Re: [PATCH RT v2] Fix a lockup in wait_for_completion() and friends

[Corey Minyard]

On Tue, Jul 02, 2019 at 10:35:36AM +0200, Sebastian Andrzej Siewior wrote:
> On 2019-07-02 09:04:18 [+0200], Kurt Kanzenbach wrote:
> > > In fact, my system doesn't boot with this commit in 5.0-rt.
> > >
> > > If I revert 90e1b18eba2ae4a729 ("swait: Delete the task from after a
> > > wakeup occured") the machine boots again.
> > >
> > > Sebastian, I think that's a bad commit, please revert it.
> > 
> > I'm having the same problem on a Cyclone V based ARM board. Reverting
> > this commit solves the boot issue for me as well.
> 
> Okay. So the original Corey fix as in v5.0.14-rt9 works for everyone.
> Peter's version as I picked it up for v5.0.21-rt14 is causing problems
> for two persons now.
> 
> I'm leaning towards reverting it back to old version for nowâ

Just to avoid confusion... it wasn't my patch 1921ea799b7dc56
(sched/completion: Fix a lockup in wait_for_completion()) that caused
the issue, nor was it Peter's version of it.  Instead, it was the patch
mentioned above, 90e1b18eba2ae4a729 ("swait: Delete the task from after a
wakeup occured"), which came from someone else.  I can verify by visual
inspection that that patch is broken and it should definitely be removed.
Just don't want someone to be confused and remove the wrong patch.

-corey


> 
> > Thanks,
> > Kurt
> 
> Sebastian