mm/debug_vm_pgtable.c:860 warning triggered

[Michael Ellerman]

Anshuman Khandual <anshuman.khandual at arm.com> writes:
> Hello Daniel,
>
> This test just ensures that PFN is preserved during pte <--> swap pte transformations
> , and the warning here seems to have been caused by powerpc platform specific helpers
> and/or its pte_t representation. Adding powerpc folks and platform mailing list here.

Doesn't the test need a similar treatment to:

  2321ba3e3733 ("mm/debug_vm_pgtable: more pte_swp_exclusive() sanity checks")

Which said:
    Especially, the pfn_pte() is dodgy when the swap PTE layout differs
    heavily from ordinary PTEs.  Let's properly construct a swap PTE from swap
    type+offset.


cheers