Re: [PATCH net] wifi: airo: avoid uninitialized warning in airo_get_rate()

[Randy Dunlap]

Hi Simon,

On 7/11/23 10:25, Simon Horman wrote:
> On Sun, Jul 09, 2023 at 06:31:54AM -0700, Randy Dunlap wrote:
>> Quieten a gcc (11.3.0) build error or warning by checking the function
>> call status and returning -EBUSY if the function call failed.
>> This is similar to what several other wireless drivers do for the
>> SIOCGIWRATE ioctl call when there is a locking problem.
>>
>> drivers/net/wireless/cisco/airo.c: error: 'status_rid.currentXmitRate' is used uninitialized [-Werror=uninitialized]
> 
> Hi Randy,
> 
> There seem to be other calls to readStatusRid() in the same file
> with similar properties. Perhaps it would be best to fix them too?
> 

Yes, there are 40+ calls that could have problems.
Please see this thread:
  https://lore.kernel.org/all/2f6ffd1c-a756-b7b8-bba4-77c2308f26b9@xxxxxxxxxxxxx/

This is an attempt to shut up the build error/warning, which only occurs after
this one function call.

For such an old driver/hardware, I don't plan to do massive surgery
to it.

>> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>> Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>> Reported-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
>> Link: lore.kernel.org/r/39abf2c7-24a-f167-91da-ed4c5435d1c4@xxxxxxxxxxxxxx
>> Cc: Kalle Valo <kvalo@xxxxxxxxxx>
>> Cc: linux-wireless@xxxxxxxxxxxxxxx
>> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
>> Cc: Eric Dumazet <edumazet@xxxxxxxxxx>
>> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
>> Cc: Paolo Abeni <pabeni@xxxxxxxxxx>
>> Cc: netdev@xxxxxxxxxxxxxxx
>> ---
>>  drivers/net/wireless/cisco/airo.c |    5 ++++-
>>  1 file changed, 4 insertions(+), 1 deletion(-)
>>
>> diff -- a/drivers/net/wireless/cisco/airo.c b/drivers/net/wireless/cisco/airo.c
>> --- a/drivers/net/wireless/cisco/airo.c
>> +++ b/drivers/net/wireless/cisco/airo.c
>> @@ -6157,8 +6157,11 @@ static int airo_get_rate(struct net_devi
>>  	struct iw_param *vwrq = &wrqu->bitrate;
>>  	struct airo_info *local = dev->ml_priv;
>>  	StatusRid status_rid;		/* Card status info */
>> +	int ret;
>>  
>> -	readStatusRid(local, &status_rid, 1);
>> +	ret = readStatusRid(local, &status_rid, 1);
>> +	if (ret)
>> +		return -EBUSY;
>>  
>>  	vwrq->value = le16_to_cpu(status_rid.currentXmitRate) * 500000;
>>  	/* If more than one rate, set auto */
>>

-- 
~Randy