Re: [PATCH v2] spmi: hisi-spmi-controller: manage the OF node reference in device initialization and cleanup

[Joe Hattori]

Thank you for your review.

On 12/19/24 04:49, Stephen Boyd wrote:
> Quoting Joe Hattori (2024-12-17 19:39:54)
> > spmi_controller_probe() increments the refcount of an OF node, but does
> > not release it. Instead, call of_node_get() in spmi_controller_alloc()
> > and release it in spmi_ctrl_release() to avoid the reference leak. Also
> > remove the lines in spmi_pmic_arb_bus_init() and spmi_controller_probe()
> > where a pdev's of_node is stored after spmi_controller_alloc() is
> > called.
>
> That last sentence says what is done but doesn't explain why. Please
> explain why stashing the of_node in the two drivers are removed.

Addressed in the v3 patch.

> > This bug was found by an experimental static analysis tool that I am
> > developing.
> >
> > Fixes: e562cf3aea3e ("spmi: hisi-spmi-controller: move driver from staging")
> > Signed-off-by: Joe Hattori <joe@xxxxxxxxxxxxxxxxxxxxx>
> [...]
> > diff --git a/drivers/spmi/spmi.c b/drivers/spmi/spmi.c
> > index fb0101da1485..e662a7a78df2 100644
> > --- a/drivers/spmi/spmi.c
> > +++ b/drivers/spmi/spmi.c
> > @@ -36,6 +36,7 @@ static void spmi_ctrl_release(struct device *dev)
> >          struct spmi_controller *ctrl = to_spmi_controller(dev);
> >   
> >          ida_free(&ctrl_ida, ctrl->nr);
> > +       of_node_put(dev->of_node);
> >          kfree(ctrl);
> >   }
> >   
> > @@ -458,7 +459,7 @@ struct spmi_controller *spmi_controller_alloc(struct device *parent,
> >          ctrl->dev.type = &spmi_ctrl_type;
> >          ctrl->dev.bus = &spmi_bus_type;
> >          ctrl->dev.parent = parent;
> > -       ctrl->dev.of_node = parent->of_node;
> > +       ctrl->dev.of_node = of_node_get(parent->of_node);
>
> Do we need to use device_set_node() here?

Yes, setting also the fwnode sounds cleaner. Applied in the v3 patch.

> >          spmi_controller_set_drvdata(ctrl, &ctrl[1]);

Best,
Joe