The page table check feature requires that pud_pfn() be defined
on each consuming architecture. Since only 64-bit, Book3S platforms
allow for hugepages at this upper level, and since the calling code is
gated by a call to pud_user_accessible_page(), which will return zero,
include this stub as a BUILD_BUG().

Signed-off-by: Rohan McLure <redacted>
---
v11: pud_pfn() stub has been removed upstream as it has valid users now
in transparent hugepages. Create a BUG_ON() for other, non Book3S64
platforms.
---
  arch/powerpc/include/asm/pgtable.h | 8 ++++++++
  1 file changed, 8 insertions(+)

diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h
index 239709a2f68e..ee8c82c0528f 100644
--- a/arch/powerpc/include/asm/pgtable.h
+++ b/arch/powerpc/include/asm/pgtable.h

@@ -211,6 +211,14 @@ static inline bool arch_supports_memmap_on_memory(unsigned long vmemmap_size)
  
  #endif /* CONFIG_PPC64 */
  
+#ifndef pud_pfn
+#define pud_pfn pud_pfn
+static inline int pud_pfn(pud_t pud)
+{
+	BUILD_BUG();