[akpm-mm:mm-unstable 34/207] include/linux/hugetlb.h:1214:16: error: implicit declaration of function 'linear_page_index'

[kernel test robot <lkp@intel.com>]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
head:   49cb736d092aaa856283e33b78ec3afb3964d82f
commit: cd9119a9480d9d93fdf06792f8f9917cc4f9999c [34/207] mm/userfaultfd: fix hugetlb fault mutex hash calculation
config: nios2-allnoconfig (https://download.01.org/0day-ci/archive/20260307/202603071127.YdvMepoW-lkp@intel.com/config)
compiler: nios2-linux-gcc (GCC) 11.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260307/202603071127.YdvMepoW-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202603071127.YdvMepoW-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from io_uring/rsrc.c:9:
   include/linux/hugetlb.h: In function 'vma_hugecache_offset':
>> include/linux/hugetlb.h:1214:16: error: implicit declaration of function 'linear_page_index' [-Werror=implicit-function-declaration]
    1214 |         return linear_page_index(vma, address);
         |                ^~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors
--
   In file included from mm/show_mem.c:12:
   include/linux/hugetlb.h: In function 'vma_hugecache_offset':
>> include/linux/hugetlb.h:1214:16: error: implicit declaration of function 'linear_page_index' [-Werror=implicit-function-declaration]
    1214 |         return linear_page_index(vma, address);
         |                ^~~~~~~~~~~~~~~~~
   In file included from include/linux/swap.h:13,
                    from mm/show_mem.c:15:
   include/linux/pagemap.h: At top level:
>> include/linux/pagemap.h:1079:23: error: conflicting types for 'linear_page_index'; have 'long unsigned int(const struct vm_area_struct *, const long unsigned int)'
    1079 | static inline pgoff_t linear_page_index(const struct vm_area_struct *vma,
         |                       ^~~~~~~~~~~~~~~~~
   In file included from mm/show_mem.c:12:
   include/linux/hugetlb.h:1214:16: note: previous implicit declaration of 'linear_page_index' with type 'int()'
    1214 |         return linear_page_index(vma, address);
         |                ^~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/linear_page_index +1214 include/linux/hugetlb.h

  1210	
  1211	static inline pgoff_t vma_hugecache_offset(struct hstate *h,
  1212			struct vm_area_struct *vma, unsigned long address)
  1213	{
> 1214		return linear_page_index(vma, address);
  1215	}
  1216	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki