modpost: remove useless export_from_sec()

With commit 1743694eb235 ("modpost: stop symbol preloading for
modversion CRC") applied, now export_from_sec() is useless.

handle_symbol() is called for every symbol in the ELF.

When 'symname' does not start with "__ksymtab", export_from_sec() is
called, and the returned value is stored in 'export'.

It is used in the last part of handle_symbol():

    if (strstarts(symname, "__ksymtab_")) {
            name = symname + strlen("__ksymtab_");
            sym_add_exported(name, mod, export);
    }

'export' is used only when 'symname' starts with "__ksymtab_".

So, the value returned by export_from_sec() is never used.

Remove useless export_from_sec(). This makes further cleanups possible.

I put the temporary code:

    export = export_unknown;

Otherwise, I would get the compiler warning:

    warning: 'export' may be used uninitialized in this function [-Wmaybe-uninitialized]

This is apparently false positive because

    if (strstarts(symname, "__ksymtab_")

... is a stronger condition than:

    if (strstarts(symname, "__ksymtab")

Anyway, this part will be cleaned up by the next commit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index ed9d056..eebb326 100644 (file)
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -369,16 +369,6 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
                return export_unknown;
 }
 
-static enum export export_from_sec(struct elf_info *elf, unsigned int sec)
-{
-       if (sec == elf->export_sec)
-               return export_plain;
-       else if (sec == elf->export_gpl_sec)
-               return export_gpl;
-       else
-               return export_unknown;
-}
-
 static const char *namespace_from_kstrtabns(const struct elf_info *info,
                                            const Elf_Sym *sym)
 {
@@ -576,10 +566,7 @@ static int parse_elf(struct elf_info *info, const char *filename)
                                fatal("%s has NOBITS .modinfo\n", filename);
                        info->modinfo = (void *)hdr + sechdrs[i].sh_offset;
                        info->modinfo_len = sechdrs[i].sh_size;
-               } else if (strcmp(secname, "__ksymtab") == 0)
-                       info->export_sec = i;
-               else if (strcmp(secname, "__ksymtab_gpl") == 0)
-                       info->export_gpl_sec = i;
+               }
 
                if (sechdrs[i].sh_type == SHT_SYMTAB) {
                        unsigned int sh_link_idx;
@@ -703,7 +690,7 @@ static void handle_symbol(struct module *mod, struct elf_info *info,
        if (strstarts(symname, "__ksymtab"))
                export = export_from_secname(info, get_secindex(info, sym));
        else
-               export = export_from_sec(info, get_secindex(info, sym));
+               export = export_unknown;
 
        switch (sym->st_shndx) {
        case SHN_COMMON:

diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 0c47ff9..0a940fd 100644 (file)
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -138,8 +138,6 @@ struct elf_info {
        Elf_Shdr     *sechdrs;
        Elf_Sym      *symtab_start;
        Elf_Sym      *symtab_stop;
-       Elf_Section  export_sec;
-       Elf_Section  export_gpl_sec;
        char         *strtab;
        char         *modinfo;
        unsigned int modinfo_len;