[Intel-gfx] [PATCH v5 09/10] vfio/pci: Extend VFIO_DEVICE_GET_PCI_HOT_RESET_INFO for vfio device cdev

[Liu, Yi L]

> From: Liu, Yi L <yi.l.liu at intel.com>
> Sent: Thursday, May 18, 2023 9:22 PM
> 
> > From: Alex Williamson <alex.williamson at redhat.com>
> > Sent: Thursday, May 18, 2023 6:02 AM
> >
> > On Sat, 13 May 2023 06:21:35 -0700
> > Yi Liu <yi.l.liu at intel.com> wrote:

> >
> > static int vfio_hot_reset_devid(struct vfio_device *vdev,
> >                                 struct iommufd_ctx *iommufd_ctx)
> > {
> >         struct iommu_group *group;
> >         int devid;
> >
> >         if (!vdev)
> >                 return VFIO_PCI_DEVID_NOT_OWNED;
> >
> >         if (vfio_iommufd_physical_ictx(vdev) == iommufd_ctx)
> >                 return vfio_iommufd_physical_devid(vdev);

Do we need to check the return of this helper? It returns -EINVAL
when iommufd_access and iommufd_device are both null. Though
not possible in this path. Is a WARN_ON needed or not?

Regards,
Yi Liu

> >
> >         group = iommu_group_get(vdev->dev);
> >         if (!group)
> >                 return VFIO_PCI_DEVID_NOT_OWNED;
> >
> >         if (iommufd_ctx_has_group(iommufd_ctx, group))
> >                 devid = VFIO_PCI_DEVID_OWNED;
> >
> >         iommu_group_put(group);
> >
> >         return devid;
> > }