[Intel-gfx] [PATCH] drm/i915: Fix irq enable tracking in driver load

[Daniel Vetter]

On Thu, Sep 04, 2014 at 02:12:10PM +0300, Jani Nikula wrote:
> On Wed, 27 Aug 2014, Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> > A bunch of warnings fire on some ->irq_postinstall hooks since those
> > can enable interrupts (e.g. rps interrupts). And then our ordering
> > self-checks fire and complain.
> >
> > To fix that set the tracking boolen before enabling the irqs witho
> > drm_irq_install. Quoting the discussion with Jesse why that's safe:
> 
> Yi Sun's testing result needs to be addressed one way or another before
> merging this:
> 
> http://mid.gmane.org/D9F66AA509623343B6A9A3D4502D5A52112B0676@SHSMSX101.ccr.corp.intel.com

Shrug it off as an unstable test result. Both mine and Jesse's patch
really only change the logic we use to WARN about interrupt state. We
don't use pm._irqs_disabled for anything else at all.

Which means that black screen is at most a timing issue. Or the baseline
kernels don't perfectly match (the new warning in Jesse's patch is a bit
an indicator for that).
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch