From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753002AbcLEWro (ORCPT ); Mon, 5 Dec 2016 17:47:44 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:60641 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751524AbcLEWrj (ORCPT ); Mon, 5 Dec 2016 17:47:39 -0500 Message-ID: <1480978052.28987.58.camel@infradead.org> Subject: Re: [PATCH] iommu/intel: disable DMAR for Q35 integrated gfx From: David Woodhouse To: Kees Cook Cc: Daniel Vetter , iommu@lists.linux-foundation.org, Jani Nikula , intel-gfx@lists.freedesktop.org, Joerg Roedel , LKML Date: Mon, 05 Dec 2016 22:47:32 +0000 In-Reply-To: References: <20161205215841.GA20819@beast> <1480975635.81411.4.camel@infradead.org> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.18.5.2-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2016-12-05 at 14:18 -0800, Kees Cook wrote: > Hm, I have no idea. :) What would I look for in the BIOS? For a start, what is the actual failure mode? > I figured since g4 was busted, surely q35 was too, since it's even > older... Oh no, they all have different failures. Intel never actually *tested* their graphics hardware before shipping it, but IIRC it was only Q4x where we concluded the hardware was just too broken to live.