Re: [BISECTED REGRESSION in 3.19-rc1] [drm/i915] WARNING: drivers/gpu/drm/drm_irq.c:1077 drm_wait_one_vblank

Jani Nikula
2015-02-23T12:44:43Z

On Mon, 16 Feb 2015, Paul Bolle <pebolle@tiscali.nl> wrote:
> I still see this on v3.19. I booted with drm.debug=0x4. The almost 2K
> lines in dmesg containing either "[drm" or this WARNING are pasted
> below. I really know nothing about all this, but I do note that only the
> WARNINGS are preceded by:
> [drm:intel_calculate_wm] FIFO watermark level: -5
> [drm:i9xx_update_wm] FIFO watermarks - A: 26, B: 8
>
> But perhaps that's another symptom of the same issue. A bit of staring
> at the code couldn't help me determine that.
>
> Perhaps these debug messages help someone in discovering what might be
> going on here.

Please try v4.0-rc1 or try cherry-picking this on top of v3.19 and
report back:

commit f9b61ff6bce9a44555324b29e593fdffc9a115bc
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Wed Jan 7 13:54:39 2015 +0100

drm/i915: Push vblank enable/disable past encoder->enable/disable

BR,
Jani.

--
Jani Nikula, Intel Open Source Technology Center