1 files changed, 16 insertions, 7 deletions

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 23824fef789c..adb0ba025702 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -980,7 +980,7 @@ static int alloc_new_range(struct dma_ops_domain *dma_dom,
 {
         int index = dma_dom->aperture_size >> APERTURE_RANGE_SHIFT;
         struct amd_iommu *iommu;
-        int i;
+        unsigned long i;
 
 #ifdef CONFIG_IOMMU_STRESS
         populate = false;
@@ -1489,11 +1489,14 @@ static void __detach_device(struct device *dev)
 {
         struct iommu_dev_data *dev_data = get_dev_data(dev);
         struct iommu_dev_data *alias_data;
+        struct protection_domain *domain;
         unsigned long flags;
 
         BUG_ON(!dev_data->domain);
 
-        spin_lock_irqsave(&dev_data->domain->lock, flags);
+        domain = dev_data->domain;
+
+        spin_lock_irqsave(&domain->lock, flags);
 
         if (dev_data->alias != dev) {
                 alias_data = get_dev_data(dev_data->alias);
@@ -1504,13 +1507,15 @@ static void __detach_device(struct device *dev)
         if (atomic_dec_and_test(&dev_data->bind))
                 do_detach(dev);
 
-        spin_unlock_irqrestore(&dev_data->domain->lock, flags);
+        spin_unlock_irqrestore(&domain->lock, flags);
 
         /*
          * If we run in passthrough mode the device must be assigned to the
-         * passthrough domain if it is detached from any other domain
+         * passthrough domain if it is detached from any other domain.
+         * Make sure we can deassign from the pt_domain itself.
          */
-        if (iommu_pass_through && dev_data->domain == NULL)
+        if (iommu_pass_through &&
+            (dev_data->domain == NULL && domain != pt_domain))
                 __attach_device(dev, pt_domain);
 }
 
@@ -2218,6 +2223,12 @@ static struct dma_map_ops amd_iommu_dma_ops = {
 /*
  * The function which clues the AMD IOMMU driver into dma_ops.
  */
+
+void __init amd_iommu_init_api(void)
+{
+        register_iommu(&amd_iommu_ops);
+}
+
 int __init amd_iommu_init_dma_ops(void)
 {
         struct amd_iommu *iommu;
@@ -2253,8 +2264,6 @@ int __init amd_iommu_init_dma_ops(void)
         /* Make the driver finally visible to the drivers */
         dma_ops = &amd_iommu_dma_ops;
 
-        register_iommu(&amd_iommu_ops);
-
         amd_iommu_stats_init();
 
         return 0;