Re: [PATCH] dma-buf: add support for compat ioctl

[Marek Szyprowski]

Hi Christian,

On 2017-02-21 14:59, Christian KÃnig wrote:
> Am 21.02.2017 um 14:21 schrieb Marek Szyprowski:
> > Add compat ioctl support to dma-buf. This lets one to use 
> > DMA_BUF_IOCTL_SYNC
> > ioctl from 32bit application on 64bit kernel. Data structures for 
> > both 32
> > and 64bit modes are same, so there is no need for additional translation
> > layer.
>
> Well I might be wrong, but IIRC compat_ioctl was just optional and if 
> not specified unlocked_ioctl was called instead.
>
> If that is true your patch wouldn't have any effect at all.

Well, then why I got -ENOTTY in the 32bit test app for this ioctl on 
64bit ARM64 kernel without this patch?

Best regards
--
Marek Szyprowski, PhD
Samsung R&D Institute Poland