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Date:   Tue, 1 Sep 2020 09:13:40 -0700
From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     peterz@infradead.org
Cc:     Lina Iyer <ilina@codeaurora.org>,
        Ulf Hansson <ulf.hansson@linaro.org>,
        Naresh Kamboju <naresh.kamboju@linaro.org>,
        "Rafael J. Wysocki" <rjw@rjwysocki.net>,
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        open list <linux-kernel@vger.kernel.org>,
        linux-mmc <linux-mmc@vger.kernel.org>,
        lkft-triage@lists.linaro.org, rcu@vger.kernel.org,
        Linux PM <linux-pm@vger.kernel.org>,
        Anders Roxell <anders.roxell@linaro.org>,
        Arnd Bergmann <arnd@arndb.de>,
        Rajendra Nayak <rnayak@codeaurora.org>,
        John Stultz <john.stultz@linaro.org>,
        Stephen Boyd <sboyd@kernel.org>,
        Lars Povlsen <lars.povlsen@microchip.com>,
        madhuparnabhowmik10@gmail.com,
        Viresh Kumar <viresh.kumar@linaro.org>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>
Subject: Re: WARNING: suspicious RCU usage - sdhci-pltfm: SDHCI platform and
 OF driver helper
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On Tue, Sep 01, 2020 at 05:50:14PM +0200, peterz@infradead.org wrote:
> On Tue, Sep 01, 2020 at 09:44:17AM -0600, Lina Iyer wrote:
> > > > > > > I could add RCU_NONIDLE for the calls to pm_runtime_put_sync_suspend()
> > > > > > > and pm_runtime_get_sync() in psci_enter_domain_idle_state(). Perhaps
> > > > > > > that's the easiest approach, at least to start with.
> 
> > I think this would be nice. This should also cover the case, where PM domain
> > power off notification callbacks call trace function internally. Right?
> 
> That's just more crap for me to clean up later :-(
> 
> trace_*_rcuidle() and RCU_NONIDLE() need to die, not proliferate.

Moving the idle-entry boundary further in is good in any number of ways.
But experience indicates that no matter how far you move it, there will
be something complex further in.  Unless you are pushing it all the way
into all the arch-specific code down as far as it can possibly go?

							Thanx, Paul