Re: [PATCH 1/2] objtool: Add frame-pointer-specific function ignore

From: Masami Hiramatsu <mhiramat@kernel.org>
To: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>, X86 ML <x86@kernel.org>,
	Daniel Xu <dxu@dxuuu.xyz>,
	linux-kernel@vger.kernel.org, bpf@vger.kernel.org,
	kuba@kernel.org, mingo@redhat.com, ast@kernel.org,
	Thomas Gleixner <tglx@linutronix.de>,
	Borislav Petkov <bp@alien8.de>,
	Peter Zijlstra <peterz@infradead.org>,
	kernel-team@fb.com, yhs@fb.com, linux-ia64@vger.kernel.org,
	Abhishek Sagar <sagar.abhishek@gmail.com>,
	Andrii Nakryiko <andrii.nakryiko@gmail.com>
Subject: Re: [PATCH 1/2] objtool: Add frame-pointer-specific function ignore
Date: Sun, 11 Jul 2021 10:16:33 +0900	[thread overview]
Message-ID: <20210711101633.eaceff78742984c641993ced@kernel.org> (raw)
In-Reply-To: <20210710192433.x5cgjsq2ksvaqnss@treble>

On Sat, 10 Jul 2021 12:24:33 -0700
Josh Poimboeuf <jpoimboe@redhat.com> wrote:

> Add a CONFIG_FRAME_POINTER-specific version of
> STACK_FRAME_NON_STANDARD() for the case where a function is
> intentionally missing frame pointer setup, but otherwise needs
> objtool/ORC coverage when frame pointers are disabled.

Looks good to me.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>

Thanks!

> 
> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
> ---
>  include/linux/objtool.h       | 11 +++++++++++
>  tools/include/linux/objtool.h | 11 +++++++++++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/include/linux/objtool.h b/include/linux/objtool.h
> index 7e72d975cb76..c9575ed91052 100644
> --- a/include/linux/objtool.h
> +++ b/include/linux/objtool.h
> @@ -66,6 +66,17 @@ struct unwind_hint {
>  	static void __used __section(".discard.func_stack_frame_non_standard") \
>  		*__func_stack_frame_non_standard_##func = func
>  
> +/*
> + * STACK_FRAME_NON_STANDARD_FP() is a frame-pointer-specific function ignore
> + * for the case where a function is intentionally missing frame pointer setup,
> + * but otherwise needs objtool/ORC coverage when frame pointers are disabled.
> + */
> +#ifdef CONFIG_FRAME_POINTER
> +#define STACK_FRAME_NON_STANDARD_FP(func) STACK_FRAME_NON_STANDARD(func)
> +#else
> +#define STACK_FRAME_NON_STANDARD_FP(func)
> +#endif
> +
>  #else /* __ASSEMBLY__ */
>  
>  /*
> diff --git a/tools/include/linux/objtool.h b/tools/include/linux/objtool.h
> index 7e72d975cb76..c9575ed91052 100644
> --- a/tools/include/linux/objtool.h
> +++ b/tools/include/linux/objtool.h
> @@ -66,6 +66,17 @@ struct unwind_hint {
>  	static void __used __section(".discard.func_stack_frame_non_standard") \
>  		*__func_stack_frame_non_standard_##func = func
>  
> +/*
> + * STACK_FRAME_NON_STANDARD_FP() is a frame-pointer-specific function ignore
> + * for the case where a function is intentionally missing frame pointer setup,
> + * but otherwise needs objtool/ORC coverage when frame pointers are disabled.
> + */
> +#ifdef CONFIG_FRAME_POINTER
> +#define STACK_FRAME_NON_STANDARD_FP(func) STACK_FRAME_NON_STANDARD(func)
> +#else
> +#define STACK_FRAME_NON_STANDARD_FP(func)
> +#endif
> +
>  #else /* __ASSEMBLY__ */
>  
>  /*
> -- 
> 2.31.1
> 

-- 
Masami Hiramatsu <mhiramat@kernel.org>