diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 8cf6a6fef79658..583cc29080764e 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -4595,11 +4595,15 @@ void rcutree_migrate_callbacks(int cpu) struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); bool needwake; - if (rcu_rdp_is_offloaded(rdp) || - rcu_segcblist_empty(&rdp->cblist)) - return; /* No callbacks to migrate. */ + if (rcu_rdp_is_offloaded(rdp)) + return; raw_spin_lock_irqsave(&rcu_state.barrier_lock, flags); + if (rcu_segcblist_empty(&rdp->cblist)) { + raw_spin_unlock_irqrestore(&rcu_state.barrier_lock, flags); + return; /* No callbacks to migrate. */ + } + WARN_ON_ONCE(rcu_rdp_cpu_online(rdp)); rcu_barrier_entrain(rdp); my_rdp = this_cpu_ptr(&rcu_data);