Re: [PATCH 03/15] dma-buf & drm/amdgpu: remove dma_resv workaround

["Christian König" <ckoenig.leichtzumerken@gmail.com>]

Am 20.04.22 um 19:38 schrieb Zack Rusin:
> On Wed, 2022-04-20 at 09:37 +0200, Christian König wrote:
>> ⚠ External Email
>>
>> Hi Zack,
>>
>> Am 20.04.22 um 05:56 schrieb Zack Rusin:
>>> On Thu, 2022-04-07 at 10:59 +0200, Christian König wrote:
>>>> Rework the internals of the dma_resv object to allow adding more
>>>> than
>>>> one
>>>> write fence and remember for each fence what purpose it had.
>>>>
>>>> This allows removing the workaround from amdgpu which used a
>>>> container
>>>> for
>>>> this instead.
>>>>
>>>> Signed-off-by: Christian König <christian.koenig@amd.com>
>>>> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
>>>> Cc: amd-gfx@lists.freedesktop.org
>>> afaict this change broke vmwgfx which now kernel oops right after
>>> boot.
>>> I haven't had the time to look into it yet, so I'm not sure what's
>>> the
>>> problem. I'll look at this tomorrow, but just in case you have some
>>> clues, the backtrace follows:
>> that's a known issue and should already be fixed with:
>>
>> commit d72dcbe9fce505228dae43bef9da8f2b707d1b3d
>> Author: Christian König <christian.koenig@amd.com>
>> Date:   Mon Apr 11 15:21:59 2022 +0200
> Unfortunately that doesn't seem to be it. The backtrace is from the
> current (as of the time of sending of this email) drm-misc-next, which
> has this change, so it's something else.

Ok, that's strange. In this case I need to investigate further.

Maybe VMWGFX is adding more than one fence and we actually need to 
reserve multiple slots.

Regards,
Christian.

>
> z