linux-kernel - Re: [PATCH] virtio-gpu: fix output lookup

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Message-ID: <20160530151916.GR27098@phenom.ffwll.local>
Date:	Mon, 30 May 2016 17:19:16 +0200
From:	Daniel Vetter <daniel@...ll.ch>
To:	Gerd Hoffmann <kraxel@...hat.com>
Cc:	dri-devel@...hat.com, open list <linux-kernel@...r.kernel.org>,
	"open list:VIRTIO GPU DRIVER" <dri-devel@...ts.freedesktop.org>,
	"open list:VIRTIO GPU DRIVER" 
	<virtualization@...ts.linux-foundation.org>
Subject: Re: [PATCH] virtio-gpu: fix output lookup

On Mon, May 30, 2016 at 02:03:26PM +0200, Gerd Hoffmann wrote:
> Needed for multihead setups where we can have disabled
> outputs and therefore plane->crtc can be NULL.
> 
> Signed-off-by: Gerd Hoffmann <kraxel@...hat.com>

See my reply in the other thread, but I think you have a more fundamental
issue here. I dropped two suggestions worth trying, both need your own
atomic_commit_tail (on top of my branch at least):
- set active_only to true in commit_planes()
- move commit_planes after commit_modeset_enables().

Cheers, Daniel
> ---
>  drivers/gpu/drm/virtio/virtgpu_plane.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/virtio/virtgpu_plane.c b/drivers/gpu/drm/virtio/virtgpu_plane.c
> index 70b44a2..e50674b 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_plane.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_plane.c
> @@ -63,11 +63,17 @@ static void virtio_gpu_plane_atomic_update(struct drm_plane *plane,
>  {
>  	struct drm_device *dev = plane->dev;
>  	struct virtio_gpu_device *vgdev = dev->dev_private;
> -	struct virtio_gpu_output *output = drm_crtc_to_virtio_gpu_output(plane->crtc);
> +	struct virtio_gpu_output *output = NULL;
>  	struct virtio_gpu_framebuffer *vgfb;
>  	struct virtio_gpu_object *bo;
>  	uint32_t handle;
>  
> +	if (plane->state->crtc)
> +		output = drm_crtc_to_virtio_gpu_output(plane->state->crtc);
> +	if (old_state->crtc)
> +		output = drm_crtc_to_virtio_gpu_output(old_state->crtc);
> +	WARN_ON(!output);
> +
>  	if (plane->state->fb) {
>  		vgfb = to_virtio_gpu_framebuffer(plane->state->fb);
>  		bo = gem_to_virtio_gpu_obj(vgfb->obj);
> -- 
> 1.8.3.1
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@...ts.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch

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