Re: [PATCH v4 5/6] mm: cma: add cma_alloc_frozen{_compound}()

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

Hi Kefeng,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]

url:    https://github.com/intel-lab-lkp/linux/commits/Kefeng-Wang/mm-debug_vm_pgtable-add-debug_vm_pgtable_free_huge_page/20251216-195027
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20251216114844.2126250-6-wangkefeng.wang%40huawei.com
patch subject: [PATCH v4 5/6] mm: cma: add cma_alloc_frozen{_compound}()
config: s390-randconfig-r053-20251218 (https://download.01.org/0day-ci/archive/20251220/202512202141.mGkUgIRF-lkp@intel.com/config)
compiler: s390-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251220/202512202141.mGkUgIRF-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/202512202141.mGkUgIRF-lkp@intel.com/

All warnings (new ones prefixed by >>):

   mm/hugetlb_cma.c: In function 'hugetlb_cma_alloc_folio':
>> mm/hugetlb_cma.c:44:11: warning: array subscript [0, 0] is outside array bounds of 'struct cma *[1]' [-Warray-bounds]
       page = cma_alloc_frozen_compound(hugetlb_cma[nid], order);
              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for CAN_DEV
   Depends on [n]: NETDEVICES [=n] && CAN [=m]
   Selected by [m]:
   - CAN [=m] && NET [=y]


vim +44 mm/hugetlb_cma.c

    28	
    29	struct folio *hugetlb_cma_alloc_folio(int order, gfp_t gfp_mask,
    30					      int nid, nodemask_t *nodemask)
    31	{
    32		int node;
    33		struct folio *folio;
    34		struct page *page = NULL;
    35	
    36		if (hugetlb_cma[nid])
    37			page = cma_alloc_frozen_compound(hugetlb_cma[nid], order);
    38	
    39		if (!page && !(gfp_mask & __GFP_THISNODE)) {
    40			for_each_node_mask(node, *nodemask) {
    41				if (node == nid || !hugetlb_cma[node])
    42					continue;
    43	
  > 44				page = cma_alloc_frozen_compound(hugetlb_cma[nid], order);
    45				if (page)
    46					break;
    47			}
    48		}
    49	
    50		if (!page)
    51			return NULL;
    52	
    53		set_page_refcounted(page);
    54		folio = page_folio(page);
    55		folio_set_hugetlb_cma(folio);
    56		return folio;
    57	}
    58	

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