[PATCH] drm/atomic: put commit when -ERESTARTSYS received

[Daniel Vetter]

On Thu, Aug 17, 2017 at 10:21:18AM -0400, Jerry Zuo wrote:
> During page flip atomic_check and atomic_commit can return
> -ERESTARTSYS to restart the ioctl. When this happens we fail to
> put the commit object leading to a memory leak.
> 
> v2: Changed subject tag to drm/atomic
> 
> Signed-off-by: Jerry Zuo <Jerry.Zuo at amd.com>

When resubmitting pls cc: everyone involved and cc'ed in the old
discussion. Still looking for that testcase, please have a chat with
Maarten over irc or so. 
-Daniel

> ---
>  drivers/gpu/drm/drm_atomic.c | 25 +++++++++++++++++++++++--
>  1 file changed, 23 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index f32506a7c1d6..f2f623dacf90 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -1642,14 +1642,35 @@ int drm_atomic_nonblocking_commit(struct drm_atomic_state *state)
>  {
>  	struct drm_mode_config *config = &state->dev->mode_config;
>  	int ret;
> +	int i;
> +	struct drm_crtc *crtc;
> +	struct drm_crtc_state *crtc_state;
>  
>  	ret = drm_atomic_check_only(state);
> -	if (ret)
> +	if (ret) {
> +		if (ret == -ERESTARTSYS)
> +			goto fail;
> +
>  		return ret;
> +	}
>  
>  	DRM_DEBUG_ATOMIC("commiting %p nonblocking\n", state);
>  
> -	return config->funcs->atomic_commit(state->dev, state, true);
> +	ret = config->funcs->atomic_commit(state->dev, state, true);
> +	if (ret == -ERESTARTSYS)
> +		goto fail;
> +
> +	return ret;
> +
> +	/* cleanup commit object if commit fails with ERESTARTSYS */
> +fail:
> +	for_each_crtc_in_state(state, crtc, crtc_state, i) {
> +		if (state->crtcs[i].commit) {
> +			drm_crtc_commit_put(state->crtcs[i].commit);
> +		}
> +	}
> +
> +	return ret;
>  }
>  EXPORT_SYMBOL(drm_atomic_nonblocking_commit);
>  
> -- 
> 2.11.0
> 

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