Re: [PATCH net-next v2] net: generic dev_disable_lro() stacked device handling

From: David Miller
Date: Thu Nov 13 2014 - 14:49:36 EST


From: Michal Kubecek <mkubecek@xxxxxxx>
Date: Thu, 13 Nov 2014 07:54:50 +0100 (CET)

> Large receive offloading is known to cause problems if received packets
> are passed to other host. Therefore the kernel disables it by calling
> dev_disable_lro() whenever a network device is enslaved in a bridge or
> forwarding is enabled for it (or globally). For virtual devices we need
> to disable LRO on the underlying physical device (which is actually
> receiving the packets).
>
> Current dev_disable_lro() code handles this propagation for a vlan
> (including 802.1ad nested vlan), macvlan or a vlan on top of a macvlan.
> It doesn't handle other stacked devices and their combinations, in
> particular propagation from a bond to its slaves which often causes
> problems in virtualization setups.
>
> As we now have generic data structures describing the upper-lower device
> relationship, dev_disable_lro() can be generalized to disable LRO also
> for all lower devices (if any) once it is disabled for the device
> itself.
>
> For bonding and teaming devices, it is necessary to disable LRO not only
> on current slaves at the moment when dev_disable_lro() is called but
> also on any slave (port) added later.
>
> v2: use lower device links for all devices (including vlan and macvlan)
>
> Signed-off-by: Michal Kubecek <mkubecek@xxxxxxx>

Applied, thanks a lot.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/