diff --git a/module/bdev/compress/vbdev_compress_rpc.c b/module/bdev/compress/vbdev_compress_rpc.c
index 5e7877f5a..53966fd8d 100644
--- a/module/bdev/compress/vbdev_compress_rpc.c
+++ b/module/bdev/compress/vbdev_compress_rpc.c
@@ -130,7 +130,7 @@ free_rpc_construct_compress(struct rpc_construct_compress *r)
 static const struct spdk_json_object_decoder rpc_construct_compress_decoders[] = {
 	{"base_bdev_name", offsetof(struct rpc_construct_compress, base_bdev_name), spdk_json_decode_string},
 	{"pm_path", offsetof(struct rpc_construct_compress, pm_path), spdk_json_decode_string},
-	{"lb_size", offsetof(struct rpc_construct_compress, lb_size), spdk_json_decode_uint32},
+	{"lb_size", offsetof(struct rpc_construct_compress, lb_size), spdk_json_decode_uint32, true},
 };
 
 /* Decode the parameters for this RPC method and properly construct the compress