Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

[deliverable/linux.git] / virt / kvm / kvm_main.c

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index cc081ccfcaa3743ca5e0f46dd350bda36bc3ec72..195078225aa5d0c3b3214fd40e0b5f441c5d7518 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -696,6 +696,11 @@ static void kvm_destroy_devices(struct kvm *kvm)
 {
        struct kvm_device *dev, *tmp;
 
+       /*
+        * We do not need to take the kvm->lock here, because nobody else
+        * has a reference to the struct kvm at this point and therefore
+        * cannot access the devices list anyhow.
+        */
        list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
                list_del(&dev->vm_node);
                dev->ops->destroy(dev);
@@ -2832,19 +2837,28 @@ static int kvm_ioctl_create_device(struct kvm *kvm,
        dev->ops = ops;
        dev->kvm = kvm;
 
+       mutex_lock(&kvm->lock);
        ret = ops->create(dev, cd->type);
        if (ret < 0) {
+               mutex_unlock(&kvm->lock);
                kfree(dev);
                return ret;
        }
+       list_add(&dev->vm_node, &kvm->devices);
+       mutex_unlock(&kvm->lock);
+
+       if (ops->init)
+               ops->init(dev);
 
        ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
        if (ret < 0) {
                ops->destroy(dev);
+               mutex_lock(&kvm->lock);
+               list_del(&dev->vm_node);
+               mutex_unlock(&kvm->lock);
                return ret;
        }
 
-       list_add(&dev->vm_node, &kvm->devices);
        kvm_get_kvm(kvm);
        cd->fd = ret;
        return 0;