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That write is refused in v3 while the CPU is inactive (patch 4). The inactive timer path is closed by patches 10 and 14: a release after a rebuild takes nothing, and otherwise comes from the root domain that counted the bandwidth. With admission control off, sched_setattr() on a task asleep on an offline CPU still counts in the default root domain, with no active CPU to spread the change over; the guard is for that, and the record releases from the same root domain. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com