diff options
Diffstat (limited to 'drivers/s390')
| -rw-r--r-- | drivers/s390/crypto/vfio_ap_ops.c | 24 |
1 files changed, 5 insertions, 19 deletions
diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c index 7dc26365e29a..6e08d04b605d 100644 --- a/drivers/s390/crypto/vfio_ap_ops.c +++ b/drivers/s390/crypto/vfio_ap_ops.c @@ -1189,13 +1189,6 @@ static const struct attribute_group *vfio_ap_mdev_attr_groups[] = { * @matrix_mdev: a mediated matrix device * @kvm: reference to KVM instance * - * Note: The matrix_dev->lock must be taken prior to calling - * this function; however, the lock will be temporarily released while the - * guest's AP configuration is set to avoid a potential lockdep splat. - * The kvm->lock is taken to set the guest's AP configuration which, under - * certain circumstances, will result in a circular lock dependency if this is - * done under the @matrix_mdev->lock. - * * Return: 0 if no other mediated matrix device has a reference to @kvm; * otherwise, returns an -EPERM. */ @@ -1269,18 +1262,11 @@ static int vfio_ap_mdev_iommu_notifier(struct notifier_block *nb, * by @matrix_mdev. * * @matrix_mdev: a matrix mediated device - * @kvm: the pointer to the kvm structure being unset. - * - * Note: The matrix_dev->lock must be taken prior to calling - * this function; however, the lock will be temporarily released while the - * guest's AP configuration is cleared to avoid a potential lockdep splat. - * The kvm->lock is taken to clear the guest's AP configuration which, under - * certain circumstances, will result in a circular lock dependency if this is - * done under the @matrix_mdev->lock. */ -static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev, - struct kvm *kvm) +static void vfio_ap_mdev_unset_kvm(struct ap_matrix_mdev *matrix_mdev) { + struct kvm *kvm = matrix_mdev->kvm; + if (kvm && kvm->arch.crypto.crycbd) { down_write(&kvm->arch.crypto.pqap_hook_rwsem); kvm->arch.crypto.pqap_hook = NULL; @@ -1311,7 +1297,7 @@ static int vfio_ap_mdev_group_notifier(struct notifier_block *nb, matrix_mdev = container_of(nb, struct ap_matrix_mdev, group_notifier); if (!data) - vfio_ap_mdev_unset_kvm(matrix_mdev, matrix_mdev->kvm); + vfio_ap_mdev_unset_kvm(matrix_mdev); else if (vfio_ap_mdev_set_kvm(matrix_mdev, data)) notify_rc = NOTIFY_DONE; @@ -1448,7 +1434,7 @@ static void vfio_ap_mdev_close_device(struct vfio_device *vdev) &matrix_mdev->iommu_notifier); vfio_unregister_notifier(vdev->dev, VFIO_GROUP_NOTIFY, &matrix_mdev->group_notifier); - vfio_ap_mdev_unset_kvm(matrix_mdev, matrix_mdev->kvm); + vfio_ap_mdev_unset_kvm(matrix_mdev); } static int vfio_ap_mdev_get_device_info(unsigned long arg) |