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Date:   Fri, 11 Jun 2021 14:23:35 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Hugh Dickins <hughd@google.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Yang Shi <shy828301@gmail.com>,
        Wang Yugui <wangyugui@e16-tech.com>,
        Matthew Wilcox <willy@infradead.org>,
        Alistair Popple <apopple@nvidia.com>,
        Ralph Campbell <rcampbell@nvidia.com>, Zi Yan <ziy@nvidia.com>,
        Peter Xu <peterx@redhat.com>, Will Deacon <will@kernel.org>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 06/11] mm: page_vma_mapped_walk(): crossing page table
 boundary
Message-ID: <20210611112335.37sno6wwbsef6zen@box.shutemov.name>
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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@linux.intel.com>

-- 
 Kirill A. Shutemov