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 8C39BC624D0 for ; Wed, 2 Sep 2026 11:32:56 +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:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=vuK7MrqEgHOT8EJAWsNn0D1m+Ynm/cCoqkC8oHXW+wE=; b=DKztvzBfnvYO1zZdKETyFwuTOu 6HjM9Z2yyboIRSAUMrQcNot7Gcpczr4/1Ezl6HcfEpyQer6HuWib/sV0iX9TAMG9VrozyrWTIAGAU Ay/CTtb7zQpgkE0JNFj8+BqivG5AkiyEcLEP/VNX4a6yogEeMQh59iPtY77S8T1VJZbRNN9IjLkHs /0BFkPNirzaa6k6MbcpXh9S6moljHtH5B8dv1imF+l25Zl+0yvxB+1s5+8Z5322PdHhZYr+Le8Vkj Hl7RowyuibjnzALwybpCnYuJo0Kv1+lJZ78qhexnjAYKsysmLSGdya93xCm2oM3e1oLELM6SbWOuK l9RcwyUQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x1jCv-0000000EWCr-33R5; Wed, 02 Sep 2026 11:32:45 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1x1jCt-0000000EWBW-1A1C for linux-arm-kernel@lists.infradead.org; Wed, 02 Sep 2026 11:32:44 +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 A86D41682; Wed, 2 Sep 2026 04:32:37 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 94A1C3F85F; Wed, 2 Sep 2026 04:32:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1788348761; bh=nHgWksvphyJGNfsY7gau2yjC23W5OgGE2LHLUBpMccg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JHzy/ah66GWJPkV1JYzhz9I56rhgAWoqBnzHtd9AuAYNAv16FVAb9cS26p1tUWt5i RlRnxe9h9zT60JcJYRJzAPhPp+wTBEVz4VYlEwIeBACC0J/AGX+c/H04auZ2FU09Ir gTlj1r5UivyrZpskAMlhVgozw6gzu+5QvIHj28j4= From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, james.morse@arm.com, mark.rutland@arm.com, maz@kernel.org, will@kernel.org Subject: [PATCH 1/2] arm64: mte-kasan: Use IS_ENABLED() rather than ALTERNATIVE() 'cfg' parameter Date: Wed, 2 Sep 2026 12:32:31 +0100 Message-Id: <20260902113232.314831-2-mark.rutland@arm.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20260902113232.314831-1-mark.rutland@arm.com> References: <20260902113232.314831-1-mark.rutland@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260902_043243_360735_FDAA1BBC X-CRM114-Status: GOOD ( 13.20 ) 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 The ALTERNATIVE() macro accepts an optional 'cfg' parameter, which accepts a CONFIG_* symbol. Where a CONFIG_* symbol is provided, but is not selected, the ALTERNATIVE() macro will expand to nothing. It would be nicer overall to remove the 'cfg' parameter and to have an explicit check for 'cfg' outside of the asm() block. This is clearer to a reader, and permits the compiler to elide the asm() block when 'cfg' is not selected. In the mte-kasan code, replace the usage of the 'cfg' parameter with an explicit IS_ENABLED() check. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: James Morse Cc: Marc Zyngier Cc: Will Deacon --- arch/arm64/include/asm/mte-kasan.h | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/mte-kasan.h b/arch/arm64/include/asm/mte-kasan.h index 3521392719189..de910f1c19e1b 100644 --- a/arch/arm64/include/asm/mte-kasan.h +++ b/arch/arm64/include/asm/mte-kasan.h @@ -53,14 +53,16 @@ static inline bool system_uses_mte_async_or_asymm_mode(void) */ static inline void mte_disable_tco(void) { - asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(0), - ARM64_MTE, CONFIG_KASAN_HW_TAGS)); + if (!IS_ENABLED(CONFIG_KASAN_HW_TAGS)) + return; + asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(0), ARM64_MTE)); } static inline void mte_enable_tco(void) { - asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(1), - ARM64_MTE, CONFIG_KASAN_HW_TAGS)); + if (!IS_ENABLED(CONFIG_KASAN_HW_TAGS)) + return; + asm volatile(ALTERNATIVE("nop", SET_PSTATE_TCO(1), ARM64_MTE)); } /* -- 2.30.2