From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754975Ab1KWUsS (ORCPT ); Wed, 23 Nov 2011 15:48:18 -0500 Received: from home.keithp.com ([63.227.221.253]:35500 "EHLO keithp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752819Ab1KWUsQ (ORCPT ); Wed, 23 Nov 2011 15:48:16 -0500 From: Keith Packard To: David Woodhouse , Eugeni Dodonov Cc: Daniel Vetter , intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org Subject: Re: [Intel-gfx] [PATCH] iommu: export no_iommu and dmar_disabled symbols In-Reply-To: <1322080560.15493.206.camel@shinybook.infradead.org> References: <1321684889-18691-1-git-send-email-keithp@keithp.com> <1322073734-26840-1-git-send-email-eugeni.dodonov@intel.com> <1322080560.15493.206.camel@shinybook.infradead.org> User-Agent: Notmuch/0.9 (http://notmuchmail.org) Emacs/23.3.1 (i486-pc-linux-gnu) Date: Wed, 23 Nov 2011 12:48:19 -0800 Message-ID: <86aa7mefak.fsf@sumi.keithp.com> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha256; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable On Wed, 23 Nov 2011 20:36:00 +0000, David Woodhouse w= rote: > This is horrid. In the general case, drivers have no business knowing > this. We need to properly identify what is wrong with this hardware, and > put in a quirk for it =E2=80=94 perhaps refusing to enable the IOMMU at a= ll on > the broken chipsets. That'd be fine with me, right now we're disabling RC6 and semaphores -- semaphores aren't all that important, although they do improve performance a bit. RC6 is important, saving a huge amount of power. I'd also be OK with requiring special options to enable DMAR and having that also disable RC6/semaphores, if you'd rather expose that. In either case, we need something that works and avoids hanging machines. =2D-=20 keith.packard@intel.com --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQIVAwUBTs1cEzYtFsjWk68qAQixXhAA1PVbZutToPD6uqqdXsDzmRi+EDsg02ek d3o+yHG+VZ/Wxx66h6fNrFE8LPtj8pQZu0GB3yOGer+PTGOsFk9gPlMOvhjLEjYs o5Lk09mDEzQM4cm4VKBlcu5mAJZGi1mrFOoSfmmoXPo/QtKbiJdq/9x4+4jKa48t Xi+luNlUotseONp549o662NNm/PEQaWcCHoetHDlhSagYg0I0fKsO6rja6+tMwnr QWlT0KBCF+Q8JxemnJqaTg+ah4vy1gEG9A6blUg2VlOEkF5MnwYAOtsZ4uhvZlyO 5nCOFJfYFY0eGgwbSRzRCc40RHdCdQGiuoPOb0V1i6gdt5DGe45M82+Dk+RVbWPk piTJW6ghM2mKF4f5vKnVsIOH+pbI8qZyt5bD8E9sAt0/caUyKOEuA0RX/tMSbKla DSkcp9HYtgA9mDoEEX80ZU3Q4SXv2qoQIJZX5hYAOjvR9pS7OyL5Ems8D3FfG7FR fec+HC6oyjOEFblQYrlhT/WWk7ALXGNezjsv2YIrNjH0umhZtQX6e5ObxwK7Psvv 8yeyNAjG9vwNhWEIgl5BR5l5C7ohLvc07Ps/NNiHZRviBgXA5q3EGq5X8tSGmVXk PETFdV5cCAzq/Cx4vL7Diid9OG8bX12SiiRymM4b5eGCIaRhGxx2F+VeElZyxH9E 0SX2Sw43TQA= =3bpj -----END PGP SIGNATURE----- --=-=-=--