Re: [PATCH 4.4.y] drm: rcar-du: Fix crash in encoder failure error path

[Greg KH <greg@kroah.com>]

On Wed, Aug 16, 2017 at 03:53:48PM +0700, Nhan Nguyen wrote:
> From: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> 
> commit 05ee29e94acf0d4b3998c3f93374952de8f90176 upstream.
> 
> When an encoder fails to initialize the driver prints an error message
> to the kernel log. The message contains the name of the encoder's DT
> node, which is NULL for internal encoders. Use the of_node_full_name()
> macro to avoid dereferencing a NULL pointer, print the output number to
> add more context to the error, and make sure we still own a reference to
> the encoder's DT node by delaying the of_node_put() call.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
> Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
> Signed-off-by: Thong Ho <thong.ho.px@rvc.renesas.com>
> Signed-off-by: Nhan Nguyen <nhan.nguyen.yb@renesas.com>
> ---
>  drivers/gpu/drm/rcar-du/rcar_du_kms.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)

I also added this to 4.9-stable.