diff --git a/kernel/cgroup/rdma.c b/kernel/cgroup/rdma.c
index 9967fb25c563..4fdab4cf49e0 100644
--- a/kernel/cgroup/rdma.c
+++ b/kernel/cgroup/rdma.c
@@ -283,7 +283,7 @@ int rdmacg_try_charge(struct rdma_cgroup **rdmacg,
 			ret = PTR_ERR(rpool);
 			goto err;
 		} else {
-			new = rpool->resources[index].usage + 1;
+			new = (s64)rpool->resources[index].usage + 1;
 			if (new > rpool->resources[index].max) {
 				ret = -EAGAIN;
 				goto err;