Re: [PATCH v26 00/10] Simple Donor Migration for Proxy Execution

[John Stultz]

On Thu, Apr 2, 2026 at 11:31 AM John Stultz <jstultz@xxxxxxxxxx> wrote:
> On Thu, Apr 2, 2026 at 8:51 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> >
> > So, I've not gone through all the cases yet, and it is *COMPLETELY*
> > untested, but something like the below perhaps?
> >
> But I'll give this a shot (and will integrate your ttwu_runnable
> cleanups regardless) and see how it does.

So I tweaked it to move the blocked_on handling after the
p->se.sched_delayed check in ttwu_runnable(), otherwise it crashed
very quickly.

But even then, I unfortunately quickly see the WARN_ON_ONCE(state ==
TASK_RUNNING); in proxy_deactivate() trip and then it hangs after
starting the mutex_lock-torture tests. :(

I'll try to get my next set cleaned up and shared here shortly and
maybe we can try to whittle it down to something closer to your
approach.

thanks
-john