pte_alloc_one() ends up calling pte_fragment_alloc(mm, 0). But there we always
end up calling pagetable_alloc(, 0).
And fragments are supposed to be <= a single page.
Now I'm confused what's wrong here ... am I missing something obvious?
CCing some powerpc folks. Is this some pte_t oddity?
It will be because PTRS_PER_PTE is not a compile time constant :(
Oh, sneaky! Thanks a bunch!
$ git grep "define PTRS_PER_PTE" arch/powerpc/include/asm/book3s/64
arch/powerpc/include/asm/book3s/64/pgtable.h:#define PTRS_PER_PTE (1 << PTE_INDEX_SIZE)
$ git grep "define PTE_INDEX_SIZE" arch/powerpc/include/asm/book3s/64
arch/powerpc/include/asm/book3s/64/pgtable.h:#define PTE_INDEX_SIZE __pte_index_size
$ git grep __pte_index_size arch/powerpc/mm/pgtable_64.c
arch/powerpc/mm/pgtable_64.c:unsigned long __pte_index_size;
Which is because the pseries/powernv (book3s64) kernel supports either
the HPT or Radix MMU at runtime, and they have different page table
geometry.
If you change it to use MAX_PTRS_PER_PTE it should work (that's defined
for all arches).
Yes, that should fly, thanks again!
--
Cheers,
David / dhildenb
