On Mon, Aug 17, 2020 at 09:32:03AM +0200, Christoph Hellwig wrote:

Don't allow calling ->read or ->write with set_fs as a preparation for
killing off set_fs.  All the instances that we use kernel_read/write on
are using the iter ops already.

If a file has both the regular ->read/->write methods and the iter
variants those could have different semantics for messed up enough
drivers.  Also fails the kernel access to them in that case.

Signed-off-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: Kees Cook <redacted>

-- 
Kees Cook