Re: [for-next][PATCH 05/30] arm64: function_graph: Remove use of FTRACE_NOTRACE_DEPTH

[Steven Rostedt]

On Wed, 05 Dec 2018 18:47:54 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> From: "Steven Rostedt (VMware)" <rostedt@xxxxxxxxxxx>
> 
> Functions in the set_graph_notrace no longer subtract FTRACE_NOTRACE_DEPTH
> from curr_ret_stack, as that is now implemented via the trace_recursion
> flags. Access to curr_ret_stack no longer needs to worry about checking for
> this. curr_ret_stack is still initialized to -1, when there's not a shadow
> stack allocated.
> 
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>

I haven't pushed this to Linux next yet. I tested the entire tree as
well as crossed compiled it against arm64.

Can you give me an ack for this patch?

Thanks!

-- Steve

> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Reviewed-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
> Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> ---
>  arch/arm64/kernel/stacktrace.c | 3 ---
>  1 file changed, 3 deletions(-)
> 
> diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
> index 4989f7ea1e59..7723dadf25be 100644
> --- a/arch/arm64/kernel/stacktrace.c
> +++ b/arch/arm64/kernel/stacktrace.c
> @@ -61,9 +61,6 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame)
>  			(frame->pc == (unsigned long)return_to_handler)) {
>  		if (WARN_ON_ONCE(frame->graph == -1))
>  			return -EINVAL;
> -		if (frame->graph < -1)
> -			frame->graph += FTRACE_NOTRACE_DEPTH;
> -
>  		/*
>  		 * This is a case where function graph tracer has
>  		 * modified a return address (LR) in a stack frame