[dpdk-dev] [PATCH 2/4] net/bnx2x: remove unmeetable comparison

[Andy Green]

On 05/12/2018 02:10 AM, Stephen Hemminger wrote:
> On Fri, 11 May 2018 16:32:24 +0000
> "De Lara Guarch, Pablo" <pablo.de.lara.guarch at intel.com> wrote:
> 
>>> -----Original Message-----
>>> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Andy Green
>>> Sent: Friday, May 11, 2018 2:51 AM
>>> To: dev at dpdk.org
>>> Subject: [dpdk-dev] [PATCH 2/4] net/bnx2x: remove unmeetable comparison
>>>
>>> /home/agreen/projects/dpdk/drivers/net/bnx2x/elink.c:
>>> In function ‘elink_check_kr2_wa’:
>>> /home/agreen/projects/dpdk/drivers/net/bnx2x/elink.c:12922:28:
>>> error: bitwise comparison always evaluates to false [-Werror=tautological-
>>> compare]
>>>          ((next_page & 0xe0) == 0x2))));
>>> ---
>>>   drivers/net/bnx2x/elink.c |    4 +---
>>>   1 file changed, 1 insertion(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/net/bnx2x/elink.c b/drivers/net/bnx2x/elink.c index
>>> 99684a5f9..2aef2b6da 100644
>>> --- a/drivers/net/bnx2x/elink.c
>>> +++ b/drivers/net/bnx2x/elink.c
>>> @@ -12919,9 +12919,7 @@ static void elink_check_kr2_wa(struct elink_params
>>> *params,
>>>   	 * but only KX is advertised, declare this link partner as non-KR2
>>>   	 * device.
>>>   	 */
>>> -	not_kr2_device = (((base_page & 0x8000) == 0) ||
>>> -			  (((base_page & 0x8000) &&
>>> -			    ((next_page & 0xe0) == 0x2))));
>>> +	not_kr2_device = !(base_page & 0x8000);
>>>
>>>   	/* In case KR2 is already disabled, check if we need to re-enable it */
>>>   	if (!(vars->link_attr_sync & LINK_ATTR_SYNC_KR2_ENABLE)) {
>>
>> Looks like a good fix, but I wonder what's the actual intention of that conditional.
>> CC'ing the maintainers and Stephen Hemminger (the author of this code) to figure it out.
>>
>> Apart from that, missing signed-off-by, fixes line and Cc stable:
>>
>> Fixes: b5bf7719221d ("bnx2x: driver support routines")
>> Cc: stable at dpdk.org
>>
> 
> Actually, I didn't write this. It came from contractors.  Based of FreeBSD
> driver so look there.

Googling around, the correct comparison is == 0x20, I updated the patch 
accordingly.

-Andy