From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matthew Garrett Subject: Re: [PATCH 3/4] driver: provide sysfs interfaces to access TXT log Date: Thu, 9 May 2013 12:02:18 +0000 Message-ID: <1368100938.2425.36.camel@x230> References: <1367938519-840-1-git-send-email-qiaowei.ren@intel.com> <1367938519-840-4-git-send-email-qiaowei.ren@intel.com> <1367990202.2425.26.camel@x230> <9E0BE1322F2F2246BD820DA9FC397ADE9A9BD2@SHSMSX102.ccr.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from tx2ehsobe004.messaging.microsoft.com ([65.55.88.14]:27269 "EHLO tx2outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751260Ab3EIMCX (ORCPT ); Thu, 9 May 2013 08:02:23 -0400 In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE9A9BD2@SHSMSX102.ccr.corp.intel.com> Content-Language: en-US Content-ID: <6D4AA352115FF9489380276ACF93B1C4@namprd05.prod.outlook.com> Sender: platform-driver-x86-owner@vger.kernel.org List-ID: To: "Ren, Qiaowei" Cc: "linux-kernel@vger.kernel.org" , "platform-driver-x86@vger.kernel.org" , "Wei, Gang" T24gVGh1LCAyMDEzLTA1LTA5IGF0IDA4OjA1ICswMDAwLCBSZW4sIFFpYW93ZWkgd3JvdGU6DQo+ IE9uIDIwMTMtMDUtMDgsIE1hdHRoZXcgR2FycmV0dCB3cm90ZToNCj4gPiBIb3cgZGlmZmVyZW50 IGFyZSB0aGVzZSBsb2dzIHRvIHRoZSBUUE0gbWVhc3VyZW1lbnRzIGV4cG9ydGVkIHZpYQ0KPiA+ IHNlY3VyaXR5ZnM/DQo+IA0KPiBUaGVzZSBsb2dzIGNvbWUgZnJvbSB0Ym9vdCAoVHJ1c3RlZCBC b290LCBhbiBvcGVuIHNvdXJjZSwgcHJlLWtlcm5lbC9WTU0gbW9kdWxlIHRoYXQgdXNlcyBJbnRl bMKuIFRydXN0ZWQgRXhlY3V0aW9uIFRlY2hub2xvZ3kgKEludGVswq4gVFhUKSB0byBwZXJmb3Jt IGEgbWVhc3VyZWQgYW5kIHZlcmlmaWVkIGxhdW5jaCBvZiBhbiBPUyBrZXJuZWwvVk1NLiksIGFu ZCBzaG91bGQgYmUgZGlmZmVyZW50IGZyb20gdGhvc2UgVFBNIG1lYXN1cmVtZW50cyAoZnJvbSBC SU9TPykgZXhwb3J0ZWQgdmlhIHNlY3VyaXR5Lg0KDQpEaWZmZXJlbnQgaW4gd2hhdCB3YXk/IFdo YXQgYXJlIHRoZXkgYWN0dWFsbHkgbG9nZ2luZz8NCg0KPiA+IFNvIEkgd3JpdGUgYSB2YWx1ZSBo ZXJlIGFuZCB0aGVuIEkgc2VlIGRpZmZlcmVudCBjaHVua3Mgb2YgbG9nPyBUaGlzDQo+ID4gZG9l c24ndCBzZWVtIGxpa2UgYW4gb3B0aW1hbCBpbnRlcmZhY2UuIFdoYXQgZG8gdGhlc2UgbG9ncyBh Y3R1YWxseQ0KPiA+IGNvbnRhaW4/IEhvdyBkbyBJIGtub3cgd2hpY2ggYmxvY2sgSSBzaG91bGQg YmUgcmVhZGluZz8NCj4gDQo+IFllcy4gU2luY2UgdG90YWwgbG9nIHNpemUgaXMgYmlnZ2VyIHRo YW4gb25lIHBhZ2UgNEssIHRoZSBsb2cgaGF2ZSB0byBiZSBkaXNwbGF5ZWQgaW4gNEstYmxvY2sg aW5kZXhlZCBieSBibG9ja19pbmRleC4NCj4gVGhlc2UgbG9ncyB3aWxsIGJlIHZlcnkgaGVscGZ1 bCBmb3IgdHh0IHJlbGF0ZWQgZGVidWdnaW5nLg0KDQpJZiB0aGV5J3JlIG9ubHkgaW50ZW5kZWQg Zm9yIGRlYnVnZ2luZyB0aGVuIHN5c2ZzIHByb2JhYmx5IGlzbid0IHRoZQ0KYmVzdCBwbGFjZSBm b3IgdGhlbS4gZGVidWdmcyBtaWdodCBtYWtlIG1vcmUgc2Vuc2UuDQoNCi0tIA0KTWF0dGhldyBH YXJyZXR0IHwgbWpnNTlAc3JjZi51Y2FtLm9yZw0K From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754846Ab3EIMCZ (ORCPT ); Thu, 9 May 2013 08:02:25 -0400 Received: from tx2ehsobe004.messaging.microsoft.com ([65.55.88.14]:27269 "EHLO tx2outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751260Ab3EIMCX (ORCPT ); Thu, 9 May 2013 08:02:23 -0400 X-Forefront-Antispam-Report: CIP:157.56.236.101;KIP:(null);UIP:(null);IPV:NLI;H:BY2PRD0510HT005.namprd05.prod.outlook.com;RD:none;EFVD:NLI X-SpamScore: -3 X-BigFish: PS-3(zz98dIc89bh936eI1432Izz1f42h1ee6h1de0h1fdah1202h1e76h1d1ah1d2ah1fc6hzz8275dhz2fh2a8h668h839h93fhd24hd2bhf0ah1288h12a5h12a9h12bdh137ah13b6h1441h1504h1537h153bh162dh1631h1758h18e1h1946h19b5h1ad9h1b0ah1d0ch1d2eh1d3fh1155h) From: Matthew Garrett To: "Ren, Qiaowei" CC: "linux-kernel@vger.kernel.org" , "platform-driver-x86@vger.kernel.org" , "Wei, Gang" Subject: Re: [PATCH 3/4] driver: provide sysfs interfaces to access TXT log Thread-Topic: [PATCH 3/4] driver: provide sysfs interfaces to access TXT log Thread-Index: AQHOSvE9bxnf/3s/7UWUo8Zw/n8iKpj6wJAAgAG87bCAAEa7AA== Date: Thu, 9 May 2013 12:02:18 +0000 Message-ID: <1368100938.2425.36.camel@x230> References: <1367938519-840-1-git-send-email-qiaowei.ren@intel.com> <1367938519-840-4-git-send-email-qiaowei.ren@intel.com> <1367990202.2425.26.camel@x230> <9E0BE1322F2F2246BD820DA9FC397ADE9A9BD2@SHSMSX102.ccr.corp.intel.com> In-Reply-To: <9E0BE1322F2F2246BD820DA9FC397ADE9A9BD2@SHSMSX102.ccr.corp.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.255.84.4] Content-Type: text/plain; charset="utf-8" Content-ID: <6D4AA352115FF9489380276ACF93B1C4@namprd05.prod.outlook.com> MIME-Version: 1.0 X-OriginatorOrg: nebula.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id r49C2URs014985 On Thu, 2013-05-09 at 08:05 +0000, Ren, Qiaowei wrote: > On 2013-05-08, Matthew Garrett wrote: > > How different are these logs to the TPM measurements exported via > > securityfs? > > These logs come from tboot (Trusted Boot, an open source, pre-kernel/VMM module that uses Intel® Trusted Execution Technology (Intel® TXT) to perform a measured and verified launch of an OS kernel/VMM.), and should be different from those TPM measurements (from BIOS?) exported via security. Different in what way? What are they actually logging? > > So I write a value here and then I see different chunks of log? This > > doesn't seem like an optimal interface. What do these logs actually > > contain? How do I know which block I should be reading? > > Yes. Since total log size is bigger than one page 4K, the log have to be displayed in 4K-block indexed by block_index. > These logs will be very helpful for txt related debugging. If they're only intended for debugging then sysfs probably isn't the best place for them. debugfs might make more sense. -- Matthew Garrett | mjg59@srcf.ucam.org {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I