From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joerg Roede Subject: [PATCH 2/2] iommu/vt-d: Make sure RMRRs are mapped before domain goes public Date: Mon, 5 Sep 2016 13:02:30 +0200 Message-ID: <1473073350-13591-2-git-send-email-joro@8bytes.org> References: <1473073350-13591-1-git-send-email-joro@8bytes.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1473073350-13591-1-git-send-email-joro-zLv9SwRftAIdnm+yROfE0A@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: David Woodhouse , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: Joerg Roedel , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: iommu@lists.linux-foundation.org From: Joerg Roedel When a domain is allocated through the get_valid_domain_for_dev path, it will be context-mapped before the RMRR regions are mapped in the page-table. This opens a short time window where device-accesses to these regions fail and causing DMAR faults. Fix this by mapping the RMRR regions before the domain is context-mapped. Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu.c | 27 ++++++++++++++++++++------- 1 file changed, 20 insertions(+), 7 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index bcdbe9d..a4407ea 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3428,17 +3428,18 @@ static unsigned long intel_alloc_iova(struct device *dev, static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev) { + struct dmar_domain *domain, *tmp; struct dmar_rmrr_unit *rmrr; - struct dmar_domain *domain; struct device *i_dev; int i, ret; - domain = get_domain_for_dev(dev, DEFAULT_DOMAIN_ADDRESS_WIDTH); - if (!domain) { - pr_err("Allocating domain for %s failed\n", - dev_name(dev)); - return NULL; - } + domain = find_domain(dev); + if (domain) + goto out; + + domain = find_or_alloc_domain(dev, DEFAULT_DOMAIN_ADDRESS_WIDTH); + if (!domain) + goto out; /* We have a new domain - setup possible RMRRs for the device */ rcu_read_lock(); @@ -3457,6 +3458,18 @@ static struct dmar_domain *__get_valid_domain_for_dev(struct device *dev) } rcu_read_unlock(); + tmp = set_domain_for_dev(dev, domain); + if (!tmp || domain != tmp) { + domain_exit(domain); + domain = tmp; + } + +out: + + if (!domain) + pr_err("Allocating domain for %s failed\n", dev_name(dev)); + + return domain; } -- 2.6.6