From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1D11FC83F25 for ; Mon, 21 Jul 2025 12:19:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=6sN8MJ1ihkVUzlJVBBvhi0gCkpUEIkqNwpczuIfgkWY=; b=AbQFtuEYX9tJ/sPugl9pDVob5w ARbFeoiIjSw0ab7eavsYDBE8e6RTVVtCmKzoTBZeRdXg5GQZ2Y1bzlINS616bAr69GEDXSXEIXSFL xRmonFlDEPyuhm1Qo4Z4pQm5YxSLIZdK2MZdaLBsr5zQ2m9E5AL89QItEsL6yhJt3pG3MpgByRDpM Ny2D2I8o/KjNvB5+M1ud3xCc9r/+brUa5Ghfc0X4PSnaonrV74kXVODFlkm1MtbjN3oChILys1FL6 XUD0mxXy1LSNZzNqf9mwK6pYmqEpuxF2B8DuZ2atCfJ6EmzeNzd0PPERRdPmQ9nz+WNhO0tm4vo7Y 0dgO5iIw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1udpUm-0000000HEyR-0TLh; Mon, 21 Jul 2025 12:19:52 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1udo8A-0000000H09d-0y8T for linux-arm-kernel@lists.infradead.org; Mon, 21 Jul 2025 10:52:27 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5E000153B; Mon, 21 Jul 2025 03:52:17 -0700 (PDT) Received: from J2N7QTR9R3 (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4D72B3F59E; Mon, 21 Jul 2025 03:52:21 -0700 (PDT) Date: Mon, 21 Jul 2025 11:52:16 +0100 From: Mark Rutland To: Yeoreum Yun Cc: catalin.marinas@arm.com, will@kernel.org, broonie@kernel.org, oliver.upton@linux.dev, ardb@kernel.org, frederic@kernel.org, james.morse@arm.com, joey.gouly@arm.com, scott@os.amperecomputing.com, maz@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 3/7] arm64/Kconfig: add LSUI Kconfig Message-ID: References: <20250721083618.2743569-1-yeoreum.yun@arm.com> <20250721083618.2743569-4-yeoreum.yun@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250721083618.2743569-4-yeoreum.yun@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250721_035226_317218_A20FB9C3 X-CRM114-Status: GOOD ( 18.19 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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/ > > Signed-off-by: Yeoreum Yun > --- > 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} > >