PUD_MASKED_BITS   252 arch/powerpc/include/asm/book3s/64/pgtable.h #define PUD_MASKED_BITS		0xc0000000000000ffUL
PUD_MASKED_BITS    47 arch/powerpc/include/asm/nohash/64/pgtable-4k.h #define PUD_MASKED_BITS		0