Re: tools: propogate MTU to vif frontends (backporting)

["Durrant, Paul" <xadimgnik@xxxxxxxxx>]

On 14/02/2022 10:48, James Dingwall wrote:
> Hi,
>
> I've been backporting this series to xen 4.14 and everything relating to the
> backend seems to be working well.  For the frontend I can see the mtu value
> published to xenstore but it does't appear to be consumed to set the matching
> mtu in the guest.
>
> https://lists.xenproject.org/archives/html/xen-devel/2020-08/msg00458.html
>
> Is the expected solution a custom script running in the guest to make the
> necessary change or have I missed something in how this is supposed to
> operate?
It depends on your guest. Linux happily gets the MTU from DHCP, but 
Windows does not. Hence:
https://xenbits.xen.org/gitweb/?p=pvdrivers/win/xenvif.git;a=blob;f=src/xenvif/mac.c;;hb=HEAD#l440

Cheers,

  Paul