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-rw-r--r--scripts/kallsyms.c287
1 files changed, 142 insertions, 145 deletions
diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c
index ae6504d07fd6..fb55f262f42d 100644
--- a/scripts/kallsyms.c
+++ b/scripts/kallsyms.c
@@ -18,15 +18,14 @@
*
*/
+#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <limits.h>
-#ifndef ARRAY_SIZE
#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
-#endif
#define KSYM_NAME_LEN 128
@@ -58,9 +57,9 @@ static struct addr_range percpu_range = {
static struct sym_entry *table;
static unsigned int table_size, table_cnt;
-static int all_symbols = 0;
-static int absolute_percpu = 0;
-static int base_relative = 0;
+static int all_symbols;
+static int absolute_percpu;
+static int base_relative;
static int token_profit[0x10000];
@@ -76,18 +75,88 @@ static void usage(void)
exit(1);
}
-/*
- * This ignores the intensely annoying "mapping symbols" found
- * in ARM ELF files: $a, $t and $d.
- */
-static int is_arm_mapping_symbol(const char *str)
+static char *sym_name(const struct sym_entry *s)
+{
+ return (char *)s->sym + 1;
+}
+
+static bool is_ignored_symbol(const char *name, char type)
{
- return str[0] == '$' && strchr("axtd", str[1])
- && (str[2] == '\0' || str[2] == '.');
+ static const char * const ignored_symbols[] = {
+ /*
+ * Symbols which vary between passes. Passes 1 and 2 must have
+ * identical symbol lists. The kallsyms_* symbols below are
+ * only added after pass 1, they would be included in pass 2
+ * when --all-symbols is specified so exclude them to get a
+ * stable symbol list.
+ */
+ "kallsyms_addresses",
+ "kallsyms_offsets",
+ "kallsyms_relative_base",
+ "kallsyms_num_syms",
+ "kallsyms_names",
+ "kallsyms_markers",
+ "kallsyms_token_table",
+ "kallsyms_token_index",
+ /* Exclude linker generated symbols which vary between passes */
+ "_SDA_BASE_", /* ppc */
+ "_SDA2_BASE_", /* ppc */
+ NULL
+ };
+
+ static const char * const ignored_prefixes[] = {
+ "$", /* local symbols for ARM, MIPS, etc. */
+ ".LASANPC", /* s390 kasan local symbols */
+ "__crc_", /* modversions */
+ "__efistub_", /* arm64 EFI stub namespace */
+ NULL
+ };
+
+ static const char * const ignored_suffixes[] = {
+ "_from_arm", /* arm */
+ "_from_thumb", /* arm */
+ "_veneer", /* arm */
+ NULL
+ };
+
+ const char * const *p;
+
+ /* Exclude symbols which vary between passes. */
+ for (p = ignored_symbols; *p; p++)
+ if (!strcmp(name, *p))
+ return true;
+
+ for (p = ignored_prefixes; *p; p++)
+ if (!strncmp(name, *p, strlen(*p)))
+ return true;
+
+ for (p = ignored_suffixes; *p; p++) {
+ int l = strlen(name) - strlen(*p);
+
+ if (l >= 0 && !strcmp(name + l, *p))
+ return true;
+ }
+
+ if (type == 'U' || type == 'u')
+ return true;
+ /* exclude debugging symbols */
+ if (type == 'N' || type == 'n')
+ return true;
+
+ if (toupper(type) == 'A') {
+ /* Keep these useful absolute symbols */
+ if (strcmp(name, "__kernel_syscall_via_break") &&
+ strcmp(name, "__kernel_syscall_via_epc") &&
+ strcmp(name, "__kernel_sigtramp") &&
+ strcmp(name, "__gp"))
+ return true;
+ }
+
+ return false;
}
-static int check_symbol_range(const char *sym, unsigned long long addr,
- struct addr_range *ranges, int entries)
+static void check_symbol_range(const char *sym, unsigned long long addr,
+ struct addr_range *ranges, int entries)
{
size_t i;
struct addr_range *ar;
@@ -97,14 +166,12 @@ static int check_symbol_range(const char *sym, unsigned long long addr,
if (strcmp(sym, ar->start_sym) == 0) {
ar->start = addr;
- return 0;
+ return;
} else if (strcmp(sym, ar->end_sym) == 0) {
ar->end = addr;
- return 0;
+ return;
}
}
-
- return 1;
}
static int read_symbol(FILE *in, struct sym_entry *s)
@@ -125,34 +192,15 @@ static int read_symbol(FILE *in, struct sym_entry *s)
return -1;
}
+ if (is_ignored_symbol(sym, stype))
+ return -1;
+
/* Ignore most absolute/undefined (?) symbols. */
if (strcmp(sym, "_text") == 0)
_text = s->addr;
- else if (check_symbol_range(sym, s->addr, text_ranges,
- ARRAY_SIZE(text_ranges)) == 0)
- /* nothing to do */;
- else if (toupper(stype) == 'A')
- {
- /* Keep these useful absolute symbols */
- if (strcmp(sym, "__kernel_syscall_via_break") &&
- strcmp(sym, "__kernel_syscall_via_epc") &&
- strcmp(sym, "__kernel_sigtramp") &&
- strcmp(sym, "__gp"))
- return -1;
- }
- else if (toupper(stype) == 'U' ||
- is_arm_mapping_symbol(sym))
- return -1;
- /* exclude also MIPS ELF local symbols ($L123 instead of .L123) */
- else if (sym[0] == '$')
- return -1;
- /* exclude debugging symbols */
- else if (stype == 'N' || stype == 'n')
- return -1;
- /* exclude s390 kasan local symbols */
- else if (!strncmp(sym, ".LASANPC", 8))
- return -1;
+ check_symbol_range(sym, s->addr, text_ranges, ARRAY_SIZE(text_ranges));
+ check_symbol_range(sym, s->addr, &percpu_range, 1);
/* include the type field in the symbol name, so that it gets
* compressed together */
@@ -163,22 +211,19 @@ static int read_symbol(FILE *in, struct sym_entry *s)
"unable to allocate required amount of memory\n");
exit(EXIT_FAILURE);
}
- strcpy((char *)s->sym + 1, sym);
+ strcpy(sym_name(s), sym);
s->sym[0] = stype;
s->percpu_absolute = 0;
- /* Record if we've found __per_cpu_start/end. */
- check_symbol_range(sym, s->addr, &percpu_range, 1);
-
return 0;
}
-static int symbol_in_range(struct sym_entry *s, struct addr_range *ranges,
- int entries)
+static int symbol_in_range(const struct sym_entry *s,
+ const struct addr_range *ranges, int entries)
{
size_t i;
- struct addr_range *ar;
+ const struct addr_range *ar;
for (i = 0; i < entries; ++i) {
ar = &ranges[i];
@@ -190,41 +235,9 @@ static int symbol_in_range(struct sym_entry *s, struct addr_range *ranges,
return 0;
}
-static int symbol_valid(struct sym_entry *s)
+static int symbol_valid(const struct sym_entry *s)
{
- /* Symbols which vary between passes. Passes 1 and 2 must have
- * identical symbol lists. The kallsyms_* symbols below are only added
- * after pass 1, they would be included in pass 2 when --all-symbols is
- * specified so exclude them to get a stable symbol list.
- */
- static char *special_symbols[] = {
- "kallsyms_addresses",
- "kallsyms_offsets",
- "kallsyms_relative_base",
- "kallsyms_num_syms",
- "kallsyms_names",
- "kallsyms_markers",
- "kallsyms_token_table",
- "kallsyms_token_index",
-
- /* Exclude linker generated symbols which vary between passes */
- "_SDA_BASE_", /* ppc */
- "_SDA2_BASE_", /* ppc */
- NULL };
-
- static char *special_prefixes[] = {
- "__crc_", /* modversions */
- "__efistub_", /* arm64 EFI stub namespace */
- NULL };
-
- static char *special_suffixes[] = {
- "_veneer", /* arm */
- "_from_arm", /* arm */
- "_from_thumb", /* arm */
- NULL };
-
- int i;
- char *sym_name = (char *)s->sym + 1;
+ const char *name = sym_name(s);
/* if --all-symbols is not specified, then symbols outside the text
* and inittext sections are discarded */
@@ -239,35 +252,37 @@ static int symbol_valid(struct sym_entry *s)
* rules.
*/
if ((s->addr == text_range_text->end &&
- strcmp(sym_name,
- text_range_text->end_sym)) ||
+ strcmp(name, text_range_text->end_sym)) ||
(s->addr == text_range_inittext->end &&
- strcmp(sym_name,
- text_range_inittext->end_sym)))
+ strcmp(name, text_range_inittext->end_sym)))
return 0;
}
- /* Exclude symbols which vary between passes. */
- for (i = 0; special_symbols[i]; i++)
- if (strcmp(sym_name, special_symbols[i]) == 0)
- return 0;
+ return 1;
+}
- for (i = 0; special_prefixes[i]; i++) {
- int l = strlen(special_prefixes[i]);
+/* remove all the invalid symbols from the table */
+static void shrink_table(void)
+{
+ unsigned int i, pos;
- if (l <= strlen(sym_name) &&
- strncmp(sym_name, special_prefixes[i], l) == 0)
- return 0;
+ pos = 0;
+ for (i = 0; i < table_cnt; i++) {
+ if (symbol_valid(&table[i])) {
+ if (pos != i)
+ table[pos] = table[i];
+ pos++;
+ } else {
+ free(table[i].sym);
+ }
}
+ table_cnt = pos;
- for (i = 0; special_suffixes[i]; i++) {
- int l = strlen(sym_name) - strlen(special_suffixes[i]);
-
- if (l >= 0 && strcmp(sym_name + l, special_suffixes[i]) == 0)
- return 0;
+ /* When valid symbol is not registered, exit to error */
+ if (!table_cnt) {
+ fprintf(stderr, "No valid symbol.\n");
+ exit(1);
}
-
- return 1;
}
static void read_map(FILE *in)
@@ -288,7 +303,7 @@ static void read_map(FILE *in)
}
}
-static void output_label(char *label)
+static void output_label(const char *label)
{
printf(".globl %s\n", label);
printf("\tALGN\n");
@@ -297,7 +312,7 @@ static void output_label(char *label)
/* uncompress a compressed symbol. When this function is called, the best table
* might still be compressed itself, so the function needs to be recursive */
-static int expand_symbol(unsigned char *data, int len, char *result)
+static int expand_symbol(const unsigned char *data, int len, char *result)
{
int c, rlen, total=0;
@@ -322,7 +337,7 @@ static int expand_symbol(unsigned char *data, int len, char *result)
return total;
}
-static int symbol_absolute(struct sym_entry *s)
+static int symbol_absolute(const struct sym_entry *s)
{
return s->percpu_absolute;
}
@@ -460,7 +475,7 @@ static void write_src(void)
/* table lookup compression functions */
/* count all the possible tokens in a symbol */
-static void learn_symbol(unsigned char *symbol, int len)
+static void learn_symbol(const unsigned char *symbol, int len)
{
int i;
@@ -469,7 +484,7 @@ static void learn_symbol(unsigned char *symbol, int len)
}
/* decrease the count for all the possible tokens in a symbol */
-static void forget_symbol(unsigned char *symbol, int len)
+static void forget_symbol(const unsigned char *symbol, int len)
{
int i;
@@ -477,24 +492,17 @@ static void forget_symbol(unsigned char *symbol, int len)
token_profit[ symbol[i] + (symbol[i + 1] << 8) ]--;
}
-/* remove all the invalid symbols from the table and do the initial token count */
+/* do the initial token count */
static void build_initial_tok_table(void)
{
- unsigned int i, pos;
+ unsigned int i;
- pos = 0;
- for (i = 0; i < table_cnt; i++) {
- if ( symbol_valid(&table[i]) ) {
- if (pos != i)
- table[pos] = table[i];
- learn_symbol(table[pos].sym, table[pos].len);
- pos++;
- }
- }
- table_cnt = pos;
+ for (i = 0; i < table_cnt; i++)
+ learn_symbol(table[i].sym, table[i].len);
}
-static void *find_token(unsigned char *str, int len, unsigned char *token)
+static unsigned char *find_token(unsigned char *str, int len,
+ const unsigned char *token)
{
int i;
@@ -507,7 +515,7 @@ static void *find_token(unsigned char *str, int len, unsigned char *token)
/* replace a given token in all the valid symbols. Use the sampled symbols
* to update the counts */
-static void compress_symbols(unsigned char *str, int idx)
+static void compress_symbols(const unsigned char *str, int idx)
{
unsigned int i, len, size;
unsigned char *p1, *p2;
@@ -614,19 +622,13 @@ static void optimize_token_table(void)
insert_real_symbols_in_table();
- /* When valid symbol is not registered, exit to error */
- if (!table_cnt) {
- fprintf(stderr, "No valid symbol.\n");
- exit(1);
- }
-
optimize_result();
}
/* guess for "linker script provide" symbol */
static int may_be_linker_script_provide_symbol(const struct sym_entry *se)
{
- const char *symbol = (char *)se->sym + 1;
+ const char *symbol = sym_name(se);
int len = se->len - 1;
if (len < 8)
@@ -658,16 +660,6 @@ static int may_be_linker_script_provide_symbol(const struct sym_entry *se)
return 0;
}
-static int prefix_underscores_count(const char *str)
-{
- const char *tail = str;
-
- while (*tail == '_')
- tail++;
-
- return tail - str;
-}
-
static int compare_symbols(const void *a, const void *b)
{
const struct sym_entry *sa;
@@ -696,8 +688,8 @@ static int compare_symbols(const void *a, const void *b)
return wa - wb;
/* sort by the number of prefix underscores */
- wa = prefix_underscores_count((const char *)sa->sym + 1);
- wb = prefix_underscores_count((const char *)sb->sym + 1);
+ wa = strspn(sym_name(sa), "_");
+ wb = strspn(sym_name(sb), "_");
if (wa != wb)
return wa - wb;
@@ -731,11 +723,15 @@ static void record_relative_base(void)
{
unsigned int i;
- relative_base = -1ULL;
for (i = 0; i < table_cnt; i++)
- if (!symbol_absolute(&table[i]) &&
- table[i].addr < relative_base)
+ if (!symbol_absolute(&table[i])) {
+ /*
+ * The table is sorted by address.
+ * Take the first non-absolute symbol value.
+ */
relative_base = table[i].addr;
+ return;
+ }
}
int main(int argc, char **argv)
@@ -756,11 +752,12 @@ int main(int argc, char **argv)
usage();
read_map(stdin);
+ shrink_table();
if (absolute_percpu)
make_percpus_absolute();
+ sort_symbols();
if (base_relative)
record_relative_base();
- sort_symbols();
optimize_token_table();
write_src();