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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E66A6C7EE22 for ; Tue, 16 May 2023 01:45:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Dxda0G2lbKGvmkBkt2OsFGtVrfwi/pAOjdlYsMJlMgE=; b=Axg/JbXpUOdCaP gBugfPS0koXkd+W9c6ex3cltMeErhOzm08wWYaTFtfriJ3NAOYkZ261JZ2u3tvWIZVolheBB9J4S+ op9FkBazESlZJWx/DwkDVjpie/1cQJIlDzBv2ASJDi8EJ5LI3WOAylG260YXg7o9Q2xC5zKzAh/gl CgxjKwE+EWhTF2P7TvJBLWy1T4PUEsxw7Yob3XOkN+wshoSSEpsgi/J3jvfDer3esAwBlhTIqCMFA rKe9+J3mGrkjQt+S0RLdhbjMmjYjQ2AEf1NgQBFaBLAUs4HAK+aSK9o8rUA5grx25iwicOQ90/AGe xIgwt5jCjnQa/D0cqV1w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pyjlD-0044TM-1k; Tue, 16 May 2023 01:45:55 +0000 Received: from irc.codon.org.uk ([2a00:1098:84:22e::2] helo=cavan.codon.org.uk) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pyjlA-0044SG-0R for kexec@lists.infradead.org; Tue, 16 May 2023 01:45:53 +0000 Received: by cavan.codon.org.uk (Postfix, from userid 1000) id 7F4FC42529; Tue, 16 May 2023 02:45:49 +0100 (BST) Date: Tue, 16 May 2023 02:45:49 +0100 From: Matthew Garrett To: "Daniel P. Smith" Cc: Ross Philipson , linux-kernel@vger.kernel.org, x86@kernel.org, linux-integrity@vger.kernel.org, linux-doc@vger.kernel.org, linux-crypto@vger.kernel.org, iommu@lists.linux-foundation.org, kexec@lists.infradead.org, linux-efi@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, ardb@kernel.org, James.Bottomley@hansenpartnership.com, luto@amacapital.net, nivedita@alum.mit.edu, kanth.ghatraju@oracle.com, trenchboot-devel@googlegroups.com Subject: Re: [PATCH v6 07/14] x86: Secure Launch kernel early boot stub Message-ID: <20230516014549.GB5403@srcf.ucam.org> References: <20230504145023.835096-1-ross.philipson@oracle.com> <20230504145023.835096-8-ross.philipson@oracle.com> <20230512112623.GE14461@srcf.ucam.org> <98decbe9-846a-6d36-aa7a-f906a19fa6cf@oracle.com> <7ff17d2b-7030-fbbd-c495-b43583e3f9e7@apertussolutions.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <7ff17d2b-7030-fbbd-c495-b43583e3f9e7@apertussolutions.com> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230515_184552_328481_5F70BF33 X-CRM114-Status: GOOD ( 20.12 ) X-BeenThere: kexec@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+kexec=archiver.kernel.org@lists.infradead.org On Mon, May 15, 2023 at 09:11:15PM -0400, Daniel P. Smith wrote: > On 5/12/23 12:17, Ross Philipson wrote: > > This is a good point. At this point it is really something we > > overlooked. We will have to revisit this and figure out the best way to > > find the final event log depending on how things booted. > > I believe Ross misunderstood what you were asking for here. There are two > reasons this is not possible or desired. The first reason is that on Intel, > the DRTM log is not initialized by TrenchBoot code in the preamble. It is > only responsible for allocating a buffer and recording the location in the > TXT structures. When the SINIT ACM is executed, it will initialize the log > and record the measurement that CPU sent directly to the TPM and then the > measurements the ACM makes of the environment. If you pointed at the SRTM > log, then the ACM would write over existing log, which I don't think you > want. Now if you pointed at the tail end of the SRTM log, you would still > end up with a second, separate log that just happens to be memory adjacent. Ok. I think it would be clearer if either the function names or some comments expressly indicated that this refers to the DRTM event log and that that's a separate entity from the SRTM one, "event log" on its own is likely to cause people to think of the existing log rather than associate it with something else. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec