diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c
index 7abe9e85a570..9aae6eb604b1 100644
--- a/drivers/iommu/mtk_iommu.c
+++ b/drivers/iommu/mtk_iommu.c
@@ -1264,7 +1264,7 @@ static int mtk_iommu_probe(struct platform_device *pdev)
 	data->plat_data = of_device_get_match_data(dev);
 
 	/* Protect memory. HW will access here while translation fault.*/
-	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2, GFP_KERNEL);
+	protect = devm_kcalloc(dev, 2, MTK_PROTECT_PA_ALIGN, GFP_KERNEL);
 	if (!protect)
 		return -ENOMEM;
 	data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);
diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c
index 25b41222abae..45cd845d153f 100644
--- a/drivers/iommu/mtk_iommu_v1.c
+++ b/drivers/iommu/mtk_iommu_v1.c
@@ -621,8 +621,8 @@ static int mtk_iommu_v1_probe(struct platform_device *pdev)
 	data->dev = dev;
 
 	/* Protect memory. HW will access here while translation fault.*/
-	protect = devm_kzalloc(dev, MTK_PROTECT_PA_ALIGN * 2,
-			GFP_KERNEL | GFP_DMA);
+	protect = devm_kcalloc(dev, 2, MTK_PROTECT_PA_ALIGN,
+			       GFP_KERNEL | GFP_DMA);
 	if (!protect)
 		return -ENOMEM;
 	data->protect_base = ALIGN(virt_to_phys(protect), MTK_PROTECT_PA_ALIGN);