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smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="aMjXyau/"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6A8D0606A31B; Mon, 26 Oct 2026 23:30:54 +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=aMjXyau/ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 55C791F01825; Mon, 26 Oct 2026 23:30:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793057454; bh=Q9qeqP7UIpC4jZdgK/RdXjrodSxtqhxIZFIMBK0dNEo=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=aMjXyau/DEsG4YEydgc7sLdZKV3j2+LW2b3eNS7X04Qc4ps76HV4VLUeqoLpSYofQ pNs1KkeKtqL5YsMBwS4HuHwBQgtJTMXc8b0J/LV7PC4ZEmv05CevPNCGlefvGzZzOq SBctlXL5N+6DWUb3QCKOqKJvp/XPk5b9g8EabmrImmA2AFBAHIQRb9BHaxfEWT6YJ5 Wy6SLfoIBnL2o30c+yyJiRVa2EZUQQPBFqVRbNK+Moy1vtqGht1vqXxe9x0SsIb3cw P+sIyiqcq0KQMpzIa7NPFpdKkz01A9vPZ3PEqp0zq+95N0LLvoKeE67Dw1xNIoyakq UBliE1LHD86vA== Message-ID: <2467500f-d72f-4b09-a049-e70fa3fcfb3b@kernel.org> Date: Tue, 27 Oct 2026 00:30:40 +0100 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 07/16] mm/shmem: avoid moving the truncation start backwards To: Zi Yan Cc: Andrew Morton , Zhang Yi , Gregory Price , Joshua Hahn , Rakie Kim , Ying Huang , Johannes Weiner , Vladimir Davydov , Michal Hocko , Hugh Dickins , Baolin Wang , Lukas Czerner , Carlos Maiolino , Christian Brauner , Jan Kara , Daniel Verkamp , Jeff Xu , Muchun Song , Oscar Salvador , David Stevens , "Matthew Wilcox (Oracle)" , William Kucharski , Chris Li , Kairui Song , Nhat Pham , Miaohe Lin , Naoya Horiguchi , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chris Mason , stable@vger.kernel.org References: <20261026-fixes_shmem-v1-0-703206d5fa0c@kernel.org> <20261026-fixes_shmem-v1-7-703206d5fa0c@kernel.org> <2E377C76-D62C-4A2A-94E3-ABC40C6FCDD2@nvidia.com> <583728ed-dc63-4685-9ac5-5a980db55973@kernel.org> <0D22B04E-5730-4D3A-ADA6-9F1AF94F06AA@nvidia.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit On 10/27/26 00:28, Zi Yan wrote: > On 26 Oct 2026, at 19:24, David Hildenbrand (Arm) wrote: > >> On 10/27/26 00:16, Zi Yan wrote: >>> >>> >>> To clarify the dependency, without Zhang Yi’s >>> truncate_inode_partial_folio() patchset, the ext4 + iomap changes >>> would cause data loss. We probably want to get Zhang Yi’s patches >>> in first to avoid that. >> >> Ugh, what a mess. >> >>> >>> Patch 7 to 11 do not apply cleanly on top of mm-stable due to Zhang Yi’s >>> truncate fix, where >>> >>> 1. patch 7 can be dropped as I discussed above, >>> 2. patch 8 needs a folio->mapping guard for the added statement, >>> 3. patch 9-11 can be applied with fuzzy, but I need to look into >>> them about functionalities before fully trust what LLM says. >> Yeah, let me take a look tomorrow. > > I will reply to these patches individually in terms of rebasing on > top of mm-stable and how they interact with Zhang Yi’s changes. > It is not too bad at first look. > >> >> I cannot put into words how much this shmem + pagecache shite annoys me. >> >> What a piece of crap people created here. And looking at the massive changes to >> fix stuff, what a piece of crap people are creating. >> >> I better go to sleep now :) > > Good night. :) Thanks! :) -- Cheers, David