Re: [linux-next:master 2778/3213] arch/x86/mm/init_64.c:1583:6: error: implicit declaration of function 'vmemmap_use_new_sub_pmd'

On Wed, Mar 10, 2021 at 1:02 PM kernel test robot [off-list ref] wrote:

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   b01d57bfdc41c8f635b08b8a5af8a31217d46936
commit: 3c583493688a0a1276f6a8c0bbc5ece84e77f086 [2778/3213] x86/vmemmap: handle unpopulated sub-pmd ranges
config: x86_64-randconfig-s022-20210309 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.3-262-g5e674421-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=3c583493688a0a1276f6a8c0bbc5ece84e77f086
        git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
        git fetch --no-tags linux-next master
        git checkout 3c583493688a0a1276f6a8c0bbc5ece84e77f086
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All errors (new ones prefixed by >>):

   arch/x86/mm/init_64.c: In function 'vmemmap_populate_hugepages':

quoted

quoted

arch/x86/mm/init_64.c:1583:6: error: implicit declaration of function 'vmemmap_use_new_sub_pmd' [-Werror=implicit-function-declaration]

    1583 |      vmemmap_use_new_sub_pmd(addr, next);
         |      ^~~~~~~~~~~~~~~~~~~~~~~

quoted

quoted

arch/x86/mm/init_64.c:1589:4: error: implicit declaration of function 'vmemmap_use_sub_pmd' [-Werror=implicit-function-declaration]

    1589 |    vmemmap_use_sub_pmd(addr, next);
         |    ^~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors

But both the functions are defined in arch/x86/mm/init_64.c.

vim +/vmemmap_use_new_sub_pmd +1583 arch/x86/mm/init_64.c

  1530
  1531  static int __meminit vmemmap_populate_hugepages(unsigned long start,
  1532                  unsigned long end, int node, struct vmem_altmap *altmap)
  1533  {
  1534          unsigned long addr;
  1535          unsigned long next;
  1536          pgd_t *pgd;
  1537          p4d_t *p4d;
  1538          pud_t *pud;
  1539          pmd_t *pmd;
  1540
  1541          for (addr = start; addr < end; addr = next) {
  1542                  next = pmd_addr_end(addr, end);
  1543
  1544                  pgd = vmemmap_pgd_populate(addr, node);
  1545                  if (!pgd)
  1546                          return -ENOMEM;
  1547
  1548                  p4d = vmemmap_p4d_populate(pgd, addr, node);
  1549                  if (!p4d)
  1550                          return -ENOMEM;
  1551
  1552                  pud = vmemmap_pud_populate(p4d, addr, node);
  1553                  if (!pud)
  1554                          return -ENOMEM;
  1555
  1556                  pmd = pmd_offset(pud, addr);
  1557                  if (pmd_none(*pmd)) {
  1558                          void *p;
  1559
  1560                          p = vmemmap_alloc_block_buf(PMD_SIZE, node, altmap);
  1561                          if (p) {
  1562                                  pte_t entry;
  1563
  1564                                  entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
  1565                                                  PAGE_KERNEL_LARGE);
  1566                                  set_pmd(pmd, __pmd(pte_val(entry)));
  1567
  1568                                  /* check to see if we have contiguous blocks */
  1569                                  if (p_end != p || node_start != node) {
  1570                                          if (p_start)
  1571                                                  pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
  1572                                                         addr_start, addr_end-1, p_start, p_end-1, node_start);
  1573                                          addr_start = addr;
  1574                                          node_start = node;
  1575                                          p_start = p;
  1576                                  }
  1577
  1578                                  addr_end = addr + PMD_SIZE;
  1579                                  p_end = p + PMD_SIZE;
  1580
  1581                                  if (!IS_ALIGNED(addr, PMD_SIZE) ||
  1582                                      !IS_ALIGNED(next, PMD_SIZE))

quoted

1583                                          vmemmap_use_new_sub_pmd(addr, next);

  1584                                  continue;
  1585                          } else if (altmap)
  1586                                  return -ENOMEM; /* no fallback */
  1587                  } else if (pmd_large(*pmd)) {
  1588                          vmemmap_verify((pte_t *)pmd, node, addr, next);

quoted

1589                          vmemmap_use_sub_pmd(addr, next);

  1590                          continue;
  1591                  }
  1592                  if (vmemmap_populate_basepages(addr, next, node, NULL))
  1593                          return -ENOMEM;
  1594          }
  1595          return 0;
  1596  }
  1597

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