Re: [PATCH 10/10] mm, treewide: Redefine MAX_ORDER sanely

From: Michael Ellerman
Date: Tue Mar 21 2023 - 23:27:13 EST


"Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> writes:
> MAX_ORDER currently defined as number of orders page allocator supports:
> user can ask buddy allocator for page order between 0 and MAX_ORDER-1.
>
> This definition is counter-intuitive and lead to number of bugs all over
> the kernel.
>
> Change the definition of MAX_ORDER to be inclusive: the range of orders
> user can ask from buddy allocator is 0..MAX_ORDER now.
>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
> ---
...
> arch/powerpc/Kconfig | 27 ++++++-------
> arch/powerpc/configs/85xx/ge_imp3a_defconfig | 2 +-
> arch/powerpc/configs/fsl-emb-nonhw.config | 2 +-
> arch/powerpc/mm/book3s64/iommu_api.c | 2 +-
> arch/powerpc/mm/hugetlbpage.c | 2 +-
> arch/powerpc/platforms/powernv/pci-ioda.c | 2 +-

Reviewed-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> (powerpc)

cheers