Date:   Mon, 30 Jan 2023 11:04:07 +0100
From:   Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To:     Ulf Hansson <ulf.hansson@linaro.org>
Cc:     Sudeep Holla <sudeep.holla@arm.com>,
        Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Lorenzo Pieralisi <lpieralisi@kernel.org>,
        linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        Adrien Thierry <athierry@redhat.com>,
        Brian Masney <bmasney@redhat.com>,
        linux-rt-users@vger.kernel.org
Subject: Re: [PATCH v3] cpuidle: psci: Do not suspend topology CPUs on
 PREEMPT_RT
Message-ID: <Y9eWF1wZe0p6Gzmq@linutronix.de>
References: <20230119184228.683892-1-krzysztof.kozlowski@linaro.org>
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 <c247710b-369a-67d0-0637-b32192d25e4d@linaro.org>
 <CAPDyKFrS6OER2h3XmHMfbjBA09HT8LYN9A90TPjd0RPim3jMaw@mail.gmail.com>
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On 2023-01-25 11:08:04 [+0100], Ulf Hansson wrote:
> > It's the power domain sued for other devices, so we need it. Otherwise
> > other devices will keep waiting for this missing power domain provider.
> 
Ach this explains my other question I had.
> 
> And we are still able to use those idle states that are solely per
> CPU, which is probably nice to have. No?

If the entry/ exit latency is not known, it can be dangerous.

> Kind regards
> Uffe

Sebastian