[PATCH v1 1/1] x86/mm: Check if PTRS_PER_PMD is defined before use

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

Compiler is not happy about PTRS_PER_PMD being undefined

In file included from arch/x86/kernel/head_32.S:29:
arch/x86/include/asm/pgtable_32.h:59:5: error: "PTRS_PER_PMD" is not defined, evaluates to 0 [-Werror=undef]
   59 | #if PTRS_PER_PMD > 1

Add a check to make sure PTRS_PER_PMD is defined before use.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/r/202412152358.l9RJiVaH-lkp@intel.com/
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 arch/x86/include/asm/pgtable_32.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/pgtable_32.h b/arch/x86/include/asm/pgtable_32.h
index 7d4ad8907297..3c0523588f59 100644
--- a/arch/x86/include/asm/pgtable_32.h
+++ b/arch/x86/include/asm/pgtable_32.h
@@ -56,7 +56,7 @@ do {						\
  * With PAE paging (PTRS_PER_PMD > 1), we allocate PTRS_PER_PGD == 4 pages for
  * the PMD's in addition to the pages required for the last level pagetables.
  */
-#if PTRS_PER_PMD > 1
+#if defined(PTRS_PER_PMD) && (PTRS_PER_PMD > 1)
 #define PAGE_TABLE_SIZE(pages) (((pages) / PTRS_PER_PMD) + PTRS_PER_PGD)
 #else
 #define PAGE_TABLE_SIZE(pages) ((pages) / PTRS_PER_PGD)
-- 
2.45.1.3035.g276e886db78b