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Do we need both > fixes (if that is allowed) or maybe we need to split this change in two > (as this second part won't apply to old kernels w/o dl-servers)? Good point. I will split it in two in the next version: - __dl_sub() and __dl_add() skip the division when the root domain has no active CPU. Fixes: daec57983670. This alone removes the divide error, on the debugfs path too. - The debugfs write is refused while the runqueue is offline. Fixes: 4043f5498416, which it completes for the hotplug windows. It only applies where that commit is. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com