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Subject: Re: [PATCH RFC 0/3] staging: r8188eu: avoid uninit value bugs
To:     Greg KH <gregkh@linuxfoundation.org>
Cc:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
        Larry.Finger@lwfinger.net, phil@philpotter.co.uk,
        straube.linux@gmail.com, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org, Martin Kaiser <martin@kaiser.cx>
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From:   Pavel Skripkin <paskripkin@gmail.com>
Message-ID: <e5d189b7-15b2-8cc3-1e84-021dc5ab51af@gmail.com>
Date:   Sun, 22 Aug 2021 15:50:35 +0300
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On 8/22/21 3:39 PM, Greg KH wrote:
>> 
>> Yes, but _rtw_read*() == 0 indicates 2 states:
>> 
>> 	1. Error on transfer side
>> 	2. Actual register value is 0
> 
> That's not a good design, it should be fixed.  Note there is the new
> usb_control_msg_recv() function which should probably be used instead
> here, to prevent this problem from happening.
> 

Thank you, Greg, for confirmation. That's was the point why I started to 
write this series :)

I think, usb_control_msg_recv() won't help us with this problem, since 
all rtw_read*() functions return an unsigned value now. In future, when 
driver code will be fixed (ex: a lot of void function, which can fail 
and leave passed pointer uninitialized) we can move to new usb API and 
then move driver out of staging :)


With regards,
Pavel Skripkin