1 files changed, 7 insertions, 5 deletions

diff --git a/arch/x86/kernel/pci-calgary_64.c b/arch/x86/kernel/pci-calgary_64.c
index 849a0995d970..c563e4c8ff39 100644
--- a/arch/x86/kernel/pci-calgary_64.c
+++ b/arch/x86/kernel/pci-calgary_64.c
@@ -316,13 +316,15 @@ static inline struct iommu_table *find_iommu_table(struct device *dev)
 
         pdev = to_pci_dev(dev);
 
+        /* search up the device tree for an iommu */
         pbus = pdev->bus;
-
-        /* is the device behind a bridge? Look for the root bus */
-        while (pbus->parent)
+        do {
+                tbl = pci_iommu(pbus);
+                if (tbl && tbl->it_busno == pbus->number)
+                        break;
+                tbl = NULL;
                 pbus = pbus->parent;
-
-        tbl = pci_iommu(pbus);
+        } while (pbus);
 
         BUG_ON(tbl && (tbl->it_busno != pbus->number));