From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] libata: Deal with ATA8-ACS proposed Trusted/Treacherous Computing features Date: Tue, 30 Oct 2007 09:27:39 -0400 Message-ID: <4727314B.1090801@garzik.org> References: <20071012173918.3f6d2760@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:34315 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752249AbXJ3N1l (ORCPT ); Tue, 30 Oct 2007 09:27:41 -0400 In-Reply-To: <20071012173918.3f6d2760@the-village.bc.nu> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Alan Cox Cc: linux-ide@vger.kernel.org Alan Cox wrote: > Historically word 48 in the identify data was used to mean 32bit I/O was > supported for VLB IDE etc. ATA8 reassigns this word to the Trusted > Computing Group, where it is used for TCG features. This means that an > ATA8 TCG drive is going to trigger 32bit I/O on some systems which will > be funny. Perhaps thats why T13 gave them the word. > > Anyway we need to sort this out ready for ATA8 so: > - Reorder the ata.h header a bit so the ata_version function occurs early > in it > - Make dword_io check the ATA version > - Add an ATA8 version checking TCG presence test > > While we are at it the current drafts have a flaw where it may not be > possible to disable TCG features at boot (and opt out of the trusted > model) as TCG intends because it relies on presence of a different > optional feature (DCS). Handle this in software by refusing the TCG > commands if libata.allow_tpm is not set. (We must make it possible as > some environments such as proprietary VDR devices will doubtless want to > use it to lock up content) > > Finally as with CPRM print a warning so that the user knows they may not > be able to full access and use the device. > > Alan > > Signed-off-by: Alan Cox seems fairly reasonable... 2.6.24-rc?