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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,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 14751C55186 for ; Thu, 23 Apr 2020 11:18:13 +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 D38A12071C for ; Thu, 23 Apr 2020 11:18:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="pQgw9S6l"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="GJCLBypK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D38A12071C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org 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: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-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=y7LrmkrESLC4/Nbcs/Q8ZhqgLaHtLWEGtNUL8aLf6dc=; b=pQgw9S6lAqnK4ZTT/0S+tZSX9 GB5HSnSqr9WgH1puzzyCmZeOPPcaBUkS17PUqbgPDqi7GzMYGXGl+3QeQk2PDlyzYZzyrCLmdom1C TCoF/10LjEum00HVgISX5ImRAnDT3acLs1SznzCApjqpnHkA3w0RjNqP5d5W0MUpzY0gt9WKzM7yM /+GWzRi8Se2/jFpqR+6c+1O7yvzxLrq+sCjHqRemffPoXJ4l0Fkmf1yEnU8scUYbmzBJ3BaF5ZqQ3 WhI0Zp+mPj3Zo9CLeR5ZdsWV866Fcgsncdw4KkzHViFZPXcOAsAGi7IrCQ8YgnoxX217Bwa9YuU6E P/vq3KqRg==; 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 1jRZrt-0000jb-LD; Thu, 23 Apr 2020 11:18:09 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jRZrq-0000iY-NL for linux-arm-kernel@lists.infradead.org; Thu, 23 Apr 2020 11:18:07 +0000 Received: from localhost (fw-tnat.cambridge.arm.com [217.140.96.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id CC7C42071C; Thu, 23 Apr 2020 11:18:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587640686; bh=CJNoxUHgvPPi6Qz7NFobk1lVAPAIYHcYUb9EZMXpEDM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GJCLBypKIbMdCv9trAb+I5k8OsD4fiQDXU6P5swdLzc3OXz+KZh52sGY0IBsQmZDl Zvp5rXoeiBeVugDynp8aCksN9cDMZGjGbBC6IBqfSU6djcbF/ZVvxT5Wo/Kzq5v81F jiqFm0EGjrdCwq8CnID2TyHz7Pwr8R1suZddVsfc= Date: Thu, 23 Apr 2020 12:18:03 +0100 From: Mark Brown To: Catalin Marinas Subject: Re: [PATCH 0/3] arm64: Open code .arch_extension Message-ID: <20200423111803.GG4808@sirena.org.uk> References: <20200325114110.23491-1-broonie@kernel.org> <20200325115038.GD4346@sirena.org.uk> <20200422180027.GH3585@gaia> MIME-Version: 1.0 In-Reply-To: <20200422180027.GH3585@gaia> X-Cookie: This unit... must... survive. User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200423_041806_778370_99A6002E X-CRM114-Status: GOOD ( 17.01 ) 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 , Will Deacon , Ard Biesheuvel , linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org Content-Type: multipart/mixed; boundary="===============2231390729745644593==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============2231390729745644593== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="yQbNiKLmgenwUfTN" Content-Disposition: inline --yQbNiKLmgenwUfTN Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Apr 22, 2020 at 07:00:28PM +0100, Catalin Marinas wrote: > On Wed, Mar 25, 2020 at 11:50:38AM +0000, Mark Brown wrote: > > Since BTI is a mandatory feature of v8.5 there is no BTI arch_extension, > > you can only enable it by moving the base architecture to v8.5. You'd > > need to use .arch and that feels likely to find us sharp edges to run > > into. > For MTE, .arch armv8-a+memtag won't work since this is only available > with armv8.5-a. My preference would be to have the highest arch version > supported by the kernel in the assembler.h file, i.e. ".arch armv8.5-a" > followed by .arch_extension in each .S file, as needed. I think we decided that .arch_extension was too new to be used for things like the crypto stuff where we still support older toolchains? > Forcing .S files to armv8.5 would not cause any problems with > the base armv8.0 that the kernel image support since it shouldn't change > the opcodes gas generates. The .S files would use alternatives anyway > (or simply have code not called). We do loose the checking that the assembler does that nobody used a newer feature by mistake but yeah, shouldn't affect the output. > The inline asm is slightly more problematic, especially with the clang > builtin assembler which goes in a single pass. But we could do something > similar to what we did with the LSE atomics and raising the base of the > inline asm to armv8.5 (or 8.6 etc., whatever we need in the future). FWIW I did something different to this for BTI so I wasn't using the instructions directly so I was going to abandon this series. --yQbNiKLmgenwUfTN Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl6heWoACgkQJNaLcl1U h9CcYQf/YAY5cG0Z+KJA/4mDzsfJIXzFJiQYAT2tuyJHZjf/3CTPE3It3sTDp4i1 yxquKeKVGvnDrZobr9Mlb8GA92dM7ALcN8GEYLMqYWn4YFH5YGTrO2ThNMwGtFW2 yWun9x3SKPg8HWXOTmuumLyUXtnV7dcr21zQa+jgY6x4xyumKXs2xUXe85geF3Kl CHWbPxMxwIHcw1R+hfAhqY18gBA9RRZ5Cdb9Dronv+EXpj7gpCi3kqjAuGqtzx6f tocf6Rd8paJ1PRftJEBb/7Vy00mWBRQGgxiVLSNdxGWe15SYgswYrsuafKEOh3Qx BRw4/z8CFxIpdOgEPm0vi4cFX8+VIg== =kbYd -----END PGP SIGNATURE----- --yQbNiKLmgenwUfTN-- --===============2231390729745644593== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============2231390729745644593==--