diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 9660d09..f4ef4a2 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -536,24 +536,38 @@
 						  struct ib_udata *udata)
 {
 	struct mlx5_ib_dev *dev = to_mdev(ibdev);
-	struct mlx5_ib_alloc_ucontext_req req;
+	struct mlx5_ib_alloc_ucontext_req_v2 req;
 	struct mlx5_ib_alloc_ucontext_resp resp;
 	struct mlx5_ib_ucontext *context;
 	struct mlx5_uuar_info *uuari;
 	struct mlx5_uar *uars;
 	int gross_uuars;
 	int num_uars;
+	int ver;
 	int uuarn;
 	int err;
 	int i;
+	int reqlen;
 
 	if (!dev->ib_active)
 		return ERR_PTR(-EAGAIN);
 
-	err = ib_copy_from_udata(&req, udata, sizeof(req));
+	memset(&req, 0, sizeof(req));
+	reqlen = udata->inlen - sizeof(struct ib_uverbs_cmd_hdr);
+	if (reqlen == sizeof(struct mlx5_ib_alloc_ucontext_req))
+		ver = 0;
+	else if (reqlen == sizeof(struct mlx5_ib_alloc_ucontext_req_v2))
+		ver = 2;
+	else
+		return ERR_PTR(-EINVAL);
+
+	err = ib_copy_from_udata(&req, udata, reqlen);
 	if (err)
 		return ERR_PTR(err);
 
+	if (req.flags || req.reserved)
+		return ERR_PTR(-EINVAL);
+
 	if (req.total_num_uuars > MLX5_MAX_UUARS)
 		return ERR_PTR(-ENOMEM);
 
@@ -626,6 +640,7 @@
 	if (err)
 		goto out_uars;
 
+	uuari->ver = ver;
 	uuari->num_low_latency_uuars = req.num_low_latency_uuars;
 	uuari->uars = uars;
 	uuari->num_uars = num_uars;