Re: [PATCH v11 RESEND 4/9] arm64: Kconfig: Detect toolchain support for LSUI

Will Deacon
2026-01-19T15:50:51Z

On Sun, Dec 14, 2025 at 11:22:43AM +0000, Yeoreum Yun wrote:
> Since Armv9.6, FEAT_LSUI supplies the load/store instructions for
> previleged level to access to access user memory without clearing
> PSTATE.PAN bit.
> It's enough to add CONFIG_AS_HAS_LSUI only because the code for LSUI uses
> individual `.arch_extension` entries.
>
> Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> ---
> arch/arm64/Kconfig | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 93173f0a09c7..36e87a1a1b5c 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -2227,6 +2227,11 @@ config ARM64_GCS
>
> endmenu # "ARMv9.4 architectural features"
>
> +config AS_HAS_LSUI
> + def_bool $(as-instr,.arch_extension lsui)
> + help
> + Supported by LLVM 20+ and binutils 2.45+.

This is an internal Kconfig variable so please drop the help text.

Will