Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2371 insertions, 0 deletions

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
new file mode 100644
index 000000000..e6be7fc26
--- /dev/null
+++ b/scripts/mod/modpost.c
@@ -0,0 +1,2371 @@
+/* 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 <elf.h>
+#include <fnmatch.h>
+#include <stdio.h>
+#include <ctype.h>
+#include <string.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <errno.h>
+#include "modpost.h"
+#include "../../include/linux/license.h"
+
+/* Are we using CONFIG_MODVERSIONS? */
+static bool modversions;
+/* Is CONFIG_MODULE_SRCVERSION_ALL set? */
+static bool all_versions;
+/* If we are modposting external module set to 1 */
+static bool external_module;
+/* Only warn about unresolved symbols */
+static bool warn_unresolved;
+
+static int sec_mismatch_count;
+static bool sec_mismatch_warn_only = true;
+/* ignore missing files */
+static bool ignore_missing_files;
+/* If set to 1, only warn (instead of error) about missing ns imports */
+static bool allow_missing_ns_imports;
+
+static bool error_occurred;
+
+/*
+ * Cut off the warnings when there are too many. This typically occurs when
+ * vmlinux is missing. ('make modules' without building vmlinux.)
+ */
+#define MAX_UNRESOLVED_REPORTS	10
+static unsigned int nr_unresolved;
+
+/* In kernel, this size is defined in linux/module.h;
+ * here we use Elf_Addr instead of long for covering cross-compile
+ */
+
+#define MODULE_NAME_LEN (64 - sizeof(Elf_Addr))
+
+void __attribute__((format(printf, 2, 3)))
+modpost_log(enum loglevel loglevel, const char *fmt, ...)
+{
+	va_list arglist;
+
+	switch (loglevel) {
+	case LOG_WARN:
+		fprintf(stderr, "WARNING: ");
+		break;
+	case LOG_ERROR:
+		fprintf(stderr, "ERROR: ");
+		break;
+	case LOG_FATAL:
+		fprintf(stderr, "FATAL: ");
+		break;
+	default: /* invalid loglevel, ignore */
+		break;
+	}
+
+	fprintf(stderr, "modpost: ");
+
+	va_start(arglist, fmt);
+	vfprintf(stderr, fmt, arglist);
+	va_end(arglist);
+
+	if (loglevel == LOG_FATAL)
+		exit(1);
+	if (loglevel == LOG_ERROR)
+		error_occurred = true;
+}
+
+static inline bool strends(const char *str, const char *postfix)
+{
+	if (strlen(str) < strlen(postfix))
+		return false;
+
+	return strcmp(str + strlen(str) - strlen(postfix), postfix) == 0;
+}
+
+void *do_nofail(void *ptr, const char *expr)
+{
+	if (!ptr)
+		fatal("Memory allocation failure: %s.\n", expr);
+
+	return ptr;
+}
+
+char *read_text_file(const char *filename)
+{
+	struct stat st;
+	size_t nbytes;
+	int fd;
+	char *buf;
+
+	fd = open(filename, O_RDONLY);
+	if (fd < 0) {
+		perror(filename);
+		exit(1);
+	}
+
+	if (fstat(fd, &st) < 0) {
+		perror(filename);
+		exit(1);
+	}
+
+	buf = NOFAIL(malloc(st.st_size + 1));
+
+	nbytes = st.st_size;
+
+	while (nbytes) {
+		ssize_t bytes_read;
+
+		bytes_read = read(fd, buf, nbytes);
+		if (bytes_read < 0) {
+			perror(filename);
+			exit(1);
+		}
+
+		nbytes -= bytes_read;
+	}
+	buf[st.st_size] = '\0';
+
+	close(fd);
+
+	return buf;
+}
+
+char *get_line(char **stringp)
+{
+	char *orig = *stringp, *next;
+
+	/* do not return the unwanted extra line at EOF */
+	if (!orig || *orig == '\0')
+		return NULL;
+
+	/* don't use strsep here, it is not available everywhere */
+	next = strchr(orig, '\n');
+	if (next)
+		*next++ = '\0';
+
+	*stringp = next;
+
+	return orig;
+}
+
+/* A list of all modules we processed */
+LIST_HEAD(modules);
+
+static struct module *find_module(const char *modname)
+{
+	struct module *mod;
+
+	list_for_each_entry(mod, &modules, list) {
+		if (strcmp(mod->name, modname) == 0)
+			return mod;
+	}
+	return NULL;
+}
+
+static struct module *new_module(const char *name, size_t namelen)
+{
+	struct module *mod;
+
+	mod = NOFAIL(malloc(sizeof(*mod) + namelen + 1));
+	memset(mod, 0, sizeof(*mod));
+
+	INIT_LIST_HEAD(&mod->exported_symbols);
+	INIT_LIST_HEAD(&mod->unresolved_symbols);
+	INIT_LIST_HEAD(&mod->missing_namespaces);
+	INIT_LIST_HEAD(&mod->imported_namespaces);
+
+	memcpy(mod->name, name, namelen);
+	mod->name[namelen] = '\0';
+	mod->is_vmlinux = (strcmp(mod->name, "vmlinux") == 0);
+
+	/*
+	 * Set mod->is_gpl_compatible to true by default. If MODULE_LICENSE()
+	 * is missing, do not check the use for EXPORT_SYMBOL_GPL() becasue
+	 * modpost will exit wiht error anyway.
+	 */
+	mod->is_gpl_compatible = true;
+
+	list_add_tail(&mod->list, &modules);
+
+	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 list_head list;	/* link to module::exported_symbols or module::unresolved_symbols */
+	struct module *module;
+	char *namespace;
+	unsigned int crc;
+	bool crc_valid;
+	bool weak;
+	bool is_gpl_only;	/* exported by EXPORT_SYMBOL_GPL */
+	char name[];
+};
+
+static struct symbol *symbolhash[SYMBOL_HASH_SIZE];
+
+/* This is based on the hash algorithm 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)
+{
+	struct symbol *s = NOFAIL(malloc(sizeof(*s) + strlen(name) + 1));
+
+	memset(s, 0, sizeof(*s));
+	strcpy(s->name, name);
+
+	return s;
+}
+
+/* For the hash of exported symbols */
+static void hash_add_symbol(struct symbol *sym)
+{
+	unsigned int hash;
+
+	hash = tdb_hash(sym->name) % SYMBOL_HASH_SIZE;
+	sym->next = symbolhash[hash];
+	symbolhash[hash] = sym;
+}
+
+static void sym_add_unresolved(const char *name, struct module *mod, bool weak)
+{
+	struct symbol *sym;
+
+	sym = alloc_symbol(name);
+	sym->weak = weak;
+
+	list_add_tail(&sym->list, &mod->unresolved_symbols);
+}
+
+static struct symbol *sym_find_with_module(const char *name, struct module *mod)
+{
+	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 && (!mod || s->module == mod))
+			return s;
+	}
+	return NULL;
+}
+
+static struct symbol *find_symbol(const char *name)
+{
+	return sym_find_with_module(name, NULL);
+}
+
+struct namespace_list {
+	struct list_head list;
+	char namespace[];
+};
+
+static bool contains_namespace(struct list_head *head, const char *namespace)
+{
+	struct namespace_list *list;
+
+	list_for_each_entry(list, head, list) {
+		if (!strcmp(list->namespace, namespace))
+			return true;
+	}
+
+	return false;
+}
+
+static void add_namespace(struct list_head *head, const char *namespace)
+{
+	struct namespace_list *ns_entry;
+
+	if (!contains_namespace(head, namespace)) {
+		ns_entry = NOFAIL(malloc(sizeof(*ns_entry) +
+					 strlen(namespace) + 1));
+		strcpy(ns_entry->namespace, namespace);
+		list_add_tail(&ns_entry->list, head);
+	}
+}
+
+static void *sym_get_data_by_offset(const struct elf_info *info,
+				    unsigned int secindex, unsigned long offset)
+{
+	Elf_Shdr *sechdr = &info->sechdrs[secindex];
+
+	return (void *)info->hdr + sechdr->sh_offset + offset;
+}
+
+void *sym_get_data(const struct elf_info *info, const Elf_Sym *sym)
+{
+	return sym_get_data_by_offset(info, get_secindex(info, sym),
+				      sym->st_value);
+}
+
+static const char *sech_name(const struct elf_info *info, Elf_Shdr *sechdr)
+{
+	return sym_get_data_by_offset(info, info->secindex_strings,
+				      sechdr->sh_name);
+}
+
+static const char *sec_name(const struct elf_info *info, unsigned int secindex)
+{
+	/*
+	 * If sym->st_shndx is a special section index, there is no
+	 * corresponding section header.
+	 * Return "" if the index is out of range of info->sechdrs[] array.
+	 */
+	if (secindex >= info->num_sections)
+		return "";
+
+	return sech_name(info, &info->sechdrs[secindex]);
+}
+
+#define strstarts(str, prefix) (strncmp(str, prefix, strlen(prefix)) == 0)
+
+static void sym_update_namespace(const char *symname, const char *namespace)
+{
+	struct symbol *s = find_symbol(symname);
+
+	/*
+	 * That symbol should have been created earlier and thus this is
+	 * actually an assertion.
+	 */
+	if (!s) {
+		error("Could not update namespace(%s) for symbol %s\n",
+		      namespace, symname);
+		return;
+	}
+
+	free(s->namespace);
+	s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
+}
+
+static struct symbol *sym_add_exported(const char *name, struct module *mod,
+				       bool gpl_only)
+{
+	struct symbol *s = find_symbol(name);
+
+	if (s && (!external_module || s->module->is_vmlinux || s->module == mod)) {
+		error("%s: '%s' exported twice. Previous export was in %s%s\n",
+		      mod->name, name, s->module->name,
+		      s->module->is_vmlinux ? "" : ".ko");
+	}
+
+	s = alloc_symbol(name);
+	s->module = mod;
+	s->is_gpl_only = gpl_only;
+	list_add_tail(&s->list, &mod->exported_symbols);
+	hash_add_symbol(s);
+
+	return s;
+}
+
+static void sym_set_crc(struct symbol *sym, unsigned int crc)
+{
+	sym->crc = crc;
+	sym->crc_valid = true;
+}
+
+static void *grab_file(const char *filename, size_t *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;
+}
+
+static void release_file(void *file, size_t 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) {
+		if (ignore_missing_files) {
+			fprintf(stderr, "%s: %s (ignored)\n", filename,
+				strerror(errno));
+			return 0;
+		}
+		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;
+
+	/* modpost only works for relocatable objects */
+	if (hdr->e_type != ET_REL)
+		fatal("%s: not relocatable object.", filename);
+
+	/* Check if file offset is correct */
+	if (hdr->e_shoff > info->size) {
+		fatal("section header offset=%lu in file '%s' is bigger than filesize=%zu\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;
+		}
+
+		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, "__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 (strstarts(symname, "_restgpr_") ||
+		    strstarts(symname, "_savegpr_") ||
+		    strstarts(symname, "_rest32gpr_") ||
+		    strstarts(symname, "_save32gpr_") ||
+		    strstarts(symname, "_restvr_") ||
+		    strstarts(symname, "_savevr_"))
+			return 1;
+	if (info->hdr->e_machine == EM_PPC64)
+		/* Special register function linked on all modules during final link of .ko */
+		if (strstarts(symname, "_restgpr0_") ||
+		    strstarts(symname, "_savegpr0_") ||
+		    strstarts(symname, "_restvr_") ||
+		    strstarts(symname, "_savevr_") ||
+		    strcmp(symname, ".TOC.") == 0)
+			return 1;
+
+	if (info->hdr->e_machine == EM_S390)
+		/* Expoline thunks are linked on all kernel modules during final link of .ko */
+		if (strstarts(symname, "__s390_indirect_jump_r"))
+			return 1;
+	/* Do not ignore this symbol */
+	return 0;
+}
+
+static void handle_symbol(struct module *mod, struct elf_info *info,
+			  const Elf_Sym *sym, const char *symname)
+{
+	switch (sym->st_shndx) {
+	case SHN_COMMON:
+		if (strstarts(symname, "__gnu_lto_")) {
+			/* Should warn here, but modpost runs before the linker */
+		} else
+			warn("\"%s\" [%s] is COMMON symbol\n", symname, mod->name);
+		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;
+		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 = NOFAIL(strdup(symname));
+				munged[0] = '_';
+				munged[1] = toupper(munged[1]);
+				symname = munged;
+			}
+		}
+
+		sym_add_unresolved(symname, mod,
+				   ELF_ST_BIND(sym->st_info) == STB_WEAK);
+		break;
+	default:
+		/* All exported symbols */
+		if (strstarts(symname, "__ksymtab_")) {
+			const char *name, *secname;
+
+			name = symname + strlen("__ksymtab_");
+			secname = sec_name(info, get_secindex(info, sym));
+
+			if (strstarts(secname, "___ksymtab_gpl+"))
+				sym_add_exported(name, mod, true);
+			else if (strstarts(secname, "___ksymtab+"))
+				sym_add_exported(name, mod, false);
+		}
+		if (strcmp(symname, "init_module") == 0)
+			mod->has_init = true;
+		if (strcmp(symname, "cleanup_module") == 0)
+			mod->has_cleanup = true;
+		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(struct elf_info *info, const char *tag,
+			      char *prev)
+{
+	char *p;
+	unsigned int taglen = strlen(tag);
+	char *modinfo = info->modinfo;
+	unsigned long size = info->modinfo_len;
+
+	if (prev) {
+		size -= prev - modinfo;
+		modinfo = next_string(prev, &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(struct elf_info *info, const char *tag)
+
+{
+	return get_next_modinfo(info, tag, NULL);
+}
+
+static const char *sym_name(struct elf_info *elf, Elf_Sym *sym)
+{
+	if (sym)
+		return elf->strtab + sym->st_name;
+	else
+		return "(unknown)";
+}
+
+/*
+ * Check whether the 'string' argument matches one of the 'patterns',
+ * an array of shell wildcard patterns (glob).
+ *
+ * Return true is there is a match.
+ */
+static bool match(const char *string, const char *const patterns[])
+{
+	const char *pattern;
+
+	while ((pattern = *patterns++)) {
+		if (!fnmatch(pattern, string, 0))
+			return true;
+	}
+
+	return false;
+}
+
+/* useful to pass patterns to match() directly */
+#define PATTERNS(...) \
+	({ \
+		static const char *const patterns[] = {__VA_ARGS__, NULL}; \
+		patterns; \
+	})
+
+/* sections that we do not want to do full section mismatch check on */
+static const char *const section_white_list[] =
+{
+	".comment*",
+	".debug*",
+	".zdebug*",		/* Compressed debug sections. */
+	".GCC.command.line",	/* record-gcc-switches */
+	".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 */
+	".cmem*",			/* EZchip */
+	".fmt_slot*",			/* EZchip */
+	".gnu.lto*",
+	".discard.*",
+	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", ".meminit.rodata", \
+	".init.data", ".meminit.data"
+#define ALL_EXIT_DATA_SECTIONS \
+	".exit.data", ".memexit.data"
+
+#define ALL_INIT_TEXT_SECTIONS \
+	".init.text", ".meminit.text"
+#define ALL_EXIT_TEXT_SECTIONS \
+	".exit.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 MEM_INIT_SECTIONS
+#define ALL_XXXEXIT_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", ".text.unlikely", ".sched.text", \
+		".kprobes.text", ".cpuidle.text", ".noinstr.text"
+#define OTHER_TEXT_SECTIONS ".ref.text", ".head.text", ".spinlock.text", \
+		".fixup", ".entry.text", ".exception.text", ".text.*", \
+		".coldtext", ".softirqentry.text"
+
+#define INIT_SECTIONS      ".init.*"
+#define MEM_INIT_SECTIONS  ".meminit.*"
+
+#define EXIT_SECTIONS      ".exit.*"
+#define MEM_EXIT_SECTIONS  ".memexit.*"
+
+#define ALL_TEXT_SECTIONS  ALL_INIT_TEXT_SECTIONS, ALL_EXIT_TEXT_SECTIONS, \
+		TEXT_SECTIONS, OTHER_TEXT_SECTIONS
+
+/* init data sections */
+static const char *const init_data_sections[] =
+	{ ALL_INIT_DATA_SECTIONS, NULL };
+
+/* all init sections */
+static const char *const init_sections[] = { ALL_INIT_SECTIONS, NULL };
+
+/* all text sections */
+static const char *const text_sections[] = { ALL_TEXT_SECTIONS, NULL };
+
+/* data section */
+static const char *const data_sections[] = { DATA_SECTIONS, NULL };
+
+static const char *const head_sections[] = { ".head.text*", NULL };
+static const char *const linker_symbols[] =
+	{ "__init_begin", "_sinittext", "_einittext", NULL };
+static const char *const optim_symbols[] = { "*.constprop.*", 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,
+	EXTABLE_TO_NON_TEXT,
+};
+
+/**
+ * Describe how to match sections on different criteria:
+ *
+ * @fromsec: Array of sections to be matched.
+ *
+ * @bad_tosec: Relocations applied to a section in @fromsec to a section in
+ * this array is forbidden (black-list).  Can be empty.
+ *
+ * @good_tosec: Relocations applied to a section in @fromsec must be
+ * targeting sections in this array (white-list).  Can be empty.
+ *
+ * @mismatch: Type of mismatch.
+ *
+ * @handler: Specific handler to call when a match is found.  If NULL,
+ * default_mismatch_handler() will be called.
+ *
+ */
+struct sectioncheck {
+	const char *fromsec[20];
+	const char *bad_tosec[20];
+	const char *good_tosec[20];
+	enum mismatch mismatch;
+	void (*handler)(const char *modname, struct elf_info *elf,
+			const struct sectioncheck* const mismatch,
+			Elf_Rela *r, Elf_Sym *sym, const char *fromsec);
+
+};
+
+static void extable_mismatch_handler(const char *modname, struct elf_info *elf,
+				     const struct sectioncheck* const mismatch,
+				     Elf_Rela *r, Elf_Sym *sym,
+				     const char *fromsec);
+
+static const struct sectioncheck sectioncheck[] = {
+/* Do not reference init/exit code/data from
+ * normal code and data
+ */
+{
+	.fromsec = { TEXT_SECTIONS, NULL },
+	.bad_tosec = { ALL_INIT_SECTIONS, NULL },
+	.mismatch = TEXT_TO_ANY_INIT,
+},
+{
+	.fromsec = { DATA_SECTIONS, NULL },
+	.bad_tosec = { ALL_XXXINIT_SECTIONS, NULL },
+	.mismatch = DATA_TO_ANY_INIT,
+},
+{
+	.fromsec = { DATA_SECTIONS, NULL },
+	.bad_tosec = { INIT_SECTIONS, NULL },
+	.mismatch = DATA_TO_ANY_INIT,
+},
+{
+	.fromsec = { TEXT_SECTIONS, NULL },
+	.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+	.mismatch = TEXT_TO_ANY_EXIT,
+},
+{
+	.fromsec = { DATA_SECTIONS, NULL },
+	.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+	.mismatch = DATA_TO_ANY_EXIT,
+},
+/* Do not reference init code/data from meminit code/data */
+{
+	.fromsec = { ALL_XXXINIT_SECTIONS, NULL },
+	.bad_tosec = { INIT_SECTIONS, NULL },
+	.mismatch = XXXINIT_TO_SOME_INIT,
+},
+/* Do not reference exit code/data from memexit code/data */
+{
+	.fromsec = { ALL_XXXEXIT_SECTIONS, NULL },
+	.bad_tosec = { EXIT_SECTIONS, NULL },
+	.mismatch = XXXEXIT_TO_SOME_EXIT,
+},
+/* Do not use exit code/data from init code */
+{
+	.fromsec = { ALL_INIT_SECTIONS, NULL },
+	.bad_tosec = { ALL_EXIT_SECTIONS, NULL },
+	.mismatch = ANY_INIT_TO_ANY_EXIT,
+},
+/* Do not use init code/data from exit code */
+{
+	.fromsec = { ALL_EXIT_SECTIONS, NULL },
+	.bad_tosec = { ALL_INIT_SECTIONS, NULL },
+	.mismatch = ANY_EXIT_TO_ANY_INIT,
+},
+{
+	.fromsec = { ALL_PCI_INIT_SECTIONS, NULL },
+	.bad_tosec = { INIT_SECTIONS, NULL },
+	.mismatch = ANY_INIT_TO_ANY_EXIT,
+},
+/* Do not export init/exit functions or data */
+{
+	.fromsec = { "___ksymtab*", NULL },
+	.bad_tosec = { INIT_SECTIONS, EXIT_SECTIONS, NULL },
+	.mismatch = EXPORT_TO_INIT_EXIT,
+},
+{
+	.fromsec = { "__ex_table", NULL },
+	/* If you're adding any new black-listed sections in here, consider
+	 * adding a special 'printer' for them in scripts/check_extable.
+	 */
+	.bad_tosec = { ".altinstr_replacement", NULL },
+	.good_tosec = {ALL_TEXT_SECTIONS , NULL},
+	.mismatch = EXTABLE_TO_NON_TEXT,
+	.handler = extable_mismatch_handler,
+}
+};
+
+static const struct sectioncheck *section_mismatch(
+		const char *fromsec, const char *tosec)
+{
+	int i;
+
+	/*
+	 * The target section could be the SHT_NUL section when we're
+	 * handling relocations to un-resolved symbols, trying to match it
+	 * doesn't make much sense and causes build failures on parisc
+	 * architectures.
+	 */
+	if (*tosec == '\0')
+		return NULL;
+
+	for (i = 0; i < ARRAY_SIZE(sectioncheck); i++) {
+		const struct sectioncheck *check = &sectioncheck[i];
+
+		if (match(fromsec, check->fromsec)) {
+			if (check->bad_tosec[0] && match(tosec, check->bad_tosec))
+				return check;
+			if (check->good_tosec[0] && !match(tosec, check->good_tosec))
+				return check;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * 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 1a:
+ *   module_param_call() ops can refer to __init set function if permissions=0
+ *   The pattern is identified by:
+ *   tosec   = .init.text
+ *   fromsec = .data*
+ *   atsym   = __param_ops_*
+ *
+ * Pattern 3:
+ *   Whitelist all references from .head.text to any init section
+ *
+ * Pattern 4:
+ *   Some symbols belong to init section but still it is ok to reference
+ *   these from non-init sections as these symbols don't have any memory
+ *   allocated for them and symbol address and value are same. So even
+ *   if init section is freed, its ok to reference those symbols.
+ *   For ex. symbols marking the init section boundaries.
+ *   This pattern is identified by
+ *   refsymname = __init_begin, _sinittext, _einittext
+ *
+ * Pattern 5:
+ *   GCC may optimize static inlines when fed constant arg(s) resulting
+ *   in functions like cpumask_empty() -- generating an associated symbol
+ *   cpumask_empty.constprop.3 that appears in the audit.  If the const that
+ *   is passed in comes from __init, like say nmi_ipi_mask, we get a
+ *   meaningless section warning.  May need to add isra symbols too...
+ *   This pattern is identified by
+ *   tosec   = init section
+ *   fromsec = text section
+ *   refsymname = *.constprop.*
+ *
+ * Pattern 6:
+ *   Hide section mismatch warnings for ELF local symbols.  The goal
+ *   is to eliminate false positive modpost warnings caused by
+ *   compiler-generated ELF local symbol names such as ".LANCHOR1".
+ *   Autogenerated symbol names bypass modpost's "Pattern 2"
+ *   whitelisting, which relies on pattern-matching against symbol
+ *   names to work.  (One situation where gcc can autogenerate ELF
+ *   local symbols is when "-fsection-anchors" is used.)
+ **/
+static int secref_whitelist(const struct sectioncheck *mismatch,
+			    const char *fromsec, const char *fromsym,
+			    const char *tosec, const char *tosym)
+{
+	/* Check for pattern 1 */
+	if (match(tosec, init_data_sections) &&
+	    match(fromsec, data_sections) &&
+	    strstarts(fromsym, "__param"))
+		return 0;
+
+	/* Check for pattern 1a */
+	if (strcmp(tosec, ".init.text") == 0 &&
+	    match(fromsec, data_sections) &&
+	    strstarts(fromsym, "__param_ops_"))
+		return 0;
+
+	/* symbols in data sections that may refer to any init/exit sections */
+	if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
+	    match(tosec, PATTERNS(ALL_INIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
+	    match(fromsym, PATTERNS("*_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")))
+		return 0;
+
+	/* symbols in data sections that may refer to meminit/exit sections */
+	if (match(fromsec, PATTERNS(DATA_SECTIONS)) &&
+	    match(tosec, PATTERNS(ALL_XXXINIT_SECTIONS, ALL_EXIT_SECTIONS)) &&
+	    match(fromsym, PATTERNS("*driver")))
+		return 0;
+
+	/* Check for pattern 3 */
+	if (match(fromsec, head_sections) &&
+	    match(tosec, init_sections))
+		return 0;
+
+	/* Check for pattern 4 */
+	if (match(tosym, linker_symbols))
+		return 0;
+
+	/* Check for pattern 5 */
+	if (match(fromsec, text_sections) &&
+	    match(tosec, init_sections) &&
+	    match(fromsym, optim_symbols))
+		return 0;
+
+	/* Check for pattern 6 */
+	if (strstarts(fromsym, ".L"))
+		return 0;
+
+	return 1;
+}
+
+static inline int is_arm_mapping_symbol(const char *str)
+{
+	return str[0] == '$' &&
+	       (str[1] == 'a' || str[1] == 'd' || str[1] == 't' || str[1] == 'x')
+	       && (str[2] == '\0' || str[2] == '.');
+}
+
+/*
+ * If there's no name there, ignore it; likewise, ignore it if it's
+ * one of the magic symbols emitted used by current ARM tools.
+ *
+ * Otherwise if find_symbols_between() returns those symbols, they'll
+ * fail the whitelist tests and cause lots of false alarms ... fixable
+ * only by merging __exit and __init sections into __text, bloating
+ * the kernel (which is especially evil on embedded platforms).
+ */
+static inline int is_valid_name(struct elf_info *elf, Elf_Sym *sym)
+{
+	const char *name = elf->strtab + sym->st_name;
+
+	if (!name || !strlen(name))
+		return 0;
+	return !is_arm_mapping_symbol(name);
+}
+
+/**
+ * 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, Elf64_Sword addr,
+				Elf_Sym *relsym)
+{
+	Elf_Sym *sym;
+	Elf_Sym *near = NULL;
+	Elf64_Sword distance = 20;
+	Elf64_Sword d;
+	unsigned int relsym_secindex;
+
+	if (relsym->st_name != 0)
+		return relsym;
+
+	/*
+	 * Strive to find a better symbol name, but the resulting name may not
+	 * match the symbol referenced in the original code.
+	 */
+	relsym_secindex = get_secindex(elf, relsym);
+	for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+		if (get_secindex(elf, sym) != relsym_secindex)
+			continue;
+		if (ELF_ST_TYPE(sym->st_info) == STT_SECTION)
+			continue;
+		if (!is_valid_name(elf, sym))
+			continue;
+		if (sym->st_value == addr)
+			return sym;
+		/* Find a symbol nearby - addr are maybe negative */
+		d = sym->st_value - addr;
+		if (d < 0)
+			d = addr - sym->st_value;
+		if (d < distance) {
+			distance = d;
+			near = sym;
+		}
+	}
+	/* We need a close match */
+	if (distance < 20)
+		return near;
+	else
+		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 Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
+				 const char *sec)
+{
+	Elf_Sym *sym;
+	Elf_Sym *near = NULL;
+	Elf_Addr distance = ~0;
+
+	for (sym = elf->symtab_start; sym < elf->symtab_stop; sym++) {
+		const char *symsec;
+
+		if (is_shndx_special(sym->st_shndx))
+			continue;
+		symsec = sec_name(elf, get_secindex(elf, sym));
+		if (strcmp(symsec, sec) != 0)
+			continue;
+		if (!is_valid_name(elf, sym))
+			continue;
+		if (sym->st_value <= addr && addr - sym->st_value <= distance) {
+			distance = addr - sym->st_value;
+			near = sym;
+		}
+	}
+	return near;
+}
+
+static int is_function(Elf_Sym *sym)
+{
+	if (sym)
+		return ELF_ST_TYPE(sym->st_info) == STT_FUNC;
+	else
+		return -1;
+}
+
+static inline void get_pretty_name(int is_func, const char** name, const char** name_p)
+{
+	switch (is_func) {
+	case 0:	*name = "variable"; *name_p = ""; break;
+	case 1:	*name = "function"; *name_p = "()"; break;
+	default: *name = "(unknown reference)"; *name_p = ""; break;
+	}
+}
+
+/*
+ * 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 report_sec_mismatch(const char *modname,
+				const struct sectioncheck *mismatch,
+				const char *fromsec,
+				const char *fromsym,
+				const char *tosec, const char *tosym)
+{
+	sec_mismatch_count++;
+
+	switch (mismatch->mismatch) {
+	case TEXT_TO_ANY_INIT:
+	case DATA_TO_ANY_INIT:
+	case TEXT_TO_ANY_EXIT:
+	case DATA_TO_ANY_EXIT:
+	case XXXINIT_TO_SOME_INIT:
+	case XXXEXIT_TO_SOME_EXIT:
+	case ANY_INIT_TO_ANY_EXIT:
+	case ANY_EXIT_TO_ANY_INIT:
+		warn("%s: section mismatch in reference: %s (section: %s) -> %s (section: %s)\n",
+		     modname, fromsym, fromsec, tosym, tosec);
+		break;
+	case EXPORT_TO_INIT_EXIT:
+		warn("%s: EXPORT_SYMBOL used for init/exit symbol: %s (section: %s)\n",
+		     modname, tosym, tosec);
+		break;
+	case EXTABLE_TO_NON_TEXT:
+		fatal("There's a special handler for this mismatch type, we should never get here.\n");
+		break;
+	}
+}
+
+static void default_mismatch_handler(const char *modname, struct elf_info *elf,
+				     const struct sectioncheck* const mismatch,
+				     Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+{
+	const char *tosec;
+	Elf_Sym *to;
+	Elf_Sym *from;
+	const char *tosym;
+	const char *fromsym;
+
+	from = find_elf_symbol2(elf, r->r_offset, fromsec);
+	fromsym = sym_name(elf, from);
+
+	tosec = sec_name(elf, get_secindex(elf, sym));
+	to = find_elf_symbol(elf, r->r_addend, sym);
+	tosym = sym_name(elf, to);
+
+	/* check whitelist - we may ignore it */
+	if (secref_whitelist(mismatch,
+			     fromsec, fromsym, tosec, tosym)) {
+		report_sec_mismatch(modname, mismatch,
+				    fromsec, fromsym, tosec, tosym);
+	}
+}
+
+static int is_executable_section(struct elf_info* elf, unsigned int section_index)
+{
+	if (section_index >= elf->num_sections)
+		fatal("section_index is outside elf->num_sections!\n");
+
+	return ((elf->sechdrs[section_index].sh_flags & SHF_EXECINSTR) == SHF_EXECINSTR);
+}
+
+static void report_extable_warnings(const char* modname, struct elf_info* elf,
+				    const struct sectioncheck* const mismatch,
+				    Elf_Rela* r, Elf_Sym* sym,
+				    const char* fromsec, const char* tosec)
+{
+	Elf_Sym* fromsym = find_elf_symbol2(elf, r->r_offset, fromsec);
+	const char* fromsym_name = sym_name(elf, fromsym);
+	Elf_Sym* tosym = find_elf_symbol(elf, r->r_addend, sym);
+	const char* tosym_name = sym_name(elf, tosym);
+	const char* from_pretty_name;
+	const char* from_pretty_name_p;
+	const char* to_pretty_name;
+	const char* to_pretty_name_p;
+
+	get_pretty_name(is_function(fromsym),
+			&from_pretty_name, &from_pretty_name_p);
+	get_pretty_name(is_function(tosym),
+			&to_pretty_name, &to_pretty_name_p);
+
+	warn("%s(%s+0x%lx): Section mismatch in reference"
+	     " from the %s %s%s to the %s %s:%s%s\n",
+	     modname, fromsec, (long)r->r_offset, from_pretty_name,
+	     fromsym_name, from_pretty_name_p,
+	     to_pretty_name, tosec, tosym_name, to_pretty_name_p);
+
+	if (!match(tosec, mismatch->bad_tosec) &&
+	    is_executable_section(elf, get_secindex(elf, sym)))
+		fprintf(stderr,
+			"The relocation at %s+0x%lx references\n"
+			"section \"%s\" which is not in the list of\n"
+			"authorized sections.  If you're adding a new section\n"
+			"and/or if this reference is valid, add \"%s\" to the\n"
+			"list of authorized sections to jump to on fault.\n"
+			"This can be achieved by adding \"%s\" to \n"
+			"OTHER_TEXT_SECTIONS in scripts/mod/modpost.c.\n",
+			fromsec, (long)r->r_offset, tosec, tosec, tosec);
+}
+
+static void extable_mismatch_handler(const char* modname, struct elf_info *elf,
+				     const struct sectioncheck* const mismatch,
+				     Elf_Rela* r, Elf_Sym* sym,
+				     const char *fromsec)
+{
+	const char* tosec = sec_name(elf, get_secindex(elf, sym));
+
+	sec_mismatch_count++;
+
+	report_extable_warnings(modname, elf, mismatch, r, sym, fromsec, tosec);
+
+	if (match(tosec, mismatch->bad_tosec))
+		fatal("The relocation at %s+0x%lx references\n"
+		      "section \"%s\" which is black-listed.\n"
+		      "Something is seriously wrong and should be fixed.\n"
+		      "You might get more information about where this is\n"
+		      "coming from by using scripts/check_extable.sh %s\n",
+		      fromsec, (long)r->r_offset, tosec, modname);
+	else if (!is_executable_section(elf, get_secindex(elf, sym)))
+		error("%s+0x%lx references non-executable section '%s'\n",
+		      fromsec, (long)r->r_offset, tosec);
+}
+
+static void check_section_mismatch(const char *modname, struct elf_info *elf,
+				   Elf_Rela *r, Elf_Sym *sym, const char *fromsec)
+{
+	const char *tosec = sec_name(elf, get_secindex(elf, sym));
+	const struct sectioncheck *mismatch = section_mismatch(fromsec, tosec);
+
+	if (mismatch) {
+		if (mismatch->handler)
+			mismatch->handler(modname, elf,  mismatch,
+					  r, sym, fromsec);
+		else
+			default_mismatch_handler(modname, elf, mismatch,
+						 r, sym, fromsec);
+	}
+}
+
+static unsigned int *reloc_location(struct elf_info *elf,
+				    Elf_Shdr *sechdr, Elf_Rela *r)
+{
+	return sym_get_data_by_offset(elf, sechdr->sh_info, r->r_offset);
+}
+
+static int addend_386_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+	unsigned int r_typ = ELF_R_TYPE(r->r_info);
+	unsigned int *location = reloc_location(elf, sechdr, r);
+
+	switch (r_typ) {
+	case R_386_32:
+		r->r_addend = TO_NATIVE(*location);
+		break;
+	case R_386_PC32:
+		r->r_addend = TO_NATIVE(*location) + 4;
+		break;
+	}
+	return 0;
+}
+
+#ifndef R_ARM_CALL
+#define R_ARM_CALL	28
+#endif
+#ifndef R_ARM_JUMP24
+#define R_ARM_JUMP24	29
+#endif
+
+#ifndef	R_ARM_THM_CALL
+#define	R_ARM_THM_CALL		10
+#endif
+#ifndef	R_ARM_THM_JUMP24
+#define	R_ARM_THM_JUMP24	30
+#endif
+#ifndef	R_ARM_THM_JUMP19
+#define	R_ARM_THM_JUMP19	51
+#endif
+
+static int32_t sign_extend32(int32_t value, int index)
+{
+	uint8_t shift = 31 - index;
+
+	return (int32_t)(value << shift) >> shift;
+}
+
+static int addend_arm_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+	unsigned int r_typ = ELF_R_TYPE(r->r_info);
+	Elf_Sym *sym = elf->symtab_start + ELF_R_SYM(r->r_info);
+	void *loc = reloc_location(elf, sechdr, r);
+	uint32_t inst;
+	int32_t offset;
+
+	switch (r_typ) {
+	case R_ARM_ABS32:
+		inst = TO_NATIVE(*(uint32_t *)loc);
+		r->r_addend = inst + sym->st_value;
+		break;
+	case R_ARM_PC24:
+	case R_ARM_CALL:
+	case R_ARM_JUMP24:
+		inst = TO_NATIVE(*(uint32_t *)loc);
+		offset = sign_extend32((inst & 0x00ffffff) << 2, 25);
+		r->r_addend = offset + sym->st_value + 8;
+		break;
+	case R_ARM_THM_CALL:
+	case R_ARM_THM_JUMP24:
+	case R_ARM_THM_JUMP19:
+		/* From ARM ABI: ((S + A) | T) - P */
+		r->r_addend = (int)(long)(elf->hdr +
+			      sechdr->sh_offset +
+			      (r->r_offset - sechdr->sh_addr));
+		break;
+	default:
+		return 1;
+	}
+	return 0;
+}
+
+static int addend_mips_rel(struct elf_info *elf, Elf_Shdr *sechdr, Elf_Rela *r)
+{
+	unsigned int r_typ = ELF_R_TYPE(r->r_info);
+	unsigned int *location = reloc_location(elf, sechdr, r);
+	unsigned int inst;
+
+	if (r_typ == R_MIPS_HI16)
+		return 1;	/* skip this */
+	inst = TO_NATIVE(*location);
+	switch (r_typ) {
+	case R_MIPS_LO16:
+		r->r_addend = inst & 0xffff;
+		break;
+	case R_MIPS_26:
+		r->r_addend = (inst & 0x03ffffff) << 2;
+		break;
+	case R_MIPS_32:
+		r->r_addend = inst;
+		break;
+	}
+	return 0;
+}
+
+#ifndef EM_RISCV
+#define EM_RISCV		243
+#endif
+
+#ifndef R_RISCV_SUB32
+#define R_RISCV_SUB32		39
+#endif
+
+static void section_rela(const char *modname, struct elf_info *elf,
+			 Elf_Shdr *sechdr)
+{
+	Elf_Sym  *sym;
+	Elf_Rela *rela;
+	Elf_Rela r;
+	unsigned int r_sym;
+	const char *fromsec;
+
+	Elf_Rela *start = (void *)elf->hdr + sechdr->sh_offset;
+	Elf_Rela *stop  = (void *)start + sechdr->sh_size;
+
+	fromsec = sec_name(elf, sechdr->sh_info);
+	/* if from section (name) is know good then skip it */
+	if (match(fromsec, section_white_list))
+		return;
+
+	for (rela = start; rela < stop; rela++) {
+		r.r_offset = TO_NATIVE(rela->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+		if (elf->hdr->e_machine == EM_MIPS) {
+			unsigned int r_typ;
+			r_sym = ELF64_MIPS_R_SYM(rela->r_info);
+			r_sym = TO_NATIVE(r_sym);
+			r_typ = ELF64_MIPS_R_TYPE(rela->r_info);
+			r.r_info = ELF64_R_INFO(r_sym, r_typ);
+		} else {
+			r.r_info = TO_NATIVE(rela->r_info);
+			r_sym = ELF_R_SYM(r.r_info);
+		}
+#else
+		r.r_info = TO_NATIVE(rela->r_info);
+		r_sym = ELF_R_SYM(r.r_info);
+#endif
+		r.r_addend = TO_NATIVE(rela->r_addend);
+		switch (elf->hdr->e_machine) {
+		case EM_RISCV:
+			if (!strcmp("__ex_table", fromsec) &&
+			    ELF_R_TYPE(r.r_info) == R_RISCV_SUB32)
+				continue;
+			break;
+		}
+		sym = elf->symtab_start + r_sym;
+		/* Skip special sections */
+		if (is_shndx_special(sym->st_shndx))
+			continue;
+		check_section_mismatch(modname, elf, &r, sym, fromsec);
+	}
+}
+
+static void section_rel(const char *modname, struct elf_info *elf,
+			Elf_Shdr *sechdr)
+{
+	Elf_Sym *sym;
+	Elf_Rel *rel;
+	Elf_Rela r;
+	unsigned int r_sym;
+	const char *fromsec;
+
+	Elf_Rel *start = (void *)elf->hdr + sechdr->sh_offset;
+	Elf_Rel *stop  = (void *)start + sechdr->sh_size;
+
+	fromsec = sec_name(elf, sechdr->sh_info);
+	/* if from section (name) is know good then skip it */
+	if (match(fromsec, section_white_list))
+		return;
+
+	for (rel = start; rel < stop; rel++) {
+		r.r_offset = TO_NATIVE(rel->r_offset);
+#if KERNEL_ELFCLASS == ELFCLASS64
+		if (elf->hdr->e_machine == EM_MIPS) {
+			unsigned int r_typ;
+			r_sym = ELF64_MIPS_R_SYM(rel->r_info);
+			r_sym = TO_NATIVE(r_sym);
+			r_typ = ELF64_MIPS_R_TYPE(rel->r_info);
+			r.r_info = ELF64_R_INFO(r_sym, r_typ);
+		} else {
+			r.r_info = TO_NATIVE(rel->r_info);
+			r_sym = ELF_R_SYM(r.r_info);
+		}
+#else
+		r.r_info = TO_NATIVE(rel->r_info);
+		r_sym = ELF_R_SYM(r.r_info);
+#endif
+		r.r_addend = 0;
+		switch (elf->hdr->e_machine) {
+		case EM_386:
+			if (addend_386_rel(elf, sechdr, &r))
+				continue;
+			break;
+		case EM_ARM:
+			if (addend_arm_rel(elf, sechdr, &r))
+				continue;
+			break;
+		case EM_MIPS:
+			if (addend_mips_rel(elf, sechdr, &r))
+				continue;
+			break;
+		}
+		sym = elf->symtab_start + r_sym;
+		/* Skip special sections */
+		if (is_shndx_special(sym->st_shndx))
+			continue;
+		check_section_mismatch(modname, elf, &r, sym, fromsec);
+	}
+}
+
+/**
+ * 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 initialized.
+ * Likewise for modules used built-in the sections marked __exit
+ * are discarded because __exit marked function are supposed to be called
+ * only when a module is unloaded which never happens 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(const char *modname, struct elf_info *elf)
+{
+	int i;
+	Elf_Shdr *sechdrs = elf->sechdrs;
+
+	/* Walk through all sections */
+	for (i = 0; i < elf->num_sections; i++) {
+		check_section(modname, elf, &elf->sechdrs[i]);
+		/* We want to process only relocation sections and not .init */
+		if (sechdrs[i].sh_type == SHT_RELA)
+			section_rela(modname, elf, &elf->sechdrs[i]);
+		else if (sechdrs[i].sh_type == SHT_REL)
+			section_rel(modname, elf, &elf->sechdrs[i]);
+	}
+}
+
+static char *remove_dot(char *s)
+{
+	size_t n = strcspn(s, ".");
+
+	if (n && s[n]) {
+		size_t m = strspn(s + n + 1, "0123456789");
+		if (m && (s[n + m + 1] == '.' || s[n + m + 1] == 0))
+			s[n] = 0;
+	}
+	return s;
+}
+
+/*
+ * The CRCs are recorded in .*.cmd files in the form of:
+ * #SYMVER <name> <crc>
+ */
+static void extract_crcs_for_object(const char *object, struct module *mod)
+{
+	char cmd_file[PATH_MAX];
+	char *buf, *p;
+	const char *base;
+	int dirlen, ret;
+
+	base = strrchr(object, '/');
+	if (base) {
+		base++;
+		dirlen = base - object;
+	} else {
+		dirlen = 0;
+		base = object;
+	}
+
+	ret = snprintf(cmd_file, sizeof(cmd_file), "%.*s.%s.cmd",
+		       dirlen, object, base);
+	if (ret >= sizeof(cmd_file)) {
+		error("%s: too long path was truncated\n", cmd_file);
+		return;
+	}
+
+	buf = read_text_file(cmd_file);
+	p = buf;
+
+	while ((p = strstr(p, "\n#SYMVER "))) {
+		char *name;
+		size_t namelen;
+		unsigned int crc;
+		struct symbol *sym;
+
+		name = p + strlen("\n#SYMVER ");
+
+		p = strchr(name, ' ');
+		if (!p)
+			break;
+
+		namelen = p - name;
+		p++;
+
+		if (!isdigit(*p))
+			continue;	/* skip this line */
+
+		crc = strtoul(p, &p, 0);
+		if (*p != '\n')
+			continue;	/* skip this line */
+
+		name[namelen] = '\0';
+
+		/*
+		 * sym_find_with_module() may return NULL here.
+		 * It typically occurs when CONFIG_TRIM_UNUSED_KSYMS=y.
+		 * Since commit e1327a127703, genksyms calculates CRCs of all
+		 * symbols, including trimmed ones. Ignore orphan CRCs.
+		 */
+		sym = sym_find_with_module(name, mod);
+		if (sym)
+			sym_set_crc(sym, crc);
+	}
+
+	free(buf);
+}
+
+/*
+ * The symbol versions (CRC) are recorded in the .*.cmd files.
+ * Parse them to retrieve CRCs for the current module.
+ */
+static void mod_set_crcs(struct module *mod)
+{
+	char objlist[PATH_MAX];
+	char *buf, *p, *obj;
+	int ret;
+
+	if (mod->is_vmlinux) {
+		strcpy(objlist, ".vmlinux.objs");
+	} else {
+		/* objects for a module are listed in the *.mod file. */
+		ret = snprintf(objlist, sizeof(objlist), "%s.mod", mod->name);
+		if (ret >= sizeof(objlist)) {
+			error("%s: too long path was truncated\n", objlist);
+			return;
+		}
+	}
+
+	buf = read_text_file(objlist);
+	p = buf;
+
+	while ((obj = strsep(&p, "\n")) && obj[0])
+		extract_crcs_for_object(obj, mod);
+
+	free(buf);
+}
+
+static void read_symbols(const char *modname)
+{
+	const char *symname;
+	char *version;
+	char *license;
+	char *namespace;
+	struct module *mod;
+	struct elf_info info = { };
+	Elf_Sym *sym;
+
+	if (!parse_elf(&info, modname))
+		return;
+
+	if (!strends(modname, ".o")) {
+		error("%s: filename must be suffixed with .o\n", modname);
+		return;
+	}
+
+	/* strip trailing .o */
+	mod = new_module(modname, strlen(modname) - strlen(".o"));
+
+	if (!mod->is_vmlinux) {
+		license = get_modinfo(&info, "license");
+		if (!license)
+			error("missing MODULE_LICENSE() in %s\n", modname);
+		while (license) {
+			if (!license_is_gpl_compatible(license)) {
+				mod->is_gpl_compatible = false;
+				break;
+			}
+			license = get_next_modinfo(&info, "license", license);
+		}
+
+		namespace = get_modinfo(&info, "import_ns");
+		while (namespace) {
+			add_namespace(&mod->imported_namespaces, namespace);
+			namespace = get_next_modinfo(&info, "import_ns",
+						     namespace);
+		}
+	}
+
+	for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
+		symname = remove_dot(info.strtab + sym->st_name);
+
+		handle_symbol(mod, &info, sym, symname);
+		handle_moddevtable(mod, &info, sym, symname);
+	}
+
+	for (sym = info.symtab_start; sym < info.symtab_stop; sym++) {
+		symname = remove_dot(info.strtab + sym->st_name);
+
+		/* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
+		if (strstarts(symname, "__kstrtabns_"))
+			sym_update_namespace(symname + strlen("__kstrtabns_"),
+					     sym_get_data(&info, sym));
+	}
+
+	check_sec_ref(modname, &info);
+
+	if (!mod->is_vmlinux) {
+		version = get_modinfo(&info, "version");
+		if (version || all_versions)
+			get_src_version(mod->name, mod->srcversion,
+					sizeof(mod->srcversion) - 1);
+	}
+
+	parse_elf_finish(&info);
+
+	if (modversions) {
+		/*
+		 * Our trick to get versioning for module struct etc. - it's
+		 * never passed as an argument to an exported function, so
+		 * the automatic versioning doesn't pick it up, but it's really
+		 * important anyhow.
+		 */
+		sym_add_unresolved("module_layout", mod, false);
+
+		mod_set_crcs(mod);
+	}
+}
+
+static void read_symbols_from_files(const char *filename)
+{
+	FILE *in = stdin;
+	char fname[PATH_MAX];
+
+	if (strcmp(filename, "-") != 0) {
+		in = fopen(filename, "r");
+		if (!in)
+			fatal("Can't open filenames file %s: %m", filename);
+	}
+
+	while (fgets(fname, PATH_MAX, in) != NULL) {
+		if (strends(fname, "\n"))
+			fname[strlen(fname)-1] = '\0';
+		read_symbols(fname);
+	}
+
+	if (in != stdin)
+		fclose(in);
+}
+
+#define SZ 500
+
+/* We first write the generated file into memory using the
+ * 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, ...)
+{
+	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)
+{
+	if (buf->size - buf->pos < len) {
+		buf->size += len + SZ;
+		buf->p = NOFAIL(realloc(buf->p, buf->size));
+	}
+	strncpy(buf->p + buf->pos, s, len);
+	buf->pos += len;
+}
+
+static void check_exports(struct module *mod)
+{
+	struct symbol *s, *exp;
+
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
+		const char *basename;
+		exp = find_symbol(s->name);
+		if (!exp) {
+			if (!s->weak && nr_unresolved++ < MAX_UNRESOLVED_REPORTS)
+				modpost_log(warn_unresolved ? LOG_WARN : LOG_ERROR,
+					    "\"%s\" [%s.ko] undefined!\n",
+					    s->name, mod->name);
+			continue;
+		}
+		if (exp->module == mod) {
+			error("\"%s\" [%s.ko] was exported without definition\n",
+			      s->name, mod->name);
+			continue;
+		}
+
+		s->module = exp->module;
+		s->crc_valid = exp->crc_valid;
+		s->crc = exp->crc;
+
+		basename = strrchr(mod->name, '/');
+		if (basename)
+			basename++;
+		else
+			basename = mod->name;
+
+		if (exp->namespace &&
+		    !contains_namespace(&mod->imported_namespaces, exp->namespace)) {
+			modpost_log(allow_missing_ns_imports ? LOG_WARN : LOG_ERROR,
+				    "module %s uses symbol %s from namespace %s, but does not import it.\n",
+				    basename, exp->name, exp->namespace);
+			add_namespace(&mod->missing_namespaces, exp->namespace);
+		}
+
+		if (!mod->is_gpl_compatible && exp->is_gpl_only)
+			error("GPL-incompatible module %s.ko uses GPL-only symbol '%s'\n",
+			      basename, exp->name);
+	}
+}
+
+static void check_modname_len(struct module *mod)
+{
+	const char *mod_name;
+
+	mod_name = strrchr(mod->name, '/');
+	if (mod_name == NULL)
+		mod_name = mod->name;
+	else
+		mod_name++;
+	if (strlen(mod_name) >= MODULE_NAME_LEN)
+		error("module name is too long [%s.ko]\n", mod->name);
+}
+
+/**
+ * Header for the generated file
+ **/
+static void add_header(struct buffer *b, struct module *mod)
+{
+	buf_printf(b, "#include <linux/module.h>\n");
+	/*
+	 * Include build-salt.h after module.h in order to
+	 * inherit the definitions.
+	 */
+	buf_printf(b, "#define INCLUDE_VERMAGIC\n");
+	buf_printf(b, "#include <linux/build-salt.h>\n");
+	buf_printf(b, "#include <linux/elfnote-lto.h>\n");
+	buf_printf(b, "#include <linux/export-internal.h>\n");
+	buf_printf(b, "#include <linux/vermagic.h>\n");
+	buf_printf(b, "#include <linux/compiler.h>\n");
+	buf_printf(b, "\n");
+	buf_printf(b, "BUILD_SALT;\n");
+	buf_printf(b, "BUILD_LTO_INFO;\n");
+	buf_printf(b, "\n");
+	buf_printf(b, "MODULE_INFO(vermagic, VERMAGIC_STRING);\n");
+	buf_printf(b, "MODULE_INFO(name, KBUILD_MODNAME);\n");
+	buf_printf(b, "\n");
+	buf_printf(b, "__visible struct module __this_module\n");
+	buf_printf(b, "__section(\".gnu.linkonce.this_module\") = {\n");
+	buf_printf(b, "\t.name = KBUILD_MODNAME,\n");
+	if (mod->has_init)
+		buf_printf(b, "\t.init = init_module,\n");
+	if (mod->has_cleanup)
+		buf_printf(b, "#ifdef CONFIG_MODULE_UNLOAD\n"
+			      "\t.exit = cleanup_module,\n"
+			      "#endif\n");
+	buf_printf(b, "\t.arch = MODULE_ARCH_INIT,\n");
+	buf_printf(b, "};\n");
+
+	if (!external_module)
+		buf_printf(b, "\nMODULE_INFO(intree, \"Y\");\n");
+
+	buf_printf(b,
+		   "\n"
+		   "#ifdef CONFIG_RETPOLINE\n"
+		   "MODULE_INFO(retpoline, \"Y\");\n"
+		   "#endif\n");
+
+	if (strstarts(mod->name, "drivers/staging"))
+		buf_printf(b, "\nMODULE_INFO(staging, \"Y\");\n");
+
+	if (strstarts(mod->name, "tools/testing"))
+		buf_printf(b, "\nMODULE_INFO(test, \"Y\");\n");
+}
+
+static void add_exported_symbols(struct buffer *buf, struct module *mod)
+{
+	struct symbol *sym;
+
+	if (!modversions)
+		return;
+
+	/* record CRCs for exported symbols */
+	buf_printf(buf, "\n");
+	list_for_each_entry(sym, &mod->exported_symbols, list) {
+		if (!sym->crc_valid)
+			warn("EXPORT symbol \"%s\" [%s%s] version generation failed, symbol will not be versioned.\n"
+			     "Is \"%s\" prototyped in <asm/asm-prototypes.h>?\n",
+			     sym->name, mod->name, mod->is_vmlinux ? "" : ".ko",
+			     sym->name);
+
+		buf_printf(buf, "SYMBOL_CRC(%s, 0x%08x, \"%s\");\n",
+			   sym->name, sym->crc, sym->is_gpl_only ? "_gpl" : "");
+	}
+}
+
+/**
+ * Record CRCs for unresolved symbols
+ **/
+static void add_versions(struct buffer *b, struct module *mod)
+{
+	struct symbol *s;
+
+	if (!modversions)
+		return;
+
+	buf_printf(b, "\n");
+	buf_printf(b, "static const struct modversion_info ____versions[]\n");
+	buf_printf(b, "__used __section(\"__versions\") = {\n");
+
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
+		if (!s->module)
+			continue;
+		if (!s->crc_valid) {
+			warn("\"%s\" [%s.ko] has no CRC!\n",
+				s->name, mod->name);
+			continue;
+		}
+		if (strlen(s->name) >= MODULE_NAME_LEN) {
+			error("too long symbol \"%s\" [%s.ko]\n",
+			      s->name, mod->name);
+			break;
+		}
+		buf_printf(b, "\t{ %#8x, \"%s\" },\n",
+			   s->crc, s->name);
+	}
+
+	buf_printf(b, "};\n");
+}
+
+static void add_depends(struct buffer *b, struct module *mod)
+{
+	struct symbol *s;
+	int first = 1;
+
+	/* Clear ->seen flag of modules that own symbols needed by this. */
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
+		if (s->module)
+			s->module->seen = s->module->is_vmlinux;
+	}
+
+	buf_printf(b, "\n");
+	buf_printf(b, "MODULE_INFO(depends, \"");
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
+		const char *p;
+		if (!s->module)
+			continue;
+
+		if (s->module->seen)
+			continue;
+
+		s->module->seen = true;
+		p = strrchr(s->module->name, '/');
+		if (p)
+			p++;
+		else
+			p = s->module->name;
+		buf_printf(b, "%s%s", first ? "" : ",", p);
+		first = 0;
+	}
+	buf_printf(b, "\");\n");
+}
+
+static void add_srcversion(struct buffer *b, struct module *mod)
+{
+	if (mod->srcversion[0]) {
+		buf_printf(b, "\n");
+		buf_printf(b, "MODULE_INFO(srcversion, \"%s\");\n",
+			   mod->srcversion);
+	}
+}
+
+static void write_buf(struct buffer *b, const char *fname)
+{
+	FILE *file;
+
+	if (error_occurred)
+		return;
+
+	file = fopen(fname, "w");
+	if (!file) {
+		perror(fname);
+		exit(1);
+	}
+	if (fwrite(b->p, 1, b->pos, file) != b->pos) {
+		perror(fname);
+		exit(1);
+	}
+	if (fclose(file) != 0) {
+		perror(fname);
+		exit(1);
+	}
+}
+
+static void write_if_changed(struct buffer *b, const char *fname)
+{
+	char *tmp;
+	FILE *file;
+	struct stat st;
+
+	file = fopen(fname, "r");
+	if (!file)
+		goto write;
+
+	if (fstat(fileno(file), &st) < 0)
+		goto close_write;
+
+	if (st.st_size != b->pos)
+		goto close_write;
+
+	tmp = NOFAIL(malloc(b->pos));
+	if (fread(tmp, 1, b->pos, file) != b->pos)
+		goto free_write;
+
+	if (memcmp(tmp, b->p, b->pos) != 0)
+		goto free_write;
+
+	free(tmp);
+	fclose(file);
+	return;
+
+ free_write:
+	free(tmp);
+ close_write:
+	fclose(file);
+ write:
+	write_buf(b, fname);
+}
+
+static void write_vmlinux_export_c_file(struct module *mod)
+{
+	struct buffer buf = { };
+
+	buf_printf(&buf,
+		   "#include <linux/export-internal.h>\n");
+
+	add_exported_symbols(&buf, mod);
+	write_if_changed(&buf, ".vmlinux.export.c");
+	free(buf.p);
+}
+
+/* do sanity checks, and generate *.mod.c file */
+static void write_mod_c_file(struct module *mod)
+{
+	struct buffer buf = { };
+	char fname[PATH_MAX];
+	int ret;
+
+	check_modname_len(mod);
+	check_exports(mod);
+
+	add_header(&buf, mod);
+	add_exported_symbols(&buf, mod);
+	add_versions(&buf, mod);
+	add_depends(&buf, mod);
+	add_moddevtable(&buf, mod);
+	add_srcversion(&buf, mod);
+
+	ret = snprintf(fname, sizeof(fname), "%s.mod.c", mod->name);
+	if (ret >= sizeof(fname)) {
+		error("%s: too long path was truncated\n", fname);
+		goto free;
+	}
+
+	write_if_changed(&buf, fname);
+
+free:
+	free(buf.p);
+}
+
+/* parse Module.symvers file. line format:
+ * 0x12345678<tab>symbol<tab>module<tab>export<tab>namespace
+ **/
+static void read_dump(const char *fname)
+{
+	char *buf, *pos, *line;
+
+	buf = read_text_file(fname);
+	if (!buf)
+		/* No symbol versions, silently ignore */
+		return;
+
+	pos = buf;
+
+	while ((line = get_line(&pos))) {
+		char *symname, *namespace, *modname, *d, *export;
+		unsigned int crc;
+		struct module *mod;
+		struct symbol *s;
+		bool gpl_only;
+
+		if (!(symname = strchr(line, '\t')))
+			goto fail;
+		*symname++ = '\0';
+		if (!(modname = strchr(symname, '\t')))
+			goto fail;
+		*modname++ = '\0';
+		if (!(export = strchr(modname, '\t')))
+			goto fail;
+		*export++ = '\0';
+		if (!(namespace = strchr(export, '\t')))
+			goto fail;
+		*namespace++ = '\0';
+
+		crc = strtoul(line, &d, 16);
+		if (*symname == '\0' || *modname == '\0' || *d != '\0')
+			goto fail;
+
+		if (!strcmp(export, "EXPORT_SYMBOL_GPL")) {
+			gpl_only = true;
+		} else if (!strcmp(export, "EXPORT_SYMBOL")) {
+			gpl_only = false;
+		} else {
+			error("%s: unknown license %s. skip", symname, export);
+			continue;
+		}
+
+		mod = find_module(modname);
+		if (!mod) {
+			mod = new_module(modname, strlen(modname));
+			mod->from_dump = true;
+		}
+		s = sym_add_exported(symname, mod, gpl_only);
+		sym_set_crc(s, crc);
+		sym_update_namespace(symname, namespace);
+	}
+	free(buf);
+	return;
+fail:
+	free(buf);
+	fatal("parse error in symbol dump file\n");
+}
+
+static void write_dump(const char *fname)
+{
+	struct buffer buf = { };
+	struct module *mod;
+	struct symbol *sym;
+
+	list_for_each_entry(mod, &modules, list) {
+		if (mod->from_dump)
+			continue;
+		list_for_each_entry(sym, &mod->exported_symbols, list) {
+			buf_printf(&buf, "0x%08x\t%s\t%s\tEXPORT_SYMBOL%s\t%s\n",
+				   sym->crc, sym->name, mod->name,
+				   sym->is_gpl_only ? "_GPL" : "",
+				   sym->namespace ?: "");
+		}
+	}
+	write_buf(&buf, fname);
+	free(buf.p);
+}
+
+static void write_namespace_deps_files(const char *fname)
+{
+	struct module *mod;
+	struct namespace_list *ns;
+	struct buffer ns_deps_buf = {};
+
+	list_for_each_entry(mod, &modules, list) {
+
+		if (mod->from_dump || list_empty(&mod->missing_namespaces))
+			continue;
+
+		buf_printf(&ns_deps_buf, "%s.ko:", mod->name);
+
+		list_for_each_entry(ns, &mod->missing_namespaces, list)
+			buf_printf(&ns_deps_buf, " %s", ns->namespace);
+
+		buf_printf(&ns_deps_buf, "\n");
+	}
+
+	write_if_changed(&ns_deps_buf, fname);
+	free(ns_deps_buf.p);
+}
+
+struct dump_list {
+	struct list_head list;
+	const char *file;
+};
+
+int main(int argc, char **argv)
+{
+	struct module *mod;
+	char *missing_namespace_deps = NULL;
+	char *dump_write = NULL, *files_source = NULL;
+	int opt;
+	LIST_HEAD(dump_lists);
+	struct dump_list *dl, *dl2;
+
+	while ((opt = getopt(argc, argv, "ei:mnT:o:awENd:")) != -1) {
+		switch (opt) {
+		case 'e':
+			external_module = true;
+			break;
+		case 'i':
+			dl = NOFAIL(malloc(sizeof(*dl)));
+			dl->file = optarg;
+			list_add_tail(&dl->list, &dump_lists);
+			break;
+		case 'm':
+			modversions = true;
+			break;
+		case 'n':
+			ignore_missing_files = true;
+			break;
+		case 'o':
+			dump_write = optarg;
+			break;
+		case 'a':
+			all_versions = true;
+			break;
+		case 'T':
+			files_source = optarg;
+			break;
+		case 'w':
+			warn_unresolved = true;
+			break;
+		case 'E':
+			sec_mismatch_warn_only = false;
+			break;
+		case 'N':
+			allow_missing_ns_imports = true;
+			break;
+		case 'd':
+			missing_namespace_deps = optarg;
+			break;
+		default:
+			exit(1);
+		}
+	}
+
+	list_for_each_entry_safe(dl, dl2, &dump_lists, list) {
+		read_dump(dl->file);
+		list_del(&dl->list);
+		free(dl);
+	}
+
+	while (optind < argc)
+		read_symbols(argv[optind++]);
+
+	if (files_source)
+		read_symbols_from_files(files_source);
+
+	list_for_each_entry(mod, &modules, list) {
+		if (mod->from_dump)
+			continue;
+
+		if (mod->is_vmlinux)
+			write_vmlinux_export_c_file(mod);
+		else
+			write_mod_c_file(mod);
+	}
+
+	if (missing_namespace_deps)
+		write_namespace_deps_files(missing_namespace_deps);
+
+	if (dump_write)
+		write_dump(dump_write);
+	if (sec_mismatch_count && !sec_mismatch_warn_only)
+		error("Section mismatches detected.\n"
+		      "Set CONFIG_SECTION_MISMATCH_WARN_ONLY=y to allow them.\n");
+
+	if (nr_unresolved > MAX_UNRESOLVED_REPORTS)
+		warn("suppressed %u unresolved symbol warnings because there were too many)\n",
+		     nr_unresolved - MAX_UNRESOLVED_REPORTS);
+
+	return error_occurred ? 1 : 0;
+}