On Mon, Jun 3, 2019 at 12:41 AM Christoph Hellwig <hch@xxxxxx> wrote:
>
> I only removed a duplicate of it.
I don't see any remaining cases.
> The full (old) code in get_user_pages_fast() looks like this:
>
> if (nr_pages <= 0)
> return 0;
>
> if (unlikely(!access_ok((void __user *)start, len)))
> return -EFAULT;
>
> if (gup_fast_permitted(start, nr_pages)) {
Yes, and that code was correct.
The new code has no test at all for "nr_pages == 0", afaik.
Linus
