!line) {
692 			err = -1;
693 			goto out;
694 		}
695 
696 		line[--line_len] = '\0'; /* \n */
697 
698 		sep = strrchr(line, 'x');
699 		if (sep == NULL)
700 			continue;
701 
702 		hex2u64(sep + 1, &start);
703 
704 		sep = strchr(line, ' ');
705 		if (sep == NULL)
706 			continue;
707 
708 		*sep = '\0';
709 
710 		scnprintf(name, sizeof(name), "[%s]", line);
711 
712 		size = strtoul(sep + 1, &endptr, 0);
713 		if (*endptr != ' ' && *endptr != '\t')
714 			continue;
715 
716 		err = process_module(arg, name, start, size);
717 		if (err)
718 			break;
719 	}
720 out:
721 	free(line);
722 	fclose(file);
723 	return err;
724 }
725 
726 /*
727  * These are symbols in the kernel image, so make sure that
728  * sym is from a kernel DSO.
729  */
730 static bool symbol__is_idle(const char *name)
731 {
732 	const char * const idle_symbols[] = {
733 		"acpi_idle_do_entry",
734 		"acpi_processor_ffh_cstate_enter",
735 		"arch_cpu_idle",
736 		"cpu_idle",
737 		"cpu_startup_entry",
738 		"idle_cpu",
739 		"intel_idle",
740 		"intel_idle_ibrs",
741 		"default_idle",
742 		"native_safe_halt",
743 		"enter_idle",
744 		"exit_idle",
745 		"mwait_idle",
746 		"mwait_idle_with_hints",
747 		"mwait_idle_with_hints.constprop.0",
748 		"poll_idle",
749 		"ppc64_runlatch_off",
750 		"pseries_dedicated_idle_sleep",
751 		"psw_idle",
752 		"psw_idle_exit",
753 		NULL
754 	};
755 	int i;
756 	static struct strlist *idle_symbols_list;
757 
758 	if (idle_symbols_list)
759 		return strlist__has_entry(idle_symbols_list, name);
760 
761 	idle_symbols_list = strlist__new(NULL, NULL);
762 
763 	for (i = 0; idle_symbols[i]; i++)
764 		strlist__add(idle_symbols_list, idle_symbols[i]);
765 
766 	return strlist__has_entry(idle_symbols_list, name);
767 }
768 
769 static int map__process_kallsym_symbol(void *arg, const char *name,
770 				       char type, u64 start)
771 {
772 	struct symbol *sym;
773 	struct dso *dso = arg;
774 	struct rb_root_cached *root = dso__symbols(dso);
775 
776 	if (!symbol_type__filter(type))
777 		return 0;
778 
779 	/* Ignore local symbols for ARM modules */
780 	if (name[0] == '$')
781 		return 0;
782 
783 	/*
784 	 * module symbols are not sorted so we add all
785 	 * symbols, setting length to 0, and rely on
786 	 * symbols__fixup_end() to fix it up.
787 	 */
788 	sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
789 	if (sym == NULL)
790 		return -ENOMEM;
791 	/*
792 	 * We will pass the symbols to the filter later, in
793 	 * map__split_kallsyms, when we have split the maps per module
794 	 */
795 	__symbols__insert(root, sym, !strchr(name, '['));
796 
797 	return 0;
798 }
799 
800 /*
801  * Loads the function entries in /proc/kallsyms into kernel_map->dso,
802  * so that we can in the next step set the symbol ->end address and then
803  * call kernel_maps__split_kallsyms.
804  */
805 static int dso__load_all_kallsyms(struct dso *dso, const char *filename)
806 {
807 	return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
808 }
809 
810 static int maps__split_kallsyms_for_kcore(struct maps *kmaps, struct dso *dso)
811 {
812 	struct symbol *pos;
813 	int count = 0;
814 	struct rb_root_cached *root = dso__symbols(dso);
815 	struct rb_root_cached old_root = *root;
816 	struct rb_node *next = rb_first_cached(root);
817 
818 	if (!kmaps)
819 		return -1;
820 
821 	*root = RB_ROOT_CACHED;
822 
823 	while (next) {
824 		struct map *curr_map;
825 		struct dso *curr_map_dso;
826 		char *module;
827 
828 		pos = rb_entry(next, struct symbol, rb_node);
829 		next = rb_next(&pos->rb_node);
830 
831 		rb_erase_cached(&pos->rb_node, &old_root);
832 		RB_CLEAR_NODE(&pos->rb_node);
833 		module = strchr(pos->name, '\t');
834 		if (module)
835 			*module = '\0';
836 
837 		curr_map = maps__find(kmaps, pos->start);
838 
839 		if (!curr_map) {
840 			symbol__delete(pos);
841 			continue;
842 		}
843 		curr_map_dso = map__dso(curr_map);
844 		pos->start -= map__start(curr_map) - map__pgoff(curr_map);
845 		if (pos->end > map__end(curr_map))
846 			pos->end = map__end(curr_map);
847 		if (pos->end)
848 			pos->end -= map__start(curr_map) - map__pgoff(curr_map);
849 		symbols__insert(dso__symbols(curr_map_dso), pos);
850 		++count;
851 		map__put(curr_map);
852 	}
853 
854 	/* Symbols have been adjusted */
855 	dso__set_adjust_symbols(dso, true);
856 
857 	return count;
858 }
859 
860 /*
861  * Split the symbols into maps, making sure there are no overlaps, i.e. the
862  * kernel range is broken in several maps, named [kernel].N, as we don't have
863  * the original ELF section names vmlinux have.
864  */
865 static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta,
866 				struct map *initial_map)
867 {
868 	struct machine *machine;
869 	struct map *curr_map = map__get(initial_map);
870 	struct symbol *pos;
871 	int count = 0, moved = 0;
872 	struct rb_root_cached *root = dso__symbols(dso);
873 	struct rb_node *next = rb_first_cached(root);
874 	int kernel_range = 0;
875 	bool x86_64;
876 
877 	if (!kmaps)
878 		return -1;
879 
880 	machine = maps__machine(kmaps);
881 
882 	x86_64 = machine__is(machine, "x86_64");
883 
884 	while (next) {
885 		char *module;
886 
887 		pos = rb_entry(next, struct symbol, rb_node);
888 		next = rb_next(&pos->rb_node);
889 
890 		module = strchr(pos->name, '\t');
891 		if (module) {
892 			struct dso *curr_map_dso;
893 
894 			if (!symbol_conf.use_modules)
895 				goto discard_symbol;
896 
897 			*module++ = '\0';
898 			curr_map_dso = map__dso(curr_map);
899 			if (strcmp(dso__short_name(curr_map_dso), module)) {
900 				if (!RC_CHK_EQUAL(curr_map, initial_map) &&
901 				    dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST &&
902 				    machine__is_default_guest(machine)) {
903 					/*
904 					 * We assume all symbols of a module are
905 					 * continuous in * kallsyms, so curr_map
906 					 * points to a module and all its
907 					 * symbols are in its kmap. Mark it as
908 					 * loaded.
909 					 */
910 					dso__set_loaded(curr_map_dso);
911 				}
912 
913 				map__zput(curr_map);
914 				curr_map = maps__find_by_name(kmaps, module);
915 				if (curr_map == NULL) {
916 					pr_debug("%s/proc/{kallsyms,modules} "
917 					         "inconsistency while looking "
918 						 "for \"%s\" module!\n",
919 						 machine->root_dir, module);
920 					curr_map = map__get(initial_map);
921 					goto discard_symbol;
922 				}
923 				curr_map_dso = map__dso(curr_map);
924 				if (dso__loaded(curr_map_dso) &&
925 				    !machine__is_default_guest(machine))
926 					goto discard_symbol;
927 			}
928 			/*
929 			 * So that we look just like we get from .ko files,
930 			 * i.e. not prelinked, relative to initial_map->start.
931 			 */
932 			pos->start = map__map_ip(curr_map, pos->start);
933 			pos->end   = map__map_ip(curr_map, pos->end);
934 		} else if (x86_64 && is_entry_trampoline(pos->name)) {
935 			/*
936 			 * These symbols are not needed anymore since the
937 			 * trampoline maps refer to the text section and it's
938 			 * symbols instead. Avoid having to deal with
939 			 * relocations, and the assumption that the first symbol
940 			 * is the start of kernel text, by simply removing the
941 			 * symbols at this point.
942 			 */
943 			goto discard_symbol;
944 		} else if (!RC_CHK_EQUAL(curr_map, initial_map)) {
945 			char dso_name[PATH_MAX];
946 			struct dso *ndso;
947 
948 			if (delta) {
949 				/* Kernel was relocated at boot time */
950 				pos->start -= delta;
951 				pos->end -= delta;
952 			}
953 
954 			if (count == 0) {
955 				map__zput(curr_map);
956 				curr_map = map__get(initial_map);
957 				goto add_symbol;
958 			}
959 
960 			if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
961 				snprintf(dso_name, sizeof(dso_name),
962 					"[guest.kernel].%d",
963 					kernel_range++);
964 			else
965 				snprintf(dso_name, sizeof(dso_name),
966 					"[kernel].%d",
967 					kernel_range++);
968 
969 			ndso = dso__new(dso_name);
970 			map__zput(curr_map);
971 			if (ndso == NULL)
972 				return -1;
973 
974 			dso__set_kernel(ndso, dso__kernel(dso));
975 
976 			curr_map = map__new2(pos->start, ndso);
977 			if (curr_map == NULL) {
978 				dso__put(ndso);
979 				return -1;
980 			}
981 
982 			map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY);
983 			if (maps__insert(kmaps, curr_map)) {
984 				map__zput(curr_map);
985 				dso__put(ndso);
986 				return -1;
987 			}
988 			++kernel_range;
989 		} else if (delta) {
990 			/* Kernel was relocated at boot time */
991 			pos->start -= delta;
992 			pos->end -= delta;
993 		}
994 add_symbol:
995 		if (!RC_CHK_EQUAL(curr_map, initial_map)) {
996 			struct dso *curr_map_dso = map__dso(curr_map);
997 
998 			rb_erase_cached(&pos->rb_node, root);
999 			symbols__insert(dso__symbols(curr_map_dso), pos);
1000 			++moved;
1001 		} else
1002 			++count;
1003 
1004 		continue;
1005 discard_symbol:
1006 		rb_erase_cached(&pos->rb_node, root);
1007 		symbol__delete(pos);
1008 	}
1009 
1010 	if (!RC_CHK_EQUAL(curr_map, initial_map) &&
1011 	    dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST &&
1012 	    machine__is_default_guest(maps__machine(kmaps))) {
1013 		dso__set_loaded(map__dso(curr_map));
1014 	}
1015 	map__put(curr_map);
1016 	return count + moved;
1017 }
1018 
1019 bool symbol__restricted_filename(const char *filename,
1020 				 const char *restricted_filename)
1021 {
1022 	bool restricted = false;
1023 
1024 	if (symbol_conf.kptr_restrict) {
1025 		char *r = realpath(filename, NULL);
1026 
1027 		if (r != NULL) {
1028 			restricted = strcmp(r, restricted_filename) == 0;
1029 			free(r);
1030 			return restricted;
1031 		}
1032 	}
1033 
1034 	return restricted;
1035 }
1036 
1037 struct module_info {
1038 	struct rb_node rb_node;
1039 	char *name;
1040 	u64 start;
1041 };
1042 
1043 static void add_module(struct module_info *mi, struct rb_root *modules)
1044 {
1045 	struct rb_node **p = &modules->rb_node;
1046 	struct rb_node *parent = NULL;
1047 	struct module_info *m;
1048 
1049 	while (*p != NULL) {
1050 		parent = *p;
1051 		m = rb_entry(parent, struct module_info, rb_node);
1052 		if (strcmp(mi->name, m->name) < 0)
1053 			p = &(*p)->rb_left;
1054 		else
1055 			p = &(*p)->rb_right;
1056 	}
1057 	rb_link_node(&mi->rb_node, parent, p);
1058 	rb_insert_color(&mi->rb_node, modules);
1059 }
1060 
1061 static void delete_modules(struct rb_root *modules)
1062 {
1063 	struct module_info *mi;
1064 	struct rb_node *next = rb_first(modules);
1065 
1066 	while (next) {
1067 		mi = rb_entry(next, struct module_info, rb_node);
1068 		next = rb_next(&mi->rb_node);
1069 		rb_erase(&mi->rb_node, modules);
1070 		zfree(&mi->name);
1071 		free(mi);
1072 	}
1073 }
1074 
1075 static struct module_info *find_module(const char *name,
1076 				       struct rb_root *modules)
1077 {
1078 	struct rb_node *n = modules->rb_node;
1079 
1080 	while (n) {
1081 		struct module_info *m;
1082 		int cmp;
1083 
1084 		m = rb_entry(n, struct module_info, rb_node);
1085 		cmp = strcmp(name, m->name);
1086 		if (cmp < 0)
1087 			n = n->rb_left;
1088 		else if (cmp > 0)
1089 			n = n->rb_right;
1090 		else
1091 			return m;
1092 	}
1093 
1094 	return NULL;
1095 }
1096 
1097 static int __read_proc_modules(void *arg, const char *name, u64 start,
1098 			       u64 size __maybe_unused)
1099 {
1100 	struct rb_root *modules = arg;
1101 	struct module_info *mi;
1102 
1103 	mi = zalloc(sizeof(struct module_info));
1104 	if (!mi)
1105 		return -ENOMEM;
1106 
1107 	mi->name = strdup(name);
1108 	mi->start = start;
1109 
1110 	if (!mi->name) {
1111 		free(mi);
1112 		return -ENOMEM;
1113 	}
1114 
1115 	add_module(mi, modules);
1116 
1117 	return 0;
1118 }
1119 
1120 static int read_proc_modules(const char *filename, struct rb_root *modules)
1121 {
1122 	if (symbol__restricted_filename(filename, "/proc/modules"))
1123 		return -1;
1124 
1125 	if (modules__parse(filename, modules, __read_proc_modules)) {
1126 		delete_modules(modules);
1127 		return -1;
1128 	}
1129 
1130 	return 0;
1131 }
1132 
1133 int compare_proc_modules(const char *from, const char *to)
1134 {
1135 	struct rb_root from_modules = RB_ROOT;
1136 	struct rb_root to_modules = RB_ROOT;
1137 	struct rb_node *from_node, *to_node;
1138 	struct module_info *from_m, *to_m;
1139 	int ret = -1;
1140 
1141 	if (read_proc_modules(from, &from_modules))
1142 		return -1;
1143 
1144 	if (read_proc_modules(to, &to_modules))
1145 		goto out_delete_from;
1146 
1147 	from_node = rb_first(&from_modules);
1148 	to_node = rb_first(&to_modules);
1149 	while (from_node) {
1150 		if (!to_node)
1151 			break;
1152 
1153 		from_m = rb_entry(from_node, struct module_info, rb_node);
1154 		to_m = rb_entry(to_node, struct module_info, rb_node);
1155 
1156 		if (from_m->start != to_m->start ||
1157 		    strcmp(from_m->name, to_m->name))
1158 			break;
1159 
1160 		from_node = rb_next(from_node);
1161 		to_node = rb_next(to_node);
1162 	}
1163 
1164 	if (!from_node && !to_node)
1165 		ret = 0;
1166 
1167 	delete_modules(&to_modules);
1168 out_delete_from:
1169 	delete_modules(&from_modules);
1170 
1171 	return ret;
1172 }
1173 
1174 static int do_validate_kcore_modules_cb(struct map *old_map, void *data)
1175 {
1176 	struct rb_root *modules = data;
1177 	struct module_info *mi;
1178 	struct dso *dso;
1179 
1180 	if (!__map__is_kmodule(old_map))
1181 		return 0;
1182 
1183 	dso = map__dso(old_map);
1184 	/* Module must be in memory at the same address */
1185 	mi = find_module(dso__short_name(dso), modules);
1186 	if (!mi || mi->start != map__start(old_map))
1187 		return -EINVAL;
1188 
1189 	return 0;
1190 }
1191 
1192 static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
1193 {
1194 	struct rb_root modules = RB_ROOT;
1195 	int err;
1196 
1197 	err = read_proc_modules(filename, &modules);
1198 	if (err)
1199 		return err;
1200 
1201 	err = maps__for_each_map(kmaps, do_validate_kcore_modules_cb, &modules);
1202 
1203 	delete_modules(&modules);
1204 	return err;
1205 }
1206 
1207 /*
1208  * If kallsyms is referenced by name then we look for filename in the same
1209  * directory.
1210  */
1211 static bool filename_from_kallsyms_filename(char *filename,
1212 					    const char *base_name,
1213 					    const char *kallsyms_filename)
1214 {
1215 	char *name;
1216 
1217 	strcpy(filename, kallsyms_filename);
1218 	name = strrchr(filename, '/');
1219 	if (!name)
1220 		return false;
1221 
1222 	name += 1;
1223 
1224 	if (!strcmp(name, "kallsyms")) {
1225 		strcpy(name, base_name);
1226 		return true;
1227 	}
1228 
1229 	return false;
1230 }
1231 
1232 static int validate_kcore_modules(const char *kallsyms_filename,
1233 				  struct map *map)
1234 {
1235 	struct maps *kmaps = map__kmaps(map);
1236 	char modules_filename[PATH_MAX];
1237 
1238 	if (!kmaps)
1239 		return -EINVAL;
1240 
1241 	if (!filename_from_kallsyms_filename(modules_filename, "modules",
1242 					     kallsyms_filename))
1243 		return -EINVAL;
1244 
1245 	if (do_validate_kcore_modules(modules_filename, kmaps))
1246 		return -EINVAL;
1247 
1248 	return 0;
1249 }
1250 
1251 static int validate_kcore_addresses(const char *kallsyms_filename,
1252 				    struct map *map)
1253 {
1254 	struct kmap *kmap = map__kmap(map);
1255 
1256 	if (!kmap)
1257 		return -EINVAL;
1258 
1259 	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
1260 		u64 start;
1261 
1262 		if (kallsyms__get_function_start(kallsyms_filename,
1263 						 kmap->ref_reloc_sym->name, &start))
1264 			return -ENOENT;
1265 		if (start != kmap->ref_reloc_sym->addr)
1266 			return -EINVAL;
1267 	}
1268 
1269 	return validate_kcore_modules(kallsyms_filename, map);
1270 }
1271 
1272 struct kcore_mapfn_data {
1273 	struct dso *dso;
1274 	struct list_head maps;
1275 };
1276 
1277 static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
1278 {
1279 	struct kcore_mapfn_data *md = data;
1280 	struct map_list_node *list_node = map_list_node__new();
1281 
1282 	if (!list_node)
1283 		return -ENOMEM;
1284 
1285 	list_node->map = map__new2(start, md->dso);
1286 	if (!list_node->map) {
1287 		free(list_node);
1288 		return -ENOMEM;
1289 	}
1290 
1291 	map__set_end(list_node->map, map__start(list_node->map) + len);
1292 	map__set_pgoff(list_node->map, pgoff);
1293 
1294 	list_add(&list_node->node, &md->maps);
1295 
1296 	return 0;
1297 }
1298 
1299 static bool remove_old_maps(struct map *map, void *data)
1300 {
1301 	const struct map *map_to_save = data;
1302 
1303 	/*
1304 	 * We need to preserve eBPF maps even if they are covered by kcore,
1305 	 * because we need to access eBPF dso for source data.
1306 	 */
1307 	return !RC_CHK_EQUAL(map, map_to_save) && !__map__is_bpf_prog(map);
1308 }
1309 
1310 static int dso__load_kcore(struct dso *dso, struct map *map,
1311 			   const char *kallsyms_filename)
1312 {
1313 	struct maps *kmaps = map__kmaps(map);
1314 	struct kcore_mapfn_data md;
1315 	struct map *map_ref, *replacement_map = NULL;
1316 	struct machine *machine;
1317 	bool is_64_bit;
1318 	int err, fd;
1319 	char kcore_filename[PATH_MAX];
1320 	u64 stext;
1321 
1322 	if (!kmaps)
1323 		return -EINVAL;
1324 
1325 	machine = maps__machine(kmaps);
1326 
1327 	/* This function requires that the map is the kernel map */
1328 	if (!__map__is_kernel(map))
1329 		return -EINVAL;
1330 
1331 	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
1332 					     kallsyms_filename))
1333 		return -EINVAL;
1334 
1335 	/* Modules and kernel must be present at their original addresses */
1336 	if (validate_kcore_addresses(kallsyms_filename, map))
1337 		return -EINVAL;
1338 
1339 	md.dso = dso;
1340 	INIT_LIST_HEAD(&md.maps);
1341 
1342 	fd = open(kcore_filename, O_RDONLY);
1343 	if (fd < 0) {
1344 		pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
1345 			 kcore_filename);
1346 		return -EINVAL;
1347 	}
1348 
1349 	/* Read new maps into temporary lists */
1350 	err = file__read_maps(fd, map__prot(map) & PROT_EXEC, kcore_mapfn, &md,
1351 			      &is_64_bit);
1352 	if (err)
1353 		goto out_err;
1354 	dso__set_is_64_bit(dso, is_64_bit);
1355 
1356 	if (list_empty(&md.maps)) {
1357 		err = -EINVAL;
1358 		goto out_err;
1359 	}
1360 
1361 	/* Remove old maps */
1362 	maps__remove_maps(kmaps, remove_old_maps, map);
1363 	machine->trampolines_mapped = false;
1364 
1365 	/* Find the kernel map using the '_stext' symbol */
1366 	if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
1367 		u64 replacement_size = 0;
1368 		struct map_list_node *new_node;
1369 
1370 		list_for_each_entry(new_node, &md.maps, node) {
1371 			struct map *new_map = new_node->map;
1372 			u64 new_size = map__size(new_map);
1373 
1374 			if (!(stext >= map__start(new_map) && stext < map__end(new_map)))
1375 				continue;
1376 
1377 			/*
1378 			 * On some architectures, ARM64 for example, the kernel
1379 			 * text can get allocated inside of the vmalloc segment.
1380 			 * Select the smallest matching segment, in case stext
1381 			 * falls within more than one in the list.
1382 			 */
1383 			if (!replacement_map || new_size < replacement_size) {
1384 				replacement_map = new_map;
1385 				replacement_size = new_size;
1386 			}
1387 		}
1388 	}
1389 
1390 	if (!replacement_map)
1391 		replacement_map = list_entry(md.maps.next, struct map_list_node, node)->map;
1392 
1393 	/*
1394 	 * Update addresses of vmlinux map. Re-insert it to ensure maps are
1395 	 * correctly ordered. Do this before using maps__merge_in() for the
1396 	 * remaining maps so vmlinux gets split if necessary.
1397 	 */
1398 	map_ref = map__get(map);
1399 	maps__remove(kmaps, map_ref);
1400 
1401 	map__set_start(map_ref, map__start(replacement_map));
1402 	map__set_end(map_ref, map__end(replacement_map));
1403 	map__set_pgoff(map_ref, map__pgoff(replacement_map));
1404 	map__set_mapping_type(map_ref, map__mapping_type(replacement_map));
1405 
1406 	err = maps__insert(kmaps, map_ref);
1407 	map__put(map_ref);
1408 	if (err)
1409 		goto out_err;
1410 
1411 	/* Add new maps */
1412 	while (!list_empty(&md.maps)) {
1413 		struct map_list_node *new_node = list_entry(md.maps.next, struct map_list_node, node);
1414 		struct map *new_map = new_node->map;
1415 
1416 		list_del_init(&new_node->node);
1417 
1418 		/* skip if replacement_map, already inserted above */
1419 		if (!RC_CHK_EQUAL(new_map, replacement_map)) {
1420 			/*
1421 			 * Merge kcore map into existing maps,
1422 			 * and ensure that current maps (eBPF)
1423 			 * stay intact.
1424 			 */
1425 			if (maps__merge_in(kmaps, new_map)) {
1426 				err = -EINVAL;
1427 				goto out_err;
1428 			}
1429 		}
1430 		map__zput(new_node->map);
1431 		free(new_node);
1432 	}
1433 
1434 	if (machine__is(machine, "x86_64")) {
1435 		u64 addr;
1436 
1437 		/*
1438 		 * If one of the corresponding symbols is there, assume the
1439 		 * entry trampoline maps are too.
1440 		 */
1441 		if (!kallsyms__get_function_start(kallsyms_filename,
1442 						  ENTRY_TRAMPOLINE_NAME,
1443 						  &addr))
1444 			machine->trampolines_mapped = true;
1445 	}
1446 
1447 	/*
1448 	 * Set the data type and long name so that kcore can be read via
1449 	 * dso__data_read_addr().
1450 	 */
1451 	if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
1452 		dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_KCORE);
1453 	else
1454 		dso__set_binary_type(dso, DSO_BINARY_TYPE__KCORE);
1455 	dso__set_long_name(dso, strdup(kcore_filename), true);
1456 
1457 	close(fd);
1458 
1459 	if (map__prot(map) & PROT_EXEC)
1460 		pr_debug("Using %s for kernel object code\n", kcore_filename);
1461 	else
1462 		pr_debug("Using %s for kernel data\n", kcore_filename);
1463 
1464 	return 0;
1465 
1466 out_err:
1467 	while (!list_empty(&md.maps)) {
1468 		struct map_list_node *list_node;
1469 
1470 		list_node = list_entry(md.maps.next, struct map_list_node, node);
1471 		list_del_init(&list_node->node);
1472 		map__zput(list_node->map);
1473 		free(list_node);
1474 	}
1475 	close(fd);
1476 	return err;
1477 }
1478 
1479 /*
1480  * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
1481  * delta based on the relocation reference symbol.
1482  */
1483 static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
1484 {
1485 	u64 addr;
1486 
1487 	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
1488 		return 0;
1489 
1490 	if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
1491 		return -1;
1492 
1493 	*delta = addr - kmap->ref_reloc_sym->addr;
1494 	return 0;
1495 }
1496 
1497 int __dso__load_kallsyms(struct dso *dso, const char *filename,
1498 			 struct map *map, bool no_kcore)
1499 {
1500 	struct kmap *kmap = map__kmap(map);
1501 	u64 delta = 0;
1502 
1503 	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
1504 		return -1;
1505 
1506 	if (!kmap || !kmap->kmaps)
1507 		return -1;
1508 
1509 	if (dso__load_all_kallsyms(dso, filename) < 0)
1510 		return -1;
1511 
1512 	if (kallsyms__delta(kmap, filename, &delta))
1513 		return -1;
1514 
1515 	symbols__fixup_end(dso__symbols(dso), true);
1516 	symbols__fixup_duplicate(dso__symbols(dso));
1517 
1518 	if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
1519 		dso__set_symtab_type(dso, DSO_BINARY_TYPE__GUEST_KALLSYMS);
1520 	else
1521 		dso__set_symtab_type(dso, DSO_BINARY_TYPE__KALLSYMS);
1522 
1523 	if (!no_kcore && !dso__load_kcore(dso, map, filename))
1524 		return maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
1525 	else
1526 		return maps__split_kallsyms(kmap->kmaps, dso, delta, map);
1527 }
1528 
1529 int dso__load_kallsyms(struct dso *dso, const char *filename,
1530 		       struct map *map)
1531 {
1532 	return __dso__load_kallsyms(dso, filename, map, false);
1533 }
1534 
1535 static int dso__load_perf_map(const char *map_path, struct dso *dso)
1536 {
1537 	char *line = NULL;
1538 	size_t n;
1539 	FILE *file;
1540 	int nr_syms = 0;
1541 
1542 	file = fopen(map_path, "r");
1543 	if (file == NULL)
1544 		goto out_failure;
1545 
1546 	while (!feof(file)) {
1547 		u64 start, size;
1548 		struct symbol *sym;
1549 		int line_len, len;
1550 
1551 		line_len = getline(&line, &n, file);
1552 		if (line_len < 0)
1553 			break;
1554 
1555 		if (!line)
1556 			goto out_failure;
1557 
1558 		line[--line_len] = '\0'; /* \n */
1559 
1560 		len = hex2u64(line, &start);
1561 
1562 		len++;
1563 		if (len + 2 >= line_len)
1564 			continue;
1565 
1566 		len += hex2u64(line + len, &size);
1567 
1568 		len++;
1569 		if (len + 2 >= line_len)
1570 			continue;
1571 
1572 		sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
1573 
1574 		if (sym == NULL)
1575 			goto out_delete_line;
1576 
1577 		symbols__insert(dso__symbols(dso), sym);
1578 		nr_syms++;
1579 	}
1580 
1581 	free(line);
1582 	fclose(file);
1583 
1584 	return nr_syms;
1585 
1586 out_delete_line:
1587 	free(line);
1588 out_failure:
1589 	return -1;
1590 }
1591 
1592 #ifdef HAVE_LIBBFD_SUPPORT
1593 #define PACKAGE 'perf'
1594 #include <bfd.h>
1595 
1596 static int bfd_symbols__cmpvalue(const void *a, const void *b)
1597 {
1598 	const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
1599 
1600 	if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
1601 		return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
1602 
1603 	return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
1604 }
1605 
1606 static int bfd2elf_binding(asymbol *symbol)
1607 {
1608 	if (symbol->flags & BSF_WEAK)
1609 		return STB_WEAK;
1610 	if (symbol->flags & BSF_GLOBAL)
1611 		return STB_GLOBAL;
1612 	if (symbol->flags & BSF_LOCAL)
1613 		return STB_LOCAL;
1614 	return -1;
1615 }
1616 
1617 int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
1618 {
1619 	int err = -1;
1620 	long symbols_size, symbols_count, i;
1621 	asection *section;
1622 	asymbol **symbols, *sym;
1623 	struct symbol *symbol;
1624 	bfd *abfd;
1625 	u64 start, len;
1626 
1627 	abfd = bfd_openr(debugfile, NULL);
1628 	if (!abfd)
1629 		return -1;
1630 
1631 	if (!bfd_check_format(abfd, bfd_object)) {
1632 		pr_debug2("%s: cannot read %s bfd file.\n", __func__,
1633 			  dso__long_name(dso));
1634 		goto out_close;
1635 	}
1636 
1637 	if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
1638 		goto out_close;
1639 
1640 	symbols_size = bfd_get_symtab_upper_bound(abfd);
1641 	if (symbols_size == 0) {
1642 		bfd_close(abfd);
1643 		return 0;
1644 	}
1645 
1646 	if (symbols_size < 0)
1647 		goto out_close;
1648 
1649 	symbols = malloc(symbols_size);
1650 	if (!symbols)
1651 		goto out_close;
1652 
1653 	symbols_count = bfd_canonicalize_symtab(abfd, symbols);
1654 	if (symbols_count < 0)
1655 		goto out_free;
1656 
1657 	section = bfd_get_section_by_name(abfd, ".text");
1658 	if (section) {
1659 		for (i = 0; i < symbols_count; ++i) {
1660 			if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
1661 			    !strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
1662 				break;
1663 		}
1664 		if (i < symbols_count) {
1665 			/* PE symbols can only have 4 bytes, so use .text high bits */
1666 			u64 text_offset = (section->vma - (u32)section->vma)
1667 				+ (u32)bfd_asymbol_value(symbols[i]);
1668 			dso__set_text_offset(dso, text_offset);
1669 			dso__set_text_end(dso, (section->vma - text_offset) + section->size);
1670 		} else {
1671 			dso__set_text_offset(dso, section->vma - section->filepos);
1672 			dso__set_text_end(dso, section->filepos + section->size);
1673 		}
1674 	}
1675 
1676 	qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
1677 
1678 #ifdef bfd_get_section
1679 #define bfd_asymbol_section bfd_get_section
1680 #endif
1681 	for (i = 0; i < symbols_count; ++i) {
1682 		sym = symbols[i];
1683 		section = bfd_asymbol_section(sym);
1684 		if (bfd2elf_binding(sym) < 0)
1685 			continue;
1686 
1687 		while (i + 1 < symbols_count &&
1688 		       bfd_asymbol_section(symbols[i + 1]) == section &&
1689 		       bfd2elf_binding(symbols[i + 1]) < 0)
1690 			i++;
1691 
1692 		if (i + 1 < symbols_count &&
1693 		    bfd_asymbol_section(symbols[i + 1]) == section)
1694 			len = symbols[i + 1]->value - sym->value;
1695 		else
1696 			len = section->size - sym->value;
1697 
1698 		start = bfd_asymbol_value(sym) - dso__text_offset(dso);
1699 		symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
1700 				     bfd_asymbol_name(sym));
1701 		if (!symbol)
1702 			goto out_free;
1703 
1704 		symbols__insert(dso__symbols(dso), symbol);
1705 	}
1706 #ifdef bfd_get_section
1707 #undef bfd_asymbol_section
1708 #endif
1709 
1710 	symbols__fixup_end(dso__symbols(dso), false);
1711 	symbols__fixup_duplicate(dso__symbols(dso));
1712 	dso__set_adjust_symbols(dso, true);
1713 
1714 	err = 0;
1715 out_free:
1716 	free(symbols);
1717 out_close:
1718 	bfd_close(abfd);
1719 	return err;
1720 }
1721 #endif
1722 
1723 static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
1724 					   enum dso_binary_type type)
1725 {
1726 	switch (type) {
1727 	case DSO_BINARY_TYPE__JAVA_JIT:
1728 	case DSO_BINARY_TYPE__DEBUGLINK:
1729 	case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
1730 	case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
1731 	case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
1732 	case DSO_BINARY_TYPE__MIXEDUP_UBUNTU_DEBUGINFO:
1733 	case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
1734 	case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
1735 	case DSO_BINARY_TYPE__GNU_DEBUGDATA:
1736 		return !kmod && dso__kernel(dso) == DSO_SPACE__USER;
1737 
1738 	case DSO_BINARY_TYPE__KALLSYMS:
1739 	case DSO_BINARY_TYPE__VMLINUX:
1740 	case DSO_BINARY_TYPE__KCORE:
1741 		return dso__kernel(dso) == DSO_SPACE__KERNEL;
1742 
1743 	case DSO_BINARY_TYPE__GUEST_KALLSYMS:
1744 	case DSO_BINARY_TYPE__GUEST_VMLINUX:
1745 	case DSO_BINARY_TYPE__GUEST_KCORE:
1746 		return dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST;
1747 
1748 	case DSO_BINARY_TYPE__GUEST_KMODULE:
1749 	case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
1750 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
1751 	case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
1752 		/*
1753 		 * kernel modules know their symtab type - it's set when
1754 		 * creating a module dso in machine__addnew_module_map().
1755 		 */
1756 		return kmod && dso__symtab_type(dso) == type;
1757 
1758 	case DSO_BINARY_TYPE__BUILD_ID_CACHE:
1759 	case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
1760 		return true;
1761 
1762 	case DSO_BINARY_TYPE__BPF_PROG_INFO:
1763 	case DSO_BINARY_TYPE__BPF_IMAGE:
1764 	case DSO_BINARY_TYPE__OOL:
1765 	case DSO_BINARY_TYPE__NOT_FOUND:
1766 	default:
1767 		return false;
1768 	}
1769 }
1770 
1771 /* Checks for the existence of the perf-<pid>.map file in two different
1772  * locations.  First, if the process is a separate mount namespace, check in
1773  * that namespace using the pid of the innermost pid namespace.  If's not in a
1774  * namespace, or the file can't be found there, try in the mount namespace of
1775  * the tracing process using our view of its pid.
1776  */
1777 static int dso__find_perf_map(char *filebuf, size_t bufsz,
1778 			      struct nsinfo **nsip)
1779 {
1780 	struct nscookie nsc;
1781 	struct nsinfo *nsi;
1782 	struct nsinfo *nnsi;
1783 	int rc = -1;
1784 
1785 	nsi = *nsip;
1786 
1787 	if (nsinfo__need_setns(nsi)) {
1788 		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
1789 		nsinfo__mountns_enter(nsi, &nsc);
1790 		rc = access(filebuf, R_OK);
1791 		nsinfo__mountns_exit(&nsc);
1792 		if (rc == 0)
1793 			return rc;
1794 	}
1795 
1796 	nnsi = nsinfo__copy(nsi);
1797 	if (nnsi) {
1798 		nsinfo__put(nsi);
1799 
1800 		nsinfo__clear_need_setns(nnsi);
1801 		snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
1802 		*nsip = nnsi;
1803 		rc = 0;
1804 	}
1805 
1806 	return rc;
1807 }
1808 
1809 int dso__load(struct dso *dso, struct map *map)
1810 {
1811 	char *name;
1812 	int ret = -1;
1813 	u_int i;
1814 	struct machine *machine = NULL;
1815 	char *root_dir = (char *) "";
1816 	int ss_pos = 0;
1817 	struct symsrc ss_[2];
1818 	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1819 	bool kmod;
1820 	bool perfmap;
1821 	struct nscookie nsc;
1822 	char newmapname[PATH_MAX];
1823 	const char *map_path = dso__long_name(dso);
1824 
1825 	mutex_lock(dso__lock(dso));
1826 	perfmap = is_perf_pid_map_name(map_path);
1827 
1828 	if (perfmap) {
1829 		if (dso__nsinfo(dso) &&
1830 		    (dso__find_perf_map(newmapname, sizeof(newmapname),
1831 					dso__nsinfo_ptr(dso)) == 0)) {
1832 			map_path = newmapname;
1833 		}
1834 	}
1835 
1836 	nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
1837 
1838 	/* check again under the dso->lock */
1839 	if (dso__loaded(dso)) {
1840 		ret = 1;
1841 		goto out;
1842 	}
1843 
1844 	kmod = dso__is_kmod(dso);
1845 
1846 	if (dso__kernel(dso) && !kmod) {
1847 		if (dso__kernel(dso) == DSO_SPACE__KERNEL)
1848 			ret = dso__load_kernel_sym(dso, map);
1849 		else if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
1850 			ret = dso__load_guest_kernel_sym(dso, map);
1851 
1852 		machine = maps__machine(map__kmaps(map));
1853 		if (machine__is(machine, "x86_64"))
1854 			machine__map_x86_64_entry_trampolines(machine, dso);
1855 		goto out;
1856 	}
1857 
1858 	dso__set_adjust_symbols(dso, false);
1859 
1860 	if (perfmap) {
1861 		ret = dso__load_perf_map(map_path, dso);
1862 		dso__set_symtab_type(dso, ret > 0
1863 				? DSO_BINARY_TYPE__JAVA_JIT
1864 				: DSO_BINARY_TYPE__NOT_FOUND);
1865 		goto out;
1866 	}
1867 
1868 	if (machine)
1869 		root_dir = machine->root_dir;
1870 
1871 	name = malloc(PATH_MAX);
1872 	if (!name)
1873 		goto out;
1874 
1875 	/*
1876 	 * Read the build id if possible. This is required for
1877 	 * DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work. Don't block in case path
1878 	 * isn't for a regular file.
1879 	 */
1880 	if (!dso__has_build_id(dso)) {
1881 		struct build_id bid = { .size = 0, };
1882 
1883 		__symbol__join_symfs(name, PATH_MAX, dso__long_name(dso));
1884 		if (filename__read_build_id(name, &bid, /*block=*/false) > 0)
1885 			dso__set_build_id(dso, &bid);
1886 	}
1887 
1888 	/*
1889 	 * Iterate over candidate debug images.
1890 	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
1891 	 * and/or opd section) for processing.
1892 	 */
1893 	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1894 		struct symsrc *ss = &ss_[ss_pos];
1895 		bool next_slot = false;
1896 		bool is_reg;
1897 		bool nsexit;
1898 		int bfdrc = -1;
1899 		int sirc = -1;
1900 
1901 		enum dso_binary_type symtab_type = binary_type_symtab[i];
1902 
1903 		nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
1904 		    symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
1905 
1906 		if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
1907 			continue;
1908 
1909 		if (dso__read_binary_type_filename(dso, symtab_type,
1910 						   root_dir, name, PATH_MAX))
1911 			continue;
1912 
1913 		if (nsexit)
1914 			nsinfo__mountns_exit(&nsc);
1915 
1916 		is_reg = is_regular_file(name);
1917 		if (!is_reg && errno == ENOENT && dso__nsinfo(dso)) {
1918 			char *new_name = dso__filename_with_chroot(dso, name);
1919 			if (new_name) {
1920 				is_reg = is_regular_file(new_name);
1921 				strlcpy(name, new_name, PATH_MAX);
1922 				free(new_name);
1923 			}
1924 		}
1925 
1926 #ifdef HAVE_LIBBFD_SUPPORT
1927 		if (is_reg)
1928 			bfdrc = dso__load_bfd_symbols(dso, name);
1929 #endif
1930 		if (is_reg && bfdrc < 0)
1931 			sirc = symsrc__init(ss, dso, name, symtab_type);
1932 
1933 		if (nsexit)
1934 			nsinfo__mountns_enter(dso__nsinfo(dso), &nsc);
1935 
1936 		if (bfdrc == 0) {
1937 			ret = 0;
1938 			break;
1939 		}
1940 
1941 		if (!is_reg || sirc < 0)
1942 			continue;
1943 
1944 		if (!syms_ss && symsrc__has_symtab(ss)) {
1945 			syms_ss = ss;
1946 			next_slot = true;
1947 			if (!dso__symsrc_filename(dso))
1948 				dso__set_symsrc_filename(dso, strdup(name));
1949 		}
1950 
1951 		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
1952 			runtime_ss = ss;
1953 			next_slot = true;
1954 		}
1955 
1956 		if (next_slot) {
1957 			ss_pos++;
1958 
1959 			if (dso__binary_type(dso) == DSO_BINARY_TYPE__NOT_FOUND)
1960 				dso__set_binary_type(dso, symtab_type);
1961 
1962 			if (syms_ss && runtime_ss)
1963 				break;
1964 		} else {
1965 			symsrc__destroy(ss);
1966 		}
1967 
1968 	}
1969 
1970 	if (!runtime_ss && !syms_ss)
1971 		goto out_free;
1972 
1973 	if (runtime_ss && !syms_ss) {
1974 		syms_ss = runtime_ss;
1975 	}
1976 
1977 	/* We'll have to hope for the best */
1978 	if (!runtime_ss && syms_ss)
1979 		runtime_ss = syms_ss;
1980 
1981 	if (syms_ss)
1982 		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
1983 	else
1984 		ret = -1;
1985 
1986 	if (ret > 0) {
1987 		int nr_plt;
1988 
1989 		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
1990 		if (nr_plt > 0)
1991 			ret += nr_plt;
1992 	}
1993 
1994 	for (; ss_pos > 0; ss_pos--)
1995 		symsrc__destroy(&ss_[ss_pos - 1]);
1996 out_free:
1997 	free(name);
1998 	if (ret < 0 && strstr(dso__name(dso), " (deleted)") != NULL)
1999 		ret = 0;
2000 out:
2001 	dso__set_loaded(dso);
2002 	mutex_unlock(dso__lock(dso));
2003 	nsinfo__mountns_exit(&nsc);
2004 
2005 	return ret;
2006 }
2007 
2008 /*
2009  * Always takes ownership of vmlinux when vmlinux_allocated == true, even if
2010  * it returns an error.
2011  */
2012 int dso__load_vmlinux(struct dso *dso, struct map *map,
2013 		      const char *vmlinux, bool vmlinux_allocated)
2014 {
2015 	int err = -1;
2016 	struct symsrc ss;
2017 	char symfs_vmlinux[PATH_MAX];
2018 	enum dso_binary_type symtab_type;
2019 
2020 	if (vmlinux[0] == '/')
2021 		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
2022 	else
2023 		symbol__join_symfs(symfs_vmlinux, vmlinux);
2024 
2025 	if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
2026 		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
2027 	else
2028 		symtab_type = DSO_BINARY_TYPE__VMLINUX;
2029 
2030 	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type)) {
2031 		if (vmlinux_allocated)
2032 			free((char *) vmlinux);
2033 		return -1;
2034 	}
2035 
2036 	/*
2037 	 * dso__load_sym() may copy 'dso' which will result in the copies having
2038 	 * an incorrect long name unless we set it here first.
2039 	 */
2040 	dso__set_long_name(dso, vmlinux, vmlinux_allocated);
2041 	if (dso__kernel(dso) == DSO_SPACE__KERNEL_GUEST)
2042 		dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_VMLINUX);
2043 	else
2044 		dso__set_binary_type(dso, DSO_BINARY_TYPE__VMLINUX);
2045 
2046 	err = dso__load_sym(dso, map, &ss, &ss, 0);
2047 	symsrc__destroy(&ss);
2048 
2049 	if (err > 0) {
2050 		dso__set_loaded(dso);
2051 		pr_debug("Using %s for symbols\n", symfs_vmlinux);
2052 	}
2053 
2054 	return err;
2055 }
2056 
2057 int dso__load_vmlinux_path(struct dso *dso, struct map *map)
2058 {
2059 	int i, err = 0;
2060 	char *filename = NULL;
2061 
2062 	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
2063 		 vmlinux_path__nr_entries + 1);
2064 
2065 	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
2066 		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
2067 		if (err > 0)
2068 			goto out;
2069 	}
2070 
2071 	if (!symbol_conf.ignore_vmlinux_buildid)
2072 		filename = dso__build_id_filename(dso, NULL, 0, false);
2073 	if (filename != NULL) {
2074 		err = dso__load_vmlinux(dso, map, filename, true);
2075 		if (err > 0)
2076 			goto out;
2077 	}
2078 out:
2079 	return err;
2080 }
2081 
2082 static bool visible_dir_filter(const char *name, struct dirent *d)
2083 {
2084 	if (d->d_type != DT_DIR)
2085 		return false;
2086 	return lsdir_no_dot_filter(name, d);
2087 }
2088 
2089 static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
2090 {
2091 	char kallsyms_filename[PATH_MAX];
2092 	int ret = -1;
2093 	struct strlist *dirs;
2094 	struct str_node *nd;
2095 
2096 	dirs = lsdir(dir, visible_dir_filter);
2097 	if (!dirs)
2098 		return -1;
2099 
2100 	strlist__for_each_entry(nd, dirs) {
2101 		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
2102 			  "%s/%s/kallsyms", dir, nd->s);
2103 		if (!validate_kcore_addresses(kallsyms_filename, map)) {
2104 			strlcpy(dir, kallsyms_filename, dir_sz);
2105 			ret = 0;
2106 			break;
2107 		}
2108 	}
2109 
2110 	strlist__delete(dirs);
2111 
2112 	return ret;
2113 }
2114 
2115 /*
2116  * Use open(O_RDONLY) to check readability directly instead of access(R_OK)
2117  * since access(R_OK) only checks with real UID/GID but open() use effective
2118  * UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
2119  */
2120 static bool filename__readable(const char *file)
2121 {
2122 	int fd = open(file, O_RDONLY);
2123 	if (fd < 0)
2124 		return false;
2125 	close(fd);
2126 	return true;
2127 }
2128 
2129 static char *dso__find_kallsyms(struct dso *dso, struct map *map)
2130 {
2131 	struct build_id bid = { .size = 0, };
2132 	char sbuild_id[SBUILD_ID_SIZE];
2133 	bool is_host = false;
2134 	char path[PATH_MAX];
2135 
2136 	if (!dso__has_build_id(dso)) {
2137 		/*
2138 		 * Last resort, if we don't have a build-id and couldn't find
2139 		 * any vmlinux file, try the running kernel kallsyms table.
2140 		 */
2141 		goto proc_kallsyms;
2142 	}
2143 
2144 	if (sysfs__read_build_id("/sys/kernel/notes", &bid) == 0)
2145 		is_host = dso__build_id_equal(dso, &bid);
2146 
2147 	/* Try a fast path for /proc/kallsyms if possible */
2148 	if (is_host) {
2149 		/*
2150 		 * Do not check the build-id cache, unless we know we cannot use
2151 		 * /proc/kcore or module maps don't match to /proc/kallsyms.
2152 		 * To check readability of /proc/kcore, do not use access(R_OK)
2153 		 * since /proc/kcore requires CAP_SYS_RAWIO to read and access
2154 		 * can't check it.
2155 		 */
2156 		if (filename__readable("/proc/kcore") &&
2157 		    !validate_kcore_addresses("/proc/kallsyms", map))
2158 			goto proc_kallsyms;
2159 	}
2160 
2161 	build_id__snprintf(dso__bid(dso), sbuild_id, sizeof(sbuild_id));
2162 
2163 	/* Find kallsyms in build-id cache with kcore */
2164 	scnprintf(path, sizeof(path), "%s/%s/%s",
2165 		  buildid_dir, DSO__NAME_KCORE, sbuild_id);
2166 
2167 	if (!find_matching_kcore(map, path, sizeof(path)))
2168 		return strdup(path);
2169 
2170 	/* Use current /proc/kallsyms if possible */
2171 	if (is_host) {
2172 proc_kallsyms:
2173 		return strdup("/proc/kallsyms");
2174 	}
2175 
2176 	/* Finally, find a cache of kallsyms */
2177 	if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
2178 		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
2179 		       sbuild_id);
2180 		return NULL;
2181 	}
2182 
2183 	return strdup(path);
2184 }
2185 
2186 static int dso__load_kernel_sym(struct dso *dso, struct map *map)
2187 {
2188 	int err;
2189 	const char *kallsyms_filename = NULL;
2190 	char *kallsyms_allocated_filename = NULL;
2191 	char *filename = NULL;
2192 
2193 	/*
2194 	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
2195 	 * it and only it, reporting errors to the user if it cannot be used.
2196 	 *
2197 	 * For instance, try to analyse an ARM perf.data file _without_ a
2198 	 * build-id, or if the user specifies the wrong path to the right
2199 	 * vmlinux file, obviously we can't fallback to another vmlinux (a
2200 	 * x86_86 one, on the machine where analysis is being performed, say),
2201 	 * or worse, /proc/kallsyms.
2202 	 *
2203 	 * If the specified file _has_ a build-id and there is a build-id
2204 	 * section in the perf.data file, we will still do the expected
2205 	 * validation in dso__load_vmlinux and will bail out if they don't
2206 	 * match.
2207 	 */
2208 	if (symbol_conf.kallsyms_name != NULL) {
2209 		kallsyms_filename = symbol_conf.kallsyms_name;
2210 		goto do_kallsyms;
2211 	}
2212 
2213 	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
2214 		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
2215 	}
2216 
2217 	/*
2218 	 * Before checking on common vmlinux locations, check if it's
2219 	 * stored as standard build id binary (not kallsyms) under
2220 	 * .debug cache.
2221 	 */
2222 	if (!symbol_conf.ignore_vmlinux_buildid)
2223 		filename = __dso__build_id_filename(dso, NULL, 0, false, false);
2224 	if (filename != NULL) {
2225 		err = dso__load_vmlinux(dso, map, filename, true);
2226 		if (err > 0)
2227 			return err;
2228 	}
2229 
2230 	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
2231 		err = dso__load_vmlinux_path(dso, map);
2232 		if (err > 0)
2233 			return err;
2234 	}
2235 
2236 	/* do not try local files if a symfs was given */
2237 	if (symbol_conf.symfs[0] != 0)
2238 		return -1;
2239 
2240 	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
2241 	if (!kallsyms_allocated_filename)
2242 		return -1;
2243 
2244 	kallsyms_filename = kallsyms_allocated_filename;
2245 
2246 do_kallsyms:
2247 	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2248 	if (err > 0)
2249 		pr_debug("Using %s for symbols\n", kallsyms_filename);
2250 	free(kallsyms_allocated_filename);
2251 
2252 	if (err > 0 && !dso__is_kcore(dso)) {
2253 		dso__set_binary_type(dso, DSO_BINARY_TYPE__KALLSYMS);
2254 		dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
2255 		map__fixup_start(map);
2256 		map__fixup_end(map);
2257 	}
2258 
2259 	return err;
2260 }
2261 
2262 static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
2263 {
2264 	int err;
2265 	const char *kallsyms_filename;
2266 	struct machine *machine = maps__machine(map__kmaps(map));
2267 	char path[PATH_MAX];
2268 
2269 	if (machine->kallsyms_filename) {
2270 		kallsyms_filename = machine->kallsyms_filename;
2271 	} else if (machine__is_default_guest(machine)) {
2272 		/*
2273 		 * if the user specified a vmlinux filename, use it and only
2274 		 * it, reporting errors to the user if it cannot be used.
2275 		 * Or use file guest_kallsyms inputted by user on commandline
2276 		 */
2277 		if (symbol_conf.default_guest_vmlinux_name != NULL) {
2278 			err = dso__load_vmlinux(dso, map,
2279 						symbol_conf.default_guest_vmlinux_name,
2280 						false);
2281 			return err;
2282 		}
2283 
2284 		kallsyms_filename = symbol_conf.default_guest_kallsyms;
2285 		if (!kallsyms_filename)
2286 			return -1;
2287 	} else {
2288 		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
2289 		kallsyms_filename = path;
2290 	}
2291 
2292 	err = dso__load_kallsyms(dso, kallsyms_filename, map);
2293 	if (err > 0)
2294 		pr_debug("Using %s for symbols\n", kallsyms_filename);
2295 	if (err > 0 && !dso__is_kcore(dso)) {
2296 		dso__set_binary_type(dso, DSO_BINARY_TYPE__GUEST_KALLSYMS);
2297 		dso__set_long_name(dso, machine->mmap_name, false);
2298 		map__fixup_start(map);
2299 		map__fixup_end(map);
2300 	}
2301 
2302 	return err;
2303 }
2304 
2305 static void vmlinux_path__exit(void)
2306 {
2307 	while (--vmlinux_path__nr_entries >= 0)
2308 		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
2309 	vmlinux_path__nr_entries = 0;
2310 
2311 	zfree(&vmlinux_path);
2312 }
2313 
2314 static const char * const vmlinux_paths[] = {
2315 	"vmlinux",
2316 	"/boot/vmlinux"
2317 };
2318 
2319 static const char * const vmlinux_paths_upd[] = {
2320 	"/boot/vmlinux-%s",
2321 	"/usr/lib/debug/boot/vmlinux-%s",
2322 	"/lib/modules/%s/build/vmlinux",
2323 	"/usr/lib/debug/lib/modules/%s/vmlinux",
2324 	"/usr/lib/debug/boot/vmlinux-%s.debug"
2325 };
2326 
2327 static int vmlinux_path__add(const char *new_entry)
2328 {
2329 	vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
2330 	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
2331 		return -1;
2332 	++vmlinux_path__nr_entries;
2333 
2334 	return 0;
2335 }
2336 
2337 static int vmlinux_path__init(struct perf_env *env)
2338 {
2339 	struct utsname uts;
2340 	char bf[PATH_MAX];
2341 	char *kernel_version;
2342 	unsigned int i;
2343 
2344 	vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
2345 			      ARRAY_SIZE(vmlinux_paths_upd)));
2346 	if (vmlinux_path == NULL)
2347 		return -1;
2348 
2349 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
2350 		if (vmlinux_path__add(vmlinux_paths[i]) < 0)
2351 			goto out_fail;
2352 
2353 	/* only try kernel version if no symfs was given */
2354 	if (symbol_conf.symfs[0] != 0)
2355 		return 0;
2356 
2357 	if (env) {
2358 		kernel_version = env->os_release;
2359 	} else {
2360 		if (uname(&uts) < 0)
2361 			goto out_fail;
2362 
2363 		kernel_version = uts.release;
2364 	}
2365 
2366 	for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
2367 		snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
2368 		if (vmlinux_path__add(bf) < 0)
2369 			goto out_fail;
2370 	}
2371 
2372 	return 0;
2373 
2374 out_fail:
2375 	vmlinux_path__exit();
2376 	return -1;
2377 }
2378 
2379 int setup_list(struct strlist **list, const char *list_str,
2380 		      const char *list_name)
2381 {
2382 	if (list_str == NULL)
2383 		return 0;
2384 
2385 	*list = strlist__new(list_str, NULL);
2386 	if (!*list) {
2387 		pr_err("problems parsing %s list\n", list_name);
2388 		return -1;
2389 	}
2390 
2391 	symbol_conf.has_filter = true;
2392 	return 0;
2393 }
2394 
2395 int setup_intlist(struct intlist **list, const char *list_str,
2396 		  const char *list_name)
2397 {
2398 	if (list_str == NULL)
2399 		return 0;
2400 
2401 	*list = intlist__new(list_str);
2402 	if (!*list) {
2403 		pr_err("problems parsing %s list\n", list_name);
2404 		return -1;
2405 	}
2406 	return 0;
2407 }
2408 
2409 static int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
2410 {
2411 	struct str_node *pos, *tmp;
2412 	unsigned long val;
2413 	char *sep;
2414 	const char *end;
2415 	int i = 0, err;
2416 
2417 	*addr_list = intlist__new(NULL);
2418 	if (!*addr_list)
2419 		return -1;
2420 
2421 	strlist__for_each_entry_safe(pos, tmp, sym_list) {
2422 		errno = 0;
2423 		val = strtoul(pos->s, &sep, 16);
2424 		if (errno || (sep == pos->s))
2425 			continue;
2426 
2427 		if (*sep != '\0') {
2428 			end = pos->s + strlen(pos->s) - 1;
2429 			while (end >= sep && isspace(*end))
2430 				end--;
2431 
2432 			if (end >= sep)
2433 				continue;
2434 		}
2435 
2436 		err = intlist__add(*addr_list, val);
2437 		if (err)
2438 			break;
2439 
2440 		strlist__remove(sym_list, pos);
2441 		i++;
2442 	}
2443 
2444 	if (i == 0) {
2445 		intlist__delete(*addr_list);
2446 		*addr_list = NULL;
2447 	}
2448 
2449 	return 0;
2450 }
2451 
2452 static bool symbol__read_kptr_restrict(void)
2453 {
2454 	bool value = false;
2455 	FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
2456 	bool used_root;
2457 	bool cap_syslog = perf_cap__capable(CAP_SYSLOG, &used_root);
2458 
2459 	if (fp != NULL) {
2460 		char line[8];
2461 
2462 		if (fgets(line, sizeof(line), fp) != NULL)
2463 			value = cap_syslog ? (atoi(line) >= 2) : (atoi(line) != 0);
2464 
2465 		fclose(fp);
2466 	}
2467 
2468 	/* Per kernel/kallsyms.c:
2469 	 * we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
2470 	 */
2471 	if (perf_event_paranoid() > 1 && !cap_syslog)
2472 		value = true;
2473 
2474 	return value;
2475 }
2476 
2477 int symbol__annotation_init(void)
2478 {
2479 	if (symbol_conf.init_annotation)
2480 		return 0;
2481 
2482 	if (symbol_conf.initialized) {
2483 		pr_err("Annotation needs to be init before symbol__init()\n");
2484 		return -1;
2485 	}
2486 
2487 	symbol_conf.priv_size += sizeof(struct annotation);
2488 	symbol_conf.init_annotation = true;
2489 	return 0;
2490 }
2491 
2492 static int setup_parallelism_bitmap(void)
2493 {
2494 	struct perf_cpu_map *map;
2495 	struct perf_cpu cpu;
2496 	int i, err = -1;
2497 
2498 	if (symbol_conf.parallelism_list_str == NULL)
2499 		return 0;
2500 
2501 	map = perf_cpu_map__new(symbol_conf.parallelism_list_str);
2502 	if (map == NULL) {
2503 		pr_err("failed to parse parallelism filter list\n");
2504 		return -1;
2505 	}
2506 
2507 	bitmap_fill(symbol_conf.parallelism_filter, MAX_NR_CPUS + 1);
2508 	perf_cpu_map__for_each_cpu(cpu, i, map) {
2509 		if (cpu.cpu <= 0 || cpu.cpu > MAX_NR_CPUS) {
2510 			pr_err("Requested parallelism level %d is invalid.\n", cpu.cpu);
2511 			goto out_delete_map;
2512 		}
2513 		__clear_bit(cpu.cpu, symbol_conf.parallelism_filter);
2514 	}
2515 
2516 	err = 0;
2517 out_delete_map:
2518 	perf_cpu_map__put(map);
2519 	return err;
2520 }
2521 
2522 int symbol__init(struct perf_env *env)
2523 {
2524 	const char *symfs;
2525 
2526 	if (symbol_conf.initialized)
2527 		return 0;
2528 
2529 	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
2530 
2531 	symbol__elf_init();
2532 
2533 	if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
2534 		return -1;
2535 
2536 	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
2537 		pr_err("'.' is the only non valid --field-separator argument\n");
2538 		return -1;
2539 	}
2540 
2541 	if (setup_parallelism_bitmap())
2542 		return -1;
2543 
2544 	if (setup_list(&symbol_conf.dso_list,
2545 		       symbol_conf.dso_list_str, "dso") < 0)
2546 		return -1;
2547 
2548 	if (setup_list(&symbol_conf.comm_list,
2549 		       symbol_conf.comm_list_str, "comm") < 0)
2550 		goto out_free_dso_list;
2551 
2552 	if (setup_intlist(&symbol_conf.pid_list,
2553 		       symbol_conf.pid_list_str, "pid") < 0)
2554 		goto out_free_comm_list;
2555 
2556 	if (setup_intlist(&symbol_conf.tid_list,
2557 		       symbol_conf.tid_list_str, "tid") < 0)
2558 		goto out_free_pid_list;
2559 
2560 	if (setup_list(&symbol_conf.sym_list,
2561 		       symbol_conf.sym_list_str, "symbol") < 0)
2562 		goto out_free_tid_list;
2563 
2564 	if (symbol_conf.sym_list &&
2565 	    setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
2566 		goto out_free_sym_list;
2567 
2568 	if (setup_list(&symbol_conf.bt_stop_list,
2569 		       symbol_conf.bt_stop_list_str, "symbol") < 0)
2570 		goto out_free_sym_list;
2571 
2572 	/*
2573 	 * A path to symbols of "/" is identical to ""
2574 	 * reset here for simplicity.
2575 	 */
2576 	symfs = realpath(symbol_conf.symfs, NULL);
2577 	if (symfs == NULL)
2578 		symfs = symbol_conf.symfs;
2579 	if (strcmp(symfs, "/") == 0)
2580 		symbol_conf.symfs = "";
2581 	if (symfs != symbol_conf.symfs)
2582 		free((void *)symfs);
2583 
2584 	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
2585 
2586 	symbol_conf.initialized = true;
2587 	return 0;
2588 
2589 out_free_sym_list:
2590 	strlist__delete(symbol_conf.sym_list);
2591 	intlist__delete(symbol_conf.addr_list);
2592 out_free_tid_list:
2593 	intlist__delete(symbol_conf.tid_list);
2594 out_free_pid_list:
2595 	intlist__delete(symbol_conf.pid_list);
2596 out_free_comm_list:
2597 	strlist__delete(symbol_conf.comm_list);
2598 out_free_dso_list:
2599 	strlist__delete(symbol_conf.dso_list);
2600 	return -1;
2601 }
2602 
2603 void symbol__exit(void)
2604 {
2605 	if (!symbol_conf.initialized)
2606 		return;
2607 	strlist__delete(symbol_conf.bt_stop_list);
2608 	strlist__delete(symbol_conf.sym_list);
2609 	strlist__delete(symbol_conf.dso_list);
2610 	strlist__delete(symbol_conf.comm_list);
2611 	intlist__delete(symbol_conf.tid_list);
2612 	intlist__delete(symbol_conf.pid_list);
2613 	intlist__delete(symbol_conf.addr_list);
2614 	vmlinux_path__exit();
2615 	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
2616 	symbol_conf.bt_stop_list = NULL;
2617 	symbol_conf.initialized = false;
2618 }
2619 
2620 int symbol__config_symfs(const struct option *opt __maybe_unused,
2621 			 const char *dir, int unset __maybe_unused)
2622 {
2623 	char *bf = NULL;
2624 	int ret;
2625 
2626 	symbol_conf.symfs = strdup(dir);
2627 	if (symbol_conf.symfs == NULL)
2628 		return -ENOMEM;
2629 
2630 	/* skip the locally configured cache if a symfs is given, and
2631 	 * config buildid dir to symfs/.debug
2632 	 */
2633 	ret = asprintf(&bf, "%s/%s", dir, ".debug");
2634 	if (ret < 0)
2635 		return -ENOMEM;
2636 
2637 	set_buildid_dir(bf);
2638 
2639 	free(bf);
2640 	return 0;
2641 }
2642 
2643 /*
2644  * Checks that user supplied symbol kernel files are accessible because
2645  * the default mechanism for accessing elf files fails silently. i.e. if
2646  * debug syms for a build ID aren't found perf carries on normally. When
2647  * they are user supplied we should assume that the user doesn't want to
2648  * silently fail.
2649  */
2650 int symbol__validate_sym_arguments(void)
2651 {
2652 	if (symbol_conf.vmlinux_name &&
2653 	    access(symbol_conf.vmlinux_name, R_OK)) {
2654 		pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
2655 		return -EINVAL;
2656 	}
2657 	if (symbol_conf.kallsyms_name &&
2658 	    access(symbol_conf.kallsyms_name, R_OK)) {
2659 		pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
2660 		return -EINVAL;
2661 	}
2662 	return 0;
2663 }
2664 
2665 static bool want_demangle(bool is_kernel_sym)
2666 {
2667 	return is_kernel_sym ? symbol_conf.demangle_kernel : symbol_conf.demangle;
2668 }
2669 
2670 /*
2671  * Demangle C++ function signature, typically replaced by demangle-cxx.cpp
2672  * version.
2673  */
2674 #ifndef HAVE_CXA_DEMANGLE_SUPPORT
2675 char *cxx_demangle_sym(const char *str __maybe_unused, bool params __maybe_unused,
2676 		       bool modifiers __maybe_unused)
2677 {
2678 #ifdef HAVE_LIBBFD_SUPPORT
2679 	int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0);
2680 
2681 	return bfd_demangle(NULL, str, flags);
2682 #elif defined(HAVE_CPLUS_DEMANGLE_SUPPORT)
2683 	int flags = (params ? DMGL_PARAMS : 0) | (modifiers ? DMGL_ANSI : 0);
2684 
2685 	return cplus_demangle(str, flags);
2686 #else
2687 	return NULL;
2688 #endif
2689 }
2690 #endif /* !HAVE_CXA_DEMANGLE_SUPPORT */
2691 
2692 char *dso__demangle_sym(struct dso *dso, int kmodule, const char *elf_name)
2693 {
2694 	struct demangle rust_demangle = {
2695 		.style = DemangleStyleUnknown,
2696 	};
2697 	char *demangled = NULL;
2698 
2699 	/*
2700 	 * We need to figure out if the object was created from C++ sources
2701 	 * DWARF DW_compile_unit has this, but we don't always have access
2702 	 * to it...
2703 	 */
2704 	if (!want_demangle((dso && dso__kernel(dso)) || kmodule))
2705 		return demangled;
2706 
2707 	rust_demangle_demangle(elf_name, &rust_demangle);
2708 	if (rust_demangle_is_known(&rust_demangle)) {
2709 		/* A rust mangled name. */
2710 		if (rust_demangle.mangled_len == 0)
2711 			return demangled;
2712 
2713 		for (size_t buf_len = roundup_pow_of_two(rust_demangle.mangled_len * 2);
2714 		     buf_len < 1024 * 1024; buf_len += 32) {
2715 			char *tmp = realloc(demangled, buf_len);
2716 
2717 			if (!tmp) {
2718 				/* Failure to grow output buffer, return what is there. */
2719 				return demangled;
2720 			}
2721 			demangled = tmp;
2722 			if (rust_demangle_display_demangle(&rust_demangle, demangled, buf_len,
2723 							   /*alternate=*/true) == OverflowOk)
2724 				return demangled;
2725 		}
2726 		/* Buffer exceeded sensible bounds, return what is there. */
2727 		return demangled;
2728 	}
2729 
2730 	demangled = cxx_demangle_sym(elf_name, verbose > 0, verbose > 0);
2731 	if (demangled)
2732 		return demangled;
2733 
2734 	demangled = ocaml_demangle_sym(elf_name);
2735 	if (demangled)
2736 		return demangled;
2737 
2738 	return java_demangle_sym(elf_name, JAVA_DEMANGLE_NORET);
2739 }
2740