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When it gets scheduled back in, and need_resched() is > not set, then the stale grant would be preserved, which is just wrong. > > RSEQ already keeps track of that and sets TIF_RSEQ, which invokes the > critical section and ID update mechanisms. > > Utilize them and clear the user space slice control member of struct rseq > unconditionally within the existing user access sections. That's just an > unconditional store more in that path. Reviewed-by: Mathieu Desnoyers -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com