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Date:   Fri, 1 Jul 2022 21:24:03 -0700
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Khalid Aziz <khalid.aziz@oracle.com>
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Subject: Re: [PATCH v2 0/9] Add support for shared PTEs across processes
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On Wed, 29 Jun 2022 16:53:51 -0600 Khalid Aziz <khalid.aziz@oracle.com> wrote:

> This patch series implements a mechanism in kernel to allow
> userspace processes to opt into sharing PTEs. It adds a new
> in-memory filesystem - msharefs. 

Dumb question: why do we need a new filesystem for this?  Is it not
feasible to permit PTE sharing for mmaps of tmpfs/xfs/ext4/etc files?