diff --git a/net/rds/ib_frmr.c b/net/rds/ib_frmr.c
index bd861191157b..8397aa4a17ac 100644
--- a/net/rds/ib_frmr.c
+++ b/net/rds/ib_frmr.c
@@ -204,19 +204,16 @@ static int rds_ib_map_frmr(struct rds_ib_device *rds_ibdev,
 	 */
 	rds_ib_teardown_mr(ibmr);
 
-	ibmr->sg = sg;
-	ibmr->sg_len = sg_len;
-	ibmr->sg_dma_len = 0;
 	frmr->sg_byte_len = 0;
-	WARN_ON(ibmr->sg_dma_len);
-	ibmr->sg_dma_len = ib_dma_map_sg(dev, ibmr->sg, ibmr->sg_len,
+	ibmr->sg_dma_len = ib_dma_map_sg(dev, sg, sg_len,
 					 DMA_BIDIRECTIONAL);
 	if (unlikely(!ibmr->sg_dma_len)) {
 		pr_warn("RDS/IB: %s failed!\n", __func__);
 		return -EBUSY;
 	}
 
-	frmr->sg_byte_len = 0;
+	ibmr->sg = sg;
+	ibmr->sg_len = sg_len;
 	frmr->dma_npages = 0;
 	len = 0;
 
@@ -264,6 +261,8 @@ static int rds_ib_map_frmr(struct rds_ib_device *rds_ibdev,
 	ib_dma_unmap_sg(rds_ibdev->dev, ibmr->sg, ibmr->sg_len,
 			DMA_BIDIRECTIONAL);
 	ibmr->sg_dma_len = 0;
+	ibmr->sg = NULL;
+	ibmr->sg_len = 0;
 	return ret;
 }