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Date:   Wed, 20 Jan 2021 18:45:16 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     vincent.donnefort@arm.com
Cc:     tglx@linutronix.de, linux-kernel@vger.kernel.org,
        valentin.schneider@arm.com
Subject: Re: [PATCH 3/4] cpu/hotplug: Add cpuhp_invoke_callback_range()
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 <1610385047-92151-4-git-send-email-vincent.donnefort@arm.com>
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On Mon, Jan 11, 2021 at 05:10:46PM +0000, vincent.donnefort@arm.com wrote:
> @@ -475,6 +478,11 @@ cpuhp_set_state(struct cpuhp_cpu_state *st, enum cpuhp_state target)
>  static inline void
>  cpuhp_reset_state(struct cpuhp_cpu_state *st, enum cpuhp_state prev_state)
>  {
> +	st->target = prev_state;
> +
> +	if (st->rollback)
> +		return;

I'm thinking that if we call rollback while already rollback we're hosed
something fierce, no?

That like going up, failing, going back down again, also failing, giving
up in a fiery death.