Re: [Qemu-devel] [RFC] sync NIC's MAC maintained in NICConf as soon as emualted NIC's MAC changed in guest

[Michael S. Tsirkin]

On Sun, Sep 22, 2013 at 08:35:29AM +0000, Zhanghaoyu (A) wrote:
> Hi, all
> 
> Do live migration if emulated NIC's MAC has been changed, RARP with wrong MAC 
> address will broadcast via qemu_announce_self in destination,
> so, long time network disconnection probably happen.

Good catch.

> I want to do below works to resolve this problem,
> 1. change NICConf's MAC as soon as emulated NIC's MAC changed in guest

This will make it impossible to revert it correctly on reset, won't it?

> 2. sync NIC's (more precisely, queue) MAC to corresponding NICConf in NIC's 
> migration load handler
> 
> Any better ideas?
> 
> Thanks,
> Zhang Haoyu

I think announce needs to poke at the current MAC instead of
the default one in NICConf.
We can make it respect link down state while we are at it.

Happily recent linux guests aren't affected since
they do announcements from guest.

-- 
MST