diff options
| -rw-r--r-- | virt/kvm/irq_comm.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/virt/kvm/irq_comm.c b/virt/kvm/irq_comm.c index 59cf8dae006..fb861dd956f 100644 --- a/virt/kvm/irq_comm.c +++ b/virt/kvm/irq_comm.c @@ -159,7 +159,8 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level) * IOAPIC. So set the bit in both. The guest will ignore * writes to the unused one. */ - irq_rt = kvm->irq_routing; + rcu_read_lock(); + irq_rt = rcu_dereference(kvm->irq_routing); if (irq < irq_rt->nr_rt_entries) hlist_for_each_entry(e, n, &irq_rt->map[irq], link) { int r = e->set(e, kvm, irq_source_id, level); @@ -168,6 +169,7 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level) ret = r + ((ret < 0) ? 0 : ret); } + rcu_read_unlock(); return ret; } @@ -179,7 +181,10 @@ void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin) trace_kvm_ack_irq(irqchip, pin); - gsi = kvm->irq_routing->chip[irqchip][pin]; + rcu_read_lock(); + gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin]; + rcu_read_unlock(); + if (gsi != -1) hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link) @@ -279,9 +284,9 @@ void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask) void kvm_free_irq_routing(struct kvm *kvm) { - mutex_lock(&kvm->irq_lock); + /* Called only during vm destruction. Nobody can use the pointer + at this stage */ kfree(kvm->irq_routing); - mutex_unlock(&kvm->irq_lock); } static int setup_routing_entry(struct kvm_irq_routing_table *rt, @@ -387,8 +392,9 @@ int kvm_set_irq_routing(struct kvm *kvm, mutex_lock(&kvm->irq_lock); old = kvm->irq_routing; - kvm->irq_routing = new; + rcu_assign_pointer(kvm->irq_routing, new); mutex_unlock(&kvm->irq_lock); + synchronize_rcu(); new = old; r = 0; |