Re: [song-md:md-next 9/14] ERROR: modpost: "__udivdi3" undefined!

[Yufen Yu <yuyufen@huawei.com>]

On 2020/7/23 5:31, Song Liu wrote:
> On Wed, Jul 22, 2020 at 2:21 PM kernel test robot <lkp@intel.com> wrote:
>>
>> tree:   git://git.kernel.org/pub/scm/linux/kernel/git/song/md.git md-next
>> head:   fe630de009d0729584d79c78f43121e07c745fdc
>> commit: e236858243d7a8e0ac60972d2f9522146088a736 [9/14] md/raid5: set default stripe_size as 4096
>> config: m68k-sun3_defconfig (attached as .config)
>> compiler: m68k-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
>>          git checkout e236858243d7a8e0ac60972d2f9522146088a736
>>          # save the attached .config to linux build tree
>>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k
>>
>> If you fix the issue, kindly add following tag as appropriate
>> Reported-by: kernel test robot <lkp@intel.com>
>>
>> All errors (new ones prefixed by >>, old ones prefixed by <<):
>>
>>>> ERROR: modpost: "__udivdi3" [drivers/md/raid456.ko] undefined!
> 
> Yufen, could you please look into this one? I guess it is caused by ilog2().
> 

This compiler error is caused by 64bit division on on 32-bit architectures.
I have send the fix patch.

Thanks,
Yufen