openwrt 安装 kmod-usb-storage 时，出现错误，无法安装

[0range]

路由器
Lenovo Y1 （ newifi mini ）

系统
openwrt-15.05-ramips-mt7620-Lenovo-y1-squashfs

内核版本
Linux OpenWrt 3.18.20 #1 Fri Sep 4 18:55:05 CEST 2015 mips GNU/Linux

安装 kmod-usb-storage 时遇到的问题为：
root@OpenWrt:~# opkg install kmod-usb-storage
Installing kmod-usb-storage (3.18.14-1) to root...
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/base/kmod-usb-storage_3.18.14-1_ramips_24kec.ipk.
Multiple packages (kmod-usb-core and kmod-usb-core) providing same name marked HOLD or PREFER. Using latest.
Collected errors:
* satisfy_dependencies_for: Cannot satisfy the following dependencies for kmod-usb-storage:
* kernel (= 3.18.14-1-92b80a3320a397d3cfdc1cf53f35c1d8) * kernel (= 3.18.14-1-92b80a3320a397d3cfdc1cf53f35c1d8) *
* opkg_install_cmd: Cannot install package kmod-usb-storage.

搜寻到很多解决方案，都说下载最新固件，升级之后就好了，可是我用的就是最新的固件。