[PATCH 05/48] objtool: Move mark_rodata() to elf.c

Josh Poimboeuf
2026-04-23T04:04:26Z

Move the sec->rodata marking from check.c to elf.c so it's set during
ELF reading rather than during the check pipeline. This makes the
rodata flag available to all objtool users, including klp-diff which
reads ELF files directly without running check().

Add an is_rodata_sec() helper to elf.h for consistency with
is_text_sec() and is_string_sec().

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
---
tools/objtool/check.c | 11 +++--------
tools/objtool/elf.c | 13 +++++++++++++
tools/objtool/include/objtool/elf.h | 5 +++++
3 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 9b11cf3193b9..5722d4568401 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2566,7 +2566,6 @@ static int classify_symbols(struct objtool_file *file)
static void mark_rodata(struct objtool_file *file)
{
struct section *sec;
- bool found = false;

/*
* Search for the following rodata sections, each of which can
@@ -2579,15 +2578,11 @@ static void mark_rodata(struct objtool_file *file)
* .rodata.str1.* sections are ignored; they don't contain jump tables.
*/
for_each_sec(file->elf, sec) {
- if ((!strncmp(sec->name, ".rodata", 7) &&
- !strstr(sec->name, ".str1.")) ||
- !strncmp(sec->name, ".data.rel.ro", 12)) {
- sec->rodata = true;
- found = true;
+ if (is_rodata_sec(sec)) {
+ file->rodata = true;
+ return;
}
}
-
- file->rodata = found;
}

static void mark_holes(struct objtool_file *file)
diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c
index f3df2bde119f..ac9da81a7a2f 100644
--- a/tools/objtool/elf.c
+++ b/tools/objtool/elf.c
@@ -1172,6 +1172,17 @@ static int read_relocs(struct elf *elf)
return 0;
}

+static void mark_rodata(struct elf *elf)
+{
+ struct section *sec;
+
+ for_each_sec(elf, sec) {
+ if ((strstarts(sec->name, ".rodata") && !strstr(sec->name, ".str1.")) ||
+ strstarts(sec->name, ".data.rel.ro"))
+ sec->rodata = true;
+ }
+}
+
struct elf *elf_open_read(const char *name, int flags)
{
struct elf *elf;
@@ -1222,6 +1233,8 @@ struct elf *elf_open_read(const char *name, int flags)
if (read_sections(elf))
goto err;

+ mark_rodata(elf);
+
if (read_symbols(elf))
goto err;

diff --git a/tools/objtool/include/objtool/elf.h b/tools/objtool/include/objtool/elf.h
index 25573e5af76e..c61bd57767f9 100644
--- a/tools/objtool/include/objtool/elf.h
+++ b/tools/objtool/include/objtool/elf.h
@@ -296,6 +296,11 @@ static inline bool is_text_sec(struct section *sec)
return sec->sh.sh_flags & SHF_EXECINSTR;
}

+static inline bool is_rodata_sec(struct section *sec)
+{
+ return sec->rodata;
+}
+
static inline bool sec_changed(struct section *sec)
{
return sec->_changed;
--
2.53.0