On Sat, Nov 18, 2017 at 01:47:32PM +0100, Rainer Fiebig wrote: > Hi! > > Hopefully the right addressee. > > Encountered two bad backports which cause screen-flicker. > dmesg shows: > > ... > [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun > [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder A FIFO underrun > [drm:ironlake_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun > [drm:ironlake_irq_handler [i915]] *ERROR* PCH transcoder B FIFO underrun > ... > > CPU: Intel Core i3 (Clarkdale/Ironlake) > > The backports are: > > - diff --git a/drivers/gpu/drm/i915/intel_pm.c > b/drivers/gpu/drm/i915/intel_pm.c > index 49de476..277a802 100644 > - diff --git a/drivers/gpu/drm/i915/intel_drv.h > b/drivers/gpu/drm/i915/intel_drv.h > index a19ec06..3ce9ba3 100644 > > After reversing them the flicker is gone, no more messages in dmesg. All > else OK so far. So which commit was the one that caused the problem? I will be glad to revert it. thanks, greg k-h