Hi Paolo, On Wed, Feb 12, 2020 at 01:25:30PM +0100, Paolo Bonzini wrote: > MIPS folks, I see that arch/mips/kvm/mmu.c uses pud_index, so it's not > clear to me if it's meant to only work if CONFIG_PGTABLE_LEVELS=4 or > it's just bit rot. Should I add a "depends on PGTABLE_LEVEL=4" to > arch/mips/Kconfig? I'm no expert on this bit of code, but I'm pretty sure the systems KVM/VZ has been used on the most internally had PGTABLE_LEVEL=3. I suspect this is actually a regression from commit 31168f033e37 ("mips: drop __pXd_offset() macros that duplicate pXd_index() ones"). Whilst that commit is correct that pud_index() & __pud_offset() are the same when pud_index() is actually provided, it doesn't take into account the __PAGETABLE_PUD_FOLDED case. There __pud_offset() was available but would always evaluate to zero, whereas pud_index() isn't defined... Thanks, Paul