diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index 753c7ecf66a80fb0560d1110c72b4f7ec193a6c4..1581565434106027dca83e1e7bae4c640b3febe9 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -572,7 +572,7 @@ int __init detect_intel_iommu(void)
 			x86_init.iommu.iommu_init = intel_iommu_init;
 #endif
 	}
-	early_acpi_os_unmap_memory(dmar_tbl, dmar_tbl_size);
+	early_acpi_os_unmap_memory((void __iomem *)dmar_tbl, dmar_tbl_size);
 	dmar_tbl = NULL;
 
 	return ret ? 1 : -ENODEV;
@@ -1064,7 +1064,7 @@ int dmar_enable_qi(struct intel_iommu *iommu)
 	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO, 0);
 	if (!desc_page) {
 		kfree(qi);
-		iommu->qi = 0;
+		iommu->qi = NULL;
 		return -ENOMEM;
 	}
 
@@ -1074,7 +1074,7 @@ int dmar_enable_qi(struct intel_iommu *iommu)
 	if (!qi->desc_status) {
 		free_page((unsigned long) qi->desc);
 		kfree(qi);
-		iommu->qi = 0;
+		iommu->qi = NULL;
 		return -ENOMEM;
 	}
 
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index dec715c7e525638ba5a8688915ada668aea442a4..948c6a0d0f5a310c98444099741cfa406bf51379 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -382,7 +382,7 @@ struct device_domain_info {
 
 static void flush_unmaps_timeout(unsigned long data);
 
-DEFINE_TIMER(unmap_timer,  flush_unmaps_timeout, 0, 0);
+static DEFINE_TIMER(unmap_timer,  flush_unmaps_timeout, 0, 0);
 
 #define HIGH_WATER_MARK 250
 struct deferred_flush_tables {
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index 3b05d1b939c54a0ec657ec1cbda9329e6e653bc5..228632c99adbae9080f9abea301c1c7335121f48 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -295,8 +295,8 @@ int setup_ioapic_remapped_entry(int irq,
 					     vector, attr);
 }
 
-int set_remapped_irq_affinity(struct irq_data *data, const struct cpumask *mask,
-			      bool force)
+static int set_remapped_irq_affinity(struct irq_data *data,
+				     const struct cpumask *mask, bool force)
 {
 	if (!config_enabled(CONFIG_SMP) || !remap_ops ||
 	    !remap_ops->set_affinity)