Re: [RESEND PATCH v6 14/14] iommu/rockchip: Support sharing IOMMU between masters

[JeffyChen]

Hi Robin,

On 03/01/2018 07:03 PM, Robin Murphy wrote:
> > +static struct iommu_group *rk_iommu_device_group(struct device *dev)
> > +{
> > +    struct rk_iommu *iommu;
> > +
> > +    iommu = rk_iommu_from_dev(dev);
> > +
> > +    return iommu->group;
>
> Oops, seems I overlooked this in my previous review - it should really be:
>
>      return iommu_group_get(iommu->group);
>
> or the refcounting will be unbalanced on those future systems where it
> really will be called more than once.
hmmm, right, it should be return iommu_group_ref_get(iommu->group);

i was following omap iommu:
static struct iommu_group *omap_iommu_device_group(struct device *dev)
{
        struct omap_iommu_arch_data *arch_data = dev->archdata.iommu;
        struct iommu_group *group = ERR_PTR(-EINVAL);

        if (arch_data->iommu_dev)
                group = arch_data->iommu_dev->group;

        return group;
}

will fix it too in the version.

> Robin.