Re: [PATCH] thermal/drivers/rcar: add error checking in probe()

On Tue, Jun 23, 2026 at 10:18:22AM +0200, Niklas Söderlund wrote:
> Hi Dan,
> 
> Thanks for your work.
> 
> On 2026-06-23 10:49:29 +0300, Dan Carpenter wrote:
> > The thermal_zone_device_register_with_trips() can fail for a number of
> > reasons, including allocation failures.  Check for error pointers to
> > avoid an error pointer dereference.
> > 
> > Fixes: 9d617949d490 ("thermal/drivers/renesas: Group all renesas thermal drivers together")
> 
> I don't think this is correct as this commits just moves the file.
> 
> > Signed-off-by: Dan Carpenter <[email protected]>
> > ---
> >  drivers/thermal/renesas/rcar_thermal.c | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/drivers/thermal/renesas/rcar_thermal.c b/drivers/thermal/renesas/rcar_thermal.c
> > index 6e5dcac5d47a..71f836fbc698 100644
> > --- a/drivers/thermal/renesas/rcar_thermal.c
> > +++ b/drivers/thermal/renesas/rcar_thermal.c
> > @@ -492,6 +492,11 @@ static int rcar_thermal_probe(struct platform_device *pdev)
> >  				"rcar_thermal", trips, ARRAY_SIZE(trips), priv,
> >  						&rcar_thermal_zone_ops, NULL, 0,
> >  						idle);
> > +			if (IS_ERR(priv->zone)) {
> > +				ret = PTR_ERR(priv->zone);
> > +				priv->zone = NULL;
> > +				goto error_unregister;
> > +			}
> 
> While this indeed is an issue that should be fixed I don't think this is 
> the correct fix. Below the if .. else .. block where this is added there 
> already is a check for IS_ERR(priv->zone). That however does not guard 
> against the usage of priv->zone for thermal_zone_device_enable().
> 
> We should only call thermal_zone_device_enable() if we are on a system 
> that uses OF (gated by chip->use_of_thermal) which is the reason for the 
> if .. else .. block in the first place.

Uh, what?  Other way around.  Only when use_of_thermal is false.
This function is weirdly confusing...  Also the rcar_thermal_remove()
function already calls thermal_zone_device_unregister().  I'll send a
v2 later.

regards,
dan carpenter