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 E7788606A332 for ; Wed, 11 Nov 2026 06:16:38 +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=sWqOIie5; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lRWyLjuc 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=XpUjgykRN0vFDha3zJ8L+z/s5zYun/eYAgoPua1NoMA=; b=sWqOIie5Cg5n8NPL8mianagjHt UwsdpfI7W2e2aDqkDCj5Zg5fG2ZDStJnlGoIPWVb8a6lIFUqHCW0bFaj6GrfGRPcjwmcaSlt2hMol bbdqb5x6+tV/ZvCIuKcJGimxjzRHPepNYHEKM63c/MTfl6ENo7gHCZ3hK28TtIclBO8CFkTvzelZU 6EWSFsEMj23hKr5XZOmyslWg4mOqLQLeIhlCTW0HlHsdcGeaC9Uoj0V2V47qxBL4Ocf2A1CmF4CFo kfkUBlFrAbG81oSNg6tFPIYhkuVK3oxub4DsPLKLw1+0j9eFC8WQE1P4BiO2LOrbbEGAmbtILM7N+ ronPDQ8w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.100.1 #2 (Red Hat Linux)) id 1xR1dO-00000005j0x-2hyz; Wed, 11 Nov 2026 06:16:38 +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 1xR1dN-00000005izj-11H2 for kexec@lists.infradead.org; Wed, 11 Nov 2026 06:16:37 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 6389F630B6; Wed, 11 Nov 2026 06:16:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D372B1F00A0B; Wed, 11 Nov 2026 06:16:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794377796; bh=XpUjgykRN0vFDha3zJ8L+z/s5zYun/eYAgoPua1NoMA=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=lRWyLjuc4FqV1ZiNtvfr7F6uvGFhyVzqgThcTe1+qsr8fb9XeRBjhQMREF09XUmd9 NO+GYZidhttYb6TPwGnmncqvDO+xfoInFX1T9wXihWIZ+yux5utnpLx/A1FAqjDlyB OGBO4uNIeNIW/tyifSYQzJMCT0CH2tQZ2vr8HObe/BcEELWg9hhmTA/ycvXwiyoTk7 q5eWxl3V4b7EEhUeYCy9ZJ4JOWIzi4T5/MHmr2Oivl7C/TAeecu3zX16Le3yoCubyh 7ga0WzRSvV+/Bl/TZ2f5jeT/23MKETwOH/qFG0U80sLuLpIa3mPULZ7pjtenMWbEPg Vm2dT4qMunoWQ== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH v4 05/19] kho: Add feature header for fine-grained ABI compatibility 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: <20261110050202.529473-6-tarunsahu@google.com> References: <20261110050202.529473-1-tarunsahu@google.com> <20261110050202.529473-6-tarunsahu@google.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 11 Nov 2026 06:16:34 +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: > Serialized structures in KHO and Live Update Orchestrator currently rely > on whole-structure compatibility strings or monolithic version fields to > validate handed-over state across kexec. Any change to a serialized > structure, even an optional additive field, requires bumping the > compatibility string or version number and breaks live update between > adjacent kernels. >=20 > Introduce a generic feature header (struct kho_ser_hdr) for serialized > binary structures in include/linux/kho/abi/feature.h. Each subsystem > groups the fields of its serialized structure under feature indices, > starting with index 0 for base fields. When a subsystem adds a new > capability, it appends new fields to the end of its payload structure > under a new feature index. Retired fields are kept in place so existing > field offsets never shift; if the type or format of a field needs to > change, the existing field and feature are kept intact until retired and > [ ... ] > layout while deserialization helpers follow the incoming header. >=20 > Suggested-by: David Matlack > Suggested-by: Pasha Tatashin > 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=3D5