Otherwise it seems like we can get stuck with concurrent waiters. Right now this /shouldn't/ be a problem, since all pending pageflip waiters are serialized by the one mode_config.mutex, so there's at most on waiter. But better paranoid than sorry, since this is tricky code. v2: WARN_ON(waitqueue_active) before waiting, as suggested by Chris Wilson. Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch> --- drivers/gpu/drm/i915/intel_display.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 390da00..74f3941 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2221,6 +2221,8 @@ intel_finish_fb(struct drm_framebuffer *old_fb) bool was_interruptible = dev_priv->mm.interruptible; int ret; + WARN_ON(waitqueue_active(&dev_priv->pending_flip_queue)); + wait_event(dev_priv->pending_flip_queue, atomic_read(&dev_priv->mm.wedged) || atomic_read(&obj->pending_flip) == 0); @@ -2888,6 +2890,8 @@ static void intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc) if (crtc->fb == NULL) return; + WARN_ON(waitqueue_active(&dev_priv->pending_flip_queue)); + wait_event(dev_priv->pending_flip_queue, !intel_crtc_has_pending_flip(crtc)); @@ -6833,7 +6837,7 @@ static void do_intel_finish_page_flip(struct drm_device *dev, obj = work->old_fb_obj; - wake_up(&dev_priv->pending_flip_queue); + wake_up_all(&dev_priv->pending_flip_queue); queue_work(dev_priv->wq, &work->work); -- 1.7.10.4