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Date:   Mon, 18 Sep 2023 15:00:09 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Hannes Reinecke <hare@suse.de>
Cc:     Luis Chamberlain <mcgrof@kernel.org>,
        Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        Pankaj Raghav <p.raghav@samsung.com>,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 09/18] fs/buffer: use mapping order in grow_dev_page()
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On Mon, Sep 18, 2023 at 01:05:01PM +0200, Hannes Reinecke wrote:
> Use the correct mapping order in grow_dev_page() to ensure folios
> are created with the correct order.

I see why you did this, but I think it's fragile.  __filemap_get_folio()
will happily decrease 'order' if memory allocation fails.  I think
__filemap_get_folio() needs to become aware of the minimum folio
order for this mapping, and then we don't need this patch.

Overall, I like bits of this patchset and I like bits of Pankaj's ;-)