[PATCH v2 06/10] modpost: remove annoying namespace_from_kstrtabns()

From: Masahiro Yamada
Date: Tue Apr 05 2022 - 19:27:21 EST


There are two call sites for sym_update_namespace().

When the symbol has no namespace, s->namespace is set to NULL,
but the conversion from "" to NULL is done in two different places.

[1] read_symbols()

This gets the namespace from __kstrtabns_<symbol>. If the symbol has
no namespace, sym_get_data(info, sym) returns the empty string "".
namespace_from_kstrtabns() converts it to NULL before it is passed to
sym_update_namespace().

[2] read_dump()

This gets the namespace from the dump file, *.symvers. If the symbol
has no namespace, the 'namespace' is the empty string "", which is
directly passed into sym_update_namespace(). The conversion from
"" to NULL is done in sym_update_namespace().

namespace_from_kstrtabns() exists only for creating this inconsistency.

By removing it, sym_update_namespace() is consistently passed with ""
when the symbol has no namespace.

Signed-off-by: Masahiro Yamada <masahiroy@xxxxxxxxxx>
---

Changes in v2:
- new

scripts/mod/modpost.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index 2a202764ff48..522d5249d196 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -369,13 +369,6 @@ static enum export export_from_secname(struct elf_info *elf, unsigned int sec)
return export_unknown;
}

-static const char *namespace_from_kstrtabns(const struct elf_info *info,
- const Elf_Sym *sym)
-{
- const char *value = sym_get_data(info, sym);
- return value[0] ? value : NULL;
-}
-
static void sym_update_namespace(const char *symname, const char *namespace)
{
struct symbol *s = find_symbol(symname);
@@ -391,8 +384,7 @@ static void sym_update_namespace(const char *symname, const char *namespace)
}

free(s->namespace);
- s->namespace =
- namespace && namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
+ s->namespace = namespace[0] ? NOFAIL(strdup(namespace)) : NULL;
}

/**
@@ -2049,9 +2041,7 @@ static void read_symbols(const char *modname)
/* Apply symbol namespaces from __kstrtabns_<symbol> entries. */
if (strstarts(symname, "__kstrtabns_"))
sym_update_namespace(symname + strlen("__kstrtabns_"),
- namespace_from_kstrtabns(&info,
- sym));
-
+ sym_get_data(&info, sym));
if (strstarts(symname, "__crc_"))
handle_modversion(mod, &info, sym,
symname + strlen("__crc_"));
--
2.32.0