Am 29.03.2017 um 06:00 schrieb raof at ubuntu.com:
> From: Christopher James Halse Rogers <christopher.halse.rogers at canonical.com>
>
> Any use of the framebuffer will migrate it to VRAM, which is not sensible for
> an imported dma-buf.
>
> v2: Use DRM_DEBUG_KMS to prevent userspace accidentally spamming dmesg.
>
> Signed-off-by: Christopher James Halse Rogers <christopher.halse.rogers at canonical.com>
> CC: amd-gfx at lists.freedesktop.org
For this one and the amdgpu variant: Reviewed-by: Christian König
<christian.koenig at amd.com>.
> ---
> drivers/gpu/drm/radeon/radeon_display.c | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
> index aea8b62835a4..f85e9c1eaa47 100644
> --- a/drivers/gpu/drm/radeon/radeon_display.c
> +++ b/drivers/gpu/drm/radeon/radeon_display.c
> @@ -1352,6 +1352,12 @@ radeon_user_framebuffer_create(struct drm_device *dev,
> return ERR_PTR(-ENOENT);
> }
>
> + /* Handle is imported dma-buf, so cannot be migrated to VRAM for scanout */
> + if (obj->import_attach) {
> + DRM_DEBUG_KMS("Cannot create framebuffer from imported dma_buf\n");
> + return ERR_PTR(-EINVAL);
> + }
> +
> radeon_fb = kzalloc(sizeof(*radeon_fb), GFP_KERNEL);
> if (radeon_fb == NULL) {
> drm_gem_object_unreference_unlocked(obj);
