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 BA80CC55184 for ; Mon, 3 Aug 2026 13:52:59 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9D6E46B00BB; Mon, 3 Aug 2026 09:52:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 987006B00BF; Mon, 3 Aug 2026 09:52:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 800EF6B00C0; Mon, 3 Aug 2026 09:52:57 -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 55E886B00BB for ; Mon, 3 Aug 2026 09:52:57 -0400 (EDT) Received: from smtpin25.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 8F00D1A0690 for ; Mon, 3 Aug 2026 10:15:32 +0000 (UTC) X-FDA: 85059551304.25.5739E0E Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf20.hostedemail.com (Postfix) with ESMTP id DDEC51C0007 for ; Mon, 3 Aug 2026 10:15:30 +0000 (UTC) Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=J2TVK2uX; spf=pass (imf20.hostedemail.com: domain of ljs@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=ljs@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=1785752130; 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=v71BYkAHIRI8Q8frz24K9WW9baJGdIZiJra6zVG9U4Q=; b=123nhwR5QJ9+DResMTibdYwD9gRLRIVgms2yvbATob07jctJnCfL0f2sHomoE7SiV6d/PZ ISXnLtwmvea948ONefH6aFGGQxJ+ko6JDLniS9Oax7eRRDVM833pVO7pGxSaHSw2/sgWRd gG09bEa2Pqu4LLsIgL6RU5Z/SAzj/RI= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1785752130; b=bcQmDVSK6zcxr3ngXrHxPcB0pXEj8Z9UuvFqUfCNK5bcxbSuYMzmeepqyGlbeVlN25tseB E/Qy5+ayMIrl24zYP8lUwjqF72OAHM0CNvWwhS8QNl/+NJ6pRn4sXLhNs/NQXDgO69t3cP SrfPnfnloSJwPYye0jStwWcPrPeKwic= ARC-Authentication-Results: i=1; imf20.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=J2TVK2uX; spf=pass (imf20.hostedemail.com: domain of ljs@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=ljs@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 0926F40344; Mon, 3 Aug 2026 10:15:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 747321F00A3D; Mon, 3 Aug 2026 10:15:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785752129; bh=v71BYkAHIRI8Q8frz24K9WW9baJGdIZiJra6zVG9U4Q=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=J2TVK2uXiY0cFJv633nAghYxOTtWj4WoRxazTyou1qgggoZymwvopm2LYCBg2kGds ymnEUF629L7pEfyiNWowUOOSJQuuFRFGV0mUPgZhuLD0CLW+vIr6c7Geq2Pma137YW 7OE4bzALZg01VNZS4/a6HHR0z4/2doG6N70QflXd/8HfBF5LxlbDxZHougZiJEavRk UPdaWF+jiInQXa4aETFFy0RaM5skKQ+gkvmOLWR3CfSgtF+rR82OhQEep61xeS09aB dz9eVzhUmkqmOXcqJfvphbCw7TqLCjh3jYOIQtdjIp2vHvzAJ8qyVFEMto2DgiH17d n2cE1J7UNfRQw== Date: Mon, 3 Aug 2026 11:15:08 +0100 From: "Lorenzo Stoakes (ARM)" To: "David Hildenbrand (Arm)" Cc: Andrew Morton , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , "Matthew Wilcox (Oracle)" , Jan Kara , Miaohe Lin , Naoya Horiguchi , Rik van Riel , Harry Yoo , Lance Yang , Kees Cook , Zi Yan , Baolin Wang , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Usama Arif , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Peter Xu , Xu Xin , Chengming Zhou , Arnd Bergmann , Greg Kroah-Hartman , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v3 05/15] mm: introduce and use vma_filebacked_address() Message-ID: References: <20260729-b4-scalable-cow-virt-pgoff-v3-0-e8ecfefea812@kernel.org> <20260729-b4-scalable-cow-virt-pgoff-v3-5-e8ecfefea812@kernel.org> <73adddc9-4321-4f6d-ac67-470c8f515fff@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <73adddc9-4321-4f6d-ac67-470c8f515fff@kernel.org> X-Rspam-User: X-Rspamd-Server: rspam09 X-Rspamd-Queue-Id: DDEC51C0007 X-Stat-Signature: eug34kzzb3u8tqgfao33nezezeiamddz X-HE-Tag: 1785752130-530430 X-HE-Meta: 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 zVE3hIRG +Pizsgd05yL2X650cMjulUqk9OiE3O+e2MgwCBOfoWUGXIE6xzW5bDiG4rbf+oyCKMiA+ZPfkBNv86xb4ZT7xLPfq86NMmXJ60wWyLaEi5Sfv22NvAykwdqkHckUZSShzShkX6s0wtr8wBTjnIr+8uQA4zohm/6OND5PNUSm4paqte4/7+jA3s+ubWV9MwytjWssQyB9p/atrMcQeJOKt0YEeD5mdWGr/m+3RDFlxRRbL2nWuUT7ewbkwasC7kMZOpod73B0FYpB/4h9I/awAXheibJM4UccGrpf7GWc4nPwGBnCLRyzjlm7LisBOqlxSgXVvVswNzQzYZi5+JY2kSQs5KjqtK/LHCxecqUzUghzX/YB1LcfH8WjKrAUAi6FaktXfd31ROElLPCrdXrDAiWGuuw== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Mon, Aug 03, 2026 at 11:54:31AM +0200, David Hildenbrand (Arm) wrote: > On 7/29/26 18:48, Lorenzo Stoakes (ARM) wrote: > > In cases where we know that the VMA is file-backed, use > > vma_filebacked_address() rather than vma_address(). > > > > This lays the foundation for using the anonymous page offset via > > vma_anon_address(). > > I was briefly confused why we can't do that immediately. Because everything has to be switched on at once or it breaks things. Obviously you could use vma_anon_address() for pure anon but at that point you're only confusing things. This all stems from the existing situation where anon folios might be indexed by EITHER a file offset or an anon offset. In the end 'laying the foundations' makes the actual 'switch it on' patch (9/15) nice and (relatively) small :) > > > > > Also add an assert to ensure that the VMA whose address is required is not > > anonymous. > Acked-by: David Hildenbrand (Arm) Thanks! > > -- > Cheers, > > David -- Cheers, Lorenzo