Re: [PATCH 06/11] mm: page_vma_mapped_walk(): crossing page table boundary

From: Kirill A. Shutemov
Date: Fri Jun 11 2021 - 07:23:24 EST


On Thu, Jun 10, 2021 at 04:02:47PM -0700, Hugh Dickins wrote:
> On Thu, 10 Jun 2021, Kirill A. Shutemov wrote:
> > On Wed, Jun 09, 2021 at 11:44:10PM -0700, Hugh Dickins wrote:
> > > page_vma_mapped_walk() cleanup: adjust the test for crossing page table
> > > boundary - I believe pvmw->address is always page-aligned, but nothing
> > > else here assumed that;
> >
> > Maybe we should just get it aligned instead? (PMD_SIZE - PAGE_SIZE) is not
> > most obvious mask calculation.
>
> Would you prefer it with another line of comment after the
> /* Did we cross page table boundary? */
>
> Maybe,
> /* Is address always page-aligned? No need to assume that. */
>
> I just don't see the point in forcing alignment when the test is good
> (and don't know for sure whether address is always aligned there or not).
>
> I prefer to leave it as is, just letting the commit message document it.

Okay.

Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

--
Kirill A. Shutemov