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Let me go revert that. > > This seems to work? Great! Makes sense to me, I re-ran all my stress tests and everything looks good on my side. FWIW, Tested-by: Andrea Righi arighi@nvidia.com Can we route this through your branch / want me to send a new patch? Thanks! -Andrea > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index 80c9559a3e30..aa3da4d3b8e3 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -1036,6 +1036,12 @@ static void update_dl_entity(struct sched_dl_entity *dl_se) > return; > } > > + /* > + * When [4] D->A is followed by [1] A->B, dl_defer_running > + * needs to be cleared, otherwise it will fail to properly > + * start the zero-laxity timer. > + */ > + dl_se->dl_defer_running = 0; > replenish_dl_new_period(dl_se, rq); > } else if (dl_server(dl_se) && dl_se->dl_defer) { > /* > @@ -1654,6 +1660,12 @@ void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec) > * dl_server_active = 1; > * enqueue_dl_entity() > * update_dl_entity(WAKEUP) > + * if (dl_time_before() || dl_entity_overflow) > + * dl_defer_running = 0; > + * replenish_dl_new_period(); > + * // fwd period > + * dl_throttled = 1; > + * dl_defer_armed = 1; > * if (!dl_defer_running) > * dl_defer_armed = 1; > * dl_throttled = 1;