[Intel-gfx] [PATCH] Revert "drm/i915: Lock mode_config.mutex in intel_display_resume."

[Daniel Vetter]

On Tue, Apr 04, 2017 at 03:22:48PM +0200, Maarten Lankhorst wrote:
> This reverts commit ea49c9acf2db7082f0406bb3a570cc6bad37082b.
> 
> mode_config.mutex was originally added to fix WARNs in connector
> functions, but now that atomic nonblocking modeset support is
> included, we will likely never hold any any lock at all.
> 
> The WARN mentioned in commit bbf35e9defb9a6d1 ("drm/i915:
> Pass atomic state to intel_audio_codec_enable, v2."), so it's
> safe to revert this now.
> 
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>

Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>

I think you can push that right after the backmerge went out.
-Daniel

> ---
>  drivers/gpu/drm/i915/intel_display.c | 8 --------
>  1 file changed, 8 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 65aa8e586ec5..4698503c156b 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -15606,13 +15606,6 @@ void intel_display_resume(struct drm_device *dev)
>  	if (state)
>  		state->acquire_ctx = &ctx;
>  
> -	/*
> -	 * This is a cludge because with real atomic modeset mode_config.mutex
> -	 * won't be taken. Unfortunately some probed state like
> -	 * audio_codec_enable is still protected by mode_config.mutex, so lock
> -	 * it here for now.
> -	 */
> -	mutex_lock(&dev->mode_config.mutex);
>  	drm_modeset_acquire_init(&ctx, 0);
>  
>  	while (1) {
> @@ -15628,7 +15621,6 @@ void intel_display_resume(struct drm_device *dev)
>  
>  	drm_modeset_drop_locks(&ctx);
>  	drm_modeset_acquire_fini(&ctx);
> -	mutex_unlock(&dev->mode_config.mutex);
>  
>  	if (ret)
>  		DRM_ERROR("Restoring old state failed with %i\n", ret);
> -- 
> 2.7.4
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

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