On 8/15/19 6:03 AM, Aleix Roca Nonell wrote:
> Commit bd11b3a391e3 ("io_uring: don't use iov_iter_advance() for fixed
> buffers") introduced an optimization to avoid using the slow
> iov_iter_advance by manually populating the iov_iter iterator in some
> cases.
>
> However, the computation of the iterator count field was erroneous: The
> first bvec was always accounted for an extent of page size even if the
> bvec length was smaller.
>
> In consequence, some I/O operations on fixed buffers were unable to
> operate on the full extent of the buffer, consistently skipping some
> bytes at the end of it.
Applied, thanks.
--
Jens Axboe
