From nobody Tue Dec 16 12:18:43 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 450C6C4167B for ; Thu, 30 Nov 2023 01:33:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344020AbjK3BdD (ORCPT ); Wed, 29 Nov 2023 20:33:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60460 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbjK3BdA (ORCPT ); Wed, 29 Nov 2023 20:33:00 -0500 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 49D8810C9; Wed, 29 Nov 2023 17:33:07 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1701307987; x=1732843987; h=from:date:subject:mime-version:content-transfer-encoding: message-id:references:in-reply-to:to:cc; bh=biVFyY2ZTRVvjAGgkWkvryJWLterO+Gec8l2ksefpWo=; b=ljP6y29ZjVVjuSSKA9MqbfXcK5nxCI+PUk26ZDpIBb/Gt/vKPE3hz0N2 Fx12GonHAhjyoKEgo/PaJM901quIRsGRXNsZAkD6+lM/6/5IMqMYyjQ0U +0cwjQj7egt9Tj2ZmnKf9pdzZlql73lhudowySkxGLX4VWbB5YErp3BwA 9u2sVnvhimUaf+7ZDnbIZHazaIhoGlDzjPvRFbn71Z2X5GDUhc7WHT+/3 Y9pNYF2hoxvrC7YxTpPcYTJDPDxoXr8/uK4rpaJRJ4wsFiQptjCsIU6WD v6huLyRUWW1XmhWDYDXjK+xw/c/0o93qrkKQThfRn4F99floihpran9sE w==; X-IronPort-AV: E=McAfee;i="6600,9927,10909"; a="131554" X-IronPort-AV: E=Sophos;i="6.04,237,1695711600"; d="scan'208";a="131554" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Nov 2023 17:33:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10909"; a="1016467458" X-IronPort-AV: E=Sophos;i="6.04,237,1695711600"; d="scan'208";a="1016467458" Received: from iweiny-mobl.amr.corp.intel.com (HELO localhost) ([10.213.173.40]) by fmsmga006-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Nov 2023 17:33:05 -0800 From: Ira Weiny Date: Wed, 29 Nov 2023 17:33:04 -0800 Subject: [PATCH v2 2/2] cxl/cdat: Fix header sum value in CDAT checksum MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20231117-fix-cdat-cs-v2-2-715399976d4d@intel.com> References: <20231117-fix-cdat-cs-v2-0-715399976d4d@intel.com> In-Reply-To: <20231117-fix-cdat-cs-v2-0-715399976d4d@intel.com> To: Jonathan Cameron , Fan Ni Cc: Dave Jiang , linux-cxl@vger.kernel.org, linux-kernel@vger.kernel.org, Ira Weiny , Huai-Cheng Kuo X-Mailer: b4 0.13-dev-c6835 X-Developer-Signature: v=1; a=ed25519-sha256; t=1701307983; l=1857; i=ira.weiny@intel.com; s=20221211; h=from:subject:message-id; bh=biVFyY2ZTRVvjAGgkWkvryJWLterO+Gec8l2ksefpWo=; b=/VUqKgmQlOysVLm7W9CszCTDQGTWnKoKE2hLzoFNsDwL6Ui9sFi8wmrQKCuaP/Zzmgw28CCvv X5foAbf+1CgD9LRkoGboAgxq43glhLTWP9LZBr0bI6cd6qxPS+2TPcd X-Developer-Key: i=ira.weiny@intel.com; a=ed25519; pk=noldbkG+Wp1qXRrrkfY1QJpDf7QsOEthbOT7vm0PqsE= Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The addition of the DCD support for CXL type-3 devices extended the CDAT table large enough that the checksum being returned was incorrect.[1] This was because the checksum value was using the header length field rather than each of the 4 bytes of the length field. This was previously not seen because the length of the CDAT data was less than 256 thus resulting in an equivalent checksum value. Properly calculate the checksum for the CDAT header. [1] https://lore.kernel.org/all/20231116-fix-cdat-devm-free-v1-1-b148b40707= d7@intel.com/ Fixes: aba578bdace5 ("hw/cxl/cdat: CXL CDAT Data Object Exchange implementa= tion") Cc: Huai-Cheng Kuo Signed-off-by: Ira Weiny Reviewed-by: Dave Jiang Reviewed-by: Fan Ni --- Changes from V1: [djiang: Remove do {} while (0);] --- hw/cxl/cxl-cdat.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/hw/cxl/cxl-cdat.c b/hw/cxl/cxl-cdat.c index 24829cf2428d..67e44a4f992a 100644 --- a/hw/cxl/cxl-cdat.c +++ b/hw/cxl/cxl-cdat.c @@ -49,6 +49,7 @@ static void ct3_build_cdat(CDATObject *cdat, Error **errp) g_autofree CDATTableHeader *cdat_header =3D NULL; g_autofree CDATEntry *cdat_st =3D NULL; uint8_t sum =3D 0; + uint8_t *buf; int ent, i; =20 /* Use default table if fopen =3D=3D NULL */ @@ -95,8 +96,12 @@ static void ct3_build_cdat(CDATObject *cdat, Error **err= p) /* For now, no runtime updates */ cdat_header->sequence =3D 0; cdat_header->length +=3D sizeof(CDATTableHeader); - sum +=3D cdat_header->revision + cdat_header->sequence + - cdat_header->length; + + buf =3D (uint8_t *)cdat_header; + for (i =3D 0; i < sizeof(*cdat_header); i++) { + sum +=3D buf[i]; + } + /* Sum of all bytes including checksum must be 0 */ cdat_header->checksum =3D ~sum + 1; =20 --=20 2.42.0