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modpost.c
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modpost.c
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/* Postprocess module symbol versions
*
* Copyright 2003 Kai Germaschewski
* Copyright 2002-2004 Rusty Russell, IBM Corporation
* Copyright 2006-2008 Sam Ravnborg
* Based in part on module-init-tools/depmod.c,file2alias
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
* Usage: modpost vmlinux module1.o module2.o ...
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include "modpost.h"
#include "../../include/generated/autoconf.h"
#include "../../include/linux/license.h"
/* Some toolchains use a `_' prefix for all user symbols. */
#ifdef CONFIG_SYMBOL_PREFIX
#define MODULE_SYMBOL_PREFIX CONFIG_SYMBOL_PREFIX
#else
#define MODULE_SYMBOL_PREFIX ""
#endif
/* Are we using CONFIG_MODVERSIONS? */
int modversions = 0;
/* Warn about undefined symbols? (do so if we have vmlinux) */
int have_vmlinux = 0;
/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
static int all_versions = 0;
/* If we are modposting external module set to 1 */
static int external_module = 0;
/* Warn about section mismatch in vmlinux if set to 1 */
static int vmlinux_section_warnings = 1;
/* Only warn about unresolved symbols */
static int warn_unresolved = 0;
/* How a symbol is exported */
static int sec_mismatch_count = 0;
static int sec_mismatch_verbose = 1;
enum export {
export_plain, export_unused, export_gpl,
export_unused_gpl, export_gpl_future, export_unknown
};
#define PRINTF __attribute__ ((format (printf, 1, 2)))
PRINTF void fatal(const char *fmt, ...)
{
va_list arglist;
fprintf(stderr, "FATAL: ");
va_start(arglist, fmt);
vfprintf(stderr, fmt, arglist);
va_end(arglist);
exit(1);
}
PRINTF void warn(const char *fmt, ...)
{
va_list arglist;
fprintf(stderr, "WARNING: ");
va_start(arglist, fmt);
vfprintf(stderr, fmt, arglist);
va_end(arglist);
}
PRINTF void merror(const char *fmt, ...)
{
va_list arglist;
fprintf(stderr, "ERROR: ");
va_start(arglist, fmt);
vfprintf(stderr, fmt, arglist);
va_end(arglist);
}
static int is_vmlinux(const char *modname)
{
const char *myname;
myname = strrchr(modname, '/');
if (myname)
myname++;
else
myname = modname;
return (strcmp(myname, "vmlinux") == 0) ||
(strcmp(myname, "vmlinux.o") == 0);
}
void *do_nofail(void *ptr, const char *expr)
{
if (!ptr)
fatal("modpost: Memory allocation failure: %s.\n", expr);
return ptr;
}
/* A list of all modules we processed */
static struct module *modules;
static struct module *find_module(char *modname)
{
struct module *mod;
for (mod = modules; mod; mod = mod->next)
if (strcmp(mod->name, modname) == 0)
break;
return mod;
}
static struct module *new_module(char *modname)
{
struct module *mod;
char *p, *s;
mod = NOFAIL(malloc(sizeof(*mod)));
memset(mod, 0, sizeof(*mod));
p = NOFAIL(strdup(modname));
/* strip trailing .o */
s = strrchr(p, '.');
if (s != NULL)
if (strcmp(s, ".o") == 0) {
*s = '\0';
mod->is_dot_o = 1;
}
/* add to list */
mod->name = p;
mod->gpl_compatible = -1;
mod->next = modules;
modules = mod;
return mod;
}
/* A hash of all exported symbols,
* struct symbol is also used for lists of unresolved symbols */
#define SYMBOL_HASH_SIZE 1024
struct symbol {
struct symbol *next;
struct module *module;
unsigned int crc;
int crc_valid;
unsigned int weak:1;
unsigned int vmlinux:1; /* 1 if symbol is defined in vmlinux */
unsigned int kernel:1; /* 1 if symbol is from kernel
* (only for external modules) **/
unsigned int preloaded:1; /* 1 if symbol from Module.symvers */
enum export export; /* Type of export */
char name[0];
};
static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
/* This is based on the hash agorithm from gdbm, via tdb */
static inline unsigned int tdb_hash(const char *name)
{
unsigned value; /* Used to compute the hash value. */
unsigned i; /* Used to cycle through random values. */
/* Set the initial value from the key size. */
for (value = 0x238F13AF * strlen(name), i = 0; name[i]; i++)
value = (value + (((unsigned char *)name)[i] << (i*5 % 24)));
return (1103515243 * value + 12345);
}
/**
* Allocate a new symbols for use in the hash of exported symbols or
* the list of unresolved symbols per module
**/
static struct symbol *alloc_symbol(const char *name, unsigned int weak,
struct symbol *next)
{
struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
memset(s, 0, sizeof(*s));
strcpy(s->name, name);
s->weak = weak;
s->next = next;
return s;
}
/* For the hash of exported symbols */
static struct symbol *new_symbol(const char *name, struct module *module,
enum export export)
{
unsigned int hash;
struct symbol *new;
hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
new->module = module;
new->export = export;
return new;
}
static struct symbol *find_symbol(const char *name)
{
struct symbol *s;
/* For our purposes, .foo matches foo. PPC64 needs this. */
if (name[0] == '.')
name++;
for (s = symbolhash[tdb_hash(name) % SYMBOL_HASH_SIZE]; s; s = s->next) {
if (strcmp(s->name, name) == 0)
return s;
}
return NULL;
}
static struct {
const char *str;
enum export export;
} export_list[] = {
{ .str = "EXPORT_SYMBOL", .export = export_plain },
{ .str = "EXPORT_UNUSED_SYMBOL", .export = export_unused },
{ .str = "EXPORT_SYMBOL_GPL", .export = export_gpl },
{ .str = "EXPORT_UNUSED_SYMBOL_GPL", .export = export_unused_gpl },
{ .str = "EXPORT_SYMBOL_GPL_FUTURE", .export = export_gpl_future },
{ .str = "(unknown)", .export = export_unknown },
};
static const char *export_str(enum export ex)
{
return export_list[ex].str;
}
static enum export export_no(const char *s)
{
int i;
if (!s)
return export_unknown;
for (i = 0; export_list[i].export != export_unknown; i++) {
if (strcmp(export_list[i].str, s) == 0)
return export_list[i].export;
}
return export_unknown;
}
static const char *sec_name(struct elf_info *elf, int secindex);
#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
{
const char *secname = sec_name(elf, sec);
if (strstarts(secname, "___ksymtab+"))
return export_plain;
else if (strstarts(secname, "___ksymtab_unused+"))
return export_unused;
else if (strstarts(secname, "___ksymtab_gpl+"))
return export_gpl;
else if (strstarts(secname, "___ksymtab_unused_gpl+"))
return export_unused_gpl;
else if (strstarts(secname, "___ksymtab_gpl_future+"))
return export_gpl_future;
else
return export_unknown;
}
static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
{
if (sec == elf->export_sec)
return export_plain;
else if (sec == elf->export_unused_sec)
return export_unused;
else if (sec == elf->export_gpl_sec)
return export_gpl;
else if (sec == elf->export_unused_gpl_sec)
return export_unused_gpl;
else if (sec == elf->export_gpl_future_sec)
return export_gpl_future;
else
return export_unknown;
}
/**
* Add an exported symbol - it may have already been added without a
* CRC, in this case just update the CRC
**/
static struct symbol *sym_add_exported(const char *name, struct module *mod,
enum export export)
{
struct symbol *s = find_symbol(name);
if (!s) {
s = new_symbol(name, mod, export);
} else {
if (!s->preloaded) {
warn("%s: '%s' exported twice. Previous export "
"was in %s%s\n", mod->name, name,
s->module->name,
is_vmlinux(s->module->name) ?"":".ko");
} else {
/* In case Modules.symvers was out of date */
s->module = mod;
}
}
s->preloaded = 0;
s->vmlinux = is_vmlinux(mod->name);
s->kernel = 0;
s->export = export;
return s;
}
static void sym_update_crc(const char *name, struct module *mod,
unsigned int crc, enum export export)
{
struct symbol *s = find_symbol(name);
if (!s)
s = new_symbol(name, mod, export);
s->crc = crc;
s->crc_valid = 1;
}
void *grab_file(const char *filename, unsigned long *size)
{
struct stat st;
void *map = MAP_FAILED;
int fd;
fd = open(filename, O_RDONLY);
if (fd < 0)
return NULL;
if (fstat(fd, &st))
goto failed;
*size = st.st_size;
map = mmap(NULL, *size, PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
failed:
close(fd);
if (map == MAP_FAILED)
return NULL;
return map;
}
/**
* Return a copy of the next line in a mmap'ed file.
* spaces in the beginning of the line is trimmed away.
* Return a pointer to a static buffer.
**/
char *get_next_line(unsigned long *pos, void *file, unsigned long size)
{
static char line[4096];
int skip = 1;
size_t len = 0;
signed char *p = (signed char *)file + *pos;
char *s = line;
for (; *pos < size ; (*pos)++) {
if (skip && isspace(*p)) {
p++;
continue;
}
skip = 0;
if (*p != '\n' && (*pos < size)) {
len++;
*s++ = *p++;
if (len > 4095)
break; /* Too long, stop */
} else {
/* End of string */
*s = '\0';
return line;
}
}
/* End of buffer */
return NULL;
}
void release_file(void *file, unsigned long size)
{
munmap(file, size);
}
static int parse_elf(struct elf_info *info, const char *filename)
{
unsigned int i;
Elf_Ehdr *hdr;
Elf_Shdr *sechdrs;
Elf_Sym *sym;
const char *secstrings;
unsigned int symtab_idx = ~0U, symtab_shndx_idx = ~0U;
hdr = grab_file(filename, &info->size);
if (!hdr) {
perror(filename);
exit(1);
}
info->hdr = hdr;
if (info->size < sizeof(*hdr)) {
/* file too small, assume this is an empty .o file */
return 0;
}
/* Is this a valid ELF file? */
if ((hdr->e_ident[EI_MAG0] != ELFMAG0) ||
(hdr->e_ident[EI_MAG1] != ELFMAG1) ||
(hdr->e_ident[EI_MAG2] != ELFMAG2) ||
(hdr->e_ident[EI_MAG3] != ELFMAG3)) {
/* Not an ELF file - silently ignore it */
return 0;
}
/* Fix endianness in ELF header */
hdr->e_type = TO_NATIVE(hdr->e_type);
hdr->e_machine = TO_NATIVE(hdr->e_machine);
hdr->e_version = TO_NATIVE(hdr->e_version);
hdr->e_entry = TO_NATIVE(hdr->e_entry);
hdr->e_phoff = TO_NATIVE(hdr->e_phoff);
hdr->e_shoff = TO_NATIVE(hdr->e_shoff);
hdr->e_flags = TO_NATIVE(hdr->e_flags);
hdr->e_ehsize = TO_NATIVE(hdr->e_ehsize);
hdr->e_phentsize = TO_NATIVE(hdr->e_phentsize);
hdr->e_phnum = TO_NATIVE(hdr->e_phnum);
hdr->e_shentsize = TO_NATIVE(hdr->e_shentsize);
hdr->e_shnum = TO_NATIVE(hdr->e_shnum);
hdr->e_shstrndx = TO_NATIVE(hdr->e_shstrndx);
sechdrs = (void *)hdr + hdr->e_shoff;
info->sechdrs = sechdrs;
/* Check if file offset is correct */
if (hdr->e_shoff > info->size) {
fatal("section header offset=%lu in file '%s' is bigger than "
"filesize=%lu\n", (unsigned long)hdr->e_shoff,
filename, info->size);
return 0;
}
if (hdr->e_shnum == SHN_UNDEF) {
/*
* There are more than 64k sections,
* read count from .sh_size.
*/
info->num_sections = TO_NATIVE(sechdrs[0].sh_size);
}
else {
info->num_sections = hdr->e_shnum;
}
if (hdr->e_shstrndx == SHN_XINDEX) {
info->secindex_strings = TO_NATIVE(sechdrs[0].sh_link);
}
else {
info->secindex_strings = hdr->e_shstrndx;
}
/* Fix endianness in section headers */
for (i = 0; i < info->num_sections; i++) {
sechdrs[i].sh_name = TO_NATIVE(sechdrs[i].sh_name);
sechdrs[i].sh_type = TO_NATIVE(sechdrs[i].sh_type);
sechdrs[i].sh_flags = TO_NATIVE(sechdrs[i].sh_flags);
sechdrs[i].sh_addr = TO_NATIVE(sechdrs[i].sh_addr);
sechdrs[i].sh_offset = TO_NATIVE(sechdrs[i].sh_offset);
sechdrs[i].sh_size = TO_NATIVE(sechdrs[i].sh_size);
sechdrs[i].sh_link = TO_NATIVE(sechdrs[i].sh_link);
sechdrs[i].sh_info = TO_NATIVE(sechdrs[i].sh_info);
sechdrs[i].sh_addralign = TO_NATIVE(sechdrs[i].sh_addralign);
sechdrs[i].sh_entsize = TO_NATIVE(sechdrs[i].sh_entsize);
}
/* Find symbol table. */
secstrings = (void *)hdr + sechdrs[info->secindex_strings].sh_offset;
for (i = 1; i < info->num_sections; i++) {
const char *secname;
int nobits = sechdrs[i].sh_type == SHT_NOBITS;
if (!nobits && sechdrs[i].sh_offset > info->size) {
fatal("%s is truncated. sechdrs[i].sh_offset=%lu > "
"sizeof(*hrd)=%zu\n", filename,
(unsigned long)sechdrs[i].sh_offset,
sizeof(*hdr));
return 0;
}
secname = secstrings + sechdrs[i].sh_name;
if (strcmp(secname, ".modinfo") == 0) {
if (nobits)
fatal("%s has NOBITS .modinfo\n", filename);
info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
info->modinfo_len = sechdrs[i].sh_size;
} else if (strcmp(secname, "__ksymtab") == 0)
info->export_sec = i;
else if (strcmp(secname, "__ksymtab_unused") == 0)
info->export_unused_sec = i;
else if (strcmp(secname, "__ksymtab_gpl") == 0)
info->export_gpl_sec = i;
else if (strcmp(secname, "__ksymtab_unused_gpl") == 0)
info->export_unused_gpl_sec = i;
else if (strcmp(secname, "__ksymtab_gpl_future") == 0)
info->export_gpl_future_sec = i;
if (sechdrs[i].sh_type == SHT_SYMTAB) {
unsigned int sh_link_idx;
symtab_idx = i;
info->symtab_start = (void *)hdr +
sechdrs[i].sh_offset;
info->symtab_stop = (void *)hdr +
sechdrs[i].sh_offset + sechdrs[i].sh_size;
sh_link_idx = sechdrs[i].sh_link;
info->strtab = (void *)hdr +
sechdrs[sh_link_idx].sh_offset;
}
/* 32bit section no. table? ("more than 64k sections") */
if (sechdrs[i].sh_type == SHT_SYMTAB_SHNDX) {
symtab_shndx_idx = i;
info->symtab_shndx_start = (void *)hdr +
sechdrs[i].sh_offset;
info->symtab_shndx_stop = (void *)hdr +
sechdrs[i].sh_offset + sechdrs[i].sh_size;
}
}
if (!info->symtab_start)
fatal("%s has no symtab?\n", filename);
/* Fix endianness in symbols */
for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
sym->st_shndx = TO_NATIVE(sym->st_shndx);
sym->st_name = TO_NATIVE(sym->st_name);
sym->st_value = TO_NATIVE(sym->st_value);
sym->st_size = TO_NATIVE(sym->st_size);
}
if (symtab_shndx_idx != ~0U) {
Elf32_Word *p;
if (symtab_idx != sechdrs[symtab_shndx_idx].sh_link)
fatal("%s: SYMTAB_SHNDX has bad sh_link: %u!=%u\n",
filename, sechdrs[symtab_shndx_idx].sh_link,
symtab_idx);
/* Fix endianness */
for (p = info->symtab_shndx_start; p < info->symtab_shndx_stop;
p++)
*p = TO_NATIVE(*p);
}
return 1;
}
static void parse_elf_finish(struct elf_info *info)
{
release_file(info->hdr, info->size);
}
static int ignore_undef_symbol(struct elf_info *info, const char *symname)
{
/* ignore __this_module, it will be resolved shortly */
if (strcmp(symname, MODULE_SYMBOL_PREFIX "__this_module") == 0)
return 1;
/* ignore global offset table */
if (strcmp(symname, "_GLOBAL_OFFSET_TABLE_") == 0)
return 1;
if (info->hdr->e_machine == EM_PPC)
/* Special register function linked on all modules during final link of .ko */
if (strncmp(symname, "_restgpr_", sizeof("_restgpr_") - 1) == 0 ||
strncmp(symname, "_savegpr_", sizeof("_savegpr_") - 1) == 0 ||
strncmp(symname, "_rest32gpr_", sizeof("_rest32gpr_") - 1) == 0 ||
strncmp(symname, "_save32gpr_", sizeof("_save32gpr_") - 1) == 0)
return 1;
if (info->hdr->e_machine == EM_PPC64)
/* Special register function linked on all modules during final link of .ko */
if (strncmp(symname, "_restgpr0_", sizeof("_restgpr0_") - 1) == 0 ||
strncmp(symname, "_savegpr0_", sizeof("_savegpr0_") - 1) == 0)
return 1;
/* Do not ignore this symbol */
return 0;
}
#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
static void handle_modversions(struct module *mod, struct elf_info *info,
Elf_Sym *sym, const char *symname)
{
unsigned int crc;
enum export export;
if ((!is_vmlinux(mod->name) || mod->is_dot_o) &&
strncmp(symname, "__ksymtab", 9) == 0)
export = export_from_secname(info, get_secindex(info, sym));
else
export = export_from_sec(info, get_secindex(info, sym));
switch (sym->st_shndx) {
case SHN_COMMON:
warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
break;
case SHN_ABS:
/* CRC'd symbol */
if (strncmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
crc = (unsigned int) sym->st_value;
sym_update_crc(symname + strlen(CRC_PFX), mod, crc,
export);
}
break;
case SHN_UNDEF:
/* undefined symbol */
if (ELF_ST_BIND(sym->st_info) != STB_GLOBAL &&
ELF_ST_BIND(sym->st_info) != STB_WEAK)
break;
if (ignore_undef_symbol(info, symname))
break;
/* cope with newer glibc (2.3.4 or higher) STT_ definition in elf.h */
#if defined(STT_REGISTER) || defined(STT_SPARC_REGISTER)
/* add compatibility with older glibc */
#ifndef STT_SPARC_REGISTER
#define STT_SPARC_REGISTER STT_REGISTER
#endif
if (info->hdr->e_machine == EM_SPARC ||
info->hdr->e_machine == EM_SPARCV9) {
/* Ignore register directives. */
if (ELF_ST_TYPE(sym->st_info) == STT_SPARC_REGISTER)
break;
if (symname[0] == '.') {
char *munged = strdup(symname);
munged[0] = '_';
munged[1] = toupper(munged[1]);
symname = munged;
}
}
#endif
if (memcmp(symname, MODULE_SYMBOL_PREFIX,
strlen(MODULE_SYMBOL_PREFIX)) == 0) {
mod->unres =
alloc_symbol(symname +
strlen(MODULE_SYMBOL_PREFIX),
ELF_ST_BIND(sym->st_info) == STB_WEAK,
mod->unres);
}
break;
default:
/* All exported symbols */
if (strncmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
sym_add_exported(symname + strlen(KSYMTAB_PFX), mod,
export);
}
if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
mod->has_init = 1;
if (strcmp(symname, MODULE_SYMBOL_PREFIX "cleanup_module") == 0)
mod->has_cleanup = 1;
break;
}
}
/**
* Parse tag=value strings from .modinfo section
**/
static char *next_string(char *string, unsigned long *secsize)
{
/* Skip non-zero chars */
while (string[0]) {
string++;
if ((*secsize)-- <= 1)
return NULL;
}
/* Skip any zero padding. */
while (!string[0]) {
string++;
if ((*secsize)-- <= 1)
return NULL;
}
return string;
}
static char *get_next_modinfo(void *modinfo, unsigned long modinfo_len,
const char *tag, char *info)
{
char *p;
unsigned int taglen = strlen(tag);
unsigned long size = modinfo_len;
if (info) {
size -= info - (char *)modinfo;
modinfo = next_string(info, &size);
}
for (p = modinfo; p; p = next_string(p, &size)) {
if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
return p + taglen + 1;
}
return NULL;
}
static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
const char *tag)
{
return get_next_modinfo(modinfo, modinfo_len, tag, NULL);
}
/**
* Test if string s ends in string sub
* return 0 if match
**/
static int strrcmp(const char *s, const char *sub)
{
int slen, sublen;
if (!s || !sub)
return 1;
slen = strlen(s);
sublen = strlen(sub);
if ((slen == 0) || (sublen == 0))
return 1;
if (sublen > slen)
return 1;
return memcmp(s + slen - sublen, sub, sublen);
}
static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
{
if (sym)
return elf->strtab + sym->st_name;
else
return "(unknown)";
}
static const char *sec_name(struct elf_info *elf, int secindex)
{
Elf_Shdr *sechdrs = elf->sechdrs;
return (void *)elf->hdr +
elf->sechdrs[elf->secindex_strings].sh_offset +
sechdrs[secindex].sh_name;
}
static const char *sech_name(struct elf_info *elf, Elf_Shdr *sechdr)
{
return (void *)elf->hdr +
elf->sechdrs[elf->secindex_strings].sh_offset +
sechdr->sh_name;
}
/* if sym is empty or point to a string
* like ".[0-9]+" then return 1.
* This is the optional prefix added by ld to some sections
*/
static int number_prefix(const char *sym)
{
if (*sym++ == '\0')
return 1;
if (*sym != '.')
return 0;
do {
char c = *sym++;
if (c < '0' || c > '9')
return 0;
} while (*sym);
return 1;
}
/* The pattern is an array of simple patterns.
* "foo" will match an exact string equal to "foo"
* "*foo" will match a string that ends with "foo"
* "foo*" will match a string that begins with "foo"
* "foo$" will match a string equal to "foo" or "foo.1"
* where the '1' can be any number including several digits.
* The $ syntax is for sections where ld append a dot number
* to make section name unique.
*/
static int match(const char *sym, const char * const pat[])
{
const char *p;
while (*pat) {
p = *pat++;
const char *endp = p + strlen(p) - 1;
/* "*foo" */
if (*p == '*') {
if (strrcmp(sym, p + 1) == 0)
return 1;
}
/* "foo*" */
else if (*endp == '*') {
if (strncmp(sym, p, strlen(p) - 1) == 0)
return 1;
}
/* "foo$" */
else if (*endp == '$') {
if (strncmp(sym, p, strlen(p) - 1) == 0) {
if (number_prefix(sym + strlen(p) - 1))
return 1;
}
}
/* no wildcards */
else {
if (strcmp(p, sym) == 0)
return 1;
}
}
/* no match */
return 0;
}
/* sections that we do not want to do full section mismatch check on */
static const char *section_white_list[] =
{
".comment*",
".debug*",
".zdebug*", /* Compressed debug sections. */
".GCC-command-line", /* mn10300 */
".GCC.command.line", /* record-gcc-switches, non mn10300 */
".mdebug*", /* alpha, score, mips etc. */
".pdr", /* alpha, score, mips etc. */
".stab*",
".note*",
".got*",
".toc*",
".xt.prop", /* xtensa */
".xt.lit", /* xtensa */
".arcextmap*", /* arc */
".gnu.linkonce.arcext*", /* arc : modules */
NULL
};
/*
* This is used to find sections missing the SHF_ALLOC flag.
* The cause of this is often a section specified in assembler
* without "ax" / "aw".
*/
static void check_section(const char *modname, struct elf_info *elf,
Elf_Shdr *sechdr)
{
const char *sec = sech_name(elf, sechdr);
if (sechdr->sh_type == SHT_PROGBITS &&
!(sechdr->sh_flags & SHF_ALLOC) &&
!match(sec, section_white_list)) {
warn("%s (%s): unexpected non-allocatable section.\n"
"Did you forget to use \"ax\"/\"aw\" in a .S file?\n"
"Note that for example <linux/init.h> contains\n"
"section definitions for use in .S files.\n\n",
modname, sec);
}
}
#define ALL_INIT_DATA_SECTIONS \
".init.setup$", ".init.rodata$", \
".cpuinit.rodata$", ".meminit.rodata$", \
".init.data$", ".cpuinit.data$", ".meminit.data$"
#define ALL_EXIT_DATA_SECTIONS \
".exit.data$", ".cpuexit.data$", ".memexit.data$"
#define ALL_INIT_TEXT_SECTIONS \
".init.text$", ".cpuinit.text$", ".meminit.text$"
#define ALL_EXIT_TEXT_SECTIONS \
".exit.text$", ".cpuexit.text$", ".memexit.text$"
#define ALL_PCI_INIT_SECTIONS \
".pci_fixup_early$", ".pci_fixup_header$", ".pci_fixup_final$", \
".pci_fixup_enable$", ".pci_fixup_resume$", \
".pci_fixup_resume_early$", ".pci_fixup_suspend$"
#define ALL_XXXINIT_SECTIONS CPU_INIT_SECTIONS, MEM_INIT_SECTIONS
#define ALL_XXXEXIT_SECTIONS CPU_EXIT_SECTIONS, MEM_EXIT_SECTIONS
#define ALL_INIT_SECTIONS INIT_SECTIONS, ALL_XXXINIT_SECTIONS
#define ALL_EXIT_SECTIONS EXIT_SECTIONS, ALL_XXXEXIT_SECTIONS
#define DATA_SECTIONS ".data$", ".data.rel$"
#define TEXT_SECTIONS ".text$"
#define INIT_SECTIONS ".init.*"
#define CPU_INIT_SECTIONS ".cpuinit.*"
#define MEM_INIT_SECTIONS ".meminit.*"
#define EXIT_SECTIONS ".exit.*"
#define CPU_EXIT_SECTIONS ".cpuexit.*"
#define MEM_EXIT_SECTIONS ".memexit.*"
/* init data sections */
static const char *init_data_sections[] = { ALL_INIT_DATA_SECTIONS, NULL };
/* all init sections */
static const char *init_sections[] = { ALL_INIT_SECTIONS, NULL };
/* All init and exit sections (code + data) */
static const char *init_exit_sections[] =
{ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS, NULL };
/* data section */
static const char *data_sections[] = { DATA_SECTIONS, NULL };
/* symbols in .data that may refer to init/exit sections */
#define DEFAULT_SYMBOL_WHITE_LIST \
"*driver", \
"*_template", /* scsi uses *_template a lot */ \
"*_timer", /* arm uses ops structures named _timer a lot */ \
"*_sht", /* scsi also used *_sht to some extent */ \
"*_ops", \
"*_probe", \
"*_probe_one", \
"*_console"
static const char *head_sections[] = { ".head.text*", NULL };
static const char *linker_symbols[] =
{ "__init_begin", "_sinittext", "_einittext", NULL };
enum mismatch {
TEXT_TO_ANY_INIT,
DATA_TO_ANY_INIT,
TEXT_TO_ANY_EXIT,
DATA_TO_ANY_EXIT,
XXXINIT_TO_SOME_INIT,
XXXEXIT_TO_SOME_EXIT,
ANY_INIT_TO_ANY_EXIT,
ANY_EXIT_TO_ANY_INIT,
EXPORT_TO_INIT_EXIT,
};
struct sectioncheck {
const char *fromsec[20];
const char *tosec[20];
enum mismatch mismatch;
const char *symbol_white_list[20];
};
const struct sectioncheck sectioncheck[] = {
/* Do not reference init/exit code/data from
* normal code and data
*/
{
.fromsec = { TEXT_SECTIONS, NULL },
.tosec = { ALL_INIT_SECTIONS, NULL },
.mismatch = TEXT_TO_ANY_INIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.tosec = { ALL_XXXINIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_INIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.tosec = { INIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_INIT,
.symbol_white_list = {
"*_template", "*_timer", "*_sht", "*_ops",
"*_probe", "*_probe_one", "*_console", NULL
},
},
{
.fromsec = { TEXT_SECTIONS, NULL },
.tosec = { ALL_EXIT_SECTIONS, NULL },
.mismatch = TEXT_TO_ANY_EXIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
{
.fromsec = { DATA_SECTIONS, NULL },
.tosec = { ALL_EXIT_SECTIONS, NULL },
.mismatch = DATA_TO_ANY_EXIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not reference init code/data from cpuinit/meminit code/data */
{
.fromsec = { ALL_XXXINIT_SECTIONS, NULL },
.tosec = { INIT_SECTIONS, NULL },
.mismatch = XXXINIT_TO_SOME_INIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not reference cpuinit code/data from meminit code/data */
{
.fromsec = { MEM_INIT_SECTIONS, NULL },
.tosec = { CPU_INIT_SECTIONS, NULL },
.mismatch = XXXINIT_TO_SOME_INIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},
/* Do not reference meminit code/data from cpuinit code/data */
{
.fromsec = { CPU_INIT_SECTIONS, NULL },
.tosec = { MEM_INIT_SECTIONS, NULL },
.mismatch = XXXINIT_TO_SOME_INIT,
.symbol_white_list = { DEFAULT_SYMBOL_WHITE_LIST, NULL },
},