Re: [PATCH] x86: numa: drop ZONE_ALIGN

David Rientjes
2014-06-11T22:54:02Z

On Wed, 11 Jun 2014, Christoph Lameter wrote:

> > > The zone should not cross the 8M boundary?
> >
> > Yes, but the question is: why?
>
> zones need to be aligned so that the huge pages order and other page
> orders allocated from the page allocator are at their "natural alignment".
> Otherwise huge pages cannot be mapped properly and various I/O devices
> may encounter issues if they rely on the natural alignment.
>

Any reason not to align to HUGETLB_PAGE_ORDER on x86 instead of
ZONE_ALIGN?