On Sat, Apr 06, 2013 at 11:54:56PM +0200, Daniel Vetter wrote:
> Userspace can easily hit this and does since Ville added a new evil
> igt testcase in:
>
> commit 069e35e0fc3785faa562adcfd2dd7bbed4cb1dea
> Author: Ville Syrj?l? <ville.syrjala at linux.intel.com>
> Date: Mon Mar 4 15:34:06 2013 +0200
>
> kms_flip: Add flip-vs-bad-tiling test
>
> v2: Fix the spelling in the added comment (Chris).
>
> Cc: Ville Syrj?l? <ville.syrjala at linux.intel.com>
> Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
I've picked this up for next with a reference to the bug QA filed.
-Daniel
> ---
> drivers/gpu/drm/i915/intel_display.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 1b2c744..0e799ea 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -1907,8 +1907,10 @@ intel_pin_and_fence_fb_obj(struct drm_device *dev,
> alignment = 0;
> break;
> case I915_TILING_Y:
> - /* FIXME: Is this true? */
> - DRM_ERROR("Y tiled not allowed for scan out buffers\n");
> + /* Despite that we check this in framebuffer_init userspace can
> + * screw us over and change the tiling after the fact. Only
> + * pinned buffers can't change their tiling. */
> + DRM_DEBUG_DRIVER("Y tiled not allowed for scan out buffers\n");
> return -EINVAL;
> default:
> BUG();
> --
> 1.7.10.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
