Re: [PATCH] pinctrl: bcm2835: Fix a few error paths

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Florian Fainelli <f.fainelli@gmail.com>
Cc: linux-kernel@vger.kernel.org,
	Linus Walleij <linus.walleij@linaro.org>,
	Ray Jui <rjui@broadcom.com>,
	Scott Branden <sbranden@broadcom.com>,
	"maintainer:BROADCOM BCM281XX/BCM11XXX/BCM216XX ARM ARCHITE..." 
	<bcm-kernel-feedback-list@broadcom.com>,
	Nicolas Saenz Julienne <nsaenz@kernel.org>,
	Phil Elwell <phil@raspberrypi.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>,
	Hans Verkuil <hverkuil-cisco@xs4all.nl>,
	Jason Wang <wangborong@cdjrlc.com>, Marc Zyngier <maz@kernel.org>,
	"open list:PIN CONTROL SUBSYSTEM" <linux-gpio@vger.kernel.org>,
	"moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE" 
	<linux-rpi-kernel@lists.infradead.org>,
	"moderated list:BROADCOM BCM2711/BCM2835 ARM ARCHITECTURE" 
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH] pinctrl: bcm2835: Fix a few error paths
Date: Fri, 28 Jan 2022 16:35:58 +0200	[thread overview]
Message-ID: <YfP/TuEERCrgst+k@smile.fi.intel.com> (raw)
In-Reply-To: <20220127215033.267227-1-f.fainelli@gmail.com>

On Thu, Jan 27, 2022 at 01:50:31PM -0800, Florian Fainelli wrote:
> After commit 266423e60ea1 ("pinctrl: bcm2835: Change init order for gpio
> hogs") a few error paths would not unwind properly the registration of
> gpio ranges. Correct that by assigning a single error label and goto it
> whenever we encounter a fatal error.

>  1 file changed, 15 insertions(+), 8 deletions(-)

While this seems legit per se, my eyes caught this:

>  	if (!girq->parents) {
> -		pinctrl_remove_gpio_range(pc->pctl_dev, &pc->gpio_range);
> -		return -ENOMEM;
> +		err = -ENOMEM;
> +		goto out_remove;

Non-devm....

>  	}
>  
>  	if (is_7211) {
>  		pc->wake_irq = devm_kcalloc(dev, BCM2835_NUM_IRQS,
>  					    sizeof(*pc->wake_irq),
>  					    GFP_KERNEL);

...followed by devm.

It means more ordering bugs in the ->remove() and error path are lurking
around. Can you double check and be sure that we do not have a case where
non-devm registration code followed by devm?

If that is the case it has to be fixed as well.

> -		if (!pc->wake_irq)
> -			return -ENOMEM;
> +		if (!pc->wake_irq) {
> +			err = -ENOMEM;
> +			goto out_remove;
> +		}
>  	}

-- 
With Best Regards,
Andy Shevchenko