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Date:   Mon, 6 Mar 2023 17:40:04 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Hannes Reinecke <hare@suse.de>
Cc:     Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
        Luis Chamberlain <mcgrof@kernel.org>,
        Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCH 4/5] brd: limit maximal block size to 32M
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On Mon, Mar 06, 2023 at 01:01:26PM +0100, Hannes Reinecke wrote:
> Use an arbitrary limit of 32M for the maximal blocksize so as not
> to overflow the page cache.

The page allocator tops out at MAX_ORDER (generally 4MB), so that might
be a better limit.  Also, this has nothing to do with the page cache,
right?