Re: [PATCH] hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing

[Mike Kravetz]

On 10/22/22 10:45, kernel test robot wrote:
> Hi Mike,
> 
> I love your patch! Yet something to improve:
> 
> [auto build test ERROR on akpm-mm/mm-everything]
> [also build test ERROR on linus/master v6.1-rc1 next-20221021]
> [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#_base_tree_information]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Mike-Kravetz/hugetlb-don-t-delete-vma_lock-in-hugetlb-MADV_DONTNEED-processing/20221022-070934
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
> patch link:    https://lore.kernel.org/r/20221021230722.370587-1-mike.kravetz%40oracle.com
> patch subject: [PATCH] hugetlb: don't delete vma_lock in hugetlb MADV_DONTNEED processing
> config: powerpc-allnoconfig
> compiler: powerpc-linux-gcc (GCC) 12.1.0
> 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/intel-lab-lkp/linux/commit/b52333ec636c58b31a006e7b4a0e6e9f1280ceaa
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Mike-Kravetz/hugetlb-don-t-delete-vma_lock-in-hugetlb-MADV_DONTNEED-processing/20221022-070934
>         git checkout b52333ec636c58b31a006e7b4a0e6e9f1280ceaa
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash arch/powerpc/kernel/
> 
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@xxxxxxxxx>
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from arch/powerpc/kernel/setup-common.c:37:
> >> include/linux/hugetlb.h:431:13: error: 'clear_hugetlb_page_range' defined but not used [-Werror=unused-function]
>      431 | static void clear_hugetlb_page_range(struct vm_area_struct *vma,
>          |             ^~~~~~~~~~~~~~~~~~~~~~~~
>    cc1: all warnings being treated as errors

Wow!  I was unaware that madvise could be removed via a config option.

I will soon send a v2 with changes as follows:

- Use __maybe_unused on the static stub in the !CONFIG_HUGETLB_PAGE case
  in hugetlb.h.
- Wrap clear_hugetlb_page_range in hugetlb.c with #ifdef CONFIG_ADVISE_SYSCALLS
  so that it is not included if !CONFIG_ADVISE_SYSCALLS.
-- 
Mike Kravetz