Re: [PATCH v2] watchdog: qcom: Propagate errors from optional IRQ lookup

> [Severity: High]
> Does this code leave wdt->wdd.info uninitialized if data->pretimeout is true
> but the optional IRQ is missing?
>
> If platform_get_irq_optional() returns -ENXIO, the if (irq > 0) branch is
> skipped. Since this all occurs inside the if (data->pretimeout) branch, the
> outer else block is bypassed.
>
> Could this cause devm_watchdog_register_device() to later fail with -EINVAL
> because wdd->info is NULL?
>
> >       } else {
> > -             if (irq == -EPROBE_DEFER)
> > -                     return -EPROBE_DEFER;
> > -
> >               wdt->wdd.info = &qcom_wdt_info;
> >       }
>
> --
> Sashiko AI review · https://sashiko.dev/#/patchset/[email protected]?part=1


Oh, it looks like this approach is correct.

Option C (default-then-override, only look up the IRQ when pretimeout
is supported):

----------------------
wdt->wdd.info = &qcom_wdt_info;

if (data->pretimeout) {
        irq = platform_get_irq_optional(pdev, 0);
        if(irq < 0 && irq != -ENXIO)
                return irq;

        if (irq > 0){
                ret = devm_request_irq(dev, irq, qcom_wdt_isr, 0,
                                                       "wdt_bark", &wdt->wdd);
                if(ret)
                        return ret;

                wdt->wdd.info= &qcom_wdt_pt_info;
                wdt->wdd.pretimeout = 1;
        }
}
-----------------------