From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 63F56606A31E for ; Thu, 29 Oct 2026 15:47:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=kPqVAAGG Received: by kanga.kvack.org (Postfix) id 362C46B05D1; Thu, 29 Oct 2026 11:47:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 33B566B05D3; Thu, 29 Oct 2026 11:47:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 251D36B05D4; Thu, 29 Oct 2026 11:47:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id E66336B05D1 for ; Thu, 29 Oct 2026 11:47:39 -0400 (EDT) Received: from smtpin30.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 547E11C3BF3 for ; Thu, 29 Oct 2026 15:47:39 +0000 (UTC) X-FDA: 85376093838.30.50FA483 Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf10.hostedemail.com (Postfix) with ESMTP id 90B12C000D for ; Thu, 29 Oct 2026 15:47:37 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=kPqVAAGG; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793288857; 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=HsTZsAbnOjm+7kjd0LiVGLSB693ohnd2liVr1NWALdI=; b=VhUuQQceqITYOnLcoD91/z7eAXpKyjIqDlB8xZugImyMqbJWiyL0LCuLoS2BpXykMVCZLV UfVwjN87mCMgKlRYqzsWKUJ/S6OCdOIjEE/PO1ss8qva0aPD4qF+g2jE3ZVAw6q13+ZNqZ rNDihISfmFi9SK7EzBaP29NO5REuuOQ= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=kPqVAAGG; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf10.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793288857; b=LtcoYRlV9d2gbbAQvf8CI9LzyGq+76viTJJAgRTy0n55BTOn7kw6aaLYH+lNCYqFhp2nxE JSdp/IF99qJ1Husszf74xAE5gv0WeSxGGbmexLy8CABNDN2PhtwtUNihEy/NLdk8cRVBUA wZ++D+KdxcZ5zttpvEUB44dT708i0Qg= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 182B8600E4; Thu, 29 Oct 2026 15:47:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 07E841F01816; Thu, 29 Oct 2026 15:47:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793288856; bh=HsTZsAbnOjm+7kjd0LiVGLSB693ohnd2liVr1NWALdI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=kPqVAAGGkIKCU4DgEa4KGASh5IaaZBYjqWTq8XXVIa2i/LXmgfr65nhEbZis9yLma pi+jmXTUv47DsPxG5kbv5ThaOO4ZlLdxrHX4IIntOTMKGQKCLEi1KT0KsW2aaKbMYN quxGwRm73ICAydKIZdyG6Yc/+WaA/T+MIXJEHERZhRSuAoMfziKFFnXtz3aTxIx6ME +AiXyBIDGlPd9SDiEiZs7Bschwl+ETBiEqz07BqCgYemmJVBOvU/LKGFSQ7cS28PJa kqALZQQJqId41hzON38xxvnBKlUS99Ty6/F5oGkcxqbh6ctiRNeSYjhXC+IyjeNF20 JW6QoFxOEj8/w== Message-ID: <3c141e6f-dd1d-4e48-bb9b-a94c0554d947@kernel.org> Date: Thu, 29 Oct 2026 16:37:23 +0100 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] mm/sparse: simplify the vmemmap alignment check To: Kiryl Shutsemau , Kaitao Cheng Cc: Andrew Morton , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Muchun Song , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Kaitao Cheng References: <20261029134521.62146-1-kaitao.cheng@linux.dev> 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 90B12C000D X-Rspam-User: X-Stat-Signature: m7e6ya58muqnw3ohs7f5y1ii639f4qzh X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=4.0.1 X-Rspamd-Server: rspam03 X-HE-Tag: 1793288857-953794 X-HE-Meta: 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 DlyjatZR AU0/NCrGqRVKKdW9VN5mrP9QJEf62EWuG9eeRexblUZU5VkY1JOQaaCdL19oF9E0hZWANLoJgSKCHB28vqdme0FxfofuS6kj/mW8n/KoV0FEmGhQs3aaAct+jU0AA4TtSRIYGDBdo29m4TKm4xGXLgpzUk9aLRMco+blT7YjyhVgC3R4TemmRPMKErSBUYDGn6M2GzNrvL5m5pitVlOvM+tgye4jEsqcO2vhL/Qzja8mLhjApUAA49T3eFbFMrb2fTOjr Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 10/29/26 15:44, Kiryl Shutsemau wrote: > On Thu, Oct 29, 2026 at 09:45:21PM +0800, Kaitao Cheng wrote: >> From: Kaitao Cheng >> >> sparse_init() is called only once during boot, and the vmemmap alignment >> check is outside any loop, so VM_WARN_ON_ONCE() provides no benefit over >> VM_WARN_ON() here. > > Okay, that's true. But who cares. __init section will be freed anyway. > I don't see downside in current code. > >> Use VM_WARN_ON() and fold compound_info_has_mask() into its condition, >> preserving short-circuit evaluation. > > Why? It only got harder to read, no? This would be fine as part of some bigger rework, but standalone this cleanup is not very attractive :) -- Cheers, David