On Mon, Jan 16, 2023 at 08:56:25PM -0800, Jakub Kicinski wrote:
> On Sat, 14 Jan 2023 12:39:09 -0800 Ajit Khaparde wrote:
> > > > +static void bnxt_aux_dev_release(struct device *dev)
> > > > +{
> > > > + struct bnxt_aux_dev *bnxt_adev =
> > > > + container_of(dev, struct bnxt_aux_dev, aux_dev.dev);
> > > > + struct bnxt *bp = netdev_priv(bnxt_adev->edev->net);
> > > > +
> > > > + bnxt_adev->edev->en_ops = NULL;
> > > > + kfree(bnxt_adev->edev);
> > >
> > > And yet the reference counted "release" function accesses the bp->adev
> > > like it must exist.
> > >
> > > This seems odd to me - why do we need refcounting on devices at all
> > > if we can free them synchronously? To be clear - I'm not sure this is
> > > wrong, just seems odd.
> > I followed the existing implementations in that regard. Thanks
>
> Leon, could you take a look? Is there no problem in assuming bnxt_adev
> is still around in the release function?
You caught a real bug. The auxdev idea is very simple - it needs to
behave like driver core, but in the driver itself.
As such, bnxt_aux_dev_free() shouldn't be called after bnxt_rdma_aux_device_uninit().
Device will be released through auxiliary_device_uninit();
BTW, line 325 from below shouldn't exist too.
312 void bnxt_rdma_aux_device_uninit(struct bnxt *bp)
313 {
...
325 if (bnxt_adev->id >= 0)
326 ida_free(&bnxt_aux_dev_ids, bnxt_adev->id);
And one line bnxt_aux_dev_alloc() needs to be deleted too.
Thanks
