bond_compute_features() does not handle devices with different CSUM

bond_compute_features() does not handle devices with different CSUM

[Laurent Chavey]

kernel version <= 2.6.20.1
file drivers/net/bonding/bonding_main.c
function bond_compute_features()

-----------
  Given a system with two different NIC. One driver sets
        dev->features |=  NETIF_F_HW_CSUM
  the other driver sets
        dev->features |=  NETIF_F_IP_CSUM

  when enslaving the 2 device above, bond_compute_features()
  does not set the intersection of the 2 CSUM
  features (should be NETIF_F_IP_CSUM)
-----------

   should the bond features in the case above include NETIF_F_IP_CSUM

Re: bond_compute_features() does not handle devices with different CSUM

[Laurent Chavey]

proposed change.

--- 2.6.20/drivers/net/bonding/bond_main.c      2007-05-29
19:43:39.010565000 -0700
+++ 2.6.20.fix/drivers/net/bonding/bond_main.c  2007-05-29
19:46:12.376980000 -0700
@@ -1227,7 +1227,14 @@
        int i;

        bond_for_each_slave(bond, slave, i) {
-               features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
+               /* NETIF_F_HW_CSUM includes support for NET_IF_IP_CSUM
+                * as such when looking for the intersection we need to
+                * add it to the device supported features
+                */
+               unsigned long dev_features = slave->dev->features;
+               if (slave->dev->features & NETIF_F_HW_CSUM)
+                       dev_features |= NETIF_F_IP_CSUM;
+               features &= (features & BOND_INTERSECT_FEATURES);
                if (slave->dev->hard_header_len > max_hard_header_len)
                        max_hard_header_len = slave->dev->hard_header_len;
        }



On 5/29/07, Laurent Chavey <chavey@google.com> wrote:
> kernel version <= 2.6.20.1
> file drivers/net/bonding/bonding_main.c
> function bond_compute_features()
>
> -----------
>   Given a system with two different NIC. One driver sets
>         dev->features |=  NETIF_F_HW_CSUM
>   the other driver sets
>         dev->features |=  NETIF_F_IP_CSUM
>
>   when enslaving the 2 device above, bond_compute_features()
>   does not set the intersection of the 2 CSUM
>   features (should be NETIF_F_IP_CSUM)
> -----------
>
>    should the bond features in the case above include NETIF_F_IP_CSUM
>

Re: bond_compute_features() does not handle devices with different CSUM

[Michael Buesch]

On Wednesday 30 May 2007 04:47:09 Laurent Chavey wrote:
> proposed change.
> 
> --- 2.6.20/drivers/net/bonding/bond_main.c      2007-05-29
> 19:43:39.010565000 -0700
> +++ 2.6.20.fix/drivers/net/bonding/bond_main.c  2007-05-29
> 19:46:12.376980000 -0700
> @@ -1227,7 +1227,14 @@
>         int i;
> 
>         bond_for_each_slave(bond, slave, i) {
> -               features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
> +               /* NETIF_F_HW_CSUM includes support for NET_IF_IP_CSUM
> +                * as such when looking for the intersection we need to
> +                * add it to the device supported features
> +                */
> +               unsigned long dev_features = slave->dev->features;
> +               if (slave->dev->features & NETIF_F_HW_CSUM)
> +                       dev_features |= NETIF_F_IP_CSUM;


> +               features &= (features & BOND_INTERSECT_FEATURES);

Is this statement correct?
It's the same as
	features = features & (features & BOND_INTERSECT_FEATURES);
which looks strange to me.
Did you mean something like
	features |= (dev_features & BOND_INTERSECT_FEATURES);
?

-- 
Greetings Michael.

Re: bond_compute_features() does not handle devices with different CSUM

[Laurent Chavey]

features = features & (dev_features & BOND_INTERSECT_FEATURES);

On 5/30/07, Michael Buesch <mb@bu3sch.de> wrote:
> On Wednesday 30 May 2007 04:47:09 Laurent Chavey wrote:
> > proposed change.
> >
> > --- 2.6.20/drivers/net/bonding/bond_main.c      2007-05-29
> > 19:43:39.010565000 -0700
> > +++ 2.6.20.fix/drivers/net/bonding/bond_main.c  2007-05-29
> > 19:46:12.376980000 -0700
> > @@ -1227,7 +1227,14 @@
> >         int i;
> >
> >         bond_for_each_slave(bond, slave, i) {
> > -               features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
> > +               /* NETIF_F_HW_CSUM includes support for NET_IF_IP_CSUM
> > +                * as such when looking for the intersection we need to
> > +                * add it to the device supported features
> > +                */
> > +               unsigned long dev_features = slave->dev->features;
> > +               if (slave->dev->features & NETIF_F_HW_CSUM)
> > +                       dev_features |= NETIF_F_IP_CSUM;
>
>
> > +               features &= (features & BOND_INTERSECT_FEATURES);
>
> Is this statement correct?
> It's the same as
>         features = features & (features & BOND_INTERSECT_FEATURES);
> which looks strange to me.
> Did you mean something like
>         features |= (dev_features & BOND_INTERSECT_FEATURES);
> ?
>
> --
> Greetings Michael.
>

Re: bond_compute_features() does not handle devices with different CSUM

[Laurent Chavey]

corrected diff.

--- 2.6.20/drivers/net/bonding/bond_main.c      2007-05-29
19:43:39.010565000 -0700
+++ 2.6.20.fix/drivers/net/bonding/bond_main.c  2007-05-30
08:18:24.018322000 -0700
@@ -1227,7 +1227,14 @@
        int i;

        bond_for_each_slave(bond, slave, i) {
-               features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
+               /* NETIF_F_HW_CSUM includes support for NET_IF_IP_CSUM
+                * as such when looking for the intersection we need to
+                * add it to the device supported features
+                */
+               unsigned long dev_features = slave->dev->features;
+               if (slave->dev->features & NETIF_F_HW_CSUM)
+                       dev_features |= NETIF_F_IP_CSUM;
+               features &= (dev_features & BOND_INTERSECT_FEATURES);
                if (slave->dev->hard_header_len > max_hard_header_len)
                        max_hard_header_len = slave->dev->hard_header_len;
        }

On 5/30/07, Laurent Chavey <chavey@google.com> wrote:
> features = features & (dev_features & BOND_INTERSECT_FEATURES);
>
> On 5/30/07, Michael Buesch <mb@bu3sch.de> wrote:
> > On Wednesday 30 May 2007 04:47:09 Laurent Chavey wrote:
> > > proposed change.
> > >
> > > --- 2.6.20/drivers/net/bonding/bond_main.c      2007-05-29
> > > 19:43:39.010565000 -0700
> > > +++ 2.6.20.fix/drivers/net/bonding/bond_main.c  2007-05-29
> > > 19:46:12.376980000 -0700
> > > @@ -1227,7 +1227,14 @@
> > >         int i;
> > >
> > >         bond_for_each_slave(bond, slave, i) {
> > > -               features &= (slave->dev->features & BOND_INTERSECT_FEATURES);
> > > +               /* NETIF_F_HW_CSUM includes support for NET_IF_IP_CSUM
> > > +                * as such when looking for the intersection we need to
> > > +                * add it to the device supported features
> > > +                */
> > > +               unsigned long dev_features = slave->dev->features;
> > > +               if (slave->dev->features & NETIF_F_HW_CSUM)
> > > +                       dev_features |= NETIF_F_IP_CSUM;
> >
> >
> > > +               features &= (features & BOND_INTERSECT_FEATURES);
> >
> > Is this statement correct?
> > It's the same as
> >         features = features & (features & BOND_INTERSECT_FEATURES);
> > which looks strange to me.
> > Did you mean something like
> >         features |= (dev_features & BOND_INTERSECT_FEATURES);
> > ?
> >
> > --
> > Greetings Michael.
> >
>

Re: bond_compute_features() does not handle devices with different CSUM

[Stephen Hemminger]

On Tue, 29 May 2007 17:41:45 -0700
"Laurent Chavey" <chavey@google.com> wrote:

> kernel version <= 2.6.20.1
> file drivers/net/bonding/bonding_main.c
> function bond_compute_features()
> 
> -----------
>   Given a system with two different NIC. One driver sets
>         dev->features |=  NETIF_F_HW_CSUM
>   the other driver sets
>         dev->features |=  NETIF_F_IP_CSUM
> 
>   when enslaving the 2 device above, bond_compute_features()
>   does not set the intersection of the 2 CSUM
>   features (should be NETIF_F_IP_CSUM)
> -----------
> 
>    should the bond features in the case above include NETIF_F_IP_CSUM
> -
> To unsubscribe from this list: send the line "unsubscribe netdev" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

The bridge code already has a more complete/complex recompute
routine to handle this.

-- 
Stephen Hemminger <shemminger@linux-foundation.org>

Re: bond_compute_features() does not handle devices with different CSUM

[Laurent Chavey]

should we then move/integrate that code as part of the bonding driver ?


On 5/30/07, Stephen Hemminger <shemminger@linux-foundation.org> wrote:
> On Tue, 29 May 2007 17:41:45 -0700
> "Laurent Chavey" <chavey@google.com> wrote:
>
> > kernel version <= 2.6.20.1
> > file drivers/net/bonding/bonding_main.c
> > function bond_compute_features()
> >
> > -----------
> >   Given a system with two different NIC. One driver sets
> >         dev->features |=  NETIF_F_HW_CSUM
> >   the other driver sets
> >         dev->features |=  NETIF_F_IP_CSUM
> >
> >   when enslaving the 2 device above, bond_compute_features()
> >   does not set the intersection of the 2 CSUM
> >   features (should be NETIF_F_IP_CSUM)
> > -----------
> >
> >    should the bond features in the case above include NETIF_F_IP_CSUM
> > -
> > To unsubscribe from this list: send the line "unsubscribe netdev" in
> > the body of a message to majordomo@vger.kernel.org
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
> The bridge code already has a more complete/complex recompute
> routine to handle this.
>
> --
> Stephen Hemminger <shemminger@linux-foundation.org>
>

Re: bond_compute_features() does not handle devices with different CSUM

[Stephen Hemminger]

On Wed, 30 May 2007 09:58:38 -0700
"Laurent Chavey" <chavey@google.com> wrote:

> should we then move/integrate that code as part of the bonding driver ?
> 
> 
> On 5/30/07, Stephen Hemminger <shemminger@linux-foundation.org> wrote:
> > On Tue, 29 May 2007 17:41:45 -0700
> > "Laurent Chavey" <chavey@google.com> wrote:
> >
> > > kernel version <= 2.6.20.1
> > > file drivers/net/bonding/bonding_main.c
> > > function bond_compute_features()
> > >
> > > -----------
> > >   Given a system with two different NIC. One driver sets
> > >         dev->features |=  NETIF_F_HW_CSUM
> > >   the other driver sets
> > >         dev->features |=  NETIF_F_IP_CSUM
> > >
> > >   when enslaving the 2 device above, bond_compute_features()
> > >   does not set the intersection of the 2 CSUM
> > >   features (should be NETIF_F_IP_CSUM)
> > > -----------
> > >
> > >    should the bond features in the case above include NETIF_F_IP_CSUM
> > > -
> > > To unsubscribe from this list: send the line "unsubscribe netdev" in
> > > the body of a message to majordomo@vger.kernel.org
> > > More majordomo info at  http://vger.kernel.org/majordomo-info.html
> >
> > The bridge code already has a more complete/complex recompute
> > routine to handle this.
> >
> > --
> > Stephen Hemminger <shemminger@linux-foundation.org>
> >

Sure, that would be easier for maintenance.

-- 
Stephen Hemminger <shemminger@linux-foundation.org>