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This seems a bit fragile to me to assume that if rdp_gp->nocb_gp_kthread then rdp->nocb_cb_kthread is valid. Or is there a path that makes sure this invariant is always satisfied? If so, can we add additional warnings for checking this invariant? Also from the other thread, it sounds like there is more work to do here (related patches so I'd like to defer this to 6.17 - feel free to keep posting patches for this work though). Thanks! - Joel > --- > kernel/rcu/tree_nocb.h | 5 ++--- > 1 file changed, 2 insertions(+), 3 deletions(-) > > diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h > index 1596812f7f12..6679140bb0b5 100644 > --- a/kernel/rcu/tree_nocb.h > +++ b/kernel/rcu/tree_nocb.h > @@ -1146,7 +1146,6 @@ static bool rcu_nocb_rdp_offload_wait_cond(struct rcu_data *rdp) > static int rcu_nocb_rdp_offload(struct rcu_data *rdp) > { > int wake_gp; > - struct rcu_data *rdp_gp = rdp->nocb_gp_rdp; > > WARN_ON_ONCE(cpu_online(rdp->cpu)); > /* > @@ -1156,7 +1155,7 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) > if (!rdp->nocb_gp_rdp) > return -EINVAL; > > - if (WARN_ON_ONCE(!rdp_gp->nocb_gp_kthread)) > + if (WARN_ON_ONCE(!rdp->nocb_gp_kthread)) > return -EINVAL; > > pr_info("Offloading %d\n", rdp->cpu); > @@ -1166,7 +1165,7 @@ static int rcu_nocb_rdp_offload(struct rcu_data *rdp) > > wake_gp = rcu_nocb_queue_toggle_rdp(rdp); > if (wake_gp) > - wake_up_process(rdp_gp->nocb_gp_kthread); > + wake_up_process(rdp->nocb_gp_kthread); > > swait_event_exclusive(rdp->nocb_state_wq, > rcu_nocb_rdp_offload_wait_cond(rdp));