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 mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D77DC433F5 for ; Tue, 25 Jan 2022 14:25:51 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id D322549EDE; Tue, 25 Jan 2022 09:25:50 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Hgcu7A3LaeAD; Tue, 25 Jan 2022 09:25:49 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id B69FC49EBC; Tue, 25 Jan 2022 09:25:49 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id A886B49B08 for ; Tue, 25 Jan 2022 09:25:48 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gV8dImXTR79f for ; Tue, 25 Jan 2022 09:25:47 -0500 (EST) Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 91261404FD for ; Tue, 25 Jan 2022 09:25:47 -0500 (EST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AB873B81800; Tue, 25 Jan 2022 14:25:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D0BFC340E0; Tue, 25 Jan 2022 14:25:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643120744; bh=AAEEAEnnyX/L1DH7WC8/0Km2eJQRUtDNv04WJ7pfQAA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c335kB7NRNmQyuY3LbHiWWUUhNJ86fldQs6hst8PLp9IMNMaTRN+9AST0UapK9FlL AK0pkuZN9WcyrHbIDWgEKl5boRHWH1vcesmo92RMXQiXLDwjDqPkBK/6E/DEq/BnOj lXmRAG6UlNVTl5CkM7xcz0u2Ts865Dne2q5eb8HhwdDDprTAi9JvNyDQLmKw6CRO1l 8nbyFXkKAxS7aNDSRxh4RNCcpOgTCMLUsknYPo1lthhjJRQY/FjNGcTz0HrDpmN6NX Q3J8V7F1L3b/krG3MoowyL/HCNcVRyICWb2XfJtlsbl12TQ5hbZHQ6RorbzTCLFKNf 9lN/Cc7njaAlQ== Date: Tue, 25 Jan 2022 14:25:38 +0000 From: Mark Brown To: Marc Zyngier Subject: Re: [PATCH v8 25/38] KVM: arm64: Trap SME usage in guest Message-ID: References: <20220125001114.193425-1-broonie@kernel.org> <20220125001114.193425-26-broonie@kernel.org> <87y2346on8.wl-maz@kernel.org> <87v8y86jdg.wl-maz@kernel.org> MIME-Version: 1.0 In-Reply-To: <87v8y86jdg.wl-maz@kernel.org> X-Cookie: The second best policy is dishonesty. Cc: Basant Kumar Dwivedi , Will Deacon , Luis Machado , Szabolcs Nagy , Catalin Marinas , Shuah Khan , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, Alan Hayward , Shuah Khan , kvmarm@lists.cs.columbia.edu, Salil Akerkar X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============3725826571112692785==" Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu --===============3725826571112692785== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="YEhifuxFIuvQlt0I" Content-Disposition: inline --YEhifuxFIuvQlt0I Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jan 25, 2022 at 01:21:47PM +0000, Marc Zyngier wrote: > Mark Brown wrote: > > OK, I'll remove the defensiveness here. FGT is mandatory from v8.6 and > > SME is a v9 feature so people shouldn't build a SME implementation that > > lacks FGT. > Can you then please make it that SME doesn't get enabled at all if FGT > isn't present? It would also be good to have a clarification in the > architecture that it isn't allowed to build SME without FGT (specially > given that v9.0 is congruent to v8.5, and thus doesn't have FGT). Right, this should be handled by the time the full spec is published - it's an issue people are aware of and it's not something that should ever get built. It would be good to explicitly handle the dependency in the cpufeature stuff, we'll have other issues like this, but I'd like to handle that separately since at first look doing it properly is a bit of surgery on cpufeature and the series is already rather large. --YEhifuxFIuvQlt0I Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmHwCGEACgkQJNaLcl1U h9B+Iwf/UgQEid+JO2QkdGR/J+t4OgReatZ/I57vAqYAESGun3agL/oLDXInx20v eCGN2xA+iulobCXCAGt6m6oRNJhjux5DYsqlrakgTTzcFXDDli+O2igLbjtk0mGh KkLjqK5y4ZNaspiYv8TncnOA6zG6KsMiRVQ+2/K+sfFaFXELoqsVdoYRDfxpEYRH P8/ii51TJiXcpLSQ2XVUy1s3Zux3OqDGq3BPE9C8NRG0E24/Ca+fcH0QyWPFKfPH OAgFgzukSkGpPDLJbnd1p3I3AONEyVyRBbYxNTisQiOPfhvl17mGFbaUzQumzkdY DCzSIFm7LoUu+rhxz0R6Xjhl27iSrA== =+7k2 -----END PGP SIGNATURE----- --YEhifuxFIuvQlt0I-- --===============3725826571112692785== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm --===============3725826571112692785==-- 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 C140CC433F5 for ; Tue, 25 Jan 2022 14:27:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc: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=y7ph57YroVp9mKd8y7ygi94eeec8jGqn3qLGtE4wtAg=; b=HSNbh93wNGX18FFUSM3O9kIq8S +wTeQqybFHadKOcnDYAVxPSeInTwCULCLmNKitc3Tlgygbj5ShPdCrcO5MMq3msjBloi84y+v5Doq NbYMvCHXgx77cLd+MA6LjOZXNXPoricmB/sO3ju9oNsezWCDnPjMSlylskSfVm8R+or9UbUYVUZ5r LHGV9I8MdeRciPvLi4YFijawnH1cDydv+Q6KmxHFMfI3zSSwhs8tz5eMS4rNkRvScCGiXv+mVr0gC 5ma2WsqYi/t0rRT8SOooAwRqs9wmnKvQiuoiTENhYiy7UTxZxxy+cQKOgVb5bKiiDU+mybqxYZuyZ 8VBm0juw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nCMlc-0087p4-Io; Tue, 25 Jan 2022 14:25:52 +0000 Received: from ams.source.kernel.org ([145.40.68.75]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nCMlX-0087nQ-IJ for linux-arm-kernel@lists.infradead.org; Tue, 25 Jan 2022 14:25:49 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id AB873B81800; Tue, 25 Jan 2022 14:25:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D0BFC340E0; Tue, 25 Jan 2022 14:25:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643120744; bh=AAEEAEnnyX/L1DH7WC8/0Km2eJQRUtDNv04WJ7pfQAA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c335kB7NRNmQyuY3LbHiWWUUhNJ86fldQs6hst8PLp9IMNMaTRN+9AST0UapK9FlL AK0pkuZN9WcyrHbIDWgEKl5boRHWH1vcesmo92RMXQiXLDwjDqPkBK/6E/DEq/BnOj lXmRAG6UlNVTl5CkM7xcz0u2Ts865Dne2q5eb8HhwdDDprTAi9JvNyDQLmKw6CRO1l 8nbyFXkKAxS7aNDSRxh4RNCcpOgTCMLUsknYPo1lthhjJRQY/FjNGcTz0HrDpmN6NX Q3J8V7F1L3b/krG3MoowyL/HCNcVRyICWb2XfJtlsbl12TQ5hbZHQ6RorbzTCLFKNf 9lN/Cc7njaAlQ== Date: Tue, 25 Jan 2022 14:25:38 +0000 From: Mark Brown To: Marc Zyngier Cc: Catalin Marinas , Will Deacon , Shuah Khan , Shuah Khan , Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , James Morse , Alexandru Elisei , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, kvmarm@lists.cs.columbia.edu Subject: Re: [PATCH v8 25/38] KVM: arm64: Trap SME usage in guest Message-ID: References: <20220125001114.193425-1-broonie@kernel.org> <20220125001114.193425-26-broonie@kernel.org> <87y2346on8.wl-maz@kernel.org> <87v8y86jdg.wl-maz@kernel.org> MIME-Version: 1.0 In-Reply-To: <87v8y86jdg.wl-maz@kernel.org> X-Cookie: The second best policy is dishonesty. X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220125_062547_789111_89180CDC X-CRM114-Status: GOOD ( 18.91 ) 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: , Content-Type: multipart/mixed; boundary="===============0308315803891346957==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============0308315803891346957== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="YEhifuxFIuvQlt0I" Content-Disposition: inline --YEhifuxFIuvQlt0I Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jan 25, 2022 at 01:21:47PM +0000, Marc Zyngier wrote: > Mark Brown wrote: > > OK, I'll remove the defensiveness here. FGT is mandatory from v8.6 and > > SME is a v9 feature so people shouldn't build a SME implementation that > > lacks FGT. > Can you then please make it that SME doesn't get enabled at all if FGT > isn't present? It would also be good to have a clarification in the > architecture that it isn't allowed to build SME without FGT (specially > given that v9.0 is congruent to v8.5, and thus doesn't have FGT). Right, this should be handled by the time the full spec is published - it's an issue people are aware of and it's not something that should ever get built. It would be good to explicitly handle the dependency in the cpufeature stuff, we'll have other issues like this, but I'd like to handle that separately since at first look doing it properly is a bit of surgery on cpufeature and the series is already rather large. --YEhifuxFIuvQlt0I Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmHwCGEACgkQJNaLcl1U h9B+Iwf/UgQEid+JO2QkdGR/J+t4OgReatZ/I57vAqYAESGun3agL/oLDXInx20v eCGN2xA+iulobCXCAGt6m6oRNJhjux5DYsqlrakgTTzcFXDDli+O2igLbjtk0mGh KkLjqK5y4ZNaspiYv8TncnOA6zG6KsMiRVQ+2/K+sfFaFXELoqsVdoYRDfxpEYRH P8/ii51TJiXcpLSQ2XVUy1s3Zux3OqDGq3BPE9C8NRG0E24/Ca+fcH0QyWPFKfPH OAgFgzukSkGpPDLJbnd1p3I3AONEyVyRBbYxNTisQiOPfhvl17mGFbaUzQumzkdY DCzSIFm7LoUu+rhxz0R6Xjhl27iSrA== =+7k2 -----END PGP SIGNATURE----- --YEhifuxFIuvQlt0I-- --===============0308315803891346957== 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 --===============0308315803891346957==-- 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8D6BC4332F for ; Tue, 25 Jan 2022 14:36:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239014AbiAYOgB (ORCPT ); Tue, 25 Jan 2022 09:36:01 -0500 Received: from ams.source.kernel.org ([145.40.68.75]:55734 "EHLO ams.source.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1388731AbiAYOZx (ORCPT ); Tue, 25 Jan 2022 09:25:53 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CF378B80ED5 for ; Tue, 25 Jan 2022 14:25:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D0BFC340E0; Tue, 25 Jan 2022 14:25:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1643120744; bh=AAEEAEnnyX/L1DH7WC8/0Km2eJQRUtDNv04WJ7pfQAA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=c335kB7NRNmQyuY3LbHiWWUUhNJ86fldQs6hst8PLp9IMNMaTRN+9AST0UapK9FlL AK0pkuZN9WcyrHbIDWgEKl5boRHWH1vcesmo92RMXQiXLDwjDqPkBK/6E/DEq/BnOj lXmRAG6UlNVTl5CkM7xcz0u2Ts865Dne2q5eb8HhwdDDprTAi9JvNyDQLmKw6CRO1l 8nbyFXkKAxS7aNDSRxh4RNCcpOgTCMLUsknYPo1lthhjJRQY/FjNGcTz0HrDpmN6NX Q3J8V7F1L3b/krG3MoowyL/HCNcVRyICWb2XfJtlsbl12TQ5hbZHQ6RorbzTCLFKNf 9lN/Cc7njaAlQ== Date: Tue, 25 Jan 2022 14:25:38 +0000 From: Mark Brown To: Marc Zyngier Cc: Catalin Marinas , Will Deacon , Shuah Khan , Shuah Khan , Alan Hayward , Luis Machado , Salil Akerkar , Basant Kumar Dwivedi , Szabolcs Nagy , James Morse , Alexandru Elisei , Suzuki K Poulose , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org, kvmarm@lists.cs.columbia.edu Subject: Re: [PATCH v8 25/38] KVM: arm64: Trap SME usage in guest Message-ID: References: <20220125001114.193425-1-broonie@kernel.org> <20220125001114.193425-26-broonie@kernel.org> <87y2346on8.wl-maz@kernel.org> <87v8y86jdg.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="YEhifuxFIuvQlt0I" Content-Disposition: inline In-Reply-To: <87v8y86jdg.wl-maz@kernel.org> X-Cookie: The second best policy is dishonesty. Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org --YEhifuxFIuvQlt0I Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Jan 25, 2022 at 01:21:47PM +0000, Marc Zyngier wrote: > Mark Brown wrote: > > OK, I'll remove the defensiveness here. FGT is mandatory from v8.6 and > > SME is a v9 feature so people shouldn't build a SME implementation that > > lacks FGT. > Can you then please make it that SME doesn't get enabled at all if FGT > isn't present? It would also be good to have a clarification in the > architecture that it isn't allowed to build SME without FGT (specially > given that v9.0 is congruent to v8.5, and thus doesn't have FGT). Right, this should be handled by the time the full spec is published - it's an issue people are aware of and it's not something that should ever get built. It would be good to explicitly handle the dependency in the cpufeature stuff, we'll have other issues like this, but I'd like to handle that separately since at first look doing it properly is a bit of surgery on cpufeature and the series is already rather large. --YEhifuxFIuvQlt0I Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmHwCGEACgkQJNaLcl1U h9B+Iwf/UgQEid+JO2QkdGR/J+t4OgReatZ/I57vAqYAESGun3agL/oLDXInx20v eCGN2xA+iulobCXCAGt6m6oRNJhjux5DYsqlrakgTTzcFXDDli+O2igLbjtk0mGh KkLjqK5y4ZNaspiYv8TncnOA6zG6KsMiRVQ+2/K+sfFaFXELoqsVdoYRDfxpEYRH P8/ii51TJiXcpLSQ2XVUy1s3Zux3OqDGq3BPE9C8NRG0E24/Ca+fcH0QyWPFKfPH OAgFgzukSkGpPDLJbnd1p3I3AONEyVyRBbYxNTisQiOPfhvl17mGFbaUzQumzkdY DCzSIFm7LoUu+rhxz0R6Xjhl27iSrA== =+7k2 -----END PGP SIGNATURE----- --YEhifuxFIuvQlt0I--