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    SubjectRe: [tip:core/ipi] generic-ipi: eliminate spurious pointlessWARN_ON()s
    >>> Peter Zijlstra <> 13.03.09 09:54 >>>
    >Wouldn't leaving them in place but changing them to:
    >WARN_ON(irqs_disabled() && system_state == SYSTEM_RUNNING);
    >be clearer?

    I don't think that would be precise: system_state gets set to
    SYSTEM_RUNNING much later than APs get brought up (i.e. there are
    cases where the WARN_ON()s could validly trigger with SYSTEM_BOOTING),
    and also doesn't cover states > SYSTEM_RUNNING (where, again, after
    perhaps having brought down all APs the warnings could become pointless,
    but the warnings could be meaningful as long as there are still some APs

    While from an abstract code reading perspective your suggestion might
    seem reasonable, the changed placement really reflects what the warning
    is trying to warn about - a potential deadlock which cannot occur under
    the conditions filtered out by conditionals the warnings were moved


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