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,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 33D17C33CB1 for ; Wed, 15 Jan 2020 14:09:04 +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 05B4824656 for ; Wed, 15 Jan 2020 14:09:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="HSyozwCD"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sirena.org.uk header.i=@sirena.org.uk header.b="NZYyV2aF" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 05B4824656 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=uPrfzDq6BRgQdYuovptZgoa2rEDXSJm4+Xh45YpIUqE=; b=HSyozwCDyt/wFEMO8x/0Q/CRt fbVpjaGd9e1hM+U2bprKJ9pLfrf0ThFTdbx6Y/nAUjQpWOCwyry04em8pJqxmCyGK+VCSkJSV2NG8 OzVqGta76yNzVMRx3Ag3MFWpBJWyFR7jK3iHhJZNghh5rlXkQYGdp0ouvhjN0ynq44TxEiuQLTQwv ftYTAg5NW+JMNeSLoJwPXthM2cIh3sQ60NOs1ONY5nOAMmKN+eR7MwEpe33jtM9ODLqbG6jMbYrUh ZXJYvOWpTsRVLlDaomlW1W2pgzn+BduFrmE5/JJ2YIGzuxujWGS4a8ZSVWxw/NLvHlGN1OxuC9orD RBH/HFiXw==; 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 1irjLz-0007FC-6Y; Wed, 15 Jan 2020 14:09:03 +0000 Received: from heliosphere.sirena.org.uk ([172.104.155.198]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1irjLr-0007BN-Vc for linux-arm-kernel@lists.infradead.org; Wed, 15 Jan 2020 14:09:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sirena.org.uk; s=20170815-heliosphere; h=In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=tvoOm9SC39gbHNsQ3X/YfZ4y2QkJdagzVDfgqU/mXOI=; b=NZYyV2aFUgZ5OtL//X6PXLLbF No+mXVFXj/OMf/rou0wLobMtvrXAOa7ATGRmu1O4C7FXPH5mjC2EisVLzDXQsqz6QIF9aVe/cItgU ZKMFcJ8csH0j5reoZRLcMWTB9KdFIDjhHtYShTVMjn+blZqaFW9no61T2CLSCXKGnQJsU=; Received: from fw-tnat-cam5.arm.com ([217.140.106.53] helo=fitzroy.sirena.org.uk) by heliosphere.sirena.org.uk with esmtpsa (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1irjLn-0005t5-QV; Wed, 15 Jan 2020 14:08:51 +0000 Received: by fitzroy.sirena.org.uk (Postfix, from userid 1000) id 79C3CD01965; Wed, 15 Jan 2020 14:08:51 +0000 (GMT) Date: Wed, 15 Jan 2020 14:08:51 +0000 From: Mark Brown To: Will Deacon Subject: Re: [PATCH v9 1/4] arm64: Add initial support for E0PD Message-ID: <20200115140851.GJ3897@sirena.org.uk> References: <20191111185243.42638-1-broonie@kernel.org> <20191111185243.42638-2-broonie@kernel.org> <20200115135426.GB27473@willie-the-truck> MIME-Version: 1.0 In-Reply-To: <20200115135426.GB27473@willie-the-truck> X-Cookie: Programming is an unnatural act. 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-20200115_060856_021637_0EC54499 X-CRM114-Status: GOOD ( 11.12 ) 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: Catalin Marinas , linux-arm-kernel@lists.infradead.org, Suzuki K Poulose Content-Type: multipart/mixed; boundary="===============6583851216712373752==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============6583851216712373752== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="mjUDp/cLGeqUhYyE" Content-Disposition: inline --mjUDp/cLGeqUhYyE Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jan 15, 2020 at 01:54:27PM +0000, Will Deacon wrote: > On Mon, Nov 11, 2019 at 06:52:40PM +0000, Mark Brown wrote: > > + E0PD (part of the ARMv8.5 extensions) allows us to ensure > > + that EL0 accesses made via TTBR1 always fault in constant time, > > + providing benefits to KPTI with lower overhead and without > > + disrupting legitimate access to kernel memory such as SPE. > This doesn't quite make sense to me, since E0PD doesn't really benefit > KPTI. Mind if I fold in the diff below? > - providing benefits to KPTI with lower overhead and without > - disrupting legitimate access to kernel memory such as SPE. > + providing similar benefits to KASLR as those provided by KPTI, but > + with lower overhead and without disrupting legitimate access to > + kernel memory such as SPE. Yes, there was supposed to be a "similar" in there, must've got dropped at some point during review I think. Reviwed-by: Mark Brown --mjUDp/cLGeqUhYyE Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl4fHPIACgkQJNaLcl1U h9BswQf7BK3O7DkS9agBg3lUyhCuxYVp5vUSwTTWMmhT8dpcd5xwMTUyH0BhoLgB txpJ6kpb/6lb3mCq4MZPPaybkmJ5lyyp4QkriKVLUbZ7LWImi+IcPXsTkeAWSPvi e5KS+YGNJdC+0zi/A8KCyMK+qYatjR3+7u+JoNxjbYK9wvts6DE+jhZao/19ch1N lOs9A3+vRMsItztN8G0LLUZuyUC91BiQYtRkj4j0e8VJaDxHz0UBMYtWHJQ226iH KxNGdHuBiJ8PjgeT7y7CRNcRiv/EJfTnR0mAGyDQ0hiyRQOL/pgbgnzIRAWN4adM y5Buy+fWrg4JbQ9SehrxpsQMOLTvLw== =lOKt -----END PGP SIGNATURE----- --mjUDp/cLGeqUhYyE-- --===============6583851216712373752== 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 --===============6583851216712373752==--