tree:   git://git.cmpxchg.org/linux-mmotm.git master
head:   6102e3c755ac0084fdce65f69a7a149fc51a8a86
commit: 5add70cf3a7cae49778479a9a5a85bfc47ebb3bc [137/321] mm: make GUP handle pfn mapping unless FOLL_GET is requested
config: microblaze-mmu_defconfig (attached as .config)
reproduce:
  wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross
  chmod +x ~/bin/make.cross
  git checkout 5add70cf3a7cae49778479a9a5a85bfc47ebb3bc
  # save the attached .config to linux build tree
  make.cross ARCH=microblaze 

All error/warnings (new ones prefixed by >>):

   mm/gup.c: In function 'follow_pfn_pte':
>> mm/gup.c:51:4: error: implicit declaration of function 'update_mmu_cache' [-Werror=implicit-function-declaration]
       update_mmu_cache(vma, address, pte);
       ^
   cc1: some warnings being treated as errors

vim +/update_mmu_cache +51 mm/gup.c

    45			if (flags & FOLL_WRITE)
    46				entry = pte_mkdirty(entry);
    47			entry = pte_mkyoung(entry);
    48	
    49			if (!pte_same(*pte, entry)) {
    50				set_pte_at(vma->vm_mm, address, pte, entry);
  > 51				update_mmu_cache(vma, address, pte);
    52			}
    53		}
    54	

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0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation