Re: [PATCH 06/21] x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub

[Steven Rostedt]

On Thu, 14 Jan 2021 13:40:02 -0600
Josh Poimboeuf <jpoimboe@xxxxxxxxxx> wrote:

> Prevent an unreachable objtool warning after the sibling call detection
> gets improved.  ftrace_stub() is basically a function, annotate it as
> such.
> 
> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>

Acked-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>

-- Steve

> Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
> ---
>  arch/x86/kernel/ftrace_64.S | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S
> index 0d54099c2a3a..58d125ed9d1a 100644
> --- a/arch/x86/kernel/ftrace_64.S
> +++ b/arch/x86/kernel/ftrace_64.S
> @@ -184,6 +184,7 @@ SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL)
>   * It is also used to copy the retq for trampolines.
>   */
>  SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK)
> +	UNWIND_HINT_FUNC
>  	retq
>  SYM_FUNC_END(ftrace_epilogue)
>