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 4B9F1C5DF9C for ; Tue, 25 Aug 2026 05:57:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 318C16B008C; Tue, 25 Aug 2026 01:57:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2C9C16B0092; Tue, 25 Aug 2026 01:57:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1B8556B0095; Tue, 25 Aug 2026 01:57:14 -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 E84E96B008C for ; Tue, 25 Aug 2026 01:57:13 -0400 (EDT) Received: from smtpin01.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay09.hostedemail.com (Postfix) with ESMTP id A5FFB802D2 for ; Tue, 25 Aug 2026 05:57:11 +0000 (UTC) X-FDA: 85138733862.01.1DA0CB5 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf17.hostedemail.com (Postfix) with ESMTP id 4FCCF40003 for ; Tue, 25 Aug 2026 05:57:09 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=4hivPyVH; spf=none (imf17.hostedemail.com: domain of BATV+b87911c0b4807dbed12c+8402+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+b87911c0b4807dbed12c+8402+infradead.org+hch@bombadil.srs.infradead.org; dmarc=pass (policy=none) header.from=infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1787637430; 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=3n8sKxOLY9bY1Jljt7EDfRL2ryQR3dKEADtbegGl4j4=; b=sPlBlCNyqVbnbHKxP0dixv7B+OhxAPGOb7zXkxzlqXO5Qp6M9atmn4TvtSHtEYoHnUlNxC JY2wUwLKZ39boPagbcrHFOikez76JlB6rsCzaVLcQdH+4/stXmyKLQNhJbRYRN/rig8Lol qUzXB6pkrbWL2k/LF5Wcc5/gc/4csYo= ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1787637430; b=ZZfXAcxrmM0wOjom6Qa54PfrEfsZy7V+qLMMZOk/gpo2WYHhsoTwWQmoWHYBBmcBI+oZEq lRBfZSyQXNtbVT6jfBTxKHE1XJchXn+n19GSe2b92pEuzn+4haZjpnkzhcpidKj9kcA3Zz w+MUNUDcwZVps5XkxLJT6nFNR9yRY/E= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=4hivPyVH; spf=none (imf17.hostedemail.com: domain of BATV+b87911c0b4807dbed12c+8402+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+b87911c0b4807dbed12c+8402+infradead.org+hch@bombadil.srs.infradead.org; dmarc=pass (policy=none) header.from=infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=3n8sKxOLY9bY1Jljt7EDfRL2ryQR3dKEADtbegGl4j4=; b=4hivPyVH/E7aqxa198tsBYDhtT pheZRlehn97+Pn+qzZaamy4FMBMqTsG+w+pkWof61SjtSa9zehOQ74t1NrJjVEf9r/JJsmeqJyLa9 fBTbTLLiYWmmi3cTiTHnpobC+AzmGunnKistH6FS80+HKogiTyOLdD1uCZEHaPATXdecv2Y3kzsNb /EBYP+I/hoJIhzQU4bobyba03Nfl/g65gyYRW0qqrdo2uJn8rvlut1397NlYgCBj9E6dLPWjKUzJg MUKlmO/qw1j5IIU9m55sC1Y4+KFkL4YbVaa1aXZC1jyurhvheXv+3OzXzdThqJMPuoxtd6icvr+DD 05wedv1Q==; Received: from hch by bombadil.infradead.org with local (Exim 4.99.1 #2 (Red Hat Linux)) id 1wyk9d-00000000Cqf-15be; Tue, 25 Aug 2026 05:57:01 +0000 Date: Mon, 24 Aug 2026 22:57:01 -0700 From: Christoph Hellwig To: Lance Yang Cc: pfalcato@suse.de, kas@kernel.org, usama.arif@linux.dev, hughd@google.com, akpm@linux-foundation.org, baohua@kernel.org, baolin.wang@linux.alibaba.com, david@kernel.org, dev.jain@arm.com, liam@infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ljs@kernel.org, nico.pache@linux.dev, ryan.roberts@arm.com, ziy@nvidia.com, nphamcs@gmail.com, hannes@cmpxchg.org, riel@surriel.com, shakeel.butt@linux.dev, kernel-team@meta.com, stable@vger.kernel.org Subject: Re: [PATCH] mm/huge_memory: transfer the pmd dirty bit to the folio on zap Message-ID: References: <20260820061337.24669-1-lance.yang@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260820061337.24669-1-lance.yang@linux.dev> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Rspam-User: X-Stat-Signature: 7ei811xxjf81r6mwre61mfgwud5ug1oh X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 4FCCF40003 X-HE-Tag: 1787637429-192274 X-HE-Meta: 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 pXdoYUTJ 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Aug 20, 2026 at 02:13:37PM +0800, Lance Yang wrote: > XFS installs the huge-fault, regular-fault, and page_mkwrite callbacks > in the same vm_ops: > > static const struct vm_operations_struct xfs_file_vm_ops = { > .fault = xfs_filemap_fault, > .huge_fault = xfs_filemap_huge_fault, > ... > .page_mkwrite = xfs_filemap_page_mkwrite, > ... > }; > > On the fallback path, handle_pte_fault() leaves an empty PMD without a > PTE and calls do_pte_missing(): Just a reminder that it would be extremely helpful if we could refactor the vm_operations_struct so that file systems could register one single fault handler to cover all these (plus .pfn_mkwrite) to remove all the annoying boilerplate code in the file system and the confusing fallback logic in the VM.