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Date:   Fri, 5 Aug 2022 11:31:17 -0700
From:   Ira Weiny <ira.weiny@intel.com>
To:     Bo Liu <liubo03@inspur.com>
CC:     <dan.j.williams@intel.com>, <vishal.l.verma@intel.com>,
        <dave.jiang@intel.com>, <nvdimm@lists.linux.dev>,
        <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] dax: Check dev_set_name() return value
Message-ID: <Yu1h9QB2eTqg6eWn@iweiny-desk3>
References: <20220805053319.3865-1-liubo03@inspur.com>
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On Fri, Aug 05, 2022 at 01:33:19AM -0400, Bo Liu wrote:
> It's possible that dev_set_name() returns -ENOMEM, catch and handle this.

Did this cause a bug or some other problem when the name was not set?

I think it is an ok change but without digging into the code I'm not clear why
you did this.

Ira

> 
> Signed-off-by: Bo Liu <liubo03@inspur.com>
> ---
>  drivers/dax/bus.c | 11 +++++++++--
>  1 file changed, 9 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c
> index 1dad813ee4a6..36cf245ee467 100644
> --- a/drivers/dax/bus.c
> +++ b/drivers/dax/bus.c
> @@ -765,7 +765,12 @@ static int devm_register_dax_mapping(struct dev_dax *dev_dax, int range_id)
>  	device_initialize(dev);
>  	dev->parent = &dev_dax->dev;
>  	dev->type = &dax_mapping_type;
> -	dev_set_name(dev, "mapping%d", mapping->id);
> +	rc = dev_set_name(dev, "mapping%d", mapping->id);
> +	if (rc) {
> +		kfree(mapping);
> +		return rc;
> +	}
> +
>  	rc = device_add(dev);
>  	if (rc) {
>  		put_device(dev);
> @@ -1334,7 +1339,9 @@ struct dev_dax *devm_create_dev_dax(struct dev_dax_data *data)
>  	dev_dax->region = dax_region;
>  	dev = &dev_dax->dev;
>  	device_initialize(dev);
> -	dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id);
> +	rc = dev_set_name(dev, "dax%d.%d", dax_region->id, dev_dax->id);
> +	if (rc)
> +		goto err_range;
>  
>  	rc = alloc_dev_dax_range(dev_dax, dax_region->res.start, data->size);
>  	if (rc)
> -- 
> 2.27.0
> 
>