From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 37262606A327 for ; Tue, 27 Oct 2026 00:12:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=g61CasbH; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lZtXD8ew DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Date: Content-Transfer-Encoding:Content-Type:References:In-Reply-To:Cc:To:Subject: From:Message-ID:MIME-Version:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Unsubscribe-Post:List-Owner; bh=ZqEdHj9SpWceidheOE1bPXmyrnympSvqGH0UJxfFWnA=; b=g61CasbH+wrXQdIOMpH2ftZT/f /aSV2dAfQLHCNm03F9MWNl4WglIVjmeZ4OIM4qX0KK6zg2plz/VdOYiw9lEbdSUs7pX24a8AiG+cf v3cl6v2bLOfta7qJwIJGRNFJQ9zhCqNifaglf3HWguGjd/xVJsi5L/tPdZeWGOG456se+UnhvTKtN YeiSs5uF+7heinwI9mtZ269+yf78mCFKTa09Ms/cm7SymYg4SLuhpy0aKMs/GmYXCvcF6LX66msAj XusTf/d4qkACzL+0m0x1pH7jsA91IivhTwsBGKJIZ7ZOzQzxSBKf6Z6m236KbKZ/gIP4YSzh1S4ER yyHVipNQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLUnp-00000003UrO-3ms3; Tue, 27 Oct 2026 00:12:33 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xLUno-00000003Uqj-3dQI for kexec@lists.infradead.org; Tue, 27 Oct 2026 00:12:32 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 4D413600CB; Tue, 27 Oct 2026 00:12:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7C45B1F01825; Tue, 27 Oct 2026 00:12:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793059952; bh=ZqEdHj9SpWceidheOE1bPXmyrnympSvqGH0UJxfFWnA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=lZtXD8ewPZmu2QxDYUP3TcpKcra95u/e0/eq5iaLDP1spV21Qb3sDgBeEo0kOSIu7 HSlysKPS4mZhbsnhs3iDgSPdQj0t+mxiQJj76j4jNe9P+iICCuhS+mbO2L2yaDeoCi hp3eO6ZkA5KE3vszFL5uC1QvqffhGPzxj1DPhHWpVOUDikAqOX+3/Ta0cFRzBx8A61 Gs0iTfp/tJbY8CS6r3GCLmeJszLjWuSwnm8GVI0Rb5Y2s+DWINF5RXII44P0jMbHpw KlZr7s7g4IOc4516eEzfYMALpzmGrQQ51fkMO4xUV4PbJoUNgEx+cZ10ydIXhx2hGS UVSWaxV8Qk3BA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 09/46] mm/rmap: handle device-exclusive entries in folio_referenced_one() To: =?utf-8?b?RGF2aWQgSGlsZGVuYnJhbmQgKEFybSk=?= , "Andrew Morton" , "Johannes Weiner" , "Michal Hocko" , "Qi Zheng" , "Shakeel Butt" , "Lorenzo Stoakes" , "Kairui Song" , "Barry Song" , "Axel Rasmussen" , "Yuanchu Xie" , "Wei Xu" , "Baoquan He" , "Baolin Wang" , "Liam R. Howlett" , "Vlastimil Babka" , "Mike Rapoport" , "Suren Baghdasaryan" , "Michal Hocko" , "Kees Cook" , "Peter Zijlstra" , "Jann Horn" , "Pedro Falcato" , "Hugh Dickins" , "Pasha Tatashin" , "Pratyush Yadav" , =?utf-8?b?TWF0dGhldyBXaWxjb3ggKE9yYWNsZSk=?= , "Jan Kara" , "Zi Yan" , "Lance Yang" , "Rik van Riel" , "Harry Yoo" , "Alistair Popple" , "Nico Pache" , "Ryan Roberts" , "Dev Jain" , "Usama Arif" , "Kiryl Shutsemau" , "Matthew Brost" , "John Hubbard" , "Peter Xu" , "Will Deacon" , "Aneesh Kumar K.V" , "Nick Piggin" , "Oscar Salvador" , "Minchan Kim" , "Muchun Song" , "Xu Xin" , "Chengming Zhou" , "Chris Li" , "Kemeng Shi" , "Nhat Pham" , "Youngjun Park" , "Gregory Price" , "Joshua Hahn" , "Rakie Kim" , "Ying Huang" , "Jason Gunthorpe" Cc: kexec@lists.infradead.org, "Josef Bacik" In-Reply-To: <20261027-fixes_core-v1-9-6f74bec9a5bb@kernel.org> References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-9-6f74bec9a5bb@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 27 Oct 2026 00:12:29 +0000 X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Sender: "kexec" X-Spam-Status: No, score=-11.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 X-Archived-By: > page_vma_mapped_walk() can return non-present device-exclusive entries, > but folio_referenced_one() passes them to PTE young-bit accessors that > require present PTEs. >=20 > We must neither call clear_flush_young_ptes_notify() nor > folio_pte_batch() with non-present entries. For example, clearing the > young bit on non-present PTEs can corrupt the entry: on arm64 > PTE_AF overlaps the swap type, so clearing it turns a device-exclusive > entry into an ordinary swap entry. >=20 > folio_pte_batch() will VM_WARN_ON_FOLIO. >=20 > Apply the same approach as the previous fixes to e.g., damon_ptep_mkold(): > treat these entries as old from the CPU's perspective and obtain their > young state through the MMU notifier. >=20 > Skip PTE batching and MGLRU look-around for non-present entries, and > don't modify non-present PTEs. >=20 > Fixes: b756a3b5e7ea ("mm: device exclusive memory access") > Reviewed-by: Lorenzo Stoakes (ARM) > Cc: stable@vger.kernel.org > Reported-by: Josef Bacik > Signed-off-by: David Hildenbrand (Arm) Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261027-fixes_core= -v1-0-6f74bec9a5bb@kernel.org?part=3D9