Initialize the irqfd waitqueue callback immediately prior to inserting the irqfd into the eventfd's waitqueue. Pre-initializing the state in a completely different context is all kinds of confusing, and incorrectly suggests that the waitqueue function needs to be initialize prior to vfs_poll().
Signed-off-by: Sean Christopherson seanjc@google.com --- virt/kvm/eventfd.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 42c02c35e542..8b9a87daa2bb 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -256,6 +256,13 @@ static void kvm_irqfd_register(struct file *file, wait_queue_head_t *wqh, struct kvm_irqfd_pt *p = container_of(pt, struct kvm_irqfd_pt, pt); struct kvm_kernel_irqfd *irqfd = p->irqfd;
+ /* + * Add the irqfd as a priority waiter on the eventfd, with a custom + * wake-up handler, so that KVM *and only KVM* is notified whenever the + * underlying eventfd is signaled. + */ + init_waitqueue_func_entry(&irqfd->wait, irqfd_wakeup); + add_wait_queue_priority(wqh, &irqfd->wait); }
@@ -395,12 +402,6 @@ kvm_irqfd_assign(struct kvm *kvm, struct kvm_irqfd *args) mutex_unlock(&kvm->irqfds.resampler_lock); }
- /* - * Install our own custom wake-up handling so we are notified via - * a callback whenever someone signals the underlying eventfd - */ - init_waitqueue_func_entry(&irqfd->wait, irqfd_wakeup); - /* * Set the irqfd routing and add it to KVM's list before registering * the irqfd with the eventfd, so that the routing information is valid