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

[Stephen Hemminger <stephen@networkplumber.org>]

On Fri, 11 May 2018 16:32:24 +0000
"De Lara Guarch, Pablo" <pablo.de.lara.guarch@intel.com> wrote:

> > -----Original Message-----
> > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Andy Green
> > Sent: Friday, May 11, 2018 2:51 AM
> > To: dev@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@dpdk.org
> 

Actually, I didn't write this. It came from contractors.  Based of FreeBSD
driver so look there.