[PATCH v2 04/14] ftrace: Use an opaque type for functions not callable from C

From: Sami Tolvanen
Date: Mon Aug 23 2021 - 13:13:39 EST


With CONFIG_CFI_CLANG, the compiler changes function references to point
to the CFI jump table. As ftrace_call, ftrace_regs_call, and mcount_call
are not called from C, use DECLARE_ASM_FUNC_SYMBOL to declare them.

Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
---
include/linux/ftrace.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index a69f363b61bf..6fdfbcc14608 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -578,9 +578,10 @@ extern void ftrace_replace_code(int enable);
extern int ftrace_update_ftrace_func(ftrace_func_t func);
extern void ftrace_caller(void);
extern void ftrace_regs_caller(void);
-extern void ftrace_call(void);
-extern void ftrace_regs_call(void);
-extern void mcount_call(void);
+
+DECLARE_ASM_FUNC_SYMBOL(ftrace_call);
+DECLARE_ASM_FUNC_SYMBOL(ftrace_regs_call);
+DECLARE_ASM_FUNC_SYMBOL(mcount_call);

void ftrace_modify_all_code(int command);

--
2.33.0.rc2.250.ged5fa647cd-goog