Hi Rafael,
On Fri, May 27, 2022 at 07:04:39PM +0200, Rafael J. Wysocki wrote:
> On Fri, May 27, 2022 at 11:02 AM Sakari Ailus
> <sakari.ailus@xxxxxxxxxxxxxxx> wrote:
> >
> > Hi Rafael,
> >
> > On Thu, May 26, 2022 at 09:19:17PM +0200, Rafael J. Wysocki wrote:
> > > > +static int acpi_tie_nondev_subnodes(struct acpi_device_data *data)
> > > > +{
> > > > + struct acpi_data_node *dn;
> > > > +
> > > > + list_for_each_entry(dn, &data->subnodes, sibling) {
> > > > + acpi_status status;
> > > > + int ret;
> > > > +
> > > > + status = acpi_attach_data(dn->handle, acpi_nondev_subnode_tag, dn);
> > > > + if (ACPI_FAILURE(status)) {
> > > > + acpi_handle_err(dn->handle, "Can't tag data node\n");
> > > > + return 0;
> > > > + }
> > > > +
> > > > + ret = acpi_tie_nondev_subnodes(&dn->data);
> > > > + if (ret)
> > > > + return ret;
> > >
> > > Is it actually possible that this returns anything different from 0?
> >
> > acpi_attach_data() involves allocating memory and resolving a reference.
> > Both can fail.
>
> Yes, they can, but the value returned by acpi_attach_data() is
> effectively ignored above (except for printing the error message,
> which BTW could be "info" and provide more information).
Oops. Good point.
I intended this to return an error here. I don't have strong opinion on
which way to go though. How about changing that to -ENOMEM?
I think this is basically a decision on whether any subnodes could be
referenced if ore or more of them could not. I don't expect this to happen
in practice.
>
> I don't see how acpi_tie_nondev_subnodes() can produce a nonzero return value.
--
Kind regards,
Sakari Ailus
