Date:   Thu, 2 Mar 2023 17:00:18 -0500
From:   Peter Xu <peterx@redhat.com>
To:     Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc:     David Hildenbrand <david@redhat.com>, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org, Andrea Arcangeli <aarcange@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Rapoport <rppt@linux.vnet.ibm.com>,
        Axel Rasmussen <axelrasmussen@google.com>,
        Nadav Amit <nadav.amit@gmail.com>,
        "kernel@collabora.com" <kernel@collabora.com>
Subject: Re: [PATCH v2] mm/uffd: UFFD_FEATURE_WP_UNPOPULATED
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On Thu, Mar 02, 2023 at 08:14:05PM +0500, Muhammad Usama Anjum wrote:
> I've heard about a use case where a file of size 10s of GBs can be mapped
> to the memory and then accessed off and on. We need to handle this
> correctly and efficiently.

Note again that besides any slowness it'll stop working for generic FSs.

One way is we can consider enabling uffd-wp async for all archs, but I need
to think more about it, and it will not be compatible with any other modes.

-- 
Peter Xu