> From: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Sent: Wednesday, October 13, 2021 8:49 PM
>
> On Tue, Oct 12, 2021 at 08:57:22AM +0000, Liu, Yi L wrote:
> > > + ret = __vfio_group_get_from_iommu(iommu_group);
> > > + if (ret)
> > > + goto err_unlock;
> > >
> > > - minor = vfio_alloc_group_minor(group);
> > > - if (minor < 0) {
> > > - vfio_group_unlock_and_free(group);
> > > - return ERR_PTR(minor);
> > > + err = cdev_device_add(&group->cdev, &group->dev);
> > > + if (err) {
> > > + ret = ERR_PTR(err);
> > > + goto err_unlock;
> >
> > should this err branch put the vfio_group reference acquired
> > in above __vfio_group_get_from_iommu(iommu_group);?
>
> No, if ret was !NULL then the reference is returned to the caller via
> the err_unlock
>
> This path to cdev_device_add has ret = NULL so there is no reference
> to put back.
oh, yes. only if ret is NULL will go ahead to this place.
Thanks,
Yi Liu
