It causes black screen on bootup and is approximately 100x slower than running with FBC disabled, so the GPU runs at a high frequency for much longer - completely contrary to the power saving claims. It also still has mutex deadlocks in multi-head scenarios, which can lead to a system/X lockup. These bugs were known before FBC was enabled by default on Haswell and still have not been fixed. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=79716 Reported-and-tested-by: Jon Kristensen <info@xxxxxxxxxx> Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx --- drivers/gpu/drm/i915/intel_pm.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index e403010540a5..0b8a6010427e 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -511,8 +511,7 @@ void intel_update_fbc(struct drm_device *dev) obj = intel_fb->obj; adjusted_mode = &intel_crtc->config.adjusted_mode; - if (i915.enable_fbc < 0 && - INTEL_INFO(dev)->gen <= 7 && !IS_HASWELL(dev)) { + if (i915.enable_fbc < 0) { if (set_no_fbc_reason(dev_priv, FBC_CHIP_DEFAULT)) DRM_DEBUG_KMS("disabled per chip default\n"); goto out_disable; -- 2.0.0 -- 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