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Subject: Re: [RFC 4/6] arm64: assembler: Add macro to annotate asm function
 having non standard stack-frame.
To:     Raphael Gault <raphael.gault@arm.com>,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org
Cc:     jpoimboe@redhat.com, peterz@infradead.org, catalin.marinas@arm.com,
        will.deacon@arm.com
References: <20190409135243.12424-1-raphael.gault@arm.com>
 <20190409135243.12424-5-raphael.gault@arm.com>
From:   Julien Thierry <julien.thierry@arm.com>
Message-ID: <c14b8e06-3916-9936-0093-6a8935019d26@arm.com>
Date:   Wed, 24 Apr 2019 11:44:26 +0100
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Hi Raphaël,

On 09/04/2019 14:52, Raphael Gault wrote:
> Signed-off-by: Raphael Gault <raphael.gault@arm.com>

Even there is not much to say, we include a commit message to explain
what the patch does and/or why we want it.

> ---
>  arch/arm64/include/asm/assembler.h | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
> index 4feb6119c3c9..636a07a7eb76 100644
> --- a/arch/arm64/include/asm/assembler.h
> +++ b/arch/arm64/include/asm/assembler.h
> @@ -748,4 +748,22 @@ USER(\label, ic	ivau, \tmp2)			// invalidate I line PoU
>  .Lyield_out_\@ :
>  	.endm
>  
> +
> +#ifdef	CONFIG_STACK_VALIDATION
> +	/*
> +	 * This macro is the arm64 assembler equivalent of the
> +	 * macro STACK_FRAME_NON_STANDARD define at
> +	 * ~/include/linux/frame.h
> +	 */
> +	.macro	asm_stack_frame_non_standard	func
> +	.pushsection ".discard.func_stack_frame_non_standard"
> +	.8byte	\func
> +	.popsection
> +	.endm
> +#else
> +	.macro	asm_stack_frame_non_standard	func
> +	.endm
> +#endif
> +
> +

This can be simplified as:

	.macro asm_stack_frame_non_standard func
#ifdef CONFIG_STACK_VALIDATION
	[...]
#endif
	.endm

>  #endif	/* __ASM_ASSEMBLER_H */
> 

Cheers,

-- 
Julien Thierry