x86/ftrace: Mark ftrace_modify_code_direct() __ref

... because it calls the .init.text function text_poke_early(). That is
ok because it does call that function early, during boot.

Fixes: 9706f7c ("x86/ftrace: Use text_poke()")
Suggested-by: Peter Zijlstra <[email protected]>
Signed-off-by: Borislav Petkov <[email protected]>
Acked-by: Steven Rostedt (VMware) <[email protected]>
Cc: Alexei Starovoitov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Daniel Bristot de Oliveira <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

Author: suryasaimadhu

arch/x86/kernel/ftrace.c

@@ -99,7 +99,12 @@ static int ftrace_verify_code(unsigned long ip, const char *old_code)
 	return 0;
 }
 
-static int
+/*
+ * Marked __ref because it calls text_poke_early() which is .init.text. That is
+ * ok because that call will happen early, during boot, when .init sections are
+ * still present.
+ */
+static int __ref
 ftrace_modify_code_direct(unsigned long ip, const char *old_code,
 			  const char *new_code)
 {