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authorLinus Torvalds <torvalds@g5.osdl.org>2006-03-25 08:48:48 -0800
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-25 08:48:48 -0800
commit2e1ca21d46aaef95101723fa402f39d3a95aba59 (patch)
treecd95efefb9ccb6ab4ac0589d01c06cdfc22cc989 /scripts/mod/modpost.c
parent315ab19a6d12d6af7b6957090822f3057ab7e80f (diff)
parenteae0f536f640bb95f2ad437a57c40c7d5683d1ac (diff)
Merge master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild
* master.kernel.org:/pub/scm/linux/kernel/git/sam/kbuild: (46 commits) kbuild: remove obsoleted scripts/reference_* files kbuild: fix make help & make *pkg kconfig: fix time ordering of writes to .kconfig.d and include/linux/autoconf.h Kconfig: remove the CONFIG_CC_ALIGN_* options kbuild: add -fverbose-asm to i386 Makefile kbuild: clean-up genksyms kbuild: Lindent genksyms.c kbuild: fix genksyms build error kbuild: in makefile.txt note that Makefile is preferred name for kbuild files kbuild: replace PHONY with FORCE kbuild: Fix bug in crc symbol generating of kernel and modules kbuild: change kbuild to not rely on incorrect GNU make behavior kbuild: when warning symbols exported twice now tell user this is the problem kbuild: fix make dir/file.xx when asm symlink is missing kbuild: in the section mismatch check try harder to find symbols kbuild: fix section mismatch check for unwind on IA64 kbuild: kill false positives from section mismatch warnings for powerpc kbuild: kill trailing whitespace in modpost & friends kbuild: small update of allnoconfig description kbuild: make namespace.pl CROSS_COMPILE happy ... Trivial conflict in arch/ppc/boot/Makefile manually fixed up
Diffstat (limited to 'scripts/mod/modpost.c')
-rw-r--r--scripts/mod/modpost.c698
1 files changed, 562 insertions, 136 deletions
diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index b8b2a560b26..0b92ddff26f 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -2,7 +2,7 @@
*
* Copyright 2003 Kai Germaschewski
* Copyright 2002-2004 Rusty Russell, IBM Corporation
- *
+ * Copyright 2006 Sam Ravnborg
* Based in part on module-init-tools/depmod.c,file2alias
*
* This software may be used and distributed according to the terms
@@ -20,9 +20,10 @@ int modversions = 0;
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;
-void
-fatal(const char *fmt, ...)
+void fatal(const char *fmt, ...)
{
va_list arglist;
@@ -35,8 +36,7 @@ fatal(const char *fmt, ...)
exit(1);
}
-void
-warn(const char *fmt, ...)
+void warn(const char *fmt, ...)
{
va_list arglist;
@@ -47,6 +47,18 @@ warn(const char *fmt, ...)
va_end(arglist);
}
+static int is_vmlinux(const char *modname)
+{
+ const char *myname;
+
+ if ((myname = strrchr(modname, '/')))
+ myname++;
+ else
+ myname = modname;
+
+ return strcmp(myname, "vmlinux") == 0;
+}
+
void *do_nofail(void *ptr, const char *expr)
{
if (!ptr) {
@@ -59,8 +71,7 @@ void *do_nofail(void *ptr, const char *expr)
static struct module *modules;
-struct module *
-find_module(char *modname)
+static struct module *find_module(char *modname)
{
struct module *mod;
@@ -70,12 +81,11 @@ find_module(char *modname)
return mod;
}
-struct module *
-new_module(char *modname)
+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));
@@ -104,6 +114,10 @@ struct symbol {
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 */
char name[0];
};
@@ -122,11 +136,12 @@ static inline unsigned int tdb_hash(const char *name)
return (1103515243 * value + 12345);
}
-/* Allocate a new symbols for use in the hash of exported symbols or
- * the list of unresolved symbols per module */
-
-struct symbol *
-alloc_symbol(const char *name, unsigned int weak, struct symbol *next)
+/**
+ * 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));
@@ -138,9 +153,7 @@ alloc_symbol(const char *name, unsigned int weak, struct symbol *next)
}
/* For the hash of exported symbols */
-
-void
-new_symbol(const char *name, struct module *module, unsigned int *crc)
+static struct symbol *new_symbol(const char *name, struct module *module)
{
unsigned int hash;
struct symbol *new;
@@ -148,14 +161,10 @@ new_symbol(const char *name, struct module *module, unsigned int *crc)
hash = tdb_hash(name) % SYMBOL_HASH_SIZE;
new = symbolhash[hash] = alloc_symbol(name, 0, symbolhash[hash]);
new->module = module;
- if (crc) {
- new->crc = *crc;
- new->crc_valid = 1;
- }
+ return new;
}
-struct symbol *
-find_symbol(const char *name)
+static struct symbol *find_symbol(const char *name)
{
struct symbol *s;
@@ -170,25 +179,42 @@ find_symbol(const char *name)
return NULL;
}
-/* Add an exported symbol - it may have already been added without a
- * CRC, in this case just update the CRC */
-void
-add_exported_symbol(const char *name, struct module *module, unsigned int *crc)
+/**
+ * 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)
{
struct symbol *s = find_symbol(name);
if (!s) {
- new_symbol(name, module, crc);
- return;
- }
- if (crc) {
- s->crc = *crc;
- s->crc_valid = 1;
+ s = new_symbol(name, mod);
+ } 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");
+ }
}
+ s->preloaded = 0;
+ s->vmlinux = is_vmlinux(mod->name);
+ s->kernel = 0;
+ return s;
+}
+
+static void sym_update_crc(const char *name, struct module *mod,
+ unsigned int crc)
+{
+ struct symbol *s = find_symbol(name);
+
+ if (!s)
+ s = new_symbol(name, mod);
+ s->crc = crc;
+ s->crc_valid = 1;
}
-void *
-grab_file(const char *filename, unsigned long *size)
+void *grab_file(const char *filename, unsigned long *size)
{
struct stat st;
void *map;
@@ -207,13 +233,12 @@ grab_file(const char *filename, unsigned long *size)
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)
+/**
+ * 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;
@@ -243,14 +268,12 @@ get_next_line(unsigned long *pos, void *file, unsigned long size)
return NULL;
}
-void
-release_file(void *file, unsigned long size)
+void release_file(void *file, unsigned long size)
{
munmap(file, size);
}
-void
-parse_elf(struct elf_info *info, const char *filename)
+static void parse_elf(struct elf_info *info, const char *filename)
{
unsigned int i;
Elf_Ehdr *hdr = info->hdr;
@@ -297,14 +320,13 @@ parse_elf(struct elf_info *info, const char *filename)
continue;
info->symtab_start = (void *)hdr + sechdrs[i].sh_offset;
- info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
+ info->symtab_stop = (void *)hdr + sechdrs[i].sh_offset
+ sechdrs[i].sh_size;
- info->strtab = (void *)hdr +
+ info->strtab = (void *)hdr +
sechdrs[sechdrs[i].sh_link].sh_offset;
}
if (!info->symtab_start) {
- fprintf(stderr, "modpost: %s no symtab?\n", filename);
- abort();
+ fatal("%s has no symtab?\n", filename);
}
/* Fix endianness in symbols */
for (sym = info->symtab_start; sym < info->symtab_stop; sym++) {
@@ -316,36 +338,31 @@ parse_elf(struct elf_info *info, const char *filename)
return;
truncated:
- fprintf(stderr, "modpost: %s is truncated.\n", filename);
- abort();
+ fatal("%s is truncated.\n", filename);
}
-void
-parse_elf_finish(struct elf_info *info)
+static void parse_elf_finish(struct elf_info *info)
{
release_file(info->hdr, info->size);
}
-#define CRC_PFX "__crc_"
-#define KSYMTAB_PFX "__ksymtab_"
+#define CRC_PFX MODULE_SYMBOL_PREFIX "__crc_"
+#define KSYMTAB_PFX MODULE_SYMBOL_PREFIX "__ksymtab_"
-void
-handle_modversions(struct module *mod, struct elf_info *info,
- Elf_Sym *sym, const char *symname)
+static void handle_modversions(struct module *mod, struct elf_info *info,
+ Elf_Sym *sym, const char *symname)
{
unsigned int crc;
switch (sym->st_shndx) {
case SHN_COMMON:
- fprintf(stderr, "*** Warning: \"%s\" [%s] is COMMON symbol\n",
- symname, mod->name);
+ warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
break;
case SHN_ABS:
/* CRC'd symbol */
if (memcmp(symname, CRC_PFX, strlen(CRC_PFX)) == 0) {
crc = (unsigned int) sym->st_value;
- add_exported_symbol(symname + strlen(CRC_PFX),
- mod, &crc);
+ sym_update_crc(symname + strlen(CRC_PFX), mod, crc);
}
break;
case SHN_UNDEF:
@@ -370,15 +387,15 @@ handle_modversions(struct module *mod, struct elf_info *info,
/* 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;
- }
+ 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 +
@@ -389,8 +406,7 @@ handle_modversions(struct module *mod, struct elf_info *info,
default:
/* All exported symbols */
if (memcmp(symname, KSYMTAB_PFX, strlen(KSYMTAB_PFX)) == 0) {
- add_exported_symbol(symname + strlen(KSYMTAB_PFX),
- mod, NULL);
+ sym_add_exported(symname + strlen(KSYMTAB_PFX), mod);
}
if (strcmp(symname, MODULE_SYMBOL_PREFIX "init_module") == 0)
mod->has_init = 1;
@@ -400,20 +416,9 @@ handle_modversions(struct module *mod, struct elf_info *info,
}
}
-int
-is_vmlinux(const char *modname)
-{
- const char *myname;
-
- if ((myname = strrchr(modname, '/')))
- myname++;
- else
- myname = modname;
-
- return strcmp(myname, "vmlinux") == 0;
-}
-
-/* Parse tag=value strings from .modinfo section */
+/**
+ * Parse tag=value strings from .modinfo section
+ **/
static char *next_string(char *string, unsigned long *secsize)
{
/* Skip non-zero chars */
@@ -446,8 +451,418 @@ static char *get_modinfo(void *modinfo, unsigned long modinfo_len,
return NULL;
}
-void
-read_symbols(char *modname)
+/**
+ * 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);
+}
+
+/**
+ * Whitelist to allow certain references to pass with no warning.
+ * Pattern 1:
+ * If a module parameter is declared __initdata and permissions=0
+ * then this is legal despite the warning generated.
+ * We cannot see value of permissions here, so just ignore
+ * this pattern.
+ * The pattern is identified by:
+ * tosec = .init.data
+ * fromsec = .data*
+ * atsym =__param*
+ *
+ * Pattern 2:
+ * Many drivers utilise a *_driver container with references to
+ * add, remove, probe functions etc.
+ * These functions may often be marked __init and we do not want to
+ * warn here.
+ * the pattern is identified by:
+ * tosec = .init.text | .exit.text
+ * fromsec = .data
+ * atsym = *_driver, *_ops, *_probe, *probe_one
+ **/
+static int secref_whitelist(const char *tosec, const char *fromsec,
+ const char *atsym)
+{
+ int f1 = 1, f2 = 1;
+ const char **s;
+ const char *pat2sym[] = {
+ "_driver",
+ "_ops",
+ "_probe",
+ "_probe_one",
+ NULL
+ };
+
+ /* Check for pattern 1 */
+ if (strcmp(tosec, ".init.data") != 0)
+ f1 = 0;
+ if (strncmp(fromsec, ".data", strlen(".data")) != 0)
+ f1 = 0;
+ if (strncmp(atsym, "__param", strlen("__param")) != 0)
+ f1 = 0;
+
+ if (f1)
+ return f1;
+
+ /* Check for pattern 2 */
+ if ((strcmp(tosec, ".init.text") != 0) &&
+ (strcmp(tosec, ".exit.text") != 0))
+ f2 = 0;
+ if (strcmp(fromsec, ".data") != 0)
+ f2 = 0;
+
+ for (s = pat2sym; *s; s++)
+ if (strrcmp(atsym, *s) == 0)
+ f1 = 1;
+
+ return f1 && f2;
+}
+
+/**
+ * Find symbol based on relocation record info.
+ * In some cases the symbol supplied is a valid symbol so
+ * return refsym. If st_name != 0 we assume this is a valid symbol.
+ * In other cases the symbol needs to be looked up in the symbol table
+ * based on section and address.
+ * **/
+static Elf_Sym *find_elf_symbol(struct elf_info *elf, Elf_Addr addr,
+ Elf_Sym *relsym)
+{
+ Elf_Sym *sym;
+
+ if (relsym->st_name != 0)
+ return relsym;
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ if (sym->st_shndx != relsym->st_shndx)
+ continue;
+ if (sym->st_value == addr)
+ return sym;
+ }
+ return NULL;
+}
+
+/*
+ * Find symbols before or equal addr and after addr - in the section sec.
+ * If we find two symbols with equal offset prefer one with a valid name.
+ * The ELF format may have a better way to detect what type of symbol
+ * it is, but this works for now.
+ **/
+static void find_symbols_between(struct elf_info *elf, Elf_Addr addr,
+ const char *sec,
+ Elf_Sym **before, Elf_Sym **after)
+{
+ Elf_Sym *sym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Addr beforediff = ~0;
+ Elf_Addr afterdiff = ~0;
+ const char *secstrings = (void *)hdr +
+ elf->sechdrs[hdr->e_shstrndx].sh_offset;
+
+ *before = NULL;
+ *after = NULL;
+
+ for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+ const char *symsec;
+
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+ symsec = secstrings + elf->sechdrs[sym->st_shndx].sh_name;
+ if (strcmp(symsec, sec) != 0)
+ continue;
+ if (sym->st_value <= addr) {
+ if ((addr - sym->st_value) < beforediff) {
+ beforediff = addr - sym->st_value;
+ *before = sym;
+ }
+ else if ((addr - sym->st_value) == beforediff) {
+ /* equal offset, valid name? */
+ const char *name = elf->strtab + sym->st_name;
+ if (name && strlen(name))
+ *before = sym;
+ }
+ }
+ else
+ {
+ if ((sym->st_value - addr) < afterdiff) {
+ afterdiff = sym->st_value - addr;
+ *after = sym;
+ }
+ else if ((sym->st_value - addr) == afterdiff) {
+ /* equal offset, valid name? */
+ const char *name = elf->strtab + sym->st_name;
+ if (name && strlen(name))
+ *after = sym;
+ }
+ }
+ }
+}
+
+/**
+ * Print a warning about a section mismatch.
+ * Try to find symbols near it so user can find it.
+ * Check whitelist before warning - it may be a false positive.
+ **/
+static void warn_sec_mismatch(const char *modname, const char *fromsec,
+ struct elf_info *elf, Elf_Sym *sym, Elf_Rela r)
+{
+ const char *refsymname = "";
+ Elf_Sym *before, *after;
+ Elf_Sym *refsym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ const char *secstrings = (void *)hdr +
+ sechdrs[hdr->e_shstrndx].sh_offset;
+ const char *secname = secstrings + sechdrs[sym->st_shndx].sh_name;
+
+ find_symbols_between(elf, r.r_offset, fromsec, &before, &after);
+
+ refsym = find_elf_symbol(elf, r.r_addend, sym);
+ if (refsym && strlen(elf->strtab + refsym->st_name))
+ refsymname = elf->strtab + refsym->st_name;
+
+ /* check whitelist - we may ignore it */
+ if (before &&
+ secref_whitelist(secname, fromsec, elf->strtab + before->st_name))
+ return;
+
+ if (before && after) {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "between '%s' (at offset 0x%llx) and '%s'\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + before->st_name,
+ (long long)r.r_offset,
+ elf->strtab + after->st_name);
+ } else if (before) {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "after '%s' (at offset 0x%llx)\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + before->st_name,
+ (long long)r.r_offset);
+ } else if (after) {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "before '%s' (at offset -0x%llx)\n",
+ modname, secname, refsymname, fromsec,
+ elf->strtab + before->st_name,
+ (long long)r.r_offset);
+ } else {
+ warn("%s - Section mismatch: reference to %s:%s from %s "
+ "(offset 0x%llx)\n",
+ modname, secname, fromsec, refsymname,
+ (long long)r.r_offset);
+ }
+}
+
+/**
+ * A module includes a number of sections that are discarded
+ * either when loaded or when used as built-in.
+ * For loaded modules all functions marked __init and all data
+ * marked __initdata will be discarded when the module has been intialized.
+ * Likewise for modules used built-in the sections marked __exit
+ * are discarded because __exit marked function are supposed to be called
+ * only when a moduel is unloaded which never happes for built-in modules.
+ * The check_sec_ref() function traverses all relocation records
+ * to find all references to a section that reference a section that will
+ * be discarded and warns about it.
+ **/
+static void check_sec_ref(struct module *mod, const char *modname,
+ struct elf_info *elf,
+ int section(const char*),
+ int section_ref_ok(const char *))
+{
+ int i;
+ Elf_Sym *sym;
+ Elf_Ehdr *hdr = elf->hdr;
+ Elf_Shdr *sechdrs = elf->sechdrs;
+ const char *secstrings = (void *)hdr +
+ sechdrs[hdr->e_shstrndx].sh_offset;
+
+ /* Walk through all sections */
+ for (i = 0; i < hdr->e_shnum; i++) {
+ Elf_Rela *rela;
+ Elf_Rela *start = (void *)hdr + sechdrs[i].sh_offset;
+ Elf_Rela *stop = (void*)start + sechdrs[i].sh_size;
+ const char *name = secstrings + sechdrs[i].sh_name +
+ strlen(".rela");
+ /* We want to process only relocation sections and not .init */
+ if (section_ref_ok(name) || (sechdrs[i].sh_type != SHT_RELA))
+ continue;
+
+ for (rela = start; rela < stop; rela++) {
+ Elf_Rela r;
+ const char *secname;
+ r.r_offset = TO_NATIVE(rela->r_offset);
+ r.r_info = TO_NATIVE(rela->r_info);
+ r.r_addend = TO_NATIVE(rela->r_addend);
+ sym = elf->symtab_start + ELF_R_SYM(r.r_info);
+ /* Skip special sections */
+ if (sym->st_shndx >= SHN_LORESERVE)
+ continue;
+
+ secname = secstrings + sechdrs[sym->st_shndx].sh_name;
+ if (section(secname))
+ warn_sec_mismatch(modname, name, elf, sym, r);
+ }
+ }
+}
+
+/**
+ * Functions used only during module init is marked __init and is stored in
+ * a .init.text section. Likewise data is marked __initdata and stored in
+ * a .init.data section.
+ * If this section is one of these sections return 1
+ * See include/linux/init.h for the details
+ **/
+static int init_section(const char *name)
+{
+ if (strcmp(name, ".init") == 0)
+ return 1;
+ if (strncmp(name, ".init.", strlen(".init.")) == 0)
+ return 1;
+ return 0;
+}
+
+/**
+ * Identify sections from which references to a .init section is OK.
+ *
+ * Unfortunately references to read only data that referenced .init
+ * sections had to be excluded. Almost all of these are false
+ * positives, they are created by gcc. The downside of excluding rodata
+ * is that there really are some user references from rodata to
+ * init code, e.g. drivers/video/vgacon.c:
+ *
+ * const struct consw vga_con = {
+ * con_startup: vgacon_startup,
+ *
+ * where vgacon_startup is __init. If you want to wade through the false
+ * positives, take out the check for rodata.
+ **/
+static int init_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ ".init",
+ ".opd", /* see comment [OPD] at exit_section_ref_ok() */
+ ".toc1", /* used by ppc64 */
+ ".stab",
+ ".rodata",
+ ".text.lock",
+ "__bug_table", /* used by powerpc for BUG() */
+ ".pci_fixup_header",
+ ".pci_fixup_final",
+ ".pdr",
+ "__param",
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".init.",
+ ".altinstructions",
+ ".eh_frame",
+ ".debug",
+ NULL
+ };
+ /* part of section name */
+ const char *namelist3 [] = {
+ ".unwind", /* sample: IA_64.unwind.init.text */
+ NULL
+ };
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ for (s = namelist2; *s; s++)
+ if (strncmp(*s, name, strlen(*s)) == 0)
+ return 1;
+ for (s = namelist3; *s; s++)
+ if (strstr(name, *s) != NULL)
+ return 1;
+ return 0;
+}
+
+/*
+ * Functions used only during module exit is marked __exit and is stored in
+ * a .exit.text section. Likewise data is marked __exitdata and stored in
+ * a .exit.data section.
+ * If this section is one of these sections return 1
+ * See include/linux/init.h for the details
+ **/
+static int exit_section(const char *name)
+{
+ if (strcmp(name, ".exit.text") == 0)
+ return 1;
+ if (strcmp(name, ".exit.data") == 0)
+ return 1;
+ return 0;
+
+}
+
+/*
+ * Identify sections from which references to a .exit section is OK.
+ *
+ * [OPD] Keith Ownes <kaos@sgi.com> commented:
+ * For our future {in}sanity, add a comment that this is the ppc .opd
+ * section, not the ia64 .opd section.
+ * ia64 .opd should not point to discarded sections.
+ **/
+static int exit_section_ref_ok(const char *name)
+{
+ const char **s;
+ /* Absolute section names */
+ const char *namelist1[] = {
+ ".exit.text",
+ ".exit.data",
+ ".init.text",
+ ".opd", /* See comment [OPD] */
+ ".toc1", /* used by ppc64 */
+ ".altinstructions",
+ ".pdr",
+ "__bug_table", /* used by powerpc for BUG() */
+ ".exitcall.exit",
+ ".eh_frame",
+ ".stab",
+ NULL
+ };
+ /* Start of section names */
+ const char *namelist2[] = {
+ ".debug",
+ NULL
+ };
+ /* part of section name */
+ const char *namelist3 [] = {
+ ".unwind", /* Sample: IA_64.unwind.exit.text */
+ NULL
+ };
+
+ for (s = namelist1; *s; s++)
+ if (strcmp(*s, name) == 0)
+ return 1;
+ for (s = namelist2; *s; s++)
+ if (strncmp(*s, name, strlen(*s)) == 0)
+ return 1;
+ for (s = namelist3; *s; s++)
+ if (strstr(name, *s) != NULL)
+ return 1;
+ return 0;
+}
+
+static void read_symbols(char *modname)
{
const char *symname;
char *version;
@@ -462,9 +877,7 @@ read_symbols(char *modname)
/* When there's no vmlinux, don't print warnings about
* unresolved symbols (since there'll be too many ;) */
if (is_vmlinux(modname)) {
- unsigned int fake_crc = 0;
have_vmlinux = 1;
- add_exported_symbol("struct_module", mod, &fake_crc);
mod->skip = 1;
}
@@ -474,6 +887,8 @@ read_symbols(char *modname)
handle_modversions(mod, &info, sym, symname);
handle_moddevtable(mod, &info, sym, symname);
}
+ check_sec_ref(mod, modname, &info, init_section, init_section_ref_ok);
+ check_sec_ref(mod, modname, &info, exit_section, exit_section_ref_ok);
version = get_modinfo(info.modinfo, info.modinfo_len, "version");
if (version)
@@ -499,21 +914,20 @@ read_symbols(char *modname)
* following helper, then compare to the file on disk and
* only update the later if anything changed */
-void __attribute__((format(printf, 2, 3)))
-buf_printf(struct buffer *buf, const char *fmt, ...)
+void __attribute__((format(printf, 2, 3))) buf_printf(struct buffer *buf,
+ const char *fmt, ...)
{
char tmp[SZ];
int len;
va_list ap;
-
+
va_start(ap, fmt);
len = vsnprintf(tmp, SZ, fmt, ap);
buf_write(buf, tmp, len);
va_end(ap);
}
-void
-buf_write(struct buffer *buf, const char *s, int len)
+void buf_write(struct buffer *buf, const char *s, int len)
{
if (buf->size - buf->pos < len) {
buf->size += len + SZ;
@@ -523,10 +937,10 @@ buf_write(struct buffer *buf, const char *s, int len)
buf->pos += len;
}
-/* Header for the generated file */
-
-void
-add_header(struct buffer *b, struct module *mod)
+/**
+ * Header for the generated file
+ **/
+static void add_header(struct buffer *b, struct module *mod)
{
buf_printf(b, "#include <linux/module.h>\n");
buf_printf(b, "#include <linux/vermagic.h>\n");
@@ -546,10 +960,10 @@ add_header(struct buffer *b, struct module *mod)
buf_printf(b, "};\n");
}
-/* Record CRCs for unresolved symbols */
-
-void
-add_versions(struct buffer *b, struct module *mod)
+/**
+ * Record CRCs for unresolved symbols
+ **/
+static void add_versions(struct buffer *b, struct module *mod)
{
struct symbol *s, *exp;
@@ -557,8 +971,8 @@ add_versions(struct buffer *b, struct module *mod)
exp = find_symbol(s->name);
if (!exp || exp->module == mod) {
if (have_vmlinux && !s->weak)
- fprintf(stderr, "*** Warning: \"%s\" [%s.ko] "
- "undefined!\n", s->name, mod->name);
+ warn("\"%s\" [%s.ko] undefined!\n",
+ s->name, mod->name);
continue;
}
s->module = exp->module;
@@ -579,8 +993,7 @@ add_versions(struct buffer *b, struct module *mod)
continue;
}
if (!s->crc_valid) {
- fprintf(stderr, "*** Warning: \"%s\" [%s.ko] "
- "has no CRC!\n",
+ warn("\"%s\" [%s.ko] has no CRC!\n",
s->name, mod->name);
continue;
}
@@ -590,8 +1003,8 @@ add_versions(struct buffer *b, struct module *mod)
buf_printf(b, "};\n");
}
-void
-add_depends(struct buffer *b, struct module *mod, struct module *modules)
+static void add_depends(struct buffer *b, struct module *mod,
+ struct module *modules)
{
struct symbol *s;
struct module *m;
@@ -621,8 +1034,7 @@ add_depends(struct buffer *b, struct module *mod, struct module *modules)
buf_printf(b, "\";\n");
}
-void
-add_srcversion(struct buffer *b, struct module *mod)
+static void add_srcversion(struct buffer *b, struct module *mod)
{
if (mod->srcversion[0]) {
buf_printf(b, "\n");
@@ -631,8 +1043,7 @@ add_srcversion(struct buffer *b, struct module *mod)
}
}
-void
-write_if_changed(struct buffer *b, const char *fname)
+static void write_if_changed(struct buffer *b, const char *fname)
{
char *tmp;
FILE *file;
@@ -676,8 +1087,7 @@ write_if_changed(struct buffer *b, const char *fname)
fclose(file);
}
-void
-read_dump(const char *fname)
+static void read_dump(const char *fname, unsigned int kernel)
{
unsigned long size, pos = 0;
void *file = grab_file(fname, &size);
@@ -691,6 +1101,7 @@ read_dump(const char *fname)
char *symname, *modname, *d;
unsigned int crc;
struct module *mod;
+ struct symbol *s;
if (!(symname = strchr(line, '\t')))
goto fail;
@@ -711,15 +1122,30 @@ read_dump(const char *fname)
mod = new_module(NOFAIL(strdup(modname)));
mod->skip = 1;
}
- add_exported_symbol(symname, mod, &crc);
+ s = sym_add_exported(symname, mod);
+ s->kernel = kernel;
+ s->preloaded = 1;
+ sym_update_crc(symname, mod, crc);
}
return;
fail:
fatal("parse error in symbol dump file\n");
}
-void
-write_dump(const char *fname)
+/* For normal builds always dump all symbols.
+ * For external modules only dump symbols
+ * that are not read from kernel Module.symvers.
+ **/
+static int dump_sym(struct symbol *sym)
+{
+ if (!external_module)
+ return 1;
+ if (sym->vmlinux || sym->kernel)
+ return 0;
+ return 1;
+}
+
+static void write_dump(const char *fname)
{
struct buffer buf = { };
struct symbol *symbol;
@@ -728,34 +1154,33 @@ write_dump(const char *fname)
for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
symbol = symbolhash[n];
while (symbol) {
- symbol = symbol->next;
- }
- }
-
- for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
- symbol = symbolhash[n];
- while (symbol) {
- buf_printf(&buf, "0x%08x\t%s\t%s\n", symbol->crc,
- symbol->name, symbol->module->name);
+ if (dump_sym(symbol))
+ buf_printf(&buf, "0x%08x\t%s\t%s\n",
+ symbol->crc, symbol->name,
+ symbol->module->name);
symbol = symbol->next;
}
}
write_if_changed(&buf, fname);
}
-int
-main(int argc, char **argv)
+int main(int argc, char **argv)
{
struct module *mod;
struct buffer buf = { };
char fname[SZ];
- char *dump_read = NULL, *dump_write = NULL;
+ char *kernel_read = NULL, *module_read = NULL;
+ char *dump_write = NULL;
int opt;
- while ((opt = getopt(argc, argv, "i:mo:a")) != -1) {
+ while ((opt = getopt(argc, argv, "i:I:mo:a")) != -1) {
switch(opt) {
case 'i':
- dump_read = optarg;
+ kernel_read = optarg;
+ break;
+ case 'I':
+ module_read = optarg;
+ external_module = 1;
break;
case 'm':
modversions = 1;
@@ -771,8 +1196,10 @@ main(int argc, char **argv)
}
}
- if (dump_read)
- read_dump(dump_read);
+ if (kernel_read)
+ read_dump(kernel_read, 1);
+ if (module_read)
+ read_dump(module_read, 0);
while (optind < argc) {
read_symbols(argv[optind++]);
@@ -799,4 +1226,3 @@ main(int argc, char **argv)
return 0;
}
-