arch/x86/include/asm/pgtable_32.h:68:5: warning: "PTRS_PER_PMD" is not defined, evaluates to 0

[kernel test robot]

Hi Masahiro,

FYI, the error/warning still remains.

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   1b907d0507354b74a4f2c286380cd6059af79248
commit: 80b6093b55e31c2c40ff082fb32523d4e852954f kbuild: add -Wundef to KBUILD_CPPFLAGS for W=1 builds
date:   11 months ago
config: i386-allnoconfig (https://download.01.org/0day-ci/archive/20231112/202311121854.UxxoSqkX-lkp@xxxxxxxxx/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231112/202311121854.UxxoSqkX-lkp@xxxxxxxxx/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@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202311121854.UxxoSqkX-lkp@xxxxxxxxx/

All warnings (new ones prefixed by >>):

   In file included from arch/x86/kernel/head_32.S:29:
>> arch/x86/include/asm/pgtable_32.h:68:5: warning: "PTRS_PER_PMD" is not defined, evaluates to 0 [-Wundef]
      68 | #if PTRS_PER_PMD > 1
         |     ^~~~~~~~~~~~


vim +/PTRS_PER_PMD +68 arch/x86/include/asm/pgtable_32.h

^1da177e4c3f41 include/asm-i386/pgtable.h        Linus Torvalds  2005-04-16  58  
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  59  /*
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  60   * This is used to calculate the .brk reservation for initial pagetables.
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  61   * Enough space is reserved to allocate pagetables sufficient to cover all
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  62   * of LOWMEM_PAGES, which is an upper bound on the size of the direct map of
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  63   * lowmem.
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  64   *
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  65   * With PAE paging (PTRS_PER_PMD > 1), we allocate PTRS_PER_PGD == 4 pages for
ea3186b9572a1b arch/x86/include/asm/pgtable_32.h Arvind Sankar   2020-10-29  66   * the PMD's in addition to the pages required for the last level pagetables.
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  67   */
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08 @68  #if PTRS_PER_PMD > 1
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  69  #define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  70  #else
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  71  #define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  72  #endif
1e620f9b23e598 arch/x86/include/asm/pgtable_32.h Boris Ostrovsky 2016-12-08  73  

:::::: The code at line 68 was first introduced by commit
:::::: 1e620f9b23e598ab936ece12233e98e97930b692 x86/boot/32: Convert the 32-bit pgtable setup code from assembly to C

:::::: TO: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
:::::: CC: Ingo Molnar <mingo@xxxxxxxxxx>

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