diff --git a/drivers/infiniband/hw/mthca/mthca_mr.c b/drivers/infiniband/hw/mthca/mthca_mr.c
index 5eb6e07..6665637 100644
--- a/drivers/infiniband/hw/mthca/mthca_mr.c
+++ b/drivers/infiniband/hw/mthca/mthca_mr.c
@@ -231,7 +231,7 @@
 		mthca_table_put(dev, dev->mr_table.mpt_table, key);
 
 err_out_mpt_free:
-	mthca_free(&dev->mr_table.mpt_alloc, mr->ibmr.lkey);
+	mthca_free(&dev->mr_table.mpt_alloc, key);
 	kfree(mailbox);
 	return err;
 }
@@ -368,7 +368,7 @@
 		mthca_table_put(dev, dev->mr_table.mpt_table, key);
 
 err_out_mpt_free:
-	mthca_free(&dev->mr_table.mpt_alloc, mr->ibmr.lkey);
+	mthca_free(&dev->mr_table.mpt_alloc, key);
 	return err;
 }