Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed, 9 Mar 2022 11:48:23 +0100
From:   Greg KH <gregkh@linuxfoundation.org>
To:     Jonathan McDowell <noodles@fb.com>
Cc:     Dmitrii Okunev <xaionaro@fb.com>,
        Hans de Goede <hdegoede@redhat.com>,
        Mark Gross <markgross@kernel.org>,
        Qiaowei Ren <qiaowei.ren@intel.com>,
        Matthew Garrett <mjg59@srcf.ucam.org>,
        Xiaoyan Zhang <xiaoyan.zhang@intel.com>,
        Pavel Machek <pavel@denx.de>,
        "x86@kernel.org" <x86@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "platform-driver-x86@vger.kernel.org" 
        <platform-driver-x86@vger.kernel.org>
Subject: Re: [RFC PATCH] platform/x86: Add sysfs interface for Intel TXT
 status
Message-ID: <YiiF9wfx3V+K1J33@kroah.com>
References: <1368465884-14779-1-git-send-email-qiaowei.ren@intel.com>
 <1368465884-14779-3-git-send-email-qiaowei.ren@intel.com>
 <20130516160311.GA12299@amd.pavel.ucw.cz>
 <4febd50da7e5007a2797e0f4c969fa5edd0bf725.camel@fb.com>
 <Yg5A4Mupue0V9diu@kroah.com>
 <20220217123753.GA21849@duo.ucw.cz>
 <0cf678e0b01bf421f3db6693a15ac4060501a80a.camel@fb.com>
 <20220222093101.GA23654@amd>
 <YiiD3WM76L3jbMyW@noodles-fedora-PC23Y6EG.dhcp.thefacebook.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YiiD3WM76L3jbMyW@noodles-fedora-PC23Y6EG.dhcp.thefacebook.com>
Precedence: bulk

On Wed, Mar 09, 2022 at 10:40:03AM +0000, Jonathan McDowell wrote:
> (This is an RFC to see if the approach is generally acceptable; unlike
> the previous driver this exposes the information purely as read-only
> status information, so userspace can make an informed decision about the
> system state without having to poke about in /dev/mem. There are still a
> few extra registers I'm trying to dig up information for before a proper
> submission.)
> 
> This module provides read-only access to the Intel TXT (Trusted
> Execution Technology) status registers, allowing userspace to determine
> the status of measured boot and whether the dynamic root of trust for
> measurement (DRTM) has been fully enabled.
> 
> Tools such as txt-stat from tboot
> <https://sourceforge.net/projects/tboot/> can make use of this driver to
> display state rather than relying on access to /dev/mem.
> 
> See Documentation/x86/intel_txt.rst for more information about Intel
> TXT.
> 
> Signed-off-by: Jonathan McDowell <noodles@fb.com>
> ---
>  arch/x86/include/asm/txt.h             |  34 +++++
>  drivers/platform/x86/intel/Kconfig     |  14 ++
>  drivers/platform/x86/intel/Makefile    |   2 +
>  drivers/platform/x86/intel/txt_sysfs.c | 185 +++++++++++++++++++++++++

No Documentation/ABI/ entry for your new sysfs entry?  How can we
evaluate if this is a good api then?

Wait, I don't see any sysfs code in here, are you sure you sent a viable
patch?

confused,

greg k-h