Re: [Bonding] Should we support qemu/virtio for 802.3ad mode?

[Hangbin Liu <liuhangbin@gmail.com>]

HI Nikolay,

Thanks for your info. I will ask if the customer is OK to set the speed manually.

Regards
Hangbin

On Mon, Jul 01, 2024 at 01:27:54PM +0300, Nikolay Aleksandrov wrote:
> On 01/07/2024 13:11, Hangbin Liu wrote:
> > Hi Jay,
> > 
> > Some one propose again[1] if we should support 802.3ad mode for virtio driver.
> > What do you think? Should we treat the SPEED_UNKNOWN as 1 or something else
> > in __get_link_speed()?
> > 
> > [1] https://lore.kernel.org/all/CAJO99TmB3957Wq3Cse7azgBxKeZ2BV6QihoyAsjUjyvzc-V8dQ@mail.gmail.com/
> > 
> > Thanks
> > Hangbin
> 
> Hi Hangbin,
> Because of 802.3ad we added:
>  commit 16032be56c1f
>  Author: Nikolay Aleksandrov <razor@blackwall.org>
>  Date:   Wed Feb 3 04:04:37 2016 +0100
> 
>     virtio_net: add ethtool support for set and get of settings
>     
>     This patch allows the user to set and retrieve speed and duplex of the
>     virtio_net device via ethtool. Having this functionality is very helpful
>     for simulating different environments and also enables the virtio_net
>     device to participate in operations where proper speed and duplex are
>     required (e.g. currently bonding lacp mode requires full duplex). Custom
>     speed and duplex are not allowed, the user-supplied settings are validated
>     before applying.
>     
>     Example:
>     $ ethtool eth1
>     Settings for eth1:
>     ...
>             Speed: Unknown!
>             Duplex: Unknown! (255)
>     $ ethtool -s eth1 speed 1000 duplex full
>     $ ethtool eth1
>     Settings for eth1:
>     ...
>             Speed: 1000Mb/s
>             Duplex: Full
>     
>     Based on a patch by Roopa Prabhu.
>     
>     Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
> 
> You can set any link parameters and use virtio_net with bond/lacp today.
> 
> Cheers,
>  Nik