Re: [bug report] iio: adc: add a driver for Qualcomm PM8xxx HK/XOADC

From: Linus Walleij <linus.walleij@linaro.org>
To: Dan Carpenter <error27@gmail.com>
Cc: linux-iio@vger.kernel.org
Subject: Re: [bug report] iio: adc: add a driver for Qualcomm PM8xxx HK/XOADC
Date: Thu, 23 Mar 2023 09:11:37 +0100	[thread overview]
Message-ID: <CACRpkdaiFkgEmbfUHmmr8J6afcr-W4ngtcVUwbAZn+KsumG+pg@mail.gmail.com> (raw)
In-Reply-To: <02034937-12e2-44f5-8311-10d960dc7dc4@kili.mountain>

On Wed, Mar 22, 2023 at 10:09 AM Dan Carpenter <error27@gmail.com> wrote:

> [ No idea why this warning is showing up after 6 years. -dan ]

:D

> This is a semi-automatic email about new static checker warnings.
>
> The patch 63c3ecd946d4: "iio: adc: add a driver for Qualcomm PM8xxx
> HK/XOADC" from Apr 4, 2017, leads to the following Smatch complaint:
>
>     drivers/iio/adc/qcom-pm8xxx-xoadc.c:769 pm8xxx_xoadc_parse_channel()
>     error: we previously assumed 'hwchan' could be null (see line 761)
>
> drivers/iio/adc/qcom-pm8xxx-xoadc.c
>    760          hwchan = &hw_channels[0];
>
> Here the hw_channels is variant->channels so it potentially is NULL
> (maybe?  I don't know the context very well).
>
>    761          while (hwchan && hwchan->datasheet_name) {
>                        ^^^^^^
> Check for NULL.

Actually there was a patch for this last week:
https://lore.kernel.org/linux-iio/20230314193709.15208-1-xhxgldhlpfy@gmail.com/

It seems the other static checker also found it now...

Yours,
Linus Walleij