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 BD81CC43331 for ; Wed, 25 Mar 2020 12:34:01 +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 8B5872076A for ; Wed, 25 Mar 2020 12:34:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="gPOX1gP1" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B5872076A 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-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LDI/k90tVfLwnZmUrm+7Mr3H+FhnL+rIWD0KoF25k8Q=; b=gPOX1gP1YlK+Tv cPS/N1CbZ5D9Vax4qRN0xNMujTixxt6j6sAqVl3Snr6z+/BbYo9y+Q2L9MhadgurzoU27SPiv+Ijq cFpno6Z+EBILtW+Zonihg04X0JESDtty1hFKuOA/HFgb5l41wUEM1Qhstm5J1R0IgGxTYfXUt8pOJ skeSW6HAFpAKqiM7M81J/1Zsrn9QnEnfNPaNm5nLBzZH4+TseXLvg4CCCJeSow/aNSvkjiWA7906g LV0k0wNL67jv9OB1p66mXReE8c2hr0vi2xfUkyiS4BS3b9Bix5gLk67VWG834HdoPp210COV+pqlj BhohmOUr8nNEoBlZFtCA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jH5EO-0008Jv-9S; Wed, 25 Mar 2020 12:34:00 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jH5CX-0006nW-EA for linux-arm-kernel@lists.infradead.org; Wed, 25 Mar 2020 12:32:18 +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 C79DC31B; Wed, 25 Mar 2020 05:32:04 -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 ESMTPSA id C71F43F71F; Wed, 25 Mar 2020 05:32:03 -0700 (PDT) Date: Wed, 25 Mar 2020 12:31:59 +0000 From: Mark Rutland To: Mark Brown Subject: Re: [PATCH 0/3] arm64: Open code .arch_extension Message-ID: <20200325123157.GA12236@lakrids.cambridge.arm.com> References: <20200325114110.23491-1-broonie@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200325114110.23491-1-broonie@kernel.org> User-Agent: Mutt/1.11.1+11 (2f07cb52) (2018-12-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200325_053205_544493_030EF9A2 X-CRM114-Status: GOOD ( 10.90 ) 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: Eric Biggers , Catalin Marinas , linux-crypto@vger.kernel.org, Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Mar 25, 2020 at 11:41:07AM +0000, Mark Brown wrote: > Since inserting BTI landing pads into assembler functions will require > us to change the default architecture we need a way to enable > extensions without hard coding the architecture. Assuming we'll poke the toolchain folk, let's consider alternative ways around this in the mean time. Is there anything akin to push/pop versions of .arch directitves that we can use around the BTI instructions specifically? ... or could we encode the BTI instructions with a .inst, and wrap those in macros so that GAS won't complain (like we do for mrs_s and friends)? ... does asking GCC to use BTI for C code make the default arch v8.5 for inline asm, or does it do something special to allow BTI instructions in specific locations? Thanks, Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel