diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index f659088..861550a 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -674,7 +674,7 @@
  * If true, the addresses will be flushed on unmap time, not when
  * they are reused
  */
-extern u32 amd_iommu_unmap_flush;
+extern bool amd_iommu_unmap_flush;
 
 /* Smallest max PASID supported by any IOMMU in the system */
 extern u32 amd_iommu_max_pasid;