Re: [RFC] Are you good with Lockdep?

[Byungchul Park]

On Thu, Nov 12, 2020 at 02:56:49PM +0100, Daniel Vetter wrote:
> > > I think I understand it. For things like completions and other "wait for
> > > events" we have lockdep annotation, but it is rather awkward to implement.
> > > Having something that says "lockdep_wait_event()" and
> > > "lockdep_exec_event()" wrappers would be useful.
> >
> > Yes. It's a problem of lack of APIs. It can be done by reverting revert
> > of cross-release without big change. ;-)
> 
> +1 on lockdep-native support for this. For another use case I've added
> annotations for dma_fence_wait, and they're not entirely correct
> unfortunately. But the false positives is along the lines of "you

I'd like to help you solve the problem you are facing. Let me be back
and help you later. I have to all-stop what I'm doing at the moment
becasue of a very big personal issue, which is a sad thing.

Thank you,
Byungchul

> really shouldn't do this, even if it's in theory deadlock free". See
> 
> commit 5fbff813a4a328b730cb117027c43a4ae9d8b6c0
> Author: Daniel Vetter <daniel.vetter@xxxxxxxx>
> Date:   Tue Jul 7 22:12:05 2020 +0200
> 
>    dma-fence: basic lockdep annotations
> 
> for fairly lengthy discussion of the problem and what I ended up with.
> 
> Thanks, Daniel
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> http://blog.ffwll.ch