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Date:   Mon, 21 Sep 2020 16:07:45 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Christoph Hellwig <hch@lst.de>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
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Subject: Re: [PATCH 04/11] iov_iter: explicitly check for CHECK_IOVEC_ONLY in
 rw_copy_check_uvector
Message-ID: <20200921150745.GT3421308@ZenIV.linux.org.uk>
References: <20200921143434.707844-1-hch@lst.de>
 <20200921143434.707844-5-hch@lst.de>
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On Mon, Sep 21, 2020 at 04:34:27PM +0200, Christoph Hellwig wrote:
> Explicitly check for the magic value insted of implicitly relying on
> its numeric representation.   Also drop the rather pointless unlikely
> annotation.

See above - I would rather have CHECK_IOVEC_ONLY gone.

The reason for doing these access_ok() in the same loop is fairly weak,
especially since you are checking type on each iteration.  Might as
well do that in a separate loop afterwards.