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 X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 47AABC46499 for ; Fri, 5 Jul 2019 10:15:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 241652085A for ; Fri, 5 Jul 2019 10:15:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728448AbfGEKPF (ORCPT ); Fri, 5 Jul 2019 06:15:05 -0400 Received: from mga05.intel.com ([192.55.52.43]:13012 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726005AbfGEKPE (ORCPT ); Fri, 5 Jul 2019 06:15:04 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 05 Jul 2019 03:15:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,454,1557212400"; d="scan'208";a="363561959" Received: from jsakkine-mobl1.tm.intel.com ([10.237.50.189]) by fmsmga006.fm.intel.com with ESMTP; 05 Jul 2019 03:15:01 -0700 Message-ID: Subject: Re: [PATCH] tpm: Document UEFI event log quirks From: Jarkko Sakkinen To: Randy Dunlap , linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-doc@vger.kernel.org Cc: tweek@google.com, matthewgarrett@google.com, Jonathan Corbet Date: Fri, 05 Jul 2019 13:15:01 +0300 In-Reply-To: <6acf78df-b168-14d3-fea4-9a9d2945e77f@infradead.org> References: <20190703161109.22935-1-jarkko.sakkinen@linux.intel.com> <6acf78df-b168-14d3-fea4-9a9d2945e77f@infradead.org> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.1-2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2019-07-03 at 09:45 -0700, Randy Dunlap wrote: > > +This introduces another problem: nothing guarantees that it is not > > +called before the stub gets to run. Thus, it needs to copy the final > > +events table preboot size to the custom configuration table so that > > +kernel offset it later on. > > ? kernel can offset it later on. EFI stub calculates the total size of the events in the final events table at the time. Later on, TPM driver uses this offset to copy only the events that were actually generated after ExitBootServices(): /* * Copy any of the final events log that didn't also end up in the * main log. Events can be logged in both if events are generated * between GetEventLog() and ExitBootServices(). */ memcpy((void *)log->bios_event_log + log_size, final_tbl->events + log_tbl->final_events_preboot_size, efi_tpm_final_log_size); What would be a better way to describe this? /Jarkko