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 45719606A33B for ; Wed, 11 Nov 2026 06:16:45 +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=FzULbizw; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=OArMx+t8 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=fscXIP2li/I0NRYzz1oi4vQZQC1ldclu1W8hz2ayPZM=; b=FzULbizwd6ksCGMRWHktxWwJ15 C4Eu2yBKZPjcpDFTATbd2IIFXqIWwfLyinugUS6apBzP3SXxtSMrba1xwuKJZvnLXKOaNR1UaO+h3 0LMK+pXVPkP+QYvQLqdYoeV9yWR8xkPfpbgpd8+lbFqE6qhkftYIdaDLsIM+rpWX4FGF8/6yXziiT 58oBJ7xvgk7hcCisbTpqHpzIED3Fq1tQIUB+Am8jFgtR1sX/WSEsNJXfoG6Tdo1/EbSXeDm8AZpGr 6daFPPvIQLWS8rYu52p6UzXl5a+HfMgy+XV2/KQXBdXkQxS+Ox9PmTMJAmIeD855K7nO18R50lmZH SkfVfLfg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xR1dU-00000005j7x-461q; Wed, 11 Nov 2026 06:16:44 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.100.1 #2 (Red Hat Linux)) id 1xR1dS-00000005j4f-1CJ7 for kexec@lists.infradead.org; Wed, 11 Nov 2026 06:16:42 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id BEFC645AD9; Wed, 11 Nov 2026 06:16:41 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4E3621F00A06; Wed, 11 Nov 2026 06:16:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794377801; bh=fscXIP2li/I0NRYzz1oi4vQZQC1ldclu1W8hz2ayPZM=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=OArMx+t8JccceqnmvhU8sc6QFtIfmaCVldSfP6Y/co0u6nZzbEAwSYMrHdIqGuhiR Ygi7CsqEgyE/v3uqMYgJ7hNlWG0fErD/UHsSU/WEH8JpofK3/5G+mFvMQ4Z+wTi1jL syEORqaGNydjbql0uOpp9w3allnnjaYYeZMnrs5IRVxLT/u8XrHkP0rZL8UVvWDMXT 3j+9eNVtco746JUidsgVUGDFyu4rrVoiO4OxdjPDPKvvnTCCEjIODem5aOS84JFH1u ltbzVdzhbbsskPFTy44U0XzR42rNVCKuliar2uI8IMjzqrxA0TSpZvVSKQ1oNTPqz3 tGmNATGDTbZdA== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v4 08/19] kho: block: Add the feature header to blocks To: "Tarun Sahu" , "Pasha Tatashin" , "Mike Rapoport" , robin.murphy@arm.com, maz@kernel.org, will@kernel.org, "David Matlack" , "Alexander Graf" , seanjc@google.com, jgg@nvidia.com, loganodell@google.com, arnd@arndb.de, dwmw2@infradead.org, baolu.lu@linux.intel.com, "Bjorn Helgaas" , oupton@kernel.org, alex@shazbot.org, gle.com@google.com, pbonzini@redhat.com, "Andrew Morton" , kevin.tian@intel.com, joro@8bytes.org Cc: linux-pci@vger.kernel.org, "Pratyush Yadav" , kexec@lists.infradead.org, skhawaja@google.com, sagis@google.com In-Reply-To: <20261110050202.529473-9-tarunsahu@google.com> References: <20261110050202.529473-1-tarunsahu@google.com> <20261110050202.529473-9-tarunsahu@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 11 Nov 2026 06:16:39 +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: > Subsystems using the KHO Serialization Blocks framework currently rely > on whole-structure compatibility strings to validate serialized block > sets across kexec. Any modification to the block structure layout > constitutes a breaking change and breaks compatibility between adjacent > kernels. >=20 > Precede struct kho_block_header_ser with struct kho_ser_hdr using > DECLARE_KHO_SER. Each block in a block set starts with struct > kho_ser_hdr followed by struct kho_block_header_ser. Serialized entries > start immediately after the header payload at offset fhdr->size. > Block capacity is computed as (KHO_BLOCK_SIZE - fhdr->size) / > bs->entry_size. Subsystems can append future block-level metadata under > new feature indices without altering existing offsets. >=20 > On restore, the location of the first entry and the block capacity no > longer depend on the caller. They are derived from the header size and > entry size the source kernel serialized with, even if the target kernel > structures have a different size. Fields that the source kernel did not > serialize are absent: a subsystem must not access them unless the > corresponding feature is present in the incoming header, as doing so > reads memory outside the serialized data. >=20 > During restoration, blocks whose header does not fit the block are > rejected, and the chain walk stops at such a block. Validate each block > header and reject unknown required features. >=20 > Signed-off-by: Tarun Sahu Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110050202.5294= 73-1-tarunsahu@google.com?part=3D8