Re: [PATCH] mm: gup: remove FOLL_SPLIT

[John Hubbard <jhubbard@nvidia.com>]

On 3/29/21 11:24 PM, kernel test robot wrote:
> Hi Yang,
> 
> Thank you for the patch! Yet something to improve:
> 
> [auto build test ERROR on hnaz-linux-mm/master]
> 
> url:    https://github.com/0day-ci/linux/commits/Yang-Shi/mm-gup-remove-FOLL_SPLIT/20210330-034042
> base:   https://github.com/hnaz/linux-mm master
> config: s390-randconfig-r032-20210330 (attached as .config)
> compiler: s390-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/c8563a636718f98af86a3965d94e25b8f2cf2354
>          git remote add linux-review https://github.com/0day-ci/linux
>          git fetch --no-tags linux-review Yang-Shi/mm-gup-remove-FOLL_SPLIT/20210330-034042
>          git checkout c8563a636718f98af86a3965d94e25b8f2cf2354
>          # save the attached .config to linux build tree
>          COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=s390
> 
> 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 >>):
> 
>     arch/s390/mm/gmap.c: In function 'thp_split_mm':
>>> arch/s390/mm/gmap.c:2498:27: error: 'FOLL_SPLIT' undeclared (first use in this function); did you mean 'FOLL_PIN'?
>      2498 |    follow_page(vma, addr, FOLL_SPLIT);
>           |                           ^~~~~~~~~~
>           |                           FOLL_PIN
>     arch/s390/mm/gmap.c:2498:27: note: each undeclared identifier is reported only once for each function it appears in
> 
> 
> vim +2498 arch/s390/mm/gmap.c

There appears to be an imperfection in this 0day testing system, because (just as the patch
says), commit ba925fa35057a062ac98c3e8138b013ce4ce351c ("s390/gmap: improve THP splitting"),
July 29, 2020, removes the above use of FOLL_SPLIT.

And "git grep", just to be sure, shows it is not there in today's linux.git. So I guess the
https://github.com/0day-ci/linux repo needs a better way to stay in sync?


thanks,
-- 
John Hubbard
NVIDIA