symbol.c 40.6 KB
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#include <dirent.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <fcntl.h>
#include <unistd.h>
11
#include <inttypes.h>
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#include "build-id.h"
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#include "util.h"
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#include "debug.h"
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#include "machine.h"
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#include "symbol.h"
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#include "strlist.h"
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#include <elf.h>
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#include <limits.h>
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#include <symbol/kallsyms.h>
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#include <sys/utsname.h>
P
Peter Zijlstra 已提交
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static int dso__load_kernel_sym(struct dso *dso, struct map *map,
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				symbol_filter_t filter);
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static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
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			symbol_filter_t filter);
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int vmlinux_path__nr_entries;
char **vmlinux_path;
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struct symbol_conf symbol_conf = {
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	.use_modules	  = true,
	.try_vmlinux_path = true,
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	.annotate_src	  = true,
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	.demangle	  = true,
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	.symfs            = "",
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};

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static enum dso_binary_type binary_type_symtab[] = {
	DSO_BINARY_TYPE__KALLSYMS,
	DSO_BINARY_TYPE__GUEST_KALLSYMS,
	DSO_BINARY_TYPE__JAVA_JIT,
	DSO_BINARY_TYPE__DEBUGLINK,
	DSO_BINARY_TYPE__BUILD_ID_CACHE,
	DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
	DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
	DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
	DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
	DSO_BINARY_TYPE__GUEST_KMODULE,
	DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
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	DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
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	DSO_BINARY_TYPE__NOT_FOUND,
};

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#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
56

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bool symbol_type__is_a(char symbol_type, enum map_type map_type)
58
{
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	symbol_type = toupper(symbol_type);

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	switch (map_type) {
	case MAP__FUNCTION:
		return symbol_type == 'T' || symbol_type == 'W';
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	case MAP__VARIABLE:
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		return symbol_type == 'D';
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	default:
		return false;
	}
}

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static int prefix_underscores_count(const char *str)
{
	const char *tail = str;

	while (*tail == '_')
		tail++;

	return tail - str;
}

#define SYMBOL_A 0
#define SYMBOL_B 1

static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
{
	s64 a;
	s64 b;
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	size_t na, nb;
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	/* Prefer a symbol with non zero length */
	a = syma->end - syma->start;
	b = symb->end - symb->start;
	if ((b == 0) && (a > 0))
		return SYMBOL_A;
	else if ((a == 0) && (b > 0))
		return SYMBOL_B;

	/* Prefer a non weak symbol over a weak one */
	a = syma->binding == STB_WEAK;
	b = symb->binding == STB_WEAK;
	if (b && !a)
		return SYMBOL_A;
	if (a && !b)
		return SYMBOL_B;

	/* Prefer a global symbol over a non global one */
	a = syma->binding == STB_GLOBAL;
	b = symb->binding == STB_GLOBAL;
	if (a && !b)
		return SYMBOL_A;
	if (b && !a)
		return SYMBOL_B;

	/* Prefer a symbol with less underscores */
	a = prefix_underscores_count(syma->name);
	b = prefix_underscores_count(symb->name);
	if (b > a)
		return SYMBOL_A;
	else if (a > b)
		return SYMBOL_B;

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	/* Choose the symbol with the longest name */
	na = strlen(syma->name);
	nb = strlen(symb->name);
	if (na > nb)
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		return SYMBOL_A;
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	else if (na < nb)
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		return SYMBOL_B;
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	/* Avoid "SyS" kernel syscall aliases */
	if (na >= 3 && !strncmp(syma->name, "SyS", 3))
		return SYMBOL_B;
	if (na >= 10 && !strncmp(syma->name, "compat_SyS", 10))
		return SYMBOL_B;

	return SYMBOL_A;
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}

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void symbols__fixup_duplicate(struct rb_root *symbols)
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{
	struct rb_node *nd;
	struct symbol *curr, *next;

	nd = rb_first(symbols);

	while (nd) {
		curr = rb_entry(nd, struct symbol, rb_node);
again:
		nd = rb_next(&curr->rb_node);
		next = rb_entry(nd, struct symbol, rb_node);

		if (!nd)
			break;

		if (curr->start != next->start)
			continue;

		if (choose_best_symbol(curr, next) == SYMBOL_A) {
			rb_erase(&next->rb_node, symbols);
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			symbol__delete(next);
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			goto again;
		} else {
			nd = rb_next(&curr->rb_node);
			rb_erase(&curr->rb_node, symbols);
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			symbol__delete(curr);
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		}
	}
}

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void symbols__fixup_end(struct rb_root *symbols)
171
{
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	struct rb_node *nd, *prevnd = rb_first(symbols);
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	struct symbol *curr, *prev;
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	if (prevnd == NULL)
		return;

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	curr = rb_entry(prevnd, struct symbol, rb_node);

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	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
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		prev = curr;
		curr = rb_entry(nd, struct symbol, rb_node);
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		if (prev->end == prev->start && prev->end != curr->start)
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			prev->end = curr->start - 1;
	}
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	/* Last entry */
	if (curr->end == curr->start)
		curr->end = roundup(curr->start, 4096);
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}

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void __map_groups__fixup_end(struct map_groups *mg, enum map_type type)
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{
	struct map *prev, *curr;
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	struct rb_node *nd, *prevnd = rb_first(&mg->maps[type]);
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	if (prevnd == NULL)
		return;

	curr = rb_entry(prevnd, struct map, rb_node);

	for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
		prev = curr;
		curr = rb_entry(nd, struct map, rb_node);
		prev->end = curr->start - 1;
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	}
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	/*
	 * We still haven't the actual symbols, so guess the
	 * last map final address.
	 */
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	curr->end = ~0ULL;
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}

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struct symbol *symbol__new(u64 start, u64 len, u8 binding, const char *name)
217
{
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	size_t namelen = strlen(name) + 1;
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	struct symbol *sym = calloc(1, (symbol_conf.priv_size +
					sizeof(*sym) + namelen));
	if (sym == NULL)
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		return NULL;

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	if (symbol_conf.priv_size)
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		sym = ((void *)sym) + symbol_conf.priv_size;
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	sym->start   = start;
	sym->end     = len ? start + len - 1 : start;
	sym->binding = binding;
	sym->namelen = namelen - 1;
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	pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
		  __func__, name, start, sym->end);
	memcpy(sym->name, name, namelen);
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	return sym;
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}

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void symbol__delete(struct symbol *sym)
240
{
241
	free(((void *)sym) - symbol_conf.priv_size);
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}

244
size_t symbol__fprintf(struct symbol *sym, FILE *fp)
245
{
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	return fprintf(fp, " %" PRIx64 "-%" PRIx64 " %c %s\n",
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		       sym->start, sym->end,
		       sym->binding == STB_GLOBAL ? 'g' :
		       sym->binding == STB_LOCAL  ? 'l' : 'w',
		       sym->name);
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}

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size_t symbol__fprintf_symname_offs(const struct symbol *sym,
				    const struct addr_location *al, FILE *fp)
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{
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	unsigned long offset;
	size_t length;

	if (sym && sym->name) {
		length = fprintf(fp, "%s", sym->name);
		if (al) {
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			if (al->addr < sym->end)
				offset = al->addr - sym->start;
			else
				offset = al->addr - al->map->start - sym->start;
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			length += fprintf(fp, "+0x%lx", offset);
		}
		return length;
	} else
		return fprintf(fp, "[unknown]");
}
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size_t symbol__fprintf_symname(const struct symbol *sym, FILE *fp)
{
	return symbol__fprintf_symname_offs(sym, NULL, fp);
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}

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void symbols__delete(struct rb_root *symbols)
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{
	struct symbol *pos;
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	struct rb_node *next = rb_first(symbols);
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	while (next) {
		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);
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		rb_erase(&pos->rb_node, symbols);
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		symbol__delete(pos);
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	}
}

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void symbols__insert(struct rb_root *symbols, struct symbol *sym)
292
{
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	struct rb_node **p = &symbols->rb_node;
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	struct rb_node *parent = NULL;
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	const u64 ip = sym->start;
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	struct symbol *s;

	while (*p != NULL) {
		parent = *p;
		s = rb_entry(parent, struct symbol, rb_node);
		if (ip < s->start)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&sym->rb_node, parent, p);
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	rb_insert_color(&sym->rb_node, symbols);
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}

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static struct symbol *symbols__find(struct rb_root *symbols, u64 ip)
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{
	struct rb_node *n;

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	if (symbols == NULL)
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		return NULL;

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	n = symbols->rb_node;
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	while (n) {
		struct symbol *s = rb_entry(n, struct symbol, rb_node);

		if (ip < s->start)
			n = n->rb_left;
		else if (ip > s->end)
			n = n->rb_right;
		else
			return s;
	}

	return NULL;
}

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static struct symbol *symbols__first(struct rb_root *symbols)
{
	struct rb_node *n = rb_first(symbols);

	if (n)
		return rb_entry(n, struct symbol, rb_node);

	return NULL;
}

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struct symbol_name_rb_node {
	struct rb_node	rb_node;
	struct symbol	sym;
};

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static void symbols__insert_by_name(struct rb_root *symbols, struct symbol *sym)
349
{
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	struct rb_node **p = &symbols->rb_node;
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	struct rb_node *parent = NULL;
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	struct symbol_name_rb_node *symn, *s;

	symn = container_of(sym, struct symbol_name_rb_node, sym);
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	while (*p != NULL) {
		parent = *p;
		s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
		if (strcmp(sym->name, s->sym.name) < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&symn->rb_node, parent, p);
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	rb_insert_color(&symn->rb_node, symbols);
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}

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static void symbols__sort_by_name(struct rb_root *symbols,
				  struct rb_root *source)
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{
	struct rb_node *nd;

	for (nd = rb_first(source); nd; nd = rb_next(nd)) {
		struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
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		symbols__insert_by_name(symbols, pos);
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	}
}

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static struct symbol *symbols__find_by_name(struct rb_root *symbols,
					    const char *name)
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{
	struct rb_node *n;

384
	if (symbols == NULL)
385 386
		return NULL;

387
	n = symbols->rb_node;
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	while (n) {
		struct symbol_name_rb_node *s;
		int cmp;

		s = rb_entry(n, struct symbol_name_rb_node, rb_node);
		cmp = strcmp(name, s->sym.name);

		if (cmp < 0)
			n = n->rb_left;
		else if (cmp > 0)
			n = n->rb_right;
		else
			return &s->sym;
	}

	return NULL;
}

407
struct symbol *dso__find_symbol(struct dso *dso,
408
				enum map_type type, u64 addr)
409
{
410
	return symbols__find(&dso->symbols[type], addr);
411 412
}

413
static struct symbol *dso__first_symbol(struct dso *dso, enum map_type type)
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{
	return symbols__first(&dso->symbols[type]);
}

418
struct symbol *dso__find_symbol_by_name(struct dso *dso, enum map_type type,
419 420
					const char *name)
{
421
	return symbols__find_by_name(&dso->symbol_names[type], name);
422 423
}

424
void dso__sort_by_name(struct dso *dso, enum map_type type)
425
{
426 427 428
	dso__set_sorted_by_name(dso, type);
	return symbols__sort_by_name(&dso->symbol_names[type],
				     &dso->symbols[type]);
429 430
}

431 432
size_t dso__fprintf_symbols_by_name(struct dso *dso,
				    enum map_type type, FILE *fp)
433 434 435 436 437
{
	size_t ret = 0;
	struct rb_node *nd;
	struct symbol_name_rb_node *pos;

438
	for (nd = rb_first(&dso->symbol_names[type]); nd; nd = rb_next(nd)) {
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		pos = rb_entry(nd, struct symbol_name_rb_node, rb_node);
		fprintf(fp, "%s\n", pos->sym.name);
	}

	return ret;
}

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int modules__parse(const char *filename, void *arg,
		   int (*process_module)(void *arg, const char *name,
					 u64 start))
{
	char *line = NULL;
	size_t n;
	FILE *file;
	int err = 0;

	file = fopen(filename, "r");
	if (file == NULL)
		return -1;

	while (1) {
		char name[PATH_MAX];
		u64 start;
		char *sep;
		ssize_t line_len;

		line_len = getline(&line, &n, file);
		if (line_len < 0) {
			if (feof(file))
				break;
			err = -1;
			goto out;
		}

		if (!line) {
			err = -1;
			goto out;
		}

		line[--line_len] = '\0'; /* \n */

		sep = strrchr(line, 'x');
		if (sep == NULL)
			continue;

		hex2u64(sep + 1, &start);

		sep = strchr(line, ' ');
		if (sep == NULL)
			continue;

		*sep = '\0';

		scnprintf(name, sizeof(name), "[%s]", line);

		err = process_module(arg, name, start);
		if (err)
			break;
	}
out:
	free(line);
	fclose(file);
	return err;
}

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struct process_kallsyms_args {
	struct map *map;
	struct dso *dso;
};

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bool symbol__is_idle(struct symbol *sym)
{
	const char * const idle_symbols[] = {
		"cpu_idle",
		"intel_idle",
		"default_idle",
		"native_safe_halt",
		"enter_idle",
		"exit_idle",
		"mwait_idle",
		"mwait_idle_with_hints",
		"poll_idle",
		"ppc64_runlatch_off",
		"pseries_dedicated_idle_sleep",
		NULL
	};

	int i;

	if (!sym)
		return false;

	for (i = 0; idle_symbols[i]; i++) {
		if (!strcmp(idle_symbols[i], sym->name))
			return true;
	}

	return false;
}

539
static int map__process_kallsym_symbol(void *arg, const char *name,
540
				       char type, u64 start)
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{
	struct symbol *sym;
	struct process_kallsyms_args *a = arg;
	struct rb_root *root = &a->dso->symbols[a->map->type];

	if (!symbol_type__is_a(type, a->map->type))
		return 0;

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	/*
	 * module symbols are not sorted so we add all
	 * symbols, setting length to 0, and rely on
	 * symbols__fixup_end() to fix it up.
	 */
	sym = symbol__new(start, 0, kallsyms2elf_type(type), name);
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	if (sym == NULL)
		return -ENOMEM;
	/*
	 * We will pass the symbols to the filter later, in
	 * map__split_kallsyms, when we have split the maps per module
	 */
	symbols__insert(root, sym);
562

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	return 0;
}

/*
 * Loads the function entries in /proc/kallsyms into kernel_map->dso,
 * so that we can in the next step set the symbol ->end address and then
 * call kernel_maps__split_kallsyms.
 */
571
static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
572
				  struct map *map)
573
{
574
	struct process_kallsyms_args args = { .map = map, .dso = dso, };
575
	return kallsyms__parse(filename, &args, map__process_kallsym_symbol);
576 577
}

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static int dso__split_kallsyms_for_kcore(struct dso *dso, struct map *map,
					 symbol_filter_t filter)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	struct map *curr_map;
	struct symbol *pos;
	int count = 0, moved = 0;
	struct rb_root *root = &dso->symbols[map->type];
	struct rb_node *next = rb_first(root);

	while (next) {
		char *module;

		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);

		module = strchr(pos->name, '\t');
		if (module)
			*module = '\0';

		curr_map = map_groups__find(kmaps, map->type, pos->start);

		if (!curr_map || (filter && filter(curr_map, pos))) {
			rb_erase(&pos->rb_node, root);
			symbol__delete(pos);
		} else {
			pos->start -= curr_map->start - curr_map->pgoff;
			if (pos->end)
				pos->end -= curr_map->start - curr_map->pgoff;
			if (curr_map != map) {
				rb_erase(&pos->rb_node, root);
				symbols__insert(
					&curr_map->dso->symbols[curr_map->type],
					pos);
				++moved;
			} else {
				++count;
			}
		}
	}

	/* Symbols have been adjusted */
	dso->adjust_symbols = 1;

	return count + moved;
}

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/*
 * Split the symbols into maps, making sure there are no overlaps, i.e. the
 * kernel range is broken in several maps, named [kernel].N, as we don't have
 * the original ELF section names vmlinux have.
 */
630
static int dso__split_kallsyms(struct dso *dso, struct map *map, u64 delta,
631
			       symbol_filter_t filter)
632
{
633
	struct map_groups *kmaps = map__kmap(map)->kmaps;
634
	struct machine *machine = kmaps->machine;
635
	struct map *curr_map = map;
636
	struct symbol *pos;
637
	int count = 0, moved = 0;	
638
	struct rb_root *root = &dso->symbols[map->type];
639
	struct rb_node *next = rb_first(root);
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	int kernel_range = 0;

	while (next) {
		char *module;

		pos = rb_entry(next, struct symbol, rb_node);
		next = rb_next(&pos->rb_node);

		module = strchr(pos->name, '\t');
		if (module) {
650
			if (!symbol_conf.use_modules)
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				goto discard_symbol;

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			*module++ = '\0';

655
			if (strcmp(curr_map->dso->short_name, module)) {
656
				if (curr_map != map &&
657
				    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
658
				    machine__is_default_guest(machine)) {
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					/*
					 * We assume all symbols of a module are
					 * continuous in * kallsyms, so curr_map
					 * points to a module and all its
					 * symbols are in its kmap. Mark it as
					 * loaded.
					 */
					dso__set_loaded(curr_map->dso,
							curr_map->type);
				}

				curr_map = map_groups__find_by_name(kmaps,
							map->type, module);
672
				if (curr_map == NULL) {
673
					pr_debug("%s/proc/{kallsyms,modules} "
674
					         "inconsistency while looking "
675
						 "for \"%s\" module!\n",
676
						 machine->root_dir, module);
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					curr_map = map;
					goto discard_symbol;
679
				}
680

681
				if (curr_map->dso->loaded &&
682
				    !machine__is_default_guest(machine))
683
					goto discard_symbol;
684
			}
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			/*
			 * So that we look just like we get from .ko files,
			 * i.e. not prelinked, relative to map->start.
			 */
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			pos->start = curr_map->map_ip(curr_map, pos->start);
			pos->end   = curr_map->map_ip(curr_map, pos->end);
		} else if (curr_map != map) {
692
			char dso_name[PATH_MAX];
693
			struct dso *ndso;
694

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			if (delta) {
				/* Kernel was relocated at boot time */
				pos->start -= delta;
				pos->end -= delta;
			}

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			if (count == 0) {
				curr_map = map;
				goto filter_symbol;
			}

706
			if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
707 708 709 710 711 712 713
				snprintf(dso_name, sizeof(dso_name),
					"[guest.kernel].%d",
					kernel_range++);
			else
				snprintf(dso_name, sizeof(dso_name),
					"[kernel].%d",
					kernel_range++);
714

715 716
			ndso = dso__new(dso_name);
			if (ndso == NULL)
717 718
				return -1;

719
			ndso->kernel = dso->kernel;
720

721
			curr_map = map__new2(pos->start, ndso, map->type);
722
			if (curr_map == NULL) {
723
				dso__delete(ndso);
724 725
				return -1;
			}
726

727
			curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
728
			map_groups__insert(kmaps, curr_map);
729
			++kernel_range;
730 731 732 733
		} else if (delta) {
			/* Kernel was relocated at boot time */
			pos->start -= delta;
			pos->end -= delta;
734
		}
735
filter_symbol:
736
		if (filter && filter(curr_map, pos)) {
737
discard_symbol:		rb_erase(&pos->rb_node, root);
738
			symbol__delete(pos);
739
		} else {
740 741 742
			if (curr_map != map) {
				rb_erase(&pos->rb_node, root);
				symbols__insert(&curr_map->dso->symbols[curr_map->type], pos);
743 744 745
				++moved;
			} else
				++count;
746
		}
747 748
	}

749
	if (curr_map != map &&
750
	    dso->kernel == DSO_TYPE_GUEST_KERNEL &&
751
	    machine__is_default_guest(kmaps->machine)) {
752 753 754
		dso__set_loaded(curr_map->dso, curr_map->type);
	}

755
	return count + moved;
756
}
757

758 759
bool symbol__restricted_filename(const char *filename,
				 const char *restricted_filename)
760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775
{
	bool restricted = false;

	if (symbol_conf.kptr_restrict) {
		char *r = realpath(filename, NULL);

		if (r != NULL) {
			restricted = strcmp(r, restricted_filename) == 0;
			free(r);
			return restricted;
		}
	}

	return restricted;
}

776 777 778 779
struct module_info {
	struct rb_node rb_node;
	char *name;
	u64 start;
780 781
};

782
static void add_module(struct module_info *mi, struct rb_root *modules)
783
{
784 785 786
	struct rb_node **p = &modules->rb_node;
	struct rb_node *parent = NULL;
	struct module_info *m;
787

788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808
	while (*p != NULL) {
		parent = *p;
		m = rb_entry(parent, struct module_info, rb_node);
		if (strcmp(mi->name, m->name) < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}
	rb_link_node(&mi->rb_node, parent, p);
	rb_insert_color(&mi->rb_node, modules);
}

static void delete_modules(struct rb_root *modules)
{
	struct module_info *mi;
	struct rb_node *next = rb_first(modules);

	while (next) {
		mi = rb_entry(next, struct module_info, rb_node);
		next = rb_next(&mi->rb_node);
		rb_erase(&mi->rb_node, modules);
809
		zfree(&mi->name);
810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842
		free(mi);
	}
}

static struct module_info *find_module(const char *name,
				       struct rb_root *modules)
{
	struct rb_node *n = modules->rb_node;

	while (n) {
		struct module_info *m;
		int cmp;

		m = rb_entry(n, struct module_info, rb_node);
		cmp = strcmp(name, m->name);
		if (cmp < 0)
			n = n->rb_left;
		else if (cmp > 0)
			n = n->rb_right;
		else
			return m;
	}

	return NULL;
}

static int __read_proc_modules(void *arg, const char *name, u64 start)
{
	struct rb_root *modules = arg;
	struct module_info *mi;

	mi = zalloc(sizeof(struct module_info));
	if (!mi)
843 844
		return -ENOMEM;

845 846
	mi->name = strdup(name);
	mi->start = start;
847

848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866
	if (!mi->name) {
		free(mi);
		return -ENOMEM;
	}

	add_module(mi, modules);

	return 0;
}

static int read_proc_modules(const char *filename, struct rb_root *modules)
{
	if (symbol__restricted_filename(filename, "/proc/modules"))
		return -1;

	if (modules__parse(filename, modules, __read_proc_modules)) {
		delete_modules(modules);
		return -1;
	}
867 868 869 870

	return 0;
}

871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911
int compare_proc_modules(const char *from, const char *to)
{
	struct rb_root from_modules = RB_ROOT;
	struct rb_root to_modules = RB_ROOT;
	struct rb_node *from_node, *to_node;
	struct module_info *from_m, *to_m;
	int ret = -1;

	if (read_proc_modules(from, &from_modules))
		return -1;

	if (read_proc_modules(to, &to_modules))
		goto out_delete_from;

	from_node = rb_first(&from_modules);
	to_node = rb_first(&to_modules);
	while (from_node) {
		if (!to_node)
			break;

		from_m = rb_entry(from_node, struct module_info, rb_node);
		to_m = rb_entry(to_node, struct module_info, rb_node);

		if (from_m->start != to_m->start ||
		    strcmp(from_m->name, to_m->name))
			break;

		from_node = rb_next(from_node);
		to_node = rb_next(to_node);
	}

	if (!from_node && !to_node)
		ret = 0;

	delete_modules(&to_modules);
out_delete_from:
	delete_modules(&from_modules);

	return ret;
}

912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947
static int do_validate_kcore_modules(const char *filename, struct map *map,
				  struct map_groups *kmaps)
{
	struct rb_root modules = RB_ROOT;
	struct map *old_map;
	int err;

	err = read_proc_modules(filename, &modules);
	if (err)
		return err;

	old_map = map_groups__first(kmaps, map->type);
	while (old_map) {
		struct map *next = map_groups__next(old_map);
		struct module_info *mi;

		if (old_map == map || old_map->start == map->start) {
			/* The kernel map */
			old_map = next;
			continue;
		}

		/* Module must be in memory at the same address */
		mi = find_module(old_map->dso->short_name, &modules);
		if (!mi || mi->start != old_map->start) {
			err = -EINVAL;
			goto out;
		}

		old_map = next;
	}
out:
	delete_modules(&modules);
	return err;
}

948
/*
949
 * If kallsyms is referenced by name then we look for filename in the same
950 951
 * directory.
 */
952 953 954
static bool filename_from_kallsyms_filename(char *filename,
					    const char *base_name,
					    const char *kallsyms_filename)
955 956 957
{
	char *name;

958 959
	strcpy(filename, kallsyms_filename);
	name = strrchr(filename, '/');
960 961 962
	if (!name)
		return false;

963 964 965 966
	name += 1;

	if (!strcmp(name, "kallsyms")) {
		strcpy(name, base_name);
967 968 969 970 971 972
		return true;
	}

	return false;
}

973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988
static int validate_kcore_modules(const char *kallsyms_filename,
				  struct map *map)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	char modules_filename[PATH_MAX];

	if (!filename_from_kallsyms_filename(modules_filename, "modules",
					     kallsyms_filename))
		return -EINVAL;

	if (do_validate_kcore_modules(modules_filename, map, kmaps))
		return -EINVAL;

	return 0;
}

989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005
static int validate_kcore_addresses(const char *kallsyms_filename,
				    struct map *map)
{
	struct kmap *kmap = map__kmap(map);

	if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
		u64 start;

		start = kallsyms__get_function_start(kallsyms_filename,
						     kmap->ref_reloc_sym->name);
		if (start != kmap->ref_reloc_sym->addr)
			return -EINVAL;
	}

	return validate_kcore_modules(kallsyms_filename, map);
}

1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028
struct kcore_mapfn_data {
	struct dso *dso;
	enum map_type type;
	struct list_head maps;
};

static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
{
	struct kcore_mapfn_data *md = data;
	struct map *map;

	map = map__new2(start, md->dso, md->type);
	if (map == NULL)
		return -ENOMEM;

	map->end = map->start + len;
	map->pgoff = pgoff;

	list_add(&map->node, &md->maps);

	return 0;
}

1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044
static int dso__load_kcore(struct dso *dso, struct map *map,
			   const char *kallsyms_filename)
{
	struct map_groups *kmaps = map__kmap(map)->kmaps;
	struct machine *machine = kmaps->machine;
	struct kcore_mapfn_data md;
	struct map *old_map, *new_map, *replacement_map = NULL;
	bool is_64_bit;
	int err, fd;
	char kcore_filename[PATH_MAX];
	struct symbol *sym;

	/* This function requires that the map is the kernel map */
	if (map != machine->vmlinux_maps[map->type])
		return -EINVAL;

1045 1046 1047 1048
	if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
					     kallsyms_filename))
		return -EINVAL;

1049 1050
	/* Modules and kernel must be present at their original addresses */
	if (validate_kcore_addresses(kallsyms_filename, map))
1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118
		return -EINVAL;

	md.dso = dso;
	md.type = map->type;
	INIT_LIST_HEAD(&md.maps);

	fd = open(kcore_filename, O_RDONLY);
	if (fd < 0)
		return -EINVAL;

	/* Read new maps into temporary lists */
	err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
			      &is_64_bit);
	if (err)
		goto out_err;

	if (list_empty(&md.maps)) {
		err = -EINVAL;
		goto out_err;
	}

	/* Remove old maps */
	old_map = map_groups__first(kmaps, map->type);
	while (old_map) {
		struct map *next = map_groups__next(old_map);

		if (old_map != map)
			map_groups__remove(kmaps, old_map);
		old_map = next;
	}

	/* Find the kernel map using the first symbol */
	sym = dso__first_symbol(dso, map->type);
	list_for_each_entry(new_map, &md.maps, node) {
		if (sym && sym->start >= new_map->start &&
		    sym->start < new_map->end) {
			replacement_map = new_map;
			break;
		}
	}

	if (!replacement_map)
		replacement_map = list_entry(md.maps.next, struct map, node);

	/* Add new maps */
	while (!list_empty(&md.maps)) {
		new_map = list_entry(md.maps.next, struct map, node);
		list_del(&new_map->node);
		if (new_map == replacement_map) {
			map->start	= new_map->start;
			map->end	= new_map->end;
			map->pgoff	= new_map->pgoff;
			map->map_ip	= new_map->map_ip;
			map->unmap_ip	= new_map->unmap_ip;
			map__delete(new_map);
			/* Ensure maps are correctly ordered */
			map_groups__remove(kmaps, map);
			map_groups__insert(kmaps, map);
		} else {
			map_groups__insert(kmaps, new_map);
		}
	}

	/*
	 * Set the data type and long name so that kcore can be read via
	 * dso__data_read_addr().
	 */
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1119
		dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
1120
	else
1121
		dso->binary_type = DSO_BINARY_TYPE__KCORE;
1122
	dso__set_long_name(dso, strdup(kcore_filename), true);
1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142

	close(fd);

	if (map->type == MAP__FUNCTION)
		pr_debug("Using %s for kernel object code\n", kcore_filename);
	else
		pr_debug("Using %s for kernel data\n", kcore_filename);

	return 0;

out_err:
	while (!list_empty(&md.maps)) {
		map = list_entry(md.maps.next, struct map, node);
		list_del(&map->node);
		map__delete(map);
	}
	close(fd);
	return -EINVAL;
}

1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163
/*
 * If the kernel is relocated at boot time, kallsyms won't match.  Compute the
 * delta based on the relocation reference symbol.
 */
static int kallsyms__delta(struct map *map, const char *filename, u64 *delta)
{
	struct kmap *kmap = map__kmap(map);
	u64 addr;

	if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
		return 0;

	addr = kallsyms__get_function_start(filename,
					    kmap->ref_reloc_sym->name);
	if (!addr)
		return -1;

	*delta = addr - kmap->ref_reloc_sym->addr;
	return 0;
}

1164
int dso__load_kallsyms(struct dso *dso, const char *filename,
1165
		       struct map *map, symbol_filter_t filter)
1166
{
1167 1168
	u64 delta = 0;

1169 1170 1171
	if (symbol__restricted_filename(filename, "/proc/kallsyms"))
		return -1;

1172
	if (dso__load_all_kallsyms(dso, filename, map) < 0)
1173 1174
		return -1;

1175 1176 1177
	if (kallsyms__delta(map, filename, &delta))
		return -1;

1178
	symbols__fixup_duplicate(&dso->symbols[map->type]);
1179 1180
	symbols__fixup_end(&dso->symbols[map->type]);

1181
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1182
		dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
1183
	else
1184
		dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
1185

1186 1187 1188
	if (!dso__load_kcore(dso, map, filename))
		return dso__split_kallsyms_for_kcore(dso, map, filter);
	else
1189
		return dso__split_kallsyms(dso, map, delta, filter);
1190 1191
}

1192
static int dso__load_perf_map(struct dso *dso, struct map *map,
1193
			      symbol_filter_t filter)
1194 1195 1196 1197 1198 1199
{
	char *line = NULL;
	size_t n;
	FILE *file;
	int nr_syms = 0;

1200
	file = fopen(dso->long_name, "r");
1201 1202 1203 1204
	if (file == NULL)
		goto out_failure;

	while (!feof(file)) {
1205
		u64 start, size;
1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229
		struct symbol *sym;
		int line_len, len;

		line_len = getline(&line, &n, file);
		if (line_len < 0)
			break;

		if (!line)
			goto out_failure;

		line[--line_len] = '\0'; /* \n */

		len = hex2u64(line, &start);

		len++;
		if (len + 2 >= line_len)
			continue;

		len += hex2u64(line + len, &size);

		len++;
		if (len + 2 >= line_len)
			continue;

1230
		sym = symbol__new(start, size, STB_GLOBAL, line + len);
1231 1232 1233 1234

		if (sym == NULL)
			goto out_delete_line;

1235
		if (filter && filter(map, sym))
1236
			symbol__delete(sym);
1237
		else {
1238
			symbols__insert(&dso->symbols[map->type], sym);
1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253
			nr_syms++;
		}
	}

	free(line);
	fclose(file);

	return nr_syms;

out_delete_line:
	free(line);
out_failure:
	return -1;
}

1254
int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
1255
{
1256
	char *name;
1257
	int ret = -1;
1258
	u_int i;
1259
	struct machine *machine;
1260
	char *root_dir = (char *) "";
1261 1262 1263
	int ss_pos = 0;
	struct symsrc ss_[2];
	struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
1264

1265
	dso__set_loaded(dso, map->type);
1266

1267 1268 1269 1270
	if (dso->kernel == DSO_TYPE_KERNEL)
		return dso__load_kernel_sym(dso, map, filter);
	else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
		return dso__load_guest_kernel_sym(dso, map, filter);
1271

1272 1273
	if (map->groups && map->groups->machine)
		machine = map->groups->machine;
1274
	else
1275
		machine = NULL;
1276

1277
	dso->adjust_symbols = 0;
1278

1279
	if (strncmp(dso->name, "/tmp/perf-", 10) == 0) {
1280 1281
		struct stat st;

1282
		if (lstat(dso->name, &st) < 0)
1283 1284 1285 1286 1287 1288 1289 1290
			return -1;

		if (st.st_uid && (st.st_uid != geteuid())) {
			pr_warning("File %s not owned by current user or root, "
				"ignoring it.\n", dso->name);
			return -1;
		}

1291
		ret = dso__load_perf_map(dso, map, filter);
1292 1293
		dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
					     DSO_BINARY_TYPE__NOT_FOUND;
1294 1295 1296
		return ret;
	}

1297 1298 1299
	if (machine)
		root_dir = machine->root_dir;

1300 1301 1302 1303
	name = malloc(PATH_MAX);
	if (!name)
		return -1;

1304
	/* Iterate over candidate debug images.
1305 1306
	 * Keep track of "interesting" ones (those which have a symtab, dynsym,
	 * and/or opd section) for processing.
1307
	 */
1308
	for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
1309 1310
		struct symsrc *ss = &ss_[ss_pos];
		bool next_slot = false;
1311

1312
		enum dso_binary_type symtab_type = binary_type_symtab[i];
1313

1314 1315
		if (dso__read_binary_type_filename(dso, symtab_type,
						   root_dir, name, PATH_MAX))
1316
			continue;
1317 1318

		/* Name is now the name of the next image to try */
1319
		if (symsrc__init(ss, dso, name, symtab_type) < 0)
1320
			continue;
1321

1322 1323 1324
		if (!syms_ss && symsrc__has_symtab(ss)) {
			syms_ss = ss;
			next_slot = true;
1325 1326
			if (!dso->symsrc_filename)
				dso->symsrc_filename = strdup(name);
1327 1328
		}

1329 1330 1331
		if (!runtime_ss && symsrc__possibly_runtime(ss)) {
			runtime_ss = ss;
			next_slot = true;
1332
		}
1333

1334 1335
		if (next_slot) {
			ss_pos++;
1336

1337 1338
			if (syms_ss && runtime_ss)
				break;
1339
		}
1340

1341
	}
1342

1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353
	if (!runtime_ss && !syms_ss)
		goto out_free;

	if (runtime_ss && !syms_ss) {
		syms_ss = runtime_ss;
	}

	/* We'll have to hope for the best */
	if (!runtime_ss && syms_ss)
		runtime_ss = syms_ss;

1354 1355 1356 1357 1358 1359 1360
	if (syms_ss) {
		int km;

		km = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
		     dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE;
		ret = dso__load_sym(dso, map, syms_ss, runtime_ss, filter, km);
	} else {
1361
		ret = -1;
1362
	}
1363

1364
	if (ret > 0) {
1365 1366 1367 1368 1369
		int nr_plt;

		nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss, map, filter);
		if (nr_plt > 0)
			ret += nr_plt;
1370 1371
	}

1372 1373 1374
	for (; ss_pos > 0; ss_pos--)
		symsrc__destroy(&ss_[ss_pos - 1]);
out_free:
1375
	free(name);
1376
	if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
1377
		return 0;
1378 1379 1380
	return ret;
}

1381
struct map *map_groups__find_by_name(struct map_groups *mg,
1382
				     enum map_type type, const char *name)
1383 1384 1385
{
	struct rb_node *nd;

1386
	for (nd = rb_first(&mg->maps[type]); nd; nd = rb_next(nd)) {
1387 1388
		struct map *map = rb_entry(nd, struct map, rb_node);

1389
		if (map->dso && strcmp(map->dso->short_name, name) == 0)
1390 1391 1392 1393 1394 1395
			return map;
	}

	return NULL;
}

1396
int dso__load_vmlinux(struct dso *dso, struct map *map,
1397 1398
		      const char *vmlinux, bool vmlinux_allocated,
		      symbol_filter_t filter)
1399
{
1400 1401
	int err = -1;
	struct symsrc ss;
1402
	char symfs_vmlinux[PATH_MAX];
1403
	enum dso_binary_type symtab_type;
1404

1405 1406 1407 1408 1409
	if (vmlinux[0] == '/')
		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
	else
		snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s%s",
			 symbol_conf.symfs, vmlinux);
1410

1411
	if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1412
		symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1413
	else
1414
		symtab_type = DSO_BINARY_TYPE__VMLINUX;
1415

1416
	if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
1417 1418
		return -1;

1419
	err = dso__load_sym(dso, map, &ss, &ss, filter, 0);
1420
	symsrc__destroy(&ss);
1421

1422
	if (err > 0) {
1423
		if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
1424
			dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
1425
		else
1426
			dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
1427
		dso__set_long_name(dso, vmlinux, vmlinux_allocated);
1428
		dso__set_loaded(dso, map->type);
1429
		pr_debug("Using %s for symbols\n", symfs_vmlinux);
1430
	}
1431

1432 1433 1434
	return err;
}

1435
int dso__load_vmlinux_path(struct dso *dso, struct map *map,
1436
			   symbol_filter_t filter)
1437 1438
{
	int i, err = 0;
1439
	char *filename;
1440 1441

	pr_debug("Looking at the vmlinux_path (%d entries long)\n",
1442 1443
		 vmlinux_path__nr_entries + 1);

1444
	filename = dso__build_id_filename(dso, NULL, 0);
1445
	if (filename != NULL) {
1446 1447
		err = dso__load_vmlinux(dso, map, filename, true, filter);
		if (err > 0)
1448 1449 1450
			goto out;
		free(filename);
	}
1451 1452

	for (i = 0; i < vmlinux_path__nr_entries; ++i) {
1453 1454
		err = dso__load_vmlinux(dso, map, vmlinux_path[i], false, filter);
		if (err > 0)
1455 1456
			break;
	}
1457
out:
1458 1459 1460
	return err;
}

1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479
static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
{
	char kallsyms_filename[PATH_MAX];
	struct dirent *dent;
	int ret = -1;
	DIR *d;

	d = opendir(dir);
	if (!d)
		return -1;

	while (1) {
		dent = readdir(d);
		if (!dent)
			break;
		if (dent->d_type != DT_DIR)
			continue;
		scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
			  "%s/%s/kallsyms", dir, dent->d_name);
1480
		if (!validate_kcore_addresses(kallsyms_filename, map)) {
1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512
			strlcpy(dir, kallsyms_filename, dir_sz);
			ret = 0;
			break;
		}
	}

	closedir(d);

	return ret;
}

static char *dso__find_kallsyms(struct dso *dso, struct map *map)
{
	u8 host_build_id[BUILD_ID_SIZE];
	char sbuild_id[BUILD_ID_SIZE * 2 + 1];
	bool is_host = false;
	char path[PATH_MAX];

	if (!dso->has_build_id) {
		/*
		 * Last resort, if we don't have a build-id and couldn't find
		 * any vmlinux file, try the running kernel kallsyms table.
		 */
		goto proc_kallsyms;
	}

	if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
				 sizeof(host_build_id)) == 0)
		is_host = dso__build_id_equal(dso, host_build_id);

	build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);

1513 1514 1515
	scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", buildid_dir,
		  sbuild_id);

1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534
	/* Use /proc/kallsyms if possible */
	if (is_host) {
		DIR *d;
		int fd;

		/* If no cached kcore go with /proc/kallsyms */
		d = opendir(path);
		if (!d)
			goto proc_kallsyms;
		closedir(d);

		/*
		 * Do not check the build-id cache, until we know we cannot use
		 * /proc/kcore.
		 */
		fd = open("/proc/kcore", O_RDONLY);
		if (fd != -1) {
			close(fd);
			/* If module maps match go with /proc/kallsyms */
1535
			if (!validate_kcore_addresses("/proc/kallsyms", map))
1536 1537 1538 1539 1540 1541 1542 1543 1544 1545
				goto proc_kallsyms;
		}

		/* Find kallsyms in build-id cache with kcore */
		if (!find_matching_kcore(map, path, sizeof(path)))
			return strdup(path);

		goto proc_kallsyms;
	}

1546 1547 1548 1549
	/* Find kallsyms in build-id cache with kcore */
	if (!find_matching_kcore(map, path, sizeof(path)))
		return strdup(path);

1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564
	scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s",
		  buildid_dir, sbuild_id);

	if (access(path, F_OK)) {
		pr_err("No kallsyms or vmlinux with build-id %s was found\n",
		       sbuild_id);
		return NULL;
	}

	return strdup(path);

proc_kallsyms:
	return strdup("/proc/kallsyms");
}

1565
static int dso__load_kernel_sym(struct dso *dso, struct map *map,
1566
				symbol_filter_t filter)
1567
{
1568
	int err;
1569 1570
	const char *kallsyms_filename = NULL;
	char *kallsyms_allocated_filename = NULL;
1571
	/*
1572 1573
	 * Step 1: if the user specified a kallsyms or vmlinux filename, use
	 * it and only it, reporting errors to the user if it cannot be used.
1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585
	 *
	 * For instance, try to analyse an ARM perf.data file _without_ a
	 * build-id, or if the user specifies the wrong path to the right
	 * vmlinux file, obviously we can't fallback to another vmlinux (a
	 * x86_86 one, on the machine where analysis is being performed, say),
	 * or worse, /proc/kallsyms.
	 *
	 * If the specified file _has_ a build-id and there is a build-id
	 * section in the perf.data file, we will still do the expected
	 * validation in dso__load_vmlinux and will bail out if they don't
	 * match.
	 */
1586 1587 1588 1589 1590
	if (symbol_conf.kallsyms_name != NULL) {
		kallsyms_filename = symbol_conf.kallsyms_name;
		goto do_kallsyms;
	}

1591
	if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
1592 1593
		return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name,
					 false, filter);
1594
	}
1595

1596
	if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
1597
		err = dso__load_vmlinux_path(dso, map, filter);
1598
		if (err > 0)
1599
			return err;
1600 1601
	}

1602 1603 1604 1605
	/* do not try local files if a symfs was given */
	if (symbol_conf.symfs[0] != 0)
		return -1;

1606 1607 1608
	kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
	if (!kallsyms_allocated_filename)
		return -1;
1609

1610
	kallsyms_filename = kallsyms_allocated_filename;
1611

1612
do_kallsyms:
1613
	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1614 1615
	if (err > 0)
		pr_debug("Using %s for symbols\n", kallsyms_filename);
1616
	free(kallsyms_allocated_filename);
1617

1618
	if (err > 0 && !dso__is_kcore(dso)) {
1619
		dso__set_long_name(dso, "[kernel.kallsyms]", false);
1620 1621
		map__fixup_start(map);
		map__fixup_end(map);
1622
	}
1623

1624 1625 1626
	return err;
}

1627 1628
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map,
				      symbol_filter_t filter)
1629 1630 1631
{
	int err;
	const char *kallsyms_filename = NULL;
1632
	struct machine *machine;
1633 1634 1635 1636 1637 1638
	char path[PATH_MAX];

	if (!map->groups) {
		pr_debug("Guest kernel map hasn't the point to groups\n");
		return -1;
	}
1639
	machine = map->groups->machine;
1640

1641
	if (machine__is_default_guest(machine)) {
1642 1643 1644 1645 1646 1647
		/*
		 * if the user specified a vmlinux filename, use it and only
		 * it, reporting errors to the user if it cannot be used.
		 * Or use file guest_kallsyms inputted by user on commandline
		 */
		if (symbol_conf.default_guest_vmlinux_name != NULL) {
1648
			err = dso__load_vmlinux(dso, map,
1649 1650
						symbol_conf.default_guest_vmlinux_name,
						false, filter);
1651
			return err;
1652 1653 1654 1655 1656 1657
		}

		kallsyms_filename = symbol_conf.default_guest_kallsyms;
		if (!kallsyms_filename)
			return -1;
	} else {
1658
		sprintf(path, "%s/proc/kallsyms", machine->root_dir);
1659 1660 1661
		kallsyms_filename = path;
	}

1662
	err = dso__load_kallsyms(dso, kallsyms_filename, map, filter);
1663
	if (err > 0)
1664
		pr_debug("Using %s for symbols\n", kallsyms_filename);
1665
	if (err > 0 && !dso__is_kcore(dso)) {
1666
		machine__mmap_name(machine, path, sizeof(path));
1667
		dso__set_long_name(dso, strdup(path), true);
1668 1669 1670 1671 1672 1673
		map__fixup_start(map);
		map__fixup_end(map);
	}

	return err;
}
1674

1675 1676
static void vmlinux_path__exit(void)
{
1677 1678
	while (--vmlinux_path__nr_entries >= 0)
		zfree(&vmlinux_path[vmlinux_path__nr_entries]);
1679

1680
	zfree(&vmlinux_path);
1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699
}

static int vmlinux_path__init(void)
{
	struct utsname uts;
	char bf[PATH_MAX];

	vmlinux_path = malloc(sizeof(char *) * 5);
	if (vmlinux_path == NULL)
		return -1;

	vmlinux_path[vmlinux_path__nr_entries] = strdup("vmlinux");
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	vmlinux_path[vmlinux_path__nr_entries] = strdup("/boot/vmlinux");
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
1700 1701 1702 1703 1704 1705 1706 1707

	/* only try running kernel version if no symfs was given */
	if (symbol_conf.symfs[0] != 0)
		return 0;

	if (uname(&uts) < 0)
		return -1;

1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731
	snprintf(bf, sizeof(bf), "/boot/vmlinux-%s", uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	snprintf(bf, sizeof(bf), "/lib/modules/%s/build/vmlinux", uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;
	snprintf(bf, sizeof(bf), "/usr/lib/debug/lib/modules/%s/vmlinux",
		 uts.release);
	vmlinux_path[vmlinux_path__nr_entries] = strdup(bf);
	if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
		goto out_fail;
	++vmlinux_path__nr_entries;

	return 0;

out_fail:
	vmlinux_path__exit();
	return -1;
}

D
David Ahern 已提交
1732
int setup_list(struct strlist **list, const char *list_str,
1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745
		      const char *list_name)
{
	if (list_str == NULL)
		return 0;

	*list = strlist__new(true, list_str);
	if (!*list) {
		pr_err("problems parsing %s list\n", list_name);
		return -1;
	}
	return 0;
}

1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764
static bool symbol__read_kptr_restrict(void)
{
	bool value = false;

	if (geteuid() != 0) {
		FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
		if (fp != NULL) {
			char line[8];

			if (fgets(line, sizeof(line), fp) != NULL)
				value = atoi(line) != 0;

			fclose(fp);
		}
	}

	return value;
}

1765
int symbol__init(void)
1766
{
1767 1768
	const char *symfs;

1769 1770 1771
	if (symbol_conf.initialized)
		return 0;

1772
	symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
1773

1774 1775
	symbol__elf_init();

1776 1777 1778
	if (symbol_conf.sort_by_name)
		symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
					  sizeof(struct symbol));
1779

1780
	if (symbol_conf.try_vmlinux_path && vmlinux_path__init() < 0)
1781 1782
		return -1;

1783 1784 1785 1786 1787
	if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
		pr_err("'.' is the only non valid --field-separator argument\n");
		return -1;
	}

1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799
	if (setup_list(&symbol_conf.dso_list,
		       symbol_conf.dso_list_str, "dso") < 0)
		return -1;

	if (setup_list(&symbol_conf.comm_list,
		       symbol_conf.comm_list_str, "comm") < 0)
		goto out_free_dso_list;

	if (setup_list(&symbol_conf.sym_list,
		       symbol_conf.sym_list_str, "symbol") < 0)
		goto out_free_comm_list;

1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811
	/*
	 * A path to symbols of "/" is identical to ""
	 * reset here for simplicity.
	 */
	symfs = realpath(symbol_conf.symfs, NULL);
	if (symfs == NULL)
		symfs = symbol_conf.symfs;
	if (strcmp(symfs, "/") == 0)
		symbol_conf.symfs = "";
	if (symfs != symbol_conf.symfs)
		free((void *)symfs);

1812 1813
	symbol_conf.kptr_restrict = symbol__read_kptr_restrict();

1814
	symbol_conf.initialized = true;
1815
	return 0;
1816 1817 1818

out_free_comm_list:
	strlist__delete(symbol_conf.comm_list);
1819 1820
out_free_dso_list:
	strlist__delete(symbol_conf.dso_list);
1821
	return -1;
1822 1823
}

1824 1825
void symbol__exit(void)
{
1826 1827
	if (!symbol_conf.initialized)
		return;
1828 1829 1830 1831 1832
	strlist__delete(symbol_conf.sym_list);
	strlist__delete(symbol_conf.dso_list);
	strlist__delete(symbol_conf.comm_list);
	vmlinux_path__exit();
	symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
1833
	symbol_conf.initialized = false;
1834
}