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From:   Chris Bainbridge <chris.bainbridge@gmail.com>
Date:   Thu, 8 Jun 2023 10:41:51 +0100
Message-ID: <CAP-bSRZa9axG59E3knkVXy4=36irR9E7SXqT-QSikW7BoQueBw@mail.gmail.com>
Subject: Re: PROBLEM: skew message does not handle negative ns skew
To:     paulmck@kernel.org
Cc:     Feng Tang <feng.tang@intel.com>, tglx@linutronix.de,
        sboyd@kernel.org, LKML <linux-kernel@vger.kernel.org>
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On Wed, 7 Jun 2023 at 20:04, Paul E. McKenney <paulmck@kernel.org> wrote:
>
> That is a bit user-unfriendly.  Does the following fix address this
> issue at your end?

[    2.095149] clocksource: timekeeping watchdog on CPU3: Marking
clocksource 'tsc' as unstable because the skew is too large:
[    2.095152] clocksource:                       'hpet' wd_nsec:
515998611 wd_now: 1c29fb9 wd_last: 151e3b8 mask: ffffffff
[    2.095154] clocksource:                       'tsc' cs_nsec:
515124524 cs_now: 8af4c89f9 cs_last: 874f8e80b mask: ffffffffffffffff
[    2.095155] clocksource:                       Clocksource 'tsc'
skewed -874087 ns (0 ms) over watchdog 'hpet' interval of 515998611 ns
(515 ms)