kernel BUG at drivers/gpu/drm//ttm/ttm_bo.c:196!

[Christian König]

Am 05.02.19 um 18:40 schrieb Michel Dänzer:
> On 2019-02-05 4:45 p.m., Christian König wrote:
>> Possible, but unlikely.
>>
>> That sounds more like a reference counting problem where something is
>> killing the BO while it is still on the LRU.
> FWIW, I've hit this twice now today, whereas I don't remember ever
> hitting it before (not 100% sure though).
>
> I reverted the remaining hunk of the "cleanup setting bulk_movable"
> change, and it survived a piglit run. Could just be luck, though...

Did you have KASAN enabled?

The only possible explanation I have is that we either somehow corrupt 
the counter or try to free a BO twice. Both should be recognized 
immediately by KASAN.

Christian.