Re: Lockdep spalt on killing a processes

[Andrey Grodzovsky <andrey.grodzovsky@amd.com>]

On 2021-10-27 10:34 a.m., Christian König wrote:
> Am 27.10.21 um 16:27 schrieb Andrey Grodzovsky:
>> [SNIP]
>>>
>>>> Let me please know if I am still missing some point of yours.
>>>
>>> Well, I mean we need to be able to handle this for all drivers.
>>
>>
>> For sure, but as i said above in my opinion we need to change only 
>> for those drivers that don't use the _locked version.
>
> And that absolutely won't work.
>
> See the dma_fence is a contract between drivers, so you need the same 
> calling convention between all drivers.
>
> Either we always call the callback with the lock held or we always 
> call it without the lock, but sometimes like that and sometimes 
> otherwise won't work.
>
> Christian.


I am not sure I fully understand what problems this will cause but 
anyway, then we are back to irq_work. We cannot embed irq_work as union 
within dma_fenc's cb_list
because it's already reused as timestamp and as rcu head after the fence 
is signaled. So I will do it within drm_scheduler with single irq_work 
per drm_sched_entity
as we discussed before.

Andrey


>
>>
>> Andrey
>