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Date:   Tue, 26 Apr 2022 20:06:50 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Stefan Roesch <shr@fb.com>
Cc:     io-uring@vger.kernel.org, kernel-team@fb.com, linux-mm@kvack.org,
        linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        david@fromorbit.com
Subject: Re: [RFC PATCH v1 02/18] mm: add FGP_ATOMIC flag to
 __filemap_get_folio()
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References: <20220426174335.4004987-1-shr@fb.com>
 <20220426174335.4004987-3-shr@fb.com>
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On Tue, Apr 26, 2022 at 10:43:19AM -0700, Stefan Roesch wrote:
> Define FGP_ATOMIC flag and add support for the new flag in the function
> __filemap_get_folio().

No.  You don't get to use the emergency memory pools for doing writes.
That completely screws up the MM.