Hello, Waiman. Sorry about the delay. Was off for a while. On Tue, Jul 27, 2021 at 05:14:27PM -0400, Waiman Long wrote: > However, if we have a complicated partition setup with multiple child > partitions. Invalid cpuset.cpus change in a parent partition will cause all > the child partitions to become invalid too. That is the scenario that I > don't want to happen inadvertently. Alternatively, we can restrict those I don't think there's anything fundamentally wrong with it given the requirement that userland has to monitor invalid state transitions. The same mass transition can happen through cpu hotplug operations, right? > invalid changes if a child partition exist and let it pass through and make > it invalid if it is a standalone partition. > > Please let me know which approach do you want me to take. I think it'd be best if we can stick to some principles rather than trying to adjust it for specific scenarios. e.g.: * If a given state can be reached through cpu hot [un]plug, any configuration attempt which reaches the same state should be allowed with the same end result as cpu hot [un]plug. * If a given state can't ever be reached in whichever way, the configuration attempting to reach such state should be rejected. Thanks. -- tejun