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Message-ID: <dbf0d09e-6b59-4dfe-8010-b530e2f305b0@linux.ibm.com>
Date:   Wed, 13 Dec 2023 20:09:09 -0600
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH v1] fsi: Fix panic on scom file read
Content-Language: en-US
To:     Lakshmi Yadlapati <lakshmiy@us.ibm.com>, joel@jms.id.au,
        eajames@linux.ibm.com, alistair@popple.id.au
Cc:     linux-fsi@lists.ozlabs.org, linux-kernel@vger.kernel.org
References: <20231214000744.1281464-1-lakshmiy@us.ibm.com>
From:   Ninad Palsule <ninad@linux.ibm.com>
In-Reply-To: <20231214000744.1281464-1-lakshmiy@us.ibm.com>
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Hi Lakshmi,

On 12/13/23 18:07, Lakshmi Yadlapati wrote:
> Reading the scom file without the custom open method (i2cr_scom_open)
> causes a kernel panic. This change replaces simple_open with i2cr_scom_open
> to properly initialize the private_data field in the file structure,
> preventing the panic during scom file operations.
>
> Signed-off-by: Lakshmi Yadlapati <lakshmiy@us.ibm.com>
> ---
>   drivers/fsi/i2cr-scom.c | 11 ++++++++++-
>   1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/fsi/i2cr-scom.c b/drivers/fsi/i2cr-scom.c
> index cb7e02213032..8d65c562b488 100644
> --- a/drivers/fsi/i2cr-scom.c
> +++ b/drivers/fsi/i2cr-scom.c
> @@ -73,9 +73,18 @@ static ssize_t i2cr_scom_write(struct file *filep, const char __user *buf, size_
>   	return len;
>   }
>   
> +static int i2cr_scom_open(struct inode *inode, struct file *file)
> +{
> +	struct i2cr_scom *scom = container_of(inode->i_cdev, struct i2cr_scom, cdev);
> +
> +	file->private_data = scom;
> +
> +	return 0;
> +}
> +
>   static const struct file_operations i2cr_scom_fops = {
>   	.owner		= THIS_MODULE,
> -	.open		= simple_open,
> +	.open		= i2cr_scom_open,
>   	.llseek		= i2cr_scom_llseek,
>   	.read		= i2cr_scom_read,
>   	.write		= i2cr_scom_write,


Looks good.

Reviewed-by: Ninad Palsule <ninad@linux.ibm.com>