From: Sagi Grimberg <sagi@grimberg.me>
Date: Wed, 11 Oct 2017 15:29:09 +0300
Subject: nvme-rdma: Check that reinit_request got a proper mr
Patch-mainline: v4.15-rc1
Git-commit: 0fc176dfdafc78e66bd74f54e487ca1fc59d01bf
References: FATE#323952, FATE#322506

Warn if req->mr is NULL as it should never happen.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/nvme/host/rdma.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -274,6 +274,9 @@ static int nvme_rdma_reinit_request(void
 	struct nvme_rdma_request *req = blk_mq_rq_to_pdu(rq);
 	int ret = 0;
 
+	if (WARN_ON_ONCE(!req->mr))
+		return 0;
+
 	ib_dereg_mr(req->mr);
 
 	req->mr = ib_alloc_mr(dev->pd, IB_MR_TYPE_MEM_REG,