From mboxrd@z Thu Jan 1 00:00:00 1970 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 589CEC4332F for ; Wed, 12 Oct 2022 23:01:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229658AbiJLXBi (ORCPT ); Wed, 12 Oct 2022 19:01:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51660 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229640AbiJLXBh (ORCPT ); Wed, 12 Oct 2022 19:01:37 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A4C4E4A; Wed, 12 Oct 2022 16:01:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1665615696; x=1697151696; h=message-id:date:mime-version:from:subject:to:cc: references:in-reply-to:content-transfer-encoding; bh=TQ4RFyACq3aRPxcEOgfEBDFxfsmGybilFCWDTC8Y6+s=; b=A4TxOIb850nBBeQK2X2xNSWTztiBE0duuxCxpjvla0O91JOogQu9i0Ay jNjA7Pfb4dyLnz8oxEoUjxYaN222yPVB6MkEeQPmwaRA/T+G2xWxIhPji gZk1Dg1CP+uRRCmiEV9HrMpGERcHyxhQym2nxWgV4ODV+DP/dL+XQQH8o ddjdZ/c9D8o9hFaMqaEx2CoogjM3vO/QtV4P1DQv2jMDOkkQLcQrW5gHQ l8qsycbI5fFUPmKRG6fm4jX7tEtOrLRVkYVOxM9JukRNa4CkdjDJHdBEN a1ZGeUM+H6wTbi7li+HAzJsZjtK7l+d5HcC9ffgtrA3jvhF11K8+Dwc4Y w==; X-IronPort-AV: E=McAfee;i="6500,9779,10498"; a="305988543" X-IronPort-AV: E=Sophos;i="5.95,180,1661842800"; d="scan'208";a="305988543" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Oct 2022 16:01:34 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10498"; a="695652822" X-IronPort-AV: E=Sophos;i="5.95,180,1661842800"; d="scan'208";a="695652822" Received: from jbrolli1-mobl.amr.corp.intel.com (HELO [10.212.174.189]) ([10.212.174.189]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Oct 2022 16:01:32 -0700 Message-ID: Date: Wed, 12 Oct 2022 16:01:31 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.11.0 From: Sathyanarayanan Kuppuswamy Subject: Re: [PATCH v14 2/3] virt: Add TDX guest driver To: Borislav Petkov Cc: Thomas Gleixner , Ingo Molnar , Dave Hansen , x86@kernel.org, Shuah Khan , Jonathan Corbet , "H . Peter Anvin" , Greg Kroah-Hartman , "Kirill A . Shutemov" , Tony Luck , Kai Huang , Wander Lairson Costa , Isaku Yamahata , marcelo.cerri@canonical.com, tim.gardner@canonical.com, khalid.elmously@canonical.com, philip.cox@canonical.com, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-doc@vger.kernel.org References: <20220928215535.26527-1-sathyanarayanan.kuppuswamy@linux.intel.com> <20220928215535.26527-3-sathyanarayanan.kuppuswamy@linux.intel.com> Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org On 10/12/22 8:47 AM, Borislav Petkov wrote: > On Wed, Sep 28, 2022 at 02:55:34PM -0700, Kuppuswamy Sathyanarayanan wrote: >> +static long tdx_get_report(void __user *argp) >> +{ >> + u8 *reportdata, *tdreport; >> + struct tdx_report_req req; >> + long ret; >> + >> + if (copy_from_user(&req, argp, sizeof(req))) >> + return -EFAULT; >> + >> + /* >> + * Per TDX Module 1.0 specification, section titled >> + * "TDG.MR.REPORT", REPORTDATA length is fixed as >> + * TDX_REPORTDATA_LEN, TDREPORT length is fixed as >> + * TDX_REPORT_LEN, and TDREPORT subtype is fixed as 0. >> + */ >> + if (req.subtype || req.rpd_len != TDX_REPORTDATA_LEN || >> + req.tdr_len != TDX_REPORT_LEN) >> + return -EINVAL; >> + >> + if (memchr_inv(req.reserved, 0, sizeof(req.reserved))) > > I'm guessing we should issue something here to userspace to let it know > why the it fails getting the report. I am fine with adding an error message here. What about the above -EINVAL case? Do you suggest adding it there as well? > > Otherwise it is starting to look good and boring. :) > > Thx. > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer