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-rw-r--r--tools/objtool/elf.c113
-rw-r--r--tools/objtool/include/objtool/elf.h17
2 files changed, 83 insertions, 47 deletions
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index d08f5f3670f8..a8a0ee21f71a 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -9,6 +9,7 @@
#include <sys/types.h>
#include <sys/stat.h>
+#include <sys/mman.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
@@ -27,21 +28,27 @@ static inline u32 str_hash(const char *str)
return jhash(str, strlen(str), 0);
}
-static inline int elf_hash_bits(void)
-{
- return vmlinux ? ELF_HASH_BITS : 16;
-}
+#define __elf_table(name) (elf->name##_hash)
+#define __elf_bits(name) (elf->name##_bits)
-#define elf_hash_add(hashtable, node, key) \
- hlist_add_head(node, &hashtable[hash_min(key, elf_hash_bits())])
+#define elf_hash_add(name, node, key) \
+ hlist_add_head(node, &__elf_table(name)[hash_min(key, __elf_bits(name))])
-static void elf_hash_init(struct hlist_head *table)
-{
- __hash_init(table, 1U << elf_hash_bits());
-}
+#define elf_hash_for_each_possible(name, obj, member, key) \
+ hlist_for_each_entry(obj, &__elf_table(name)[hash_min(key, __elf_bits(name))], member)
-#define elf_hash_for_each_possible(name, obj, member, key) \
- hlist_for_each_entry(obj, &name[hash_min(key, elf_hash_bits())], member)
+#define elf_alloc_hash(name, size) \
+({ \
+ __elf_bits(name) = max(10, ilog2(size)); \
+ __elf_table(name) = mmap(NULL, sizeof(struct hlist_head) << __elf_bits(name), \
+ PROT_READ|PROT_WRITE, \
+ MAP_PRIVATE|MAP_ANON, -1, 0); \
+ if (__elf_table(name) == (void *)-1L) { \
+ WARN("mmap fail " #name); \
+ __elf_table(name) = NULL; \
+ } \
+ __elf_table(name); \
+})
static bool symbol_to_offset(struct rb_node *a, const struct rb_node *b)
{
@@ -80,9 +87,10 @@ struct section *find_section_by_name(const struct elf *elf, const char *name)
{
struct section *sec;
- elf_hash_for_each_possible(elf->section_name_hash, sec, name_hash, str_hash(name))
+ elf_hash_for_each_possible(section_name, sec, name_hash, str_hash(name)) {
if (!strcmp(sec->name, name))
return sec;
+ }
return NULL;
}
@@ -92,9 +100,10 @@ static struct section *find_section_by_index(struct elf *elf,
{
struct section *sec;
- elf_hash_for_each_possible(elf->section_hash, sec, hash, idx)
+ elf_hash_for_each_possible(section, sec, hash, idx) {
if (sec->idx == idx)
return sec;
+ }
return NULL;
}
@@ -103,9 +112,10 @@ static struct symbol *find_symbol_by_index(struct elf *elf, unsigned int idx)
{
struct symbol *sym;
- elf_hash_for_each_possible(elf->symbol_hash, sym, hash, idx)
+ elf_hash_for_each_possible(symbol, sym, hash, idx) {
if (sym->idx == idx)
return sym;
+ }
return NULL;
}
@@ -170,9 +180,10 @@ struct symbol *find_symbol_by_name(const struct elf *elf, const char *name)
{
struct symbol *sym;
- elf_hash_for_each_possible(elf->symbol_name_hash, sym, name_hash, str_hash(name))
+ elf_hash_for_each_possible(symbol_name, sym, name_hash, str_hash(name)) {
if (!strcmp(sym->name, name))
return sym;
+ }
return NULL;
}
@@ -189,8 +200,8 @@ struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *se
sec = sec->reloc;
for_offset_range(o, offset, offset + len) {
- elf_hash_for_each_possible(elf->reloc_hash, reloc, hash,
- sec_offset_hash(sec, o)) {
+ elf_hash_for_each_possible(reloc, reloc, hash,
+ sec_offset_hash(sec, o)) {
if (reloc->sec != sec)
continue;
@@ -228,6 +239,10 @@ static int read_sections(struct elf *elf)
return -1;
}
+ if (!elf_alloc_hash(section, sections_nr) ||
+ !elf_alloc_hash(section_name, sections_nr))
+ return -1;
+
for (i = 0; i < sections_nr; i++) {
sec = malloc(sizeof(*sec));
if (!sec) {
@@ -274,12 +289,14 @@ static int read_sections(struct elf *elf)
sec->len = sec->sh.sh_size;
list_add_tail(&sec->list, &elf->sections);
- elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
- elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
+ elf_hash_add(section, &sec->hash, sec->idx);
+ elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
}
- if (stats)
+ if (stats) {
printf("nr_sections: %lu\n", (unsigned long)sections_nr);
+ printf("section_bits: %d\n", elf->section_bits);
+ }
/* sanity check, one more call to elf_nextscn() should return NULL */
if (elf_nextscn(elf->elf, s)) {
@@ -308,8 +325,8 @@ static void elf_add_symbol(struct elf *elf, struct symbol *sym)
else
entry = &sym->sec->symbol_list;
list_add(&sym->list, entry);
- elf_hash_add(elf->symbol_hash, &sym->hash, sym->idx);
- elf_hash_add(elf->symbol_name_hash, &sym->name_hash, str_hash(sym->name));
+ elf_hash_add(symbol, &sym->hash, sym->idx);
+ elf_hash_add(symbol_name, &sym->name_hash, str_hash(sym->name));
/*
* Don't store empty STT_NOTYPE symbols in the rbtree. They
@@ -329,19 +346,25 @@ static int read_symbols(struct elf *elf)
Elf32_Word shndx;
symtab = find_section_by_name(elf, ".symtab");
- if (!symtab) {
+ if (symtab) {
+ symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
+ if (symtab_shndx)
+ shndx_data = symtab_shndx->data;
+
+ symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
+ } else {
/*
* A missing symbol table is actually possible if it's an empty
- * .o file. This can happen for thunk_64.o.
+ * .o file. This can happen for thunk_64.o. Make sure to at
+ * least allocate the symbol hash tables so we can do symbol
+ * lookups without crashing.
*/
- return 0;
+ symbols_nr = 0;
}
- symtab_shndx = find_section_by_name(elf, ".symtab_shndx");
- if (symtab_shndx)
- shndx_data = symtab_shndx->data;
-
- symbols_nr = symtab->sh.sh_size / symtab->sh.sh_entsize;
+ if (!elf_alloc_hash(symbol, symbols_nr) ||
+ !elf_alloc_hash(symbol_name, symbols_nr))
+ return -1;
for (i = 0; i < symbols_nr; i++) {
sym = malloc(sizeof(*sym));
@@ -389,8 +412,10 @@ static int read_symbols(struct elf *elf)
elf_add_symbol(elf, sym);
}
- if (stats)
+ if (stats) {
printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
+ printf("symbol_bits: %d\n", elf->symbol_bits);
+ }
/* Create parent/child links for any cold subfunctions */
list_for_each_entry(sec, &elf->sections, list) {
@@ -479,7 +504,7 @@ int elf_add_reloc(struct elf *elf, struct section *sec, unsigned long offset,
reloc->addend = addend;
list_add_tail(&reloc->list, &sec->reloc->reloc_list);
- elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+ elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
sec->reloc->changed = true;
@@ -556,6 +581,15 @@ static int read_relocs(struct elf *elf)
unsigned int symndx;
unsigned long nr_reloc, max_reloc = 0, tot_reloc = 0;
+ sec = find_section_by_name(elf, ".text");
+ if (!sec) {
+ WARN("no .text");
+ return -1;
+ }
+
+ if (!elf_alloc_hash(reloc, sec->len / 16))
+ return -1;
+
list_for_each_entry(sec, &elf->sections, list) {
if ((sec->sh.sh_type != SHT_RELA) &&
(sec->sh.sh_type != SHT_REL))
@@ -600,7 +634,7 @@ static int read_relocs(struct elf *elf)
}
list_add_tail(&reloc->list, &sec->reloc_list);
- elf_hash_add(elf->reloc_hash, &reloc->hash, reloc_hash(reloc));
+ elf_hash_add(reloc, &reloc->hash, reloc_hash(reloc));
nr_reloc++;
}
@@ -611,6 +645,7 @@ static int read_relocs(struct elf *elf)
if (stats) {
printf("max_reloc: %lu\n", max_reloc);
printf("tot_reloc: %lu\n", tot_reloc);
+ printf("reloc_bits: %d\n", elf->reloc_bits);
}
return 0;
@@ -632,12 +667,6 @@ struct elf *elf_open_read(const char *name, int flags)
INIT_LIST_HEAD(&elf->sections);
- elf_hash_init(elf->symbol_hash);
- elf_hash_init(elf->symbol_name_hash);
- elf_hash_init(elf->section_hash);
- elf_hash_init(elf->section_name_hash);
- elf_hash_init(elf->reloc_hash);
-
elf->fd = open(name, flags);
if (elf->fd == -1) {
fprintf(stderr, "objtool: Can't open '%s': %s\n",
@@ -850,8 +879,8 @@ struct section *elf_create_section(struct elf *elf, const char *name,
return NULL;
list_add_tail(&sec->list, &elf->sections);
- elf_hash_add(elf->section_hash, &sec->hash, sec->idx);
- elf_hash_add(elf->section_name_hash, &sec->name_hash, str_hash(sec->name));
+ elf_hash_add(section, &sec->hash, sec->idx);
+ elf_hash_add(section_name, &sec->name_hash, str_hash(sec->name));
elf->changed = true;
diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index 45e5ede363b0..90082751f851 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -84,11 +84,18 @@ struct elf {
bool changed;
char *name;
struct list_head sections;
- DECLARE_HASHTABLE(symbol_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(symbol_name_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(section_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(section_name_hash, ELF_HASH_BITS);
- DECLARE_HASHTABLE(reloc_hash, ELF_HASH_BITS);
+
+ int symbol_bits;
+ int symbol_name_bits;
+ int section_bits;
+ int section_name_bits;
+ int reloc_bits;
+
+ struct hlist_head *symbol_hash;
+ struct hlist_head *symbol_name_hash;
+ struct hlist_head *section_hash;
+ struct hlist_head *section_name_hash;
+ struct hlist_head *reloc_hash;
};
#define OFFSET_STRIDE_BITS 4
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-04 19:12:32 +0100