Re: [PATCH] drm/amd/display: Fail atomic_check early on normalize_zpos error

[Hamza Mahfooz <hamza.mahfooz@amd.com>]

On 2/13/23 10:51, sunpeng.li@amd.com wrote:
> From: Leo Li <sunpeng.li@amd.com>
> 
> [Why]
> 
> drm_atomic_normalize_zpos() can return an error code when there's
> modeset lock contention. This was being ignored.
> 
> [How]
> 
> Bail out of atomic check if normalize_zpos() returns an error.
> 
> Fixes: b261509952bc ("drm/amd/display: Fix double cursor on non-video RGB MPO")
> Signed-off-by: Leo Li <sunpeng.li@amd.com>
> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>

Cc: stable@vger.kernel.org

Reviewed-by: Hamza Mahfooz <hamza.mahfooz@amd.com>

> ---
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index c10982f841f98..cb2a57503000d 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -9889,7 +9889,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>   	 * `dcn10_can_pipe_disable_cursor`). By now, all modified planes are in
>   	 * atomic state, so call drm helper to normalize zpos.
>   	 */
> -	drm_atomic_normalize_zpos(dev, state);
> +	ret = drm_atomic_normalize_zpos(dev, state);
> +	if (ret) {
> +		drm_dbg(dev, "drm_atomic_normalize_zpos() failed\n");
> +		goto fail;
> +	}
>   
>   	/* Remove exiting planes if they are modified */
>   	for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {

-- 
Hamza