[PATCH 05/11] objtool: Convert VALIDATE_UNRET_BEGIN to ANNOTATE

From: Peter Zijlstra
Date: Mon Dec 04 2023 - 04:39:58 EST



Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
include/linux/objtool.h | 9 +++------
include/linux/objtool_types.h | 1 +
tools/include/linux/objtool_types.h | 1 +
tools/objtool/check.c | 28 +++++-----------------------
4 files changed, 10 insertions(+), 29 deletions(-)

--- a/include/linux/objtool.h
+++ b/include/linux/objtool.h
@@ -128,15 +128,12 @@
* NOTE: The macro must be used at the beginning of a global symbol, otherwise
* it will be ignored.
*/
-.macro VALIDATE_UNRET_BEGIN
#if defined(CONFIG_NOINSTR_VALIDATION) && \
(defined(CONFIG_CPU_UNRET_ENTRY) || defined(CONFIG_CPU_SRSO))
-.Lhere_\@:
- .pushsection .discard.validate_unret
- .long .Lhere_\@ - .
- .popsection
+#define VALIDATE_UNRET_BEGIN ANNOTATE type=ANNOTYPE_UNRET_BEGIN
+#else
+#define VALIDATE_UNRET_BEGIN
#endif
-.endm

.macro REACHABLE
.Lhere_\@:
--- a/include/linux/objtool_types.h
+++ b/include/linux/objtool_types.h
@@ -61,5 +61,6 @@ struct unwind_hint {
#define ANNOTYPE_RETPOLINE_SAFE 2
#define ANNOTYPE_INSTR_BEGIN 3
#define ANNOTYPE_INSTR_END 4
+#define ANNOTYPE_UNRET_BEGIN 5

#endif /* _LINUX_OBJTOOL_TYPES_H */
--- a/tools/include/linux/objtool_types.h
+++ b/tools/include/linux/objtool_types.h
@@ -61,5 +61,6 @@ struct unwind_hint {
#define ANNOTYPE_RETPOLINE_SAFE 2
#define ANNOTYPE_INSTR_BEGIN 3
#define ANNOTYPE_INSTR_END 4
+#define ANNOTYPE_UNRET_BEGIN 5

#endif /* _LINUX_OBJTOOL_TYPES_H */
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2385,33 +2385,15 @@ static int __annotate_instr(int type, st
return 0;
}

-static int read_validate_unret_hints(struct objtool_file *file)
+static int __annotate_unret(int type, struct instruction *insn)
{
- struct section *rsec;
- struct instruction *insn;
- struct reloc *reloc;
-
- rsec = find_section_by_name(file->elf, ".rela.discard.validate_unret");
- if (!rsec)
+ if (type != ANNOTYPE_UNRET_BEGIN)
return 0;

- for_each_reloc(rsec, reloc) {
- if (reloc->sym->type != STT_SECTION) {
- WARN("unexpected relocation symbol type in %s", rsec->name);
- return -1;
- }
-
- insn = find_insn(file, reloc->sym->sec, reloc_addend(reloc));
- if (!insn) {
- WARN("bad .discard.instr_end entry");
- return -1;
- }
- insn->unret = 1;
- }
-
+ insn->unret = 1;
return 0;
-}

+}

static int read_intra_function_calls(struct objtool_file *file)
{
@@ -2629,7 +2611,7 @@ static int decode_sections(struct objtoo
if (ret)
return ret;

- ret = read_validate_unret_hints(file);
+ ret = read_annotate(file, __annotate_unret);
if (ret)
return ret;