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 1887D606A31B for ; Tue, 27 Oct 2026 16:27:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=Te/hFcTC; dkim=pass header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=Hg+twqpr; dkim=pass (1024-bit key) header.d=suse.de header.i=@suse.de header.a=rsa-sha256 header.s=susede2_rsa header.b=Te/hFcTC; dkim=neutral header.d=suse.de header.i=@suse.de header.a=ed25519-sha256 header.s=susede2_ed25519 header.b=Hg+twqpr Received: by kanga.kvack.org (Postfix) id 10F766B0833; Tue, 27 Oct 2026 12:27:50 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0C0636B0835; Tue, 27 Oct 2026 12:27:50 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EA30F6B0836; Tue, 27 Oct 2026 12:27:49 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id BBE896B0833 for ; Tue, 27 Oct 2026 12:27:49 -0400 (EDT) Received: from smtpin29.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 118D8C0A7D for ; Tue, 27 Oct 2026 16:27:49 +0000 (UTC) X-FDA: 85368937458.29.E8025A7 Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.223.131]) by imf23.hostedemail.com (Postfix) with ESMTP id D590E140005 for ; Tue, 27 Oct 2026 16:27:46 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b="Te/hFcTC"; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=Hg+twqpr; dkim=pass header.d=suse.de header.s=susede2_rsa header.b="Te/hFcTC"; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=Hg+twqpr; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf23.hostedemail.com: domain of pfalcato@suse.de designates 195.135.223.131 as permitted sender) smtp.mailfrom=pfalcato@suse.de ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1793118467; 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=/itwoJPNV/PYjgH1tW8TC7VQ2qoANM6I5XSJVpUiq8M=; b=gXfwTn3EW95WU6q1gM8Gw1sLjy9/iipRRaKwUHnvWC7NvjviNPePXAUdf1/iedMySPPmgU ch5euQ6hOprZjZRtkUGOSSkXdOxf+DCvDfU9z4445YQWOeM8WtgW9VtC2uPHFn2LTnMCgg uMjjDDJm7d0krRWO+58P/oTx9MGAWGk= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=suse.de header.s=susede2_rsa header.b="Te/hFcTC"; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=Hg+twqpr; dkim=pass header.d=suse.de header.s=susede2_rsa header.b="Te/hFcTC"; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=Hg+twqpr; dmarc=pass (policy=none) header.from=suse.de; spf=pass (imf23.hostedemail.com: domain of pfalcato@suse.de designates 195.135.223.131 as permitted sender) smtp.mailfrom=pfalcato@suse.de ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1793118467; b=SR0jRz8imWxvIw38ds58z00i1R3zB24QLlIEit/pUUJUHZKuvgesGQYoNKDJfT7s0K//y1 qxkmlAnJl75cUDRTHA4Z6l6VszSToF+q2gTTPrNDImoY2fw83/sDMOFCgwy/vs06+zEn3y muTGVXepz6IdBEZ10Sdxux/C4GvOoMk= Received: from imap1.dmz-prg2.suse.org (unknown [10.150.64.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id B26F21F7E9; Tue, 27 Oct 2026 16:27:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1793118465; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/itwoJPNV/PYjgH1tW8TC7VQ2qoANM6I5XSJVpUiq8M=; b=Te/hFcTCOKkoMgRX5zaqYIVBggY9Fpr20ezr2tFqxNsXOnKsbQwUmmdTdAciG+uCQTDjth dVktrGDfybLq8FuT/n1SiYOTAsUYVXG9Sing0oS69R2+Iytv0Z/Y7lJYjwwMTzhsktO6j4 fMoJAX/MIJCIH+SrJ4jkjDxdxSCgPWE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1793118465; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/itwoJPNV/PYjgH1tW8TC7VQ2qoANM6I5XSJVpUiq8M=; b=Hg+twqprF0ocwkjIQM9VGipaZPJ1m+OpmAD+rhXe3by6Gq2PHVtPT9ufjbMIV82PfR4N4K l27dUCgkPKJmAnBA== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1793118465; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/itwoJPNV/PYjgH1tW8TC7VQ2qoANM6I5XSJVpUiq8M=; b=Te/hFcTCOKkoMgRX5zaqYIVBggY9Fpr20ezr2tFqxNsXOnKsbQwUmmdTdAciG+uCQTDjth dVktrGDfybLq8FuT/n1SiYOTAsUYVXG9Sing0oS69R2+Iytv0Z/Y7lJYjwwMTzhsktO6j4 fMoJAX/MIJCIH+SrJ4jkjDxdxSCgPWE= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1793118465; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=/itwoJPNV/PYjgH1tW8TC7VQ2qoANM6I5XSJVpUiq8M=; b=Hg+twqprF0ocwkjIQM9VGipaZPJ1m+OpmAD+rhXe3by6Gq2PHVtPT9ufjbMIV82PfR4N4K l27dUCgkPKJmAnBA== Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id A1EA61321C; Tue, 27 Oct 2026 16:27:41 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id BayYG/3Q4GpDBwAAD6G6ig (envelope-from ); Tue, 27 Oct 2026 16:27:41 +0000 Date: Tue, 27 Oct 2026 16:27:39 +0000 From: Pedro Falcato To: "David Hildenbrand (Arm)" Cc: 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 , Hugh Dickins , Pasha Tatashin , Pratyush Yadav , "Matthew Wilcox (Oracle)" , 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 , linux-mm@kvack.org, linux-kernel@vger.kernel.org, kexec@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-cxl@vger.kernel.org, Josef Bacik , stable@vger.kernel.org Subject: Re: [PATCH 35/46] mm: fix unmap_mapping_range() beyond 4 GiB on 32-bit Message-ID: References: <20261027-fixes_core-v1-0-6f74bec9a5bb@kernel.org> <20261027-fixes_core-v1-35-6f74bec9a5bb@kernel.org> X-Archived-By: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261027-fixes_core-v1-35-6f74bec9a5bb@kernel.org> X-Spam-Score: -11.80 X-Spam-Level: X-Rspamd-Queue-Id: D590E140005 X-Stat-Signature: shoh7cniofizdcjfoat85yhee6qxgqfz X-Spam-Status: No, score=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=unavailable autolearn_force=no version=4.0.1 X-Rspam-User: X-Rspamd-Server: rspam09 X-HE-Tag: 1793118466-132134 X-HE-Meta: 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 42HEnH6j ww4CSifTe8R2wTeTFqjXlxYsBuQykR4bU8l6vwuNJOfsjukUkNLfPLoWNfS7TnwcOpHC9AKxeqgl3YwGn344zzBuPz5ovTcXyZJpqW69A4nQXqH1osSEdsTFnNg3a9VvA1lz4OXF1VrTOddo9JsL0GwxuI8MGgwKHNAdUk3YC7rM7YsptYUjO2wmhX8NdOQ/dPP9iwqgrvGjTOj+Ct40lwg+Q33Z8SH9XPOVeBYw9he0ftrLWbbp/6oxTiMC3FbMvqk5BcruR18sSK19pbSMC1+bc0LPojsoByDqLXrEws1v9tDt0BdBWJkZsX7T8i3IQsMclkqeA5U0zdgFMRkqkl/fBYoC/sJtQpkHCB3JxQNeUHsD3W6+SvhYBDE+rengz36odlFv161H0m+GN54yV1CXPtn88BmwM6bWE1cemAZnu/W4w4EOMc1++vIFkBA7RzQSCX1QfdqG21RSjS4Rb4u6qSA== 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 Tue, Oct 27, 2026 at 12:17:55AM +0100, David Hildenbrand (Arm) wrote: > From: Josef Bacik > > Commit 9eab0421fa94 ("mm: fix unmap_mapping_range high bits shift bug") > made holebegin and holelen unsigned before they are shifted, by casting > them to pgoff_t. That is an unsigned long: on a 32-bit kernel the cast > cuts off the upper half of the two loff_t values, so a hole which begins > at 4 GiB or beyond is taken for one in the first 4 GiB of the file. > > truncate_pagecache() passes the new size of the file and asks for private > COWed pages to be unmapped as well. If a file of 6 GiB is truncated to > 5 GiB, everything from 1 GiB on is unmapped, and what a process has > written to a private mapping of the range between 1 GiB and 5 GiB is > lost: it reads the contents of the file again. > > Where the range has an end, the wrong range is unmapped instead of the > right one. The page cache copes with that, as it unmaps every folio that > it removes. The callers which only have unmap_mapping_range() to get > rid of user mappings do not, for example drm_vma_node_unmap(), whose fake > offsets reach beyond 4 GiB on 32-bit, and revoke_iomem() with physical > addresses of more than 32 bits. > > Cast to u64 instead. Nothing changes for 64-bit kernels. > > Fix generated by an LLM and sent by Josef Bacik in private. > > Fixes: 9eab0421fa94 ("mm: fix unmap_mapping_range high bits shift bug") > Cc: stable@vger.kernel.org > Signed-off-by: Josef Bacik > Acked-by: Lorenzo Stoakes (ARM) > Signed-off-by: David Hildenbrand (Arm) Reviewed-by: Pedro Falcato -- Pedro