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Date:   Sat, 31 Oct 2020 16:28:13 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Kent Overstreet <kent.overstreet@gmail.com>,
        linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 05/13] mm: simplify
 generic_file_buffered_read_no_cached_page
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References: <20201031090004.452516-1-hch@lst.de>
 <20201031090004.452516-6-hch@lst.de>
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On Sat, Oct 31, 2020 at 09:59:56AM +0100, Christoph Hellwig wrote:
> +static int filemap_new_page(struct kiocb *iocb, struct iov_iter *iter,
> +		struct page **page)

I don't like this calling convention.  It's too easy to get it wrong,
as you demonstrated.  I preferred the way Kent had it with returning
an ERR_PTR.