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 67959606A32D for ; Thu, 12 Nov 2026 00:31:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=v0MD6jMY; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=jV8ZN2V8 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=n2DLkGxJnSbmGCrxwXPwOmko4Nq/oIQoKWE8FxALXB4=; b=v0MD6jMYN8fslsGBgL+/btud4L N0Tha/LHk6L/V0C9Esoj5RZ/FnZDykdCW7cD+RWpkCpxMQD7yJNLooqGIFpsTJW39wJYhFhZy7L2Y ONpRZ/+Zf/JjVM5i4Vef9gcsOYyllrPdsebAelAbzolXGUMKhx8WIRV4LxfhLAX4DJJvszWMavnAw NOUaoZitkgD9vOH5zDSaHedPlMINQBvrZeMM4KdY2GeBThu9WljsyKy+IcRGcTXyV5woN3gDw0NOm +frP2hk/8RApHDRBWv7eFEDOk9ztsJ0wGNrnhnQSBZXf2tc6oGNPeRa1pO8HKFjDuddEI5dlZMwae YIStPmkw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRIis-00000008FNw-05vs; Thu, 12 Nov 2026 00:31:26 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xRIip-00000008FK5-14rc for kexec@lists.infradead.org; Thu, 12 Nov 2026 00:31:23 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 081C5412C7; Thu, 12 Nov 2026 00:31:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F1D131F00A05; Thu, 12 Nov 2026 00:31:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794443482; bh=n2DLkGxJnSbmGCrxwXPwOmko4Nq/oIQoKWE8FxALXB4=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=jV8ZN2V8elC5tg1hqboCWazEECOipHcdQQdNUfBPFa4cl6x4IklnhUCXJUfwjcKB8 txpxzEOVetNzjGEwTptX43XOVN8d27dELPQbJLmZ3BeUtVXD6WcY2MMVkFOvtGXazS 6BYD7gWcvRwsyTeDurYDYsDLDrBWULSEyDkeTyuXOsh4V6bmR3W5JN6lfDwpDoYxzV jKyrNITrJwBKWusdLnClcBLNcVEC1GKXAYE4JLhlOJ7xxEudab3T4u4nS43xXn84dX dizQ8/GDNQwu3LT3KG4/U3ZW+oKmR7oXa0pJGQ5TN0qpn8pa5axDq56kGenxBoT9LT Mq6ZVqiLtPhow== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v4 13/19] mm/shmem_luo: Allow preserving tmpfs files To: "David Matlack" , kexec@lists.infradead.org Cc: "Alexander Graf" , "Andrew Morton" , "Baolin Wang" , "Christian Brauner" , "David Hildenbrand" , "Hugh Dickins" , "Jonathan Corbet" , "Liam R. Howlett" , "Lorenzo Stoakes" , "Michal Hocko" , "Mike Rapoport" , "Pasha Tatashin" , "Pratyush Yadav" , "Randy Dunlap" , "Samiullah Khawaja" , "Shuah Khan" , "Suren Baghdasaryan" , "Vlastimil Babka" In-Reply-To: <20261111002358.1842967-14-dmatlack@google.com> References: <20261111002358.1842967-1-dmatlack@google.com> <20261111002358.1842967-14-dmatlack@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Thu, 12 Nov 2026 00:31:21 +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=-10.9 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: > Allow preserving files on tmpfs mounts by dropping the link count check > from shmem_luo_can_preserve(). The check was meant to limit preservation > to memfds, which never have links. It isn't needed anymore, since tmpfs > files are now retrieved into a file on a tmpfs mount. >=20 > Userspace can keep using a linked file by its path until the Live > Update. The path of the file isn't preserved. Userspace creates the file > to retrieve it into, and can then link that file at the path it wants. >=20 > Preserving a linked file affects everyone who opens it by its path, > since its size is frozen while it is preserved. The permission check > added by "mm/shmem_luo: Require permission to preserve a file" covers > that: Callers need permission to write to the file, or must own it if > its size can't change anyway. >=20 > Signed-off-by: David Matlack Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261111002358.1842= 967-1-dmatlack@google.com?part=3D13