Hi Mike,

[FYI, it's a private test report for your RFC patch.]
[auto build test WARNING on linus/master]
[also build test WARNING on v5.12-rc3 next-20210319]
[cannot apply to linux/master]
[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]

url:    https://github.com/0day-ci/linux/commits/Mike-Kravetz/hugetlb-add-demote-split-page-functionality/20210309-081944
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 144c79ef33536b4ecb4951e07dbc1f2b7fa99d32
config: i386-randconfig-r005-20210318 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://github.com/0day-ci/linux/commit/c49b5026f94b3358774d991cd0b2c2f5720c07a7
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Mike-Kravetz/hugetlb-add-demote-split-page-functionality/20210309-081944
        git checkout c49b5026f94b3358774d991cd0b2c2f5720c07a7
        # save the attached .config to linux build tree
        make W=1 ARCH=i386 

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

All warnings (new ones prefixed by >>):

   mm/hugetlb.c: In function 'demote_size_show':
>> mm/hugetlb.c:3011:16: warning: variable 'demote_size' set but not used [-Wunused-but-set-variable]
    3011 |  unsigned long demote_size;
         |                ^~~~~~~~~~~


vim +/demote_size +3011 mm/hugetlb.c

  3006	
  3007	static ssize_t demote_size_show(struct kobject *kobj,
  3008						struct kobj_attribute *attr, char *buf)
  3009	{
  3010		struct hstate *h;
> 3011		unsigned long demote_size;
  3012		int nid;
  3013	
  3014		h = kobj_to_hstate(kobj, &nid);
  3015		demote_size = h->demote_order;
  3016	
  3017		return sysfs_emit(buf, "%lukB\n",
  3018				(unsigned long)(PAGE_SIZE << h->demote_order) / SZ_1K);
  3019	}
  3020	HSTATE_ATTR_RO(demote_size);
  3021	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all(a)lists.01.org