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Date:   Wed, 20 Oct 2021 04:19:30 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     "Kirill A. Shutemov" <kirill@shutemov.name>,
        Kent Overstreet <kent.overstreet@gmail.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        "Darrick J. Wong" <djwong@kernel.org>,
        Christoph Hellwig <hch@infradead.org>,
        David Howells <dhowells@redhat.com>,
        Hugh Dickins <hughd@google.com>
Subject: Re: Folios for 5.15 request - Was: re: Folio discussion recap -
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On Tue, Oct 19, 2021 at 11:16:18AM -0400, Johannes Weiner wrote:
> My only effort from the start has been working out unanswered
> questions in this proposal: Are compound pages the reliable, scalable,
> and memory-efficient way to do bigger page sizes? What's the scope of
> remaining tailpages where typesafety will continue to lack? How do we
> implement code and properties shared by folios and non-folio types
> (like mmap/fault code for folio and network and driver pages)?

I don't think those questions need to be answered before proceeding
with this patchset.  They're interesting questions, to be sure, but
to a large extent they're orthogonal to the changes here.  I look
forward to continuing to work on those problems while filesystems
and the VFS continue to be converted to use folios.

> I'm not really sure how to exit this. The reasons for my NAK are still
> there. But I will no longer argue or stand in the way of the patches.

Thank you.  I appreciate that.