xprtrdma: Free the pd if ib_query_qp() fails

commit 5ae711a2 upstream.

If ib_query_qp() fails or the memory registration mode isn't
supported, don't leak the PD. An orphaned IB/core resource will
cause IB module removal to hang.

Fixes: bd7ed1d1 ("RPC/RDMA: check selected memory registration ...")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
[bwh: Backported to 3.2:
 - Adjust context
 - There are only 2 goto's to be changed, not 3]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

net/sunrpc/xprtrdma/verbs.c

@@ -485,7 +485,7 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
 	if (rc) {
 		dprintk("RPC:       %s: ib_query_device failed %d\n",
 			__func__, rc);
-		goto out2;
+		goto out3;
 	}
 
 	if (devattr.device_cap_flags & IB_DEVICE_LOCAL_DMA_LKEY) {
@@ -587,7 +587,7 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
 		printk(KERN_ERR "%s: invalid memory registration mode %d\n",
 				__func__, memreg);
 		rc = -EINVAL;
-		goto out2;
+		goto out3;
 	}
 	dprintk("RPC:       %s: memory registration strategy is %d\n",
 		__func__, memreg);
@@ -596,6 +596,10 @@ rpcrdma_ia_open(struct rpcrdma_xprt *xprt, struct sockaddr *addr, int memreg)
 	ia->ri_memreg_strategy = memreg;
 
 	return 0;
+
+out3:
+	ib_dealloc_pd(ia->ri_pd);
+	ia->ri_pd = NULL;
 out2:
 	rdma_destroy_id(ia->ri_id);
 	ia->ri_id = NULL;