[PATCH v3 5/5] arm64: Add HAVE_REGS_AND_STACK_ACCESS_API feature

[Will Deacon]

Hi David,

On Tue, Nov 18, 2014 at 06:32:55AM +0000, David Long wrote:
> From: "David A. Long" <dave.long at linaro.org>
> 
> Add HAVE_REGS_AND_STACK_ACCESS_API feature for arm64.

[...]

> diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h
> index d3e782a..24cc048 100644
> --- a/arch/arm64/include/asm/ptrace.h
> +++ b/arch/arm64/include/asm/ptrace.h
> @@ -111,6 +111,8 @@ struct pt_regs {
>  	u64 syscallno;
>  };
>  
> +#define MAX_REG_OFFSET (offsetof(struct pt_regs, orig_x0))

Is orig_x0 actually useful to this API? If not, we could instead operate on
the user_pt_regs structure, and define the maximum offset in terms of sizeof
that.

> +#define ARM_cpsr	pstate
> +#define ARM_pc		pc
> +#define ARM_sp		sp
> +#define ARM_lr		regs[30]
> +#define ARM_fp		regs[29]
> +#define ARM_x28		regs[28]
> +#define ARM_x27		regs[27]

[...]

I don't think we need these #defines.

Will