diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 2297ec1..cb9e114 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -589,7 +589,9 @@
 {
 	int i;
 
-	domain->iommu_coherency = 1;
+	i = find_first_bit(domain->iommu_bmp, g_num_of_iommus);
+
+	domain->iommu_coherency = i < g_num_of_iommus ? 1 : 0;
 
 	for_each_set_bit(i, domain->iommu_bmp, g_num_of_iommus) {
 		if (!ecap_coherent(g_iommus[i]->ecap)) {