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From:   "Rafael J. Wysocki" <rjw@rjwysocki.net>
To:     Anson Huang <anson.huang@nxp.com>
Cc:     Viresh Kumar <viresh.kumar@linaro.org>,
        Jacky Bai <ping.bai@nxp.com>,
        "linux-pm@vger.kernel.org" <linux-pm@vger.kernel.org>
Subject: Re: About CPU hot-plug stress test failed in cpufreq driver
Date:   Fri, 29 Nov 2019 12:39:30 +0100
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On Monday, November 25, 2019 1:44:20 PM CET Rafael J. Wysocki wrote:
> On Mon, Nov 25, 2019 at 7:05 AM Anson Huang <anson.huang@nxp.com> wrote:
> >
> > Hi, Rafael
> >         Looks like adding pr_info() in irq_work_sync() makes issue can NOT be reproduced, any possibility of race happen there and the pr_info eliminate the race condition? I will continue run the test with the pr_info to see if any luck to reproduce it.
> 
> Yes, it looks like there is a race condition in there.
> 
> I need to analyze the code a bit to confirm it which may take a bit of time.

I'm not seeing any races in there expect for the possible over-optimization
of irq_work_sync() that I was talking about before.

Cheers!