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Date:   Wed, 23 Dec 2020 12:11:36 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Christoph Hellwig <hch@infradead.org>
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Subject: Re: [PATCH] mm: add prototype for __add_to_page_cache_locked()
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On Wed, Dec 23, 2020 at 08:31:26AM +0000, Christoph Hellwig wrote:
> Can we please make the eBPF code stop referencing this function instead
> of papering over this crap?  It has no business poking into page cache
> internals.

The reference from the BPF code is simply "you can inject errors here".
And I think we want to be able to inject errors to test the error paths,
no?