diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 54d96e847f16..e8d4c2dac4da 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1465,7 +1465,7 @@ int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
 			 */
 			s->dma_address = pci_p2pdma_bus_addr_map(
 				p2pdma_state.mem, sg_phys(s));
-			sg_dma_len(s) = sg->length;
+			sg_dma_len(s) = s->length;
 			sg_dma_mark_bus_address(s);
 			continue;
 		default: