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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id EFF4CC79F9F for ; Thu, 10 Sep 2026 09:21:41 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ED37B6B008C; Thu, 10 Sep 2026 05:21:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id EA4036B0098; Thu, 10 Sep 2026 05:21:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DE1E86B0099; Thu, 10 Sep 2026 05:21:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id B8E956B008C for ; Thu, 10 Sep 2026 05:21:40 -0400 (EDT) Received: from smtpin23.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id C3CC01A0497 for ; Thu, 10 Sep 2026 09:21:39 +0000 (UTC) X-FDA: 85197309918.23.451BDD9 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf22.hostedemail.com (Postfix) with ESMTP id 4077FC0008 for ; Thu, 10 Sep 2026 09:21:38 +0000 (UTC) Authentication-Results: imf22.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="SWenu4/b"; spf=pass (imf22.hostedemail.com: domain of thierry.reding@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=thierry.reding@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1789032098; b=4mSuOszuLvuBJV+gb2K5fdT8Hm1z94XtyYjwLFORIP+sz6n2TEIz9DlLrhGuWvFdCiBC9i qdPmExagtxan8U1rC/X4asvBOdbxmv8bmQGRQT4BKxR6u1cW83EHXmSdgwahFUv6zqUzv+ HMUfCkej5S/wM05y9JZJcTFk+jpLVRg= ARC-Authentication-Results: i=1; imf22.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="SWenu4/b"; spf=pass (imf22.hostedemail.com: domain of thierry.reding@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=thierry.reding@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1789032098; 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=etegQPhHDYYXKpgN5HhrDD3ja2BilOp/q9xebohgcXg=; b=f3GICh9k5x9pqlwbRdWHOHb/J95cvoj8lxW8cNLwnjgN6YPn30CTo1DdQp0hSv2zlxmpU+ JxZ01pky6AlmugEzV7NlbQcl/yyvcCurRWlbUQ6Gx6cxr0l52oK9sIKs6Cjjtk8Qkrmszj puTpLekngftv3FaV3PBN2zq/jwHsmVw= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id B25FB600C8; Thu, 10 Sep 2026 09:21:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CE2DF1F000FF; Thu, 10 Sep 2026 09:21:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789032097; bh=etegQPhHDYYXKpgN5HhrDD3ja2BilOp/q9xebohgcXg=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=SWenu4/bhQp/ebHqQ47mZ8ttape8v/6aPUf2kjB/Ld/j9zBiWoVDmMFM2WXUeFpA4 Tz4kQl6h6D02ibEHqRfMCGmzm4F4W385fd4iPw4EV/b0R7FrEPUyPOdgqYghnwGSlg wlCNkIv6fYWAYcTfK4O6DgrRMLRvCHdb42c6Z5fPxcblq5pU74lnZfaSijO4QJtgql XWi5JzunvwkhvBE8/kV9Y4Q9psgLSZ8fOLaxugK+zflWpyfdSLe5ID2gv+8YzALlTs DNEG/urmvrS21JPGf+b18of+CcOKc6HBFiQHYWy3kARa8VmrNDWDGEakhoATI6H2NQ gKLgojcgqTT1g== Date: Thu, 10 Sep 2026 11:21:34 +0200 From: Thierry Reding To: Christoph Hellwig Cc: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Hunter , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Sowjanya Komatineni , Luca Ceresoli , Mikko Perttunen , Yury Norov , Rasmus Villemoes , Russell King , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Marek Szyprowski , Robin Murphy , Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , Christian =?utf-8?B?S8O2bmln?= , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Catalin Marinas , Will Deacon , Chun Ng , Mark Rutland , Saravana Kannan , Thierry Reding , devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux.dev, linaro-mm-sig@lists.linaro.org, linux-trace-kernel@vger.kernel.org, Thierry Reding Subject: Re: [PATCH v6 04/12] arm64/mm: Export set_direct_map_*_noflush() APIs Message-ID: References: <20260904-tegra-vpr-v6-0-79042cfa8de5@nvidia.com> <20260904-tegra-vpr-v6-4-79042cfa8de5@nvidia.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="nc5ni6zymi4hrk6h" Content-Disposition: inline In-Reply-To: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 4077FC0008 X-Stat-Signature: 9utgqo3epw7bi3jjwwrrhcdxyz43xcsy X-Rspam-User: X-HE-Tag: 1789032098-252905 X-HE-Meta: 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 FcFlYy/2 8wPppFMKKNN2oH05ORWX0fnVaSE1U0azcYMHV7W+p7pf4sLvFuJhqLRwtGp3E4t15h6L6nYdtlRDQr3kbLFqvjhJ4PmUchcYCFUtdOnooAS8mwmLIHM0Q/v44dePNFAfQ20wrIYdMvfzNKqVn/NUFcRoqWcmGPbivP3fx59xAFTdR34oAGblgGDOwXwYHDoJxcKy/Vk6gqy5TaeyHvKiifesehWP5kaji/tuEsIeahHvEEKimPwaKcZ1QGuBiIBuItZhyJBrJaH2+Cvd+G7gwobt2TjMM8lEqJlpE0mpUWf/jlqILtOk2IraiO5BPoLH3SqQyTrQLPWeE++FkaVCNGHlRoF81wrLLZ9A7yTjlCWtvBv3QEQl9ISqe++Oc7JHNDa6WH8PbNC90kaWY6mFJOoATRQXK42iwh7pEUxUToT20HtW379JQmx0srQVjslSVoJTSARNsm/pbZ6Gkaez9srJsMpa5vt8fvyHq26CtIMsGaQHTu7mE2kzZxsuC7bwOniVpeQLvrHmV4X3mC437ImNvHw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: --nc5ni6zymi4hrk6h Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH v6 04/12] arm64/mm: Export set_direct_map_*_noflush() APIs MIME-Version: 1.0 On Wed, Sep 09, 2026 at 10:51:43PM -0700, Christoph Hellwig wrote: > On Fri, Sep 04, 2026 at 12:44:55PM +0200, Thierry Reding wrote: > > From: Thierry Reding > >=20 > > Drivers that use this may want to be built as a module, so export them. >=20 > That's one of the worst commit log ever. No, we don't just export > core symbols dealing with the kernel direct map because > "Drivers that use this may want to be built as a module". >=20 > For one exporting this at all needs a very good justification and > not just hand waiving. But more importantly if we can't avoid > exporting it, it needs to be exported at the tightest sensible > scope. E.g. for a given module if it is so special, or a namespace > if it's not that special. But in doubt we should have a proper > core abstraction instead of opening up direct map manipulation to > random modules. Fair points. In an earlier set of patches this was abstracted behind a set of set_memory_*() functions, modelled after set_memory_encrypted() and set_memory_decrypted(), which I think I'd still prefer, too. Is that more along the lines of what you had in mind? 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