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From:   Brian Geffon <bgeffon@google.com>
Date:   Sun, 2 Feb 2020 05:17:53 +0100
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Subject: Re: [PATCH v2] mm: Add MREMAP_DONTUNMAP to mremap().
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        "Michael S . Tsirkin" <mst@redhat.com>,
        Arnd Bergmann <arnd@arndb.de>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>, linux-api@vger.kernel.org,
        Andy Lutomirski <luto@amacapital.net>,
        Andrea Arcangeli <aarcange@redhat.com>,
        Sonny Rao <sonnyrao@google.com>,
        Minchan Kim <minchan@kernel.org>,
        Joel Fernandes <joel@joelfernandes.org>,
        Yu Zhao <yuzhao@google.com>, Jesse Barnes <jsbarnes@google.com>
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On Wed, Jan 29, 2020 at 11:46 AM Kirill A. Shutemov
<kirill@shutemov.name> wrote:
> Any better options for the flag name? (I have none)

The other option is that it's broken up into two new flags the first
MREMAP_MUSTMOVE which can be used regardless of whether or not you're
leaving the original mapping mapped. This would do exactly what it
describes: move the mapping to a new address with or without
MREMAP_FIXED, this keeps consistency with MAYMOVE.

The second flag would be the new MREMAP_DONTUNMAP flag which requires
MREMAP_MUSTMOVE, again with or without MREMAP_FIXED.

What are your thoughts on this?