2018-04-30 15:16:27

by Joseph Salisbury

Subject: [REGRESSION] drm/amd/dc: Add dc display driver (v2)

Hi Harry,

A kernel bug report was opened against Ubuntu [0].  After a kernel
bisect, it was found the following commit introduced the bug:


commit 4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c
Author: Harry Wentland <[email protected]>
Date:   Tue Sep 12 15:58:20 2017 -0400

    drm/amd/dc: Add dc display driver (v2)


The regression was introduced as of v4.15-rc1 and still exists in
current mainline.  The commit does not need to be reverted to resolve
the bug.  Disabling the CONFIG_DRM_AMD_DC_PRE_VEGA option makes the bug
go away.
   
I was hoping to get your feedback, since you are the patch author.  Do
you think gathering any additional data will help diagnose this issue?
   

Thanks,

Joe


[0] http://pad.lv/1761751

2018-04-30 15:42:37

by Harry Wentland

Subject: Re: [REGRESSION] drm/amd/dc: Add dc display driver (v2)

Replied on the ticket.

If this is about non-functioning LVDS or VGA I'm aware of it and trying to find time to find a good solution.

Harry

On 2018-04-30 11:14 AM, Joseph Salisbury wrote:
> Hi Harry,
>
> A kernel bug report was opened against Ubuntu [0].  After a kernel
> bisect, it was found the following commit introduced the bug:
>
>
> commit 4562236b3bc0a28aeb6ee93b2d8a849a4c4e1c7c
> Author: Harry Wentland <[email protected]>
> Date:   Tue Sep 12 15:58:20 2017 -0400
>
>     drm/amd/dc: Add dc display driver (v2)
>
>
> The regression was introduced as of v4.15-rc1 and still exists in
> current mainline.  The commit does not need to be reverted to resolve
> the bug.  Disabling the CONFIG_DRM_AMD_DC_PRE_VEGA option makes the bug
> go away.
>    
> I was hoping to get your feedback, since you are the patch author.  Do
> you think gathering any additional data will help diagnose this issue?
>    
>
> Thanks,
>
> Joe
>
>
> [0] http://pad.lv/1761751
>