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Date:   Fri, 15 Oct 2021 10:24:54 +0100
From:   Marc Zyngier <maz@kernel.org>
To:     zhaoxiao <long870912@gmail.com>
Cc:     chenhuacai@kernel.org, jiaxun.yang@flygoat.com, tglx@linutronix.de,
        linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org,
        zhaoxiao <zhaoxiao@uniontech.com>
Subject: Re: [PATCH] irqchip/loongson-htvec:- Handle return value of ioremap.
In-Reply-To: <20211015072523.30615-1-long870912@gmail.com>
References: <20211015072523.30615-1-long870912@gmail.com>
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On 2021-10-15 08:25, zhaoxiao wrote:
> From: zhaoxiao <zhaoxiao@uniontech.com>
> 
> Here, If ioremap will fail. It will return NULL.Kernel can run into
> a NULL-pointer dereference. This error check will avoid NULL pointer
> dereference.
> 
> Signed-off-by: zhaoxiao <zhaoxiao@uniontech.com>
> ---
>  drivers/irqchip/irq-loongson-htvec.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/irqchip/irq-loongson-htvec.c
> b/drivers/irqchip/irq-loongson-htvec.c
> index 1cc0bceb4472..a36c20f44ec4 100644
> --- a/drivers/irqchip/irq-loongson-htvec.c
> +++ b/drivers/irqchip/irq-loongson-htvec.c
> @@ -267,6 +267,8 @@ struct fwnode_handle *htvec_acpi_init(struct
> fwnode_handle *parent,
> 
>  	priv->num_parents = HTVEC_MAX_PARENT_IRQ;
>  	priv->base = ioremap(acpi_htvec->address, acpi_htvec->size);
> +	if (!priv->base)
> +		goto free_priv;
> 
>  	/* Interrupt may come from any of the 8 interrupt lines */
>  	for (i = 0; i < priv->num_parents; i++)
> @@ -307,6 +309,7 @@ struct fwnode_handle *htvec_acpi_init(struct
> fwnode_handle *parent,
>  iounmap_base:
>  	iounmap(priv->base);
>  	priv->domain_handle = NULL;
> +free_priv:
>  	kfree(priv);
> 
>  	return NULL;

What is the difference between this and the patch you sent 3 days ago?

         M.
-- 
Jazz is not dead. It just smells funny...