From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936252AbZLQEHW (ORCPT ); Wed, 16 Dec 2009 23:07:22 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S936233AbZLQEGA (ORCPT ); Wed, 16 Dec 2009 23:06:00 -0500 Received: from kroah.org ([198.145.64.141]:52305 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936217AbZLQEF6 (ORCPT ); Wed, 16 Dec 2009 23:05:58 -0500 X-Mailbox-Line: From gregkh@mini.kroah.org Wed Dec 16 19:57:02 2009 Message-Id: <20091217035702.052247918@mini.kroah.org> User-Agent: quilt/0.48-1 Date: Wed, 16 Dec 2009 19:57:24 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, David Woodhouse Subject: [147/151] intel-iommu: Fix oops with intel_iommu=igfx_off In-Reply-To: <20091217040208.GA26571@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: David Woodhouse commit 44cd613c0e4cd93079ea2a93aa06649d8ca0830a upstream. The hotplug notifier will call find_domain() to see if the device in question has been assigned an IOMMU domain. However, this should never be called for devices with a "dummy" domain, such as graphics devices when intel_iommu=igfx_off is set and the corresponding IOMMU isn't even initialised. If you do that, it'll oops as it dereferences the (-1) pointer. The notifier function should check iommu_no_mapping() for the device before doing anything else. Signed-off-by: David Woodhouse Signed-off-by: Greg Kroah-Hartman --- drivers/pci/intel-iommu.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -3238,6 +3238,9 @@ static int device_notifier(struct notifi struct pci_dev *pdev = to_pci_dev(dev); struct dmar_domain *domain; + if (iommu_no_mapping(dev)) + return 0; + domain = find_domain(pdev); if (!domain) return 0;