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From: Christoph Hellwig <hch@lst.de>
To: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: [PATCH 03/16] mm: simplify gup_fast_permitted
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Cc: Rich Felker <dalias@libc.org>, Yoshinori Sato <ysato@users.sourceforge.jp>,
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On Mon, Jun 03, 2019 at 10:02:10AM -0700, Linus Torvalds wrote:
> On Mon, Jun 3, 2019 at 9:08 AM Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > The new code has no test at all for "nr_pages == 0", afaik.
> 
> Note that it really is important to check for that, because right now we do

True.  The 0 check got lost.  I'll make sure we do the right thing for
the next version.