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Date:   Wed, 16 Mar 2022 17:18:40 +0100
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Steven Rostedt <rostedt@goodmis.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: sched_core_balance() releasing interrupts with pi_lock held
Message-ID: <YjIN4C8EFIOOR+o4@linutronix.de>
References: <20220308161455.036e9933@gandalf.local.home>
 <20220315174606.02959816@gandalf.local.home>
 <YjIKQBIbJR/kRR+N@linutronix.de>
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On 2022-03-16 17:03:14 [+0100], To Steven Rostedt wrote:
=E2=80=A6
> which looked right but RT still fall apart:
=E2=80=A6
> | =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> | WARNING: bad unlock balance detected!
> | 5.17.0-rc8-rt14+ #10 Not tainted
> | -------------------------------------
=E2=80=A6
=E2=80=A6
> It is always the local-lock that is breaks apart. Based on "locks held"
> and the lock it tries to release it looks like the lock was acquired on
> CPU-A and released on CPU-B.

with

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 33ce5cd113d8..f4675bd8f878 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5968,6 +5967,9 @@ static bool try_steal_cookie(int this, int that)
 		if (p =3D=3D src->core_pick || p =3D=3D src->curr)
 			goto next;
=20
+		if (p->migration_disabled)
+			goto next;
+
 		if (!cpumask_test_cpu(this, &p->cpus_mask))
 			goto next;
=20
on top my problems are gone. Let me do some testing and then I would
patch unless PeterZ does the yelling :)

> > Thanks,
> >=20
> > -- Steve
>=20
Sebastian