> From: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Sent: Tuesday, March 16, 2021 9:34 PM
>
> On Tue, Mar 16, 2021 at 07:55:11AM +0000, Tian, Kevin wrote:
>
> > > +void *vfio_del_group_dev(struct device *dev)
> > > +{
> > > + struct vfio_device *device = dev_get_drvdata(dev);
> > > + void *device_data = device->device_data;
> > > +
> > > + vfio_unregister_group_dev(device);
> > > dev_set_drvdata(dev, NULL);
> >
> > Move to vfio_unregister_group_dev? In the cover letter you mentioned
> > that drvdata is managed by the driver but removed from the core.
>
> "removed from the core" means the core code doesn't touch drvdata at
> all.
>
> > Looks it's also the rule obeyed by the following patches.
>
> The dev_set_drvdata(NULL) on remove is mostly cargo-cult nonsense. The
> driver core sets it to null immediately after the remove function
> returns, so to add another set needs a very strong reason.
>
> It is only left here temporarily, the last patch deletes it.
>
Ah, I didn't realize dev_set_drvdata(NULL) is nonsense here. Just saw
no place clears it after this series.
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
