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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6468BC61DF4 for ; Sat, 25 Nov 2023 12:02:57 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id EC6C68D00B2; Sat, 25 Nov 2023 07:02:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E53B18D0096; Sat, 25 Nov 2023 07:02:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CF0DC8D00B2; Sat, 25 Nov 2023 07:02:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id BAEEE8D0096 for ; Sat, 25 Nov 2023 07:02:56 -0500 (EST) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 7AA328040B for ; Sat, 25 Nov 2023 12:02:56 +0000 (UTC) X-FDA: 81496340352.18.CE0C97F Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf13.hostedemail.com (Postfix) with ESMTP id B81CC20020 for ; Sat, 25 Nov 2023 12:02:53 +0000 (UTC) Authentication-Results: imf13.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=diLxf7zo; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf13.hostedemail.com: domain of broonie@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=broonie@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1700913773; a=rsa-sha256; cv=none; b=h4C3opYZ/E7aosOg1Kq2xjkT09GSNnbqlSg5Tl+4e1Mcvxq4LM/ddIwnssfJiNr0fCrH/I IIK6FcJU8jiFCuMS6iVPuvcA4KbQABMxO/9EV0Am0ojg6Q6Z8TWWd/Jy30X1KK/W1uOawz Xs/mClFj4njLWpS9I6dToZbo6vGz4SM= ARC-Authentication-Results: i=1; imf13.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=diLxf7zo; dmarc=pass (policy=none) header.from=kernel.org; spf=pass (imf13.hostedemail.com: domain of broonie@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=broonie@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1700913773; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=0cLp0acvObxccvbH1uQ3hUmDBLViDZNwSqftraNfHBI=; b=Cb1L6IXC+iAYD18pLVMlwZRYxvz7BKKTfUgF8eyAoh/5MKY+8NIZZEpGLtnMy0NBp2rNqH ThM5uUl75/P2SINn5UZk88nZDP2s9SYBJ41b2dylMqTBorY2qd4fqLA1nXfrrCjxmWs1Nq cYjMUrOIQyG3I7djAaRECppToVrabM8= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id BEFEE60B80; Sat, 25 Nov 2023 12:02:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DDF71C433C7; Sat, 25 Nov 2023 12:02:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1700913772; bh=tuP3mnsyjalSFkRoYilZotwb2CTmKBTRrdYxee7FyEU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=diLxf7zoZzu/TtTiAEGeGm69Lqim48csQd7BtltmOaYD2RG8p+qiG5DOP5EEitwMZ 4IOBNKkcnNTeg9qr/Weow3vmUlYvtkYy1eFNkWzLnPE7/f7E15JVWJzZOmZpOOCP3l VYDc8ri5hrWYdfpeQLLTWdJR/4NO4Az3CEaPJnGAU6gK6MAo4Gogk42UooIz8GuA8w WBXPVwIBcoO4EJcTokwYORM3Wd7E3CsV3uS8wfLicwSx222uEVefKFvlYlUFVmbcIb +i6ZeuqTRu5KKdT5R14SjAa8nznIMB2NoKcXmuzfK/xmNpnGFGTfOg2CigmxQxPEtq JSO854vAMR2FQ== Date: Sat, 25 Nov 2023 12:02:49 +0000 From: Mark Brown To: Joey Gouly Cc: linux-arm-kernel@lists.infradead.org, akpm@linux-foundation.org, aneesh.kumar@linux.ibm.com, catalin.marinas@arm.com, dave.hansen@linux.intel.com, maz@kernel.org, oliver.upton@linux.dev, shuah@kernel.org, will@kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, James Morse , Suzuki K Poulose , Zenghui Yu Subject: Re: [PATCH v3 05/25] arm64: context switch POR_EL0 register Message-ID: References: <20231124163510.1835740-1-joey.gouly@arm.com> <20231124163510.1835740-6-joey.gouly@arm.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="ow+J4bMvxCVXQcLF" Content-Disposition: inline In-Reply-To: <20231124163510.1835740-6-joey.gouly@arm.com> X-Cookie: Slow day. Practice crawling. X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: B81CC20020 X-Stat-Signature: mqydpmpbawzenq15o53ko5faau1hqt9e X-HE-Tag: 1700913773-728493 X-HE-Meta: U2FsdGVkX1/5m7uh+jYaBW+PSVZZO4nyAmsPOmmVuv82ij5u5tt3mGuKMQsbBgzUaoYBKAjoP2rilBVWqQkubnV7LxnUUg0Vu+JAGMQLfM4d8z3889vLoPP5d0R9PFMkAR0nEvRhbFGaSnnnEGmcFeTQCA0WR2dBlkKS3yec1nYZO2hAvBdvjhfXndkN/KEVc3IlnrnOM5bfJLjcKHLzQvaR3duvhj5yaMcbwyybdjxqDg8TAb5fcO9fqzgHHoTpZxAD5IBc4wbQYoz7Ogw/WW09fLTuClM42BAzB5rZnIySxZbdaeF0YJx10A38hJNVelA5v4hWeMxtAsu3rE94134k31jh3l8kUoOcb88IkRyq2+KVt2sqsIiV+hZEnSmxJkJw7EoP0uZKxH6y+aA45plFGokE5SucHwPYYCajn7FHCE/qyuPKd7Yhv21xrEydUznkOxF9OJN1GrGDSRz+6U6JeOhWRE9sT1JI5iZoAvuuZKbtGHVflosYoq1SYMMfN1Db98fJjWz0gP/5+RwPUldv7OYoO+FPHZgLg60BE01rwzOwkg5KafN3E+DjwUxOsvoxDQxaxwUFirsXDzfjthdBQgsfHtWkgeASmSzvJ6IIDv7iy8WiXlm8xuYxGNGKGzdb9fSUwXymIeAZK/qRvb8seWlCVDJQMqFmm0ZkiEWjwZHFi7q8Lq7ZgZpF6P2DYowMKRjXBHbZTdGQ+pZFUqG9dkqdjLdmenbGv/LHcBOTHqq3SZKUN7gCWvka885CLV2OAu8eDeJehFYJ6Dm8xTP/Z3cM8qj7lYvMf+osSkgNjA7NSMi/Wl/JVAM3qpefEXtg9ygW8pzINawTLaUTObZ+deOs+2AqllyexWMUjXhVZqKw+6MYCWLSoqEVUCol/7TaWV1F9dqC9SMoOOvuzmmWWOtIcVYR/XPmfX7DFirLiOuxxUxqObUIh1VWDHj/T+Ytwfp5FKFhm6pZsFm 7/x30nyB ekb/4vXpYTT6jdvoadbmi0M0Xi4CUsKY/IwEJr1HaiVUWYit4pw7uzgwy/faDPKAi9CmRE5wUB6jpeokBeblXob1JpBW8WnIQtBh5D6MaLplHbirUeaQetlPTb6Ft2gygu9k0aF15asFm6Ac4f0iFpR+6gMeS1xBH1k2Jy/JJGunD2p5DvT/S/s3zVSCpXYYt1sYFLhpVX8lgHRtJpZOvpDRY0z4Ob7zO2AV65rn9jHnLTXq6fKFNJZAUSPuLaS7Azsd5IKg63pSC15Jtv5nv2djnjJ2S4Z1Ual22Z0dmC/1dTcQ= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: --ow+J4bMvxCVXQcLF Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Nov 24, 2023 at 04:34:50PM +0000, Joey Gouly wrote: > +static void flush_poe(void) > +{ > + if (system_supports_poe()) > + write_sysreg_s(POR_EL0_INIT, SYS_POR_EL0); > +} Here we have no isb()... > +static void permission_overlay_switch(struct task_struct *next) > +{ > + if (system_supports_poe()) { > + current->thread.por_el0 =3D read_sysreg_s(SYS_POR_EL0); > + if (current->thread.por_el0 !=3D next->thread.por_el0) { > + write_sysreg_s(next->thread.por_el0, SYS_POR_EL0); > + isb(); > + } > + } > +} =2E..but here we do, I'd expect them to be consistent. =20 If the barrier is needed it'd probably be helpful to have a comment explaining why we need it before the ERET. --ow+J4bMvxCVXQcLF Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAmVh4mYACgkQJNaLcl1U h9BPiwf7BZimFuxNSYhP3hqXG6y4xu3e8rftssQCYtcNtXnIVlsn/6C7YMdoBuw2 TV0LvyB1ZLjJRA8D9lBOsGm/MyW/yw15yHRHUYs+F+2+1mr8juEVIt+311HWRl9b JgBFfc+5fmzNpHr7xLAkgLY49z+cm0YXSx8NbyAO71UZj/hOyGsTuzVEoflXWKmG bmTAK2h5QqW3gRwf/Ty/BE9bCDGp7xLKTZXSdRCZxS+321SCBqIZbalqJ53oePCT YqYDr7McCoyhEv9QYhg3hh1+Yeg5ieFylfAQJmMzd8r2MU/zdYAbS8zFmPNPMBKP XhIttzUePYRY9o9GJyOLYSjqKkZ9Yg== =iEOq -----END PGP SIGNATURE----- --ow+J4bMvxCVXQcLF--