Hi Rocco,

I love your patch! Perhaps something to improve:

[auto build test WARNING on net-next/master]
[also build test WARNING on net/master linus/master sparc-next/master v5.13-rc7 next-20210623]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Rocco-Yue/net-if_arp-add-ARPHRD_PUREIP-type/20210623-195120
base:   https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 38f75922a6905b010f597fc70dbb5db28398728e
config: arm64-allyesconfig (attached as .config)
compiler: aarch64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/ed82e2a7a56fce99884075bbf84bc76195971ddc
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Rocco-Yue/net-if_arp-add-ARPHRD_PUREIP-type/20210623-195120
        git checkout ed82e2a7a56fce99884075bbf84bc76195971ddc
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   drivers/net/ethernet/mediatek/ccmni/ccmni.c: In function 'ccmni_exit':
>> drivers/net/ethernet/mediatek/ccmni/ccmni.c:190:26: warning: variable 'ctlb' set but not used [-Wunused-but-set-variable]
     190 |  struct ccmni_ctl_block *ctlb = NULL;
         |                          ^~~~


vim +/ctlb +190 drivers/net/ethernet/mediatek/ccmni/ccmni.c

   187	
   188	static void __exit ccmni_exit(void)
   189	{
 > 190		struct ccmni_ctl_block *ctlb = NULL;
   191		struct ccmni_inst *ccmni = NULL;
   192		int i;
   193	
   194		ctlb = s_ccmni_ctlb;
   195		if (!s_ccmni_ctlb)
   196			return;
   197		for (i = 0; i < s_ccmni_ctlb->max_num; i++) {
   198			ccmni = s_ccmni_ctlb->ccmni_inst[i];
   199			if (ccmni) {
   200				unregister_netdev(ccmni->dev);
   201				s_ccmni_ctlb->ccmni_inst[i] = NULL;
   202			}
   203		}
   204		kfree(s_ccmni_ctlb);
   205		s_ccmni_ctlb = NULL;
   206	}
   207	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org