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 5F448CD6E4A for ; Tue, 2 Jun 2026 12:06:00 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C72A86B03C6; Tue, 2 Jun 2026 08:05:59 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C23ED6B03C7; Tue, 2 Jun 2026 08:05:59 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id B127A6B03C9; Tue, 2 Jun 2026 08:05:59 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0016.hostedemail.com [216.40.44.16]) by kanga.kvack.org (Postfix) with ESMTP id 9F9D96B03C6 for ; Tue, 2 Jun 2026 08:05:59 -0400 (EDT) Received: from smtpin22.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 508701C0ADE for ; Tue, 2 Jun 2026 12:05:59 +0000 (UTC) X-FDA: 84834844038.22.ADBC7D4 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf02.hostedemail.com (Postfix) with ESMTP id 6292880011 for ; Tue, 2 Jun 2026 12:05:57 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=Amo5lWUb; spf=pass (imf02.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@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=1780401957; 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:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=0rBNmQTDKcWgn1oObpixLuWnRYTldupbgDAPBU/n0Rk=; b=8kpF08723pb7qQgnDteQPrzhD9eo0VL3LyyB7Kb31RzQOdEwwT334QddK/+LHotuMtru6Z Ig381qZnWAoPi2Tbd4GTNNsMdFbWAiIKFjD4l2xND8k32okpfC0Am8xYpn8DIgErywbzDZ O4K83dkltMFmLHMsZmyt6+gAVrJqums= ARC-Authentication-Results: i=1; imf02.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=Amo5lWUb; spf=pass (imf02.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@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=1780401957; b=LK7gS1YYcDlOGVZO7cGrKeT4gWnH6uCgeAJ/hgYZVAEjWW5joDBIUTUWk5g69RK15I0WOU xgI0LXX2YkZdzTt7MRyLAELjHbi9yuXISNKxHpcJOP+JLsWBIhgVd3wJqbDee6HHzOvLoU lilWZ7BzH+SCg6tn5GLVqvC2im0N638= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 52A6643607; Tue, 2 Jun 2026 12:05:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A170A1F00893; Tue, 2 Jun 2026 12:05:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780401956; bh=0rBNmQTDKcWgn1oObpixLuWnRYTldupbgDAPBU/n0Rk=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Amo5lWUby9SawGFQ8No7VSEZsFiPxSj5m2OfYruCYVq3s/uRBYbaCkiXWkqYXCVtQ G995pxnNeaB+xoogXGEKPl0Ks7hMaowdBP3Wf68WwyeRAZxPZhr/OcRjfcX6l4TX4K uTTfQnL98J32ccApLKowF6+5uMAfCieS9sqPp1d+oNd+AkY+CtaxVR9zriRKhaM3d8 +fRUzpwzaPPTKybMbEfMfAMTBIwrLE0PlykGMFNTc/Q9GpWgBkgQSfobauimVfuY32 NRb2KNo4YQ93IEtqnG53cj5Vw55UnJus60mdKn7B7/CIfsuX6Q10ye6MeOqjJIpI1Z 0YPjgnT/UOSJQ== Message-ID: <56c9fc17-685e-429f-832a-964f28b9dd4f@kernel.org> Date: Tue, 2 Jun 2026 14:05:52 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 3/3] mm/vma: eliminate mmap_action->error_hook, introduce error_override To: Lorenzo Stoakes , Andrew Morton Cc: Arnd Bergmann , Greg Kroah-Hartman , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <55d13f7d016b827c459946d46a56105635be111c.1780397980.git.ljs@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <55d13f7d016b827c459946d46a56105635be111c.1780397980.git.ljs@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 6292880011 X-Stat-Signature: q6f9nqxo4h43gaf56uwx84i6f99tqf16 X-Rspam-User: X-HE-Tag: 1780401957-278322 X-HE-Meta: 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 2nhdzSiU bOfoIpZAieoF4+ql/6+jcE9+JtgCNAxpDqXSK9Kj1JegSF0XoAj8x3zIRSe6H0lrfKOVpkk8S3gW+i2zlT9MTp59tXXVcCndzxs9w0WuGVbITu8mgdfKSIAIRObjn8PKNtppFPMR2W904tw1e9Ekakx0G038lAeSqHFqvMfOmRaKjXSg7A9h0ozAUk4aFMydVu41sKXjQJC7LgspksEL5zV2EMstHDswaT4RSq9GuNJDkVDdGo/xIN/WfVIuo2PDsgAOSrVoZIKmOwezOTsO1sC8V1L83OizgCAR5wpWjd2uqXAuY9Bw18cCEBz+oWLXNae3yztWkcFcvkIU= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/2/26 13:06, Lorenzo Stoakes wrote: > Rather than providing a hook, simplify things by providing the ability to > override mmap action errors. This allows us to more carefully validate the > value provided and thus ensure only a valid error code is specified, and > simplifies the interface. > > This way, we eliminate all hooks but mmap_prepare and allow only mmap > actions to be specified (which core mm controls). > > This significantly improves robustness and eliminates any unnecessary code > duplication in driver mmap hooks. > > We also update the /dev/mem logic (the only user) to use > mmap_action->error_override instead. Thanks! Acked-by: David Hildenbrand (Arm) -- Cheers, David