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Date:   Wed, 19 Jul 2023 19:54:22 +0300
From:   Andy Shevchenko <andy@kernel.org>
To:     Samuel Holland <samuel.holland@sifive.com>
Cc:     Linus Walleij <linus.walleij@linaro.org>,
        Bartosz Golaszewski <brgl@bgdev.pl>,
        Emil Renner Berthing <emil.renner.berthing@canonical.com>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org
Subject: Re: [PATCH v2 3/4] gpio: sifive: Get the parent IRQ's domain from
 its irq_data
Message-ID: <ZLgVPv7zdoaiUCU6@smile.fi.intel.com>
References: <20230719163446.1398961-1-samuel.holland@sifive.com>
 <20230719163446.1398961-4-samuel.holland@sifive.com>
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On Wed, Jul 19, 2023 at 09:34:44AM -0700, Samuel Holland wrote:
> Do not parse the devicetree again when the data is already available
> from the IRQ subsystem. This follows the example of the ThunderX and
> X-Gene GPIO drivers. The ngpio check is needed to avoid a possible
> out-of-bounds read.

...

> -	girq->parent_domain = parent;
> +	girq->parent_domain = irq_get_irq_data(chip->irq_number[0])->domain;

For the sake of readability I would like to leave parent variable
and assign it beforehand somewhere upper in the code.

Also, can irq_get_irq_data() return NULL? Needs a comment on top
of that assignment or an additional check.

-- 
With Best Regards,
Andy Shevchenko