From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Tue, 5 Apr 2022 17:53:20 +0200 (CEST)
From: Richard Weinberger <richard@nod.at>
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Subject: Re: [PATCH] xnthread_relax: Make sure wakework irq work has a stack
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To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: Florian Bezdeka <florian.bezdeka@siemens.com>, xenomai <xenomai@xenomai.org>

----- Urspr=C3=BCngliche Mail -----
> Von: "Jan Kiszka" <jan.kiszka@siemens.com>
> I would like to have an explanation or prove points (traces, assertions)
> that we actually see xnthread_relax overtaking the delivery of its own
> wakework.

I can re-test with something like that:

diff --git a/kernel/cobalt/thread.c b/kernel/cobalt/thread.c
index beda67e18..4c100b645 100644
--- a/kernel/cobalt/thread.c
+++ b/kernel/cobalt/thread.c
@@ -2159,6 +2159,7 @@ void xnthread_relax(int notify, int reason)
        pipeline_clear_mayday();
=20
        trace_cobalt_shadow_relaxed(thread);
+       WARN_ON_ONCE(irq_work_is_busy(&wakework.inband_work.work));
 }
 EXPORT_SYMBOL_GPL(xnthread_relax);

But I fear this might take some time. The KASAM spat happened only once
and also only after the test ran for almost 5 days.

Thanks,
//richard