On Thu, Oct 17, 2024 at 03:52:30PM -0300, Jason Gunthorpe wrote: > > + if (viommu->ops && viommu->ops->vdevice_alloc) > > + vdev = viommu->ops->vdevice_alloc(viommu, idev->dev, virt_id); > > + else > > + vdev = __iommufd_vdevice_alloc(ucmd->ictx, sizeof(*vdev)); > > + if (IS_ERR(vdev)) { > > + rc = PTR_ERR(vdev); > > + goto out_unlock_igroup; > > + } > > + > > + vdev->idev = idev; > > + vdev->id = virt_id; > > + vdev->viommu = viommu; > > + > > + idev->vdev = vdev; > > + refcount_inc(&idev->obj.users); > > + refcount_inc(&viommu->obj.users); > > + > > + curr = xa_cmpxchg(&viommu->vdevs, virt_id, NULL, vdev, GFP_KERNEL); > > + if (curr) { > > + rc = xa_err(curr) ? : -EBUSY; > > + goto out_abort; > > + } > > + > > + cmd->out_vdevice_id = vdev->obj.id; > > + rc = iommufd_ucmd_respond(ucmd, sizeof(*cmd)); > > + if (rc) > > + goto out_abort; > > + iommufd_object_finalize(ucmd->ictx, &vdev->obj); > > + goto out_unlock_igroup; > > + > > +out_abort: > > + iommufd_object_abort_and_destroy(ucmd->ictx, &vdev->obj); > > But be mindful of this abort, it doesn't want to be inside the lock if > it also gets the lock.. fail_nth should be updated to cover these new > ioctls to look for tricky things like that I added an abort() beside destroy(): +void iommufd_vdevice_abort(struct iommufd_object *obj) +{ + struct iommufd_vdevice *old, *vdev = + container_of(obj, struct iommufd_vdevice, obj); + struct iommufd_viommu *viommu = vdev->viommu; + struct iommufd_device *idev = vdev->idev; + + lockdep_assert_not_held(&idev->igroup->lock); + + if (viommu->ops && viommu->ops->vdevice_free) + viommu->ops->vdevice_free(vdev); + + old = xa_cmpxchg(&viommu->vdevs, vdev->id, vdev, NULL, GFP_KERNEL); + if (old) + WARN_ON(old != vdev); + + refcount_dec(&viommu->obj.users); + refcount_dec(&idev->obj.users); + idev->vdev = NULL; +} + +void iommufd_vdevice_destroy(struct iommufd_object *obj) +{ + struct iommufd_vdevice *vdev = + container_of(obj, struct iommufd_vdevice, obj); + + mutex_lock(&vdev->idev->igroup->lock); + iommufd_vdevice_abort(obj); + mutex_unlock(&vdev->idev->igroup->lock); +} ---------------------------------------------------------- And I added fail_nth coverage for IOMMU_VIOMMU/VDEVICE_ALLOC cmds. Thanks Nicolin