Re: [PATCH 11/17] x86/kprobes: Make trampoline_handler global and visible

[Masami Hiramatsu]

On Thu, 21 Mar 2019 15:00:03 -0700
Andi Kleen <andi@xxxxxxxxxxxxxx> wrote:

> From: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> 
> This function is referenced from assembler, so in LTO
> it needs to be global and visible to not be optimized away.
> 

I got it.

Acked-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>

Andi, out of curiousity, that is not only for x86, but
does all arch have to care it?

Thank you,

> Cc: mhiramat@xxxxxxxxxx
> Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
> ---
>  arch/x86/kernel/kprobes/core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
> index 31ab91c9c4e9..1309a4eb3119 100644
> --- a/arch/x86/kernel/kprobes/core.c
> +++ b/arch/x86/kernel/kprobes/core.c
> @@ -752,7 +752,7 @@ STACK_FRAME_NON_STANDARD(kretprobe_trampoline);
>  /*
>   * Called from kretprobe_trampoline
>   */
> -static __used void *trampoline_handler(struct pt_regs *regs)
> +__used __visible void *trampoline_handler(struct pt_regs *regs)
>  {
>  	struct kretprobe_instance *ri = NULL;
>  	struct hlist_head *head, empty_rp;
> -- 
> 2.20.1
> 


-- 
Masami Hiramatsu <mhiramat@xxxxxxxxxx>