[3.4-rc1][Regression][intel] Resume from suspend to disk hangs on restoring backlight state

[Daniel Vetter]

On Mon, Apr 02, 2012 at 07:39:39PM +0200, Maciej Rutecki wrote:
> Last known good: 3.3
> Bad kernel: 3.4-rc1
> Subsystem: power management/suspend/dri(intel)
> 
> When I resume from suspend to disk then system hangs on this screen:
> http://mrutecki.pl/download/kernel/3.4-rc1/suspend_resume/DSC_5479.jpg
> 
> It does not help SysRq keys. Only I can force power off by hold power button.
> 
> Dmesg:
> http://mrutecki.pl/download/kernel/3.4-rc1/suspend_resume/dmesg-3.4-rc1.txt
> 
> Config:
> http://mrutecki.pl/download/kernel/3.4-rc1/suspend_resume/config-3.4.0-rc1

Likely a known regression, ppgtt support broke hibernate because my code
doesn't restore the ppgtt page directory correctly in the thaw function.

Patch:
http://cgit.freedesktop.org/~danvet/drm-intel/commit/?h=drm-intel-fixes&id=55a254ac63a3ac1867d1501030e7fba69c7d4aeb

Please test whether this fixes your issue. You can also try adding
i915.i915_enable_ppgtt=0 to your kernel cmdline.

Thanks, Daniel
-- 
Daniel Vetter
Mail: daniel at ffwll.ch
Mobile: +41 (0)79 365 57 48