Re: [PATCH v2 2/2] arm64: insn: drop NOP from steppable hint list

Mark Rutland
2026-02-17T16:57:27Z

On Tue, Feb 17, 2026 at 07:08:55PM +0530, Khaja Hussain Shaik Khaji wrote:
> NOP is already handled via instruction emulation and does not require
> single-stepping. Drop it from aarch64_insn_is_steppable_hint().
>
> Signed-off-by: Khaja Hussain Shaik Khaji <khaja.khaji@oss.qualcomm.com>
> ---
> arch/arm64/include/asm/insn.h | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
> index e1d30ba99d01..9429f76906e0 100644
> --- a/arch/arm64/include/asm/insn.h
> +++ b/arch/arm64/include/asm/insn.h
> @@ -456,7 +456,6 @@ static __always_inline bool aarch64_insn_is_steppable_hint(u32 insn)
> case AARCH64_INSN_HINT_BTIC:
> case AARCH64_INSN_HINT_BTIJ:
> case AARCH64_INSN_HINT_BTIJC:
> - case AARCH64_INSN_HINT_NOP:
> return true;
> default:
> return false;

The intent is that aarch64_insn_is_steppable_hint() says whether an
instruction is safe to step, not whether it *must* be stepped. I think
we can leave NOP here unless this is causing some functional problem?

Mark.