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Date:   Mon, 26 Sep 2022 15:37:41 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Christian Borntraeger <borntraeger@linux.ibm.com>
Cc:     bigeasy@linutronix.de, dietmar.eggemann@arm.com,
        ebiederm@xmission.com, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org, mgorman@suse.de, mingo@kernel.org,
        oleg@redhat.com, rjw@rjwysocki.net, rostedt@goodmis.org,
        tj@kernel.org, vincent.guittot@linaro.org, will@kernel.org,
        Marc Hartmayer <mhartmay@linux.ibm.com>,
        Amit Shah <amit@kernel.org>,
        "virtualization@lists.linux-foundation.org" 
        <virtualization@lists.linux-foundation.org>
Subject: Re: [PATCH v3 6/6] freezer,sched: Rewrite core freezer logic
Message-ID: <YzGrJSLXpocpGIha@hirez.programming.kicks-ass.net>
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On Mon, Sep 26, 2022 at 03:23:10PM +0200, Christian Borntraeger wrote:
> Am 26.09.22 um 14:55 schrieb Peter Zijlstra:
> 
> > Could you please test with something like the below on? I can boot that
> > with KVM, but obviously I didn't suffer any weirdness to begin with :/
> > 
> > ---
> > diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> > index 4e6a6417211f..ef9ccfc3a8c0 100644
> > --- a/kernel/sched/core.c
> > +++ b/kernel/sched/core.c
> > @@ -4051,6 +4051,8 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
> >   	unsigned long flags;
> >   	int cpu, success = 0;
> > +	WARN_ON_ONCE(state & TASK_FREEZABLE);
> > +
> >   	preempt_disable();
> >   	if (p == current) {
> >   		/*
> 
> Does not seem to trigger.

Moo -- quite the puzzle this :/ I'll go stare at it more then.