Messages in this thread | | | Date | Fri, 24 Jun 2022 14:43:16 +0200 | From | Michal Koutný <> | Subject | Re: [RFC PATCH] cpuset: Allow setscheduler regardless of manipulated task |
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On Thu, Jun 23, 2022 at 02:44:33PM -0400, Waiman Long <longman@redhat.com> wrote: > That could be an issue.
The way how I understand here is that the privileged process isn't part of contrained workload (if it were then, it can modify cpuset itself) like debugging or tracing a code within a container entered by the admin. The bypass could not be used to setscheduler (via migration) of an arbitrary process.
> What do you mean by nothing effectively changes?
It's a freshly created child (after cpuset_css_online()), so it inherits parent's attributes, so the migration from the parent to this child doesn't affect CPU affinity etc.
> Since the check is done on a taskset level, if only one of the tasks in the > taskset fails, the whole taskset fails. Maybe we should consider an option > for task based migration. So all the tasks that can be migrated will be > migrated and the rests will be left behind in the original cpuset.
Hm, I haven't thought about that. That might be in theory possible for threaded controllers (like cpuset) but I imagine it'd a bit messy, in particular for these implicit migrations upon controller enablement.
Thanks, Michal [unhandled content-type:application/pgp-signature] | |