From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752697Ab2KTTnW (ORCPT ); Tue, 20 Nov 2012 14:43:22 -0500 Received: from g6t0187.atlanta.hp.com ([15.193.32.64]:16211 "EHLO g6t0187.atlanta.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752141Ab2KTTnU (ORCPT ); Tue, 20 Nov 2012 14:43:20 -0500 From: Tom Mingarelli To: Alex Williamson , Don Dutile Cc: Linda Knippers , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Shuah Khan , Tom Mingarelli , David Woodhouse , Joerg Roedel Message-Id: <20120917082234.22091.84161.sendpatchset@RHEL63BL460c> Subject: [PATCH v4] intel-iommu: Prevent devices with RMRRs from being placed into SI Domain Date: Tue, 20 Nov 2012 19:43:17 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch is to prevent non-USB devices that have RMRRs associated with them from being placed into the SI Domain during init. This fixes the issue where the RMRR info for devices being placed in and out of the SI Domain gets lost. Signed-off-by: Thomas Mingarelli Tested-by: Shuah Khan --- PATCH v1: https://lkml.org/lkml/2012/6/15/204 PATCH v2: https://lkml.org/lkml/2012/9/18/354 PATCH v3: https://lkml.org/lkml/2012/10/16/375 drivers/iommu/intel-iommu.c | 31 +++++++++++++++++++++++++++++++ 1 files changed, 31 insertions(+), 0 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index d4a4cd4..8c064df 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -2320,8 +2320,39 @@ static int domain_add_dev_info(struct dmar_domain *domain, return 0; } +static bool device_has_rmrr(struct pci_dev *dev) +{ + struct dmar_rmrr_unit *rmrr; + int i; + + for_each_rmrr_units(rmrr) { + for (i = 0; i < rmrr->devices_cnt; i++) { + /* + * Return TRUE if this RMRR contains the device that + * is passed in. + */ + if (rmrr->devices[i] == dev) + return true; + } + } + return false; +} + static int iommu_should_identity_map(struct pci_dev *pdev, int startup) { + + /* + * We want to prevent any device associated with an RMRR from + * getting placed into the SI Domain. This is done because + * problems exist when devices are moved in and out of domains + * and their respective RMRR info is lost. We exempt USB devices + * from this process due to their usage of RMRRs that are known + * to not be needed after BIOS hand-off to OS. + */ + if (device_has_rmrr(pdev) && + (pdev->class >> 8) != PCI_CLASS_SERIAL_USB) + return 0; + if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev)) return 1; -- 1.7.1