3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> commit 7317c75e66fce0c9f82fbe6f72f7e5256b315422 upstream. This fixes a race where we may try to finish a page flip and decrement the refcount even if our vblank_get failed and we ended up with a spurious flip pending interrupt. Fixes https://bugs.freedesktop.org/show_bug.cgi?id=34211. Signed-off-by: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> Signed-off-by: Keith Packard <keithp@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -6524,11 +6524,16 @@ static int intel_crtc_page_flip(struct d work->old_fb_obj = intel_fb->obj; INIT_WORK(&work->work, intel_unpin_work_fn); + ret = drm_vblank_get(dev, intel_crtc->pipe); + if (ret) + goto free_work; + /* We borrow the event spin lock for protecting unpin_work */ spin_lock_irqsave(&dev->event_lock, flags); if (intel_crtc->unpin_work) { spin_unlock_irqrestore(&dev->event_lock, flags); kfree(work); + drm_vblank_put(dev, intel_crtc->pipe); DRM_DEBUG_DRIVER("flip queue: crtc already busy\n"); return -EBUSY; @@ -6547,10 +6552,6 @@ static int intel_crtc_page_flip(struct d crtc->fb = fb; - ret = drm_vblank_get(dev, intel_crtc->pipe); - if (ret) - goto cleanup_objs; - work->pending_flip_obj = obj; work->enable_stall_check = true; @@ -6572,7 +6573,6 @@ static int intel_crtc_page_flip(struct d cleanup_pending: atomic_sub(1 << intel_crtc->plane, &work->old_fb_obj->pending_flip); -cleanup_objs: drm_gem_object_unreference(&work->old_fb_obj->base); drm_gem_object_unreference(&obj->base); mutex_unlock(&dev->struct_mutex); @@ -6581,6 +6581,8 @@ cleanup_objs: intel_crtc->unpin_work = NULL; spin_unlock_irqrestore(&dev->event_lock, flags); + drm_vblank_put(dev, intel_crtc->pipe); +free_work: kfree(work); return ret; -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html