[PATCH -tip v11 17/27] objtool: Add frame-pointer-specific function ignore

Masami Hiramatsu
2021-09-14T14:41:13Z

From: Josh Poimboeuf <jpoimboe@redhat.com>

Add a CONFIG_FRAME_POINTER-specific version of
STACK_FRAME_NON_STANDARD() for the case where a function is
intentionally missing frame pointer setup, but otherwise needs
objtool/ORC coverage when frame pointers are disabled.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
---
Changes in v10:
- Fixes error in CONFIG_STACK_VALIDATION=n case.
---
include/linux/objtool.h | 12 ++++++++++++
tools/include/linux/objtool.h | 12 ++++++++++++
2 files changed, 24 insertions(+)

diff --git a/include/linux/objtool.h b/include/linux/objtool.h
index 7e72d975cb76..aca52db2f3f3 100644
--- a/include/linux/objtool.h
+++ b/include/linux/objtool.h
@@ -66,6 +66,17 @@ struct unwind_hint {
static void __used __section(".discard.func_stack_frame_non_standard") \
*__func_stack_frame_non_standard_##func = func

+/*
+ * STACK_FRAME_NON_STANDARD_FP() is a frame-pointer-specific function ignore
+ * for the case where a function is intentionally missing frame pointer setup,
+ * but otherwise needs objtool/ORC coverage when frame pointers are disabled.
+ */
+#ifdef CONFIG_FRAME_POINTER
+#define STACK_FRAME_NON_STANDARD_FP(func) STACK_FRAME_NON_STANDARD(func)
+#else
+#define STACK_FRAME_NON_STANDARD_FP(func)
+#endif
+
#else /* __ASSEMBLY__ */

/*
@@ -127,6 +138,7 @@ struct unwind_hint {
#define UNWIND_HINT(sp_reg, sp_offset, type, end) \
"\n\t"
#define STACK_FRAME_NON_STANDARD(func)
+#define STACK_FRAME_NON_STANDARD_FP(func)
#else
#define ANNOTATE_INTRA_FUNCTION_CALL
.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0
diff --git a/tools/include/linux/objtool.h b/tools/include/linux/objtool.h
index 7e72d975cb76..aca52db2f3f3 100644
--- a/tools/include/linux/objtool.h
+++ b/tools/include/linux/objtool.h
@@ -66,6 +66,17 @@ struct unwind_hint {
static void __used __section(".discard.func_stack_frame_non_standard") \
*__func_stack_frame_non_standard_##func = func

+/*
+ * STACK_FRAME_NON_STANDARD_FP() is a frame-pointer-specific function ignore
+ * for the case where a function is intentionally missing frame pointer setup,
+ * but otherwise needs objtool/ORC coverage when frame pointers are disabled.
+ */
+#ifdef CONFIG_FRAME_POINTER
+#define STACK_FRAME_NON_STANDARD_FP(func) STACK_FRAME_NON_STANDARD(func)
+#else
+#define STACK_FRAME_NON_STANDARD_FP(func)
+#endif
+
#else /* __ASSEMBLY__ */

/*
@@ -127,6 +138,7 @@ struct unwind_hint {
#define UNWIND_HINT(sp_reg, sp_offset, type, end) \
"\n\t"
#define STACK_FRAME_NON_STANDARD(func)
+#define STACK_FRAME_NON_STANDARD_FP(func)
#else
#define ANNOTATE_INTRA_FUNCTION_CALL
.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0