Re: [PATCH 4/8] arm64: insn: Add helpers for adrp offsets

From: Marc Zyngier
Date: Thu Aug 18 2016 - 10:47:53 EST


Hi Suzuki,

On 18/08/16 14:10, Suzuki K Poulose wrote:
> Adds helpers for decoding/encoding the PC relative addresses for adrp.
> This will be used for handling dynamic patching of 'adrp' instructions
> in alternative code patching.
>
> Cc: Mark Rutland <mark.rutland@xxxxxxx>
> Cc: Will Deacon <will.deacon@xxxxxxx>
> Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> ---
> arch/arm64/include/asm/insn.h | 4 ++++
> arch/arm64/kernel/insn.c | 13 +++++++++++++
> 2 files changed, 17 insertions(+)
>
> diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
> index 1dbaa90..dffb0364 100644
> --- a/arch/arm64/include/asm/insn.h
> +++ b/arch/arm64/include/asm/insn.h
> @@ -247,6 +247,7 @@ static __always_inline u32 aarch64_insn_get_##abbr##_value(void) \
> { return (val); }
>
> __AARCH64_INSN_FUNCS(adr_adrp, 0x1F000000, 0x10000000)
> +__AARCH64_INSN_FUNCS(adrp, 0x9F000000, 0x90000000)

I'm a bit bothered by this one. We end-up with both
aarch64_insn_is_adr_adrp() *and* aarch64_insn_is_adrp() (and their
respective getters).

How about dropping adr_adrp, and explicitly having adr and adrp? There
is only two users in the tree, so that should be easy to address.

Thanks,

M.
--
Jazz is not dead. It just smells funny...