1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index f5a662a50acb..2b4162d9ca30 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -491,7 +491,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
         int map_size;
         u32 ver;
         static int iommu_allocated = 0;
-        int agaw;
+        int agaw = 0;
 
         iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
         if (!iommu)
@@ -507,6 +507,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
         iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
         iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
 
+#ifdef CONFIG_DMAR
         agaw = iommu_calculate_agaw(iommu);
         if (agaw < 0) {
                 printk(KERN_ERR
@@ -514,6 +515,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
                         iommu->seq_id);
                 goto error;
         }
+#endif
         iommu->agaw = agaw;
 
         /* the registers might be more than one page */