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Date:   Fri, 18 Mar 2022 20:36:35 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
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        Yang Shi <shy828301@gmail.com>,
        "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
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        Oded Gabbay <oded.gabbay@gmail.com>, linux-mm@kvack.org,
        Khalid Aziz <khalid.aziz@oracle.com>
Subject: Re: [PATCH v2 00/15] mm: COW fixes part 2: reliable GUP pins of
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On Tue, Mar 15, 2022 at 11:47:26AM +0100, David Hildenbrand wrote:

> This series fixes memory corruptions when a GUP pin (FOLL_PIN) was taken
> on an anonymous page and COW logic fails to detect exclusivity of the page
> to then replacing the anonymous page by a copy in the page table: The
> GUP pin lost synchronicity with the pages mapped into the page tables.

I don't know much about most of this part of the mm, but nothing here
gave me serious pause. We are trying to run this series in our RDMA
testing. Will let you know.

Thanks,
Jason