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Message-ID: <7dad295f-2ac4-d6ff-8d8a-17db8ef18c12@gmail.com>
Date:   Fri, 6 May 2022 10:23:39 +0300
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Subject: Re: [PATCH v2 1/2] staging: rtl8712: fix uninit-value in usb_read8()
 and friends
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To:     Wang Cheng <wanngchenng@gmail.com>, dan.carpenter@oracle.com
Cc:     linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org
References: <cover.1651760402.git.wanngchenng@gmail.com>
 <b9b7a6ee02c02aa28054f5cf16129977775f3cd9.1651760402.git.wanngchenng@gmail.com>
From:   Pavel Skripkin <paskripkin@gmail.com>
In-Reply-To: <b9b7a6ee02c02aa28054f5cf16129977775f3cd9.1651760402.git.wanngchenng@gmail.com>
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Hi Wang,

On 5/6/22 06:15, Wang Cheng wrote:
> When r8712_usbctrl_vendorreq() returns negative, 'data' in
> usb_read{8,16,32} will not be initialized.

[code snip]

> +	status = r8712_usbctrl_vendorreq(intfpriv, request, wvalue, index,
> +					 &data, len, requesttype);
> +	if (status < 0)
> +		return 0;
>   	return le32_to_cpu(data);
>   }
>   

Why do you believe that 0 is not valid register value? And if it's 
possible then how you can identify an error?


With regards,
Pavel Skripkin