diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index cfe410eedaf0..323dac9900ba 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -4602,13 +4602,13 @@ static void free_all_cpu_cached_iovas(unsigned int cpu)
 	for (i = 0; i < g_num_of_iommus; i++) {
 		struct intel_iommu *iommu = g_iommus[i];
 		struct dmar_domain *domain;
-		u16 did;
+		int did;
 
 		if (!iommu)
 			continue;
 
 		for (did = 0; did < cap_ndoms(iommu->cap); did++) {
-			domain = get_iommu_domain(iommu, did);
+			domain = get_iommu_domain(iommu, (u16)did);
 
 			if (!domain)
 				continue;