[Intel-gfx] [PATCH 1/7] drm/i915: Avoid the gpu reset vs. modeset deadlock

[Daniel Vetter]

On Thu, Jul 20, 2017 at 9:47 PM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index 02b1f4966049..995522e40ec1 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -3471,6 +3471,12 @@ void intel_prepare_reset(struct drm_i915_private *dev_priv)
>>             !gpu_reset_clobbers_display(dev_priv))
>>                 return;
>>
>> +       /* We have a modeset vs reset deadlock, defensively unbreak it.
>> +        *
>> +        * FIXME: We can do a _lot_ better, this is just a first iteration.*/
>> +       i915_gem_set_wedged(dev_priv);
>> +       DRM_DEBUG_DRIVER("Wedging GPU to avoid deadlocks with pending modeset updates\n");
>
> I meant this a dev_err(). It has user visible impact and user data loss.

stop_rings is gone so I can't differentiate, and DRM_ERROR breaks CI.
Which after your timeout is the only point of this patch really. I
guess I could throw a pr_notice or so in there, but we already do
that. This was all removed in

commit 7b4d3a16dd97be0ebc793ea046b9af9d5c9b1b1a
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Mon Jul 4 08:08:37 2016 +0100

    drm/i915: Remove stop-rings debugfs interface

Should I explain this better in the commit message? I tried already ...
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch