Date:   Sun, 12 Dec 2021 18:26:58 +0000
Message-ID: <87pmq1u1al.wl-maz@kernel.org>
From:   Marc Zyngier <maz@kernel.org>
To:     Hector Martin <marcan@marcan.st>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Rob Herring <robh+dt@kernel.org>,
        Sven Peter <sven@svenpeter.dev>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org
Subject: Re: [PATCH 4/6] irqchip/apple-aic: Dynamically compute register offsets
In-Reply-To: <20211209043249.65474-5-marcan@marcan.st>
References: <20211209043249.65474-1-marcan@marcan.st>
        <20211209043249.65474-5-marcan@marcan.st>
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On Thu, 09 Dec 2021 04:32:47 +0000,
Hector Martin <marcan@marcan.st> wrote:
> 
> This allows us to support AIC variants with different numbers of IRQs
> based on capability registers.
> 
> Signed-off-by: Hector Martin <marcan@marcan.st>
> ---
>  drivers/irqchip/irq-apple-aic.c | 73 +++++++++++++++++++++++++--------
>  1 file changed, 56 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c
> index 572d1af175fc..d03caed51d56 100644
> --- a/drivers/irqchip/irq-apple-aic.c
> +++ b/drivers/irqchip/irq-apple-aic.c
> @@ -312,12 +326,15 @@ static int aic_irq_set_affinity(struct irq_data *d,
>  	struct aic_irq_chip *ic = irq_data_get_irq_chip_data(d);
>  	int cpu;
>  
> +	if (!ic->info.target_cpu)
> +		return -EINVAL;

Can this even happen? And if it did, this should scream loudly,
shouldn't it?

	M.

-- 
Without deviation from the norm, progress is not possible.