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Date: Wed, 28 Nov 2018 18:42:22 -0800
From: Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH] mm: remove pte_lock_deinit()
Message-ID: <20181129024222.GJ10377@bombadil.infradead.org>
References: <20181128235525.58780-1-yuzhao@google.com>
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To: Yu Zhao <yuzhao@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, Hugh Dickins <hughd@google.com>, "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>, Michal Hocko <mhocko@suse.com>, Dan Williams <dan.j.williams@intel.com>, Pavel Tatashin <pasha.tatashin@oracle.com>, Souptick Joarder <jrdr.linux@gmail.com>, Logan Gunthorpe <logang@deltatee.com>, Keith Busch <keith.busch@intel.com>, linux-mm@kvack.org, linux-kernel@vger.kernel.org

On Wed, Nov 28, 2018 at 04:55:25PM -0700, Yu Zhao wrote:
> Pagetable page doesn't touch page->mapping or have any used field
> that overlaps with it. No need to clear mapping in dtor. In fact,
> doing so might mask problems that otherwise would be detected by
> bad_page().
> 
> Signed-off-by: Yu Zhao <yuzhao@google.com>

Reviewed-by: Matthew Wilcox <willy@infradead.org>

I do have plans to use page->mapping for pt_mm, but this patch won't
get in my way when I find the round tuits to do that work.