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 X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1CB9C35280 for ; Tue, 8 Oct 2019 16:19:05 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 91854206C2 for ; Tue, 8 Oct 2019 16:19:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="nRjk/W7P" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 91854206C2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=8NlDD6b2M30s9MhylNsyCOMy7lCK6txhw0HfGzM3mYQ=; b=nRjk/W7PfXP20A4QmYLEBXJKg Bfkgg+NjYCUUFIcCmnDw7Dbwsjtmp7xHU12mnzsJ8XtzFG18BqVg192AE5YMhaiG7f+9B+79+GrQ6 gvOkessjnNzhNXA2xrCV1RNtgaGdg/Q8GiFWILKPSCAZDGnYUvrdRT9fMt30sD0QX0H7Epv7JnHVv 6lwEgSWWbCdoxNxnrFTEHErtSuFzx/Zlx7bO/4Ym4BHJ+TWe/CxBc2ElKN+Wh/cYvtsTc7VsIWqhT LCrwM+7Ym9oc+fxPGgkmYAD7UG0pTWajXJmiV+g3FMIZc64e6L/s3erHXDGzGETaIK+FzI5DL3ThR 89JyvOqhA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iHsCX-0004Eu-4o; Tue, 08 Oct 2019 16:19:05 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.2 #3 (Red Hat Linux)) id 1iHsCT-0004E1-AF for linux-arm-kernel@lists.infradead.org; Tue, 08 Oct 2019 16:19:02 +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 61D9B1570; Tue, 8 Oct 2019 09:18:56 -0700 (PDT) Received: from [10.1.197.57] (e110467-lin.cambridge.arm.com [10.1.197.57]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2E2823F6C4; Tue, 8 Oct 2019 09:18:55 -0700 (PDT) Subject: Re: [PATCH] arm64: lse: fix LSE atomics with LLVM's integrated assembler To: Sami Tolvanen , Nick Desaulniers References: <20191007201452.208067-1-samitolvanen@google.com> From: Robin Murphy Message-ID: Date: Tue, 8 Oct 2019 17:18:53 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191008_091901_399925_AEDF1EBA X-CRM114-Status: GOOD ( 12.76 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kees Cook , Catalin Marinas , LKML , clang-built-linux , Andrew Murray , Will Deacon , Linux ARM Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 08/10/2019 16:22, Sami Tolvanen wrote: > On Mon, Oct 7, 2019 at 2:46 PM 'Nick Desaulniers' via Clang Built > Linux wrote: >> I'm worried that one of these might lower to LSE atomics without >> ALTERNATIVE guards by blanketing all C code with `-march=armv8-a+lse`. > > True, that's a valid concern. I think adding the directive to each > assembly block is the way forward then, assuming the maintainers are > fine with that. It's definitely a valid concern in principle, but in practice note that lse.h ends up included in ~99% of C files, so the extension is enabled more or less everywhere already. (based on a quick hack involving '#pragma message' and grepping the build logs) Robin. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel