Hi Shijie,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on linus/master]
[also build test ERROR on v5.7-rc5 next-20200512]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/Shijie-Hu/hugetlbfs-Get-unmapped-area-below-TASK_UNMAPPED_BASE-for-hugetlbfs/20200513-221024
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 24085f70a6e1b0cb647ec92623284641d8270637
config: riscv-allyesconfig (attached as .config)
compiler: riscv64-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day GCC_VERSION=9.3.0 make.cross ARCH=riscv 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kbuild test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

fs/hugetlbfs/inode.c: In function 'hugetlb_get_unmapped_area':
>> fs/hugetlbfs/inode.c:268:31: error: 'arch_get_unmapped_area' undeclared (first use in this function); did you mean 'thp_get_unmapped_area'?
268 |  if (mm->get_unmapped_area == arch_get_unmapped_area)
|                               ^~~~~~~~~~~~~~~~~~~~~~
|                               thp_get_unmapped_area
fs/hugetlbfs/inode.c:268:31: note: each undeclared identifier is reported only once for each function it appears in

vim +268 fs/hugetlbfs/inode.c

   240	
   241	static unsigned long
   242	hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
   243			unsigned long len, unsigned long pgoff, unsigned long flags)
   244	{
   245		struct mm_struct *mm = current->mm;
   246		struct vm_area_struct *vma;
   247		struct hstate *h = hstate_file(file);
   248	
   249		if (len & ~huge_page_mask(h))
   250			return -EINVAL;
   251		if (len > TASK_SIZE)
   252			return -ENOMEM;
   253	
   254		if (flags & MAP_FIXED) {
   255			if (prepare_hugepage_range(file, addr, len))
   256				return -EINVAL;
   257			return addr;
   258		}
   259	
   260		if (addr) {
   261			addr = ALIGN(addr, huge_page_size(h));
   262			vma = find_vma(mm, addr);
   263			if (TASK_SIZE - len >= addr &&
   264			    (!vma || addr + len <= vm_start_gap(vma)))
   265				return addr;
   266		}
   267	
 > 268		if (mm->get_unmapped_area == arch_get_unmapped_area)
   269			return hugetlb_get_unmapped_area_bottomup(file, addr, len,
   270					pgoff, flags);
   271		return hugetlb_get_unmapped_area_topdown(file, addr, len,
   272				pgoff, flags);
   273	}
   274	#endif
   275	

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0-DAY CI Kernel Test Service, Intel Corporation
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