Re: [PATCH v4 3/7] arm64/Kconfig: add LSUI Kconfig
From: Mark Rutland <mark.rutland@arm.com>
Date: 2025-07-21 10:52:23
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On Mon, Jul 21, 2025 at 09:36:14AM +0100, 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 LUSI uses
Nit: s/LUSI/LSUI/
indiviual `.arch_extension` entries.
Nit: s/indiviual/individual/
quoted hunk ↗ jump to hunk
Signed-off-by: Yeoreum Yun <redacted> --- arch/arm64/Kconfig | 9 +++++++++ 1 file changed, 9 insertions(+)diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 393d71124f5d..c0beb44ed5b8 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig@@ -2238,6 +2238,15 @@ config ARM64_GCS endmenu # "v9.4 architectural features" +config AS_HAS_LSUI + def_bool $(as-instr,.arch_extension lsui) + help + Unprivileged Load Store is an extension to introduce unprivileged + variants of load and store instructions so that clearing PSTATE.PAN + is never required in privileged mode. + This feature is available with clang version 20 and later and not yet + supported by gcc.
I don't think we need to describe the feature in detail for the AS_HAS_* config symbol; I think all we need to say is: Supported by LLVM 20 and later, not yet supported by GNU AS. Otherwise this looks fine. Mark.
+
config ARM64_SVE
bool "ARM Scalable Vector Extension support"
default y
--
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}