diff options
| -rw-r--r-- | virt/kvm/eventfd.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/virt/kvm/eventfd.c b/virt/kvm/eventfd.c index 30f70fd511c4..62e4cd947a90 100644 --- a/virt/kvm/eventfd.c +++ b/virt/kvm/eventfd.c @@ -166,7 +166,7 @@ irqfd_ptable_queue_proc(struct file *file, wait_queue_head_t *wqh, static int kvm_irqfd_assign(struct kvm *kvm, int fd, int gsi) { - struct _irqfd *irqfd; + struct _irqfd *irqfd, *tmp; struct file *file = NULL; struct eventfd_ctx *eventfd = NULL; int ret; @@ -203,9 +203,20 @@ kvm_irqfd_assign(struct kvm *kvm, int fd, int gsi) init_waitqueue_func_entry(&irqfd->wait, irqfd_wakeup); init_poll_funcptr(&irqfd->pt, irqfd_ptable_queue_proc); + spin_lock_irq(&kvm->irqfds.lock); + + ret = 0; + list_for_each_entry(tmp, &kvm->irqfds.items, list) { + if (irqfd->eventfd != tmp->eventfd) + continue; + /* This fd is used for another irq already. */ + ret = -EBUSY; + spin_unlock_irq(&kvm->irqfds.lock); + goto fail; + } + events = file->f_op->poll(file, &irqfd->pt); - spin_lock_irq(&kvm->irqfds.lock); list_add_tail(&irqfd->list, &kvm->irqfds.items); spin_unlock_irq(&kvm->irqfds.lock); |