diff --git a/drivers/scsi/pm8001/pm8001_sas.c b/drivers/scsi/pm8001/pm8001_sas.c
index 949198c01ced..ef1687f798cc 100644
--- a/drivers/scsi/pm8001/pm8001_sas.c
+++ b/drivers/scsi/pm8001/pm8001_sas.c
@@ -463,7 +463,7 @@ err_out:
 	dev_printk(KERN_ERR, pm8001_ha->dev, "pm8001 exec failed[%d]!\n", rc);
 	if (!sas_protocol_ata(t->task_proto))
 		if (n_elem)
-			dma_unmap_sg(pm8001_ha->dev, t->scatter, n_elem,
+			dma_unmap_sg(pm8001_ha->dev, t->scatter, t->num_scatter,
 				t->data_dir);
 out_done:
 	spin_unlock_irqrestore(&pm8001_ha->lock, flags);