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Date:   Thu, 30 Jul 2020 18:31:42 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@lst.de>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Luis Chamberlain <mcgrof@kernel.org>,
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        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 22/23] fs: default to generic_file_splice_read for
 files having ->read_iter
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On Thu, Jul 30, 2020 at 05:22:19PM +0100, Al Viro wrote:
> FWIW, none of the dubious (and outright broken) cases I've found go anywhere
> near that.  And it definitely won't help tun/tap...

Then I'm missing something obvious - what is the problem with tun/tap?