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Date:   Thu, 19 May 2022 15:19:26 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Jing-Ting Wu <jing-ting.wu@mediatek.com>
Cc:     Daniel Bristot de Oliveira <bristot@redhat.com>,
        Valentin Schneider <vschneid@redhat.com>, tglx@linutronix.de,
        wsd_upstream@mediatek.com, linux-kernel@vger.kernel.org,
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        linux-mediatek@lists.infradead.org, Jonathan.JMChen@mediatek.com,
        "chris.redpath@arm.com" <chris.redpath@arm.com>,
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        Ingo Molnar <mingo@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Christian Brauner <brauner@kernel.org>
Subject: Re: [Bug] Race condition between CPU hotplug off flow and
 __sched_setscheduler()
Message-ID: <20220519131926.GB6479@worktop.programming.kicks-ass.net>
References: <4a0aa13c99ffd6aea6426f83314aa2a91bc8933f.camel@mediatek.com>
 <20220519131452.GG2578@worktop.programming.kicks-ass.net>
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On Thu, May 19, 2022 at 03:14:52PM +0200, Peter Zijlstra wrote:
> On Thu, May 19, 2022 at 08:53:15PM +0800, Jing-Ting Wu wrote:
> > Hi all
> > 
> > 
> > There is a race condition between CPU hotplug off flow and
> > __sched_setscheduler(), which will cause hang-up in CPU hotplug off
> > flow.
> 
> Oooh, you're using core scheduling and the A/B are SMT siblings?

Hmm, no.. lemme try again.