From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752060Ab1HLOJg (ORCPT ); Fri, 12 Aug 2011 10:09:36 -0400 Received: from os.inf.tu-dresden.de ([141.76.48.99]:56188 "EHLO os.inf.tu-dresden.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751107Ab1HLOJf (ORCPT ); Fri, 12 Aug 2011 10:09:35 -0400 Date: Fri, 12 Aug 2011 16:08:46 +0200 From: "Udo A. Steinberg" To: Dave Airlie Cc: Linux Kernel Mailing List , iommu@lists.linux-foundation.org, David Woodhouse Subject: Re: Kernel panic with intel_iommu=on Message-ID: <20110812160846.29fd9149@laptop.anywhere.org> In-Reply-To: References: <20110812145818.00cde392@laptop.anywhere.org> X-Mailer: X-Mailer 5.0 Gold Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/suR/hM2E12YeNs2mIwb.WtW"; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Sig_/suR/hM2E12YeNs2mIwb.WtW Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Fri, 12 Aug 2011 23:51:47 +1000 Dave Airlie (DA) wrote: DA> Does intel_iommu=3Digfx_off work as well? DA>=20 DA> I've been seeing a few of these with Ironlake chipsets, the reason DA> firefox does it is probably because it causes the 3D driver to be DA> used. With intel_iommu=3Digfx_off it works as well. Looks like that keeps IOMMU 1 disabled. So the bug seems to be in the register-based invalidation of mapp= ings in the DMAR engine that remaps igfx. And it must be something that firefox = 5.0 doesn't trigger, whereas 6.0 does. For completeness, here's the relevant dmesg output with intel_iommu=3Digfx_= off. DMAR: Host address width 36 DMAR: DRHD base: 0x000000feb00000 flags: 0x0 IOMMU 0: reg_base_addr feb00000 ver 1:0 cap c9008020a30270 ecap 1000 DMAR: DRHD base: 0x000000feb01000 flags: 0x0 IOMMU 1: reg_base_addr feb01000 ver 1:0 cap c0000020230270 ecap 1000 DMAR: DRHD base: 0x000000feb03000 flags: 0x1 IOMMU 2: reg_base_addr feb03000 ver 1:0 cap c9008020230270 ecap 1000 DMAR: RMRR base: 0x000000000e0000 end: 0x000000000effff DMAR: RMRR base: 0x0000003e600000 end: 0x0000003effffff DMAR: No ATSR found IOMMU 0 0xfeb00000: using Register based invalidation IOMMU 2 0xfeb03000: using Register based invalidation IOMMU: Setting RMRR: IOMMU: Setting identity map for device 0000:00:1d.0 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1d.1 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1d.2 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1d.7 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1a.0 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1a.1 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1a.2 [0xe0000 - 0xeffff] IOMMU: Setting identity map for device 0000:00:1a.7 [0xe0000 - 0xeffff] IOMMU: Prepare 0-16MiB unity mapping for LPC IOMMU: Setting identity map for device 0000:00:1f.0 [0x0 - 0xffffff] PCI-DMA: Intel(R) Virtualization Technology for Directed I/O Cheers, - Udo --Sig_/suR/hM2E12YeNs2mIwb.WtW Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEARECAAYFAk5FM+4ACgkQnhRzXSM7nSkskQCfZdmxqHMJHlV640vB26e7q82b 6OcAnRZ9ibeS+clg8UN/AVa5LMZxZ73L =uxoc -----END PGP SIGNATURE----- --Sig_/suR/hM2E12YeNs2mIwb.WtW--