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Subject: Re: [Qemu-devel] [PATCH 1/1] net: fix queue's purge on VM stop
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To: Thibaut Collet <thibaut.collet@6wind.com>, Stefan Hajnoczi <stefanha@redhat.com>
Cc: Stefan Hajnoczi <stefanha@gmail.com>, Giuseppe Lettieri <g.lettieri@iet.unipi.it>, Luigi Rizzo <rizzo@iet.unipi.it>, qemu-devel@nongnu.org, Vincenzo Maffione <v.maffione@gmail.com>



On 06/03/2015 03:56 PM, Thibaut Collet wrote:
> Hi,
>
> thanks for your point, I did not notice the problem of the lost of ARP
> announce by discarding the message. 
> So I must rewrite my patch to define a queue to transmit the ARP
> announce to the guest. Is it the proper solution?
>

Please have a look at VIRTIO_NET_F_GUEST_ANNOUNCE. It can notify guest
after migration to let it to send arp announce. Recent linux driver has
this support.

> Thanks.
>
> Best regards.
>
> Thibaut.
>
> On Tue, Jun 2, 2015 at 12:34 PM, Stefan Hajnoczi <stefanha@redhat.com
> <mailto:stefanha@redhat.com>> wrote:
>
>     On Fri, May 29, 2015 at 04:28:48PM +0200, Thibaut Collet wrote:
>     > I agree that virtio-net NIC never enqueues packet to vhost-user
>     > but qemu_announce_self function (savevm.c file) can do it through
>     > the qemu_announce_self_iter / qemu_send_packet_raw sequence.
>
>     Does vhost-user support live migration?
>
>     If no, then qemu_announce_self is never called.
>
>     If yes, then the packet should not be discarded since the ARP announce
>     has a purpose.
>
>     Stefan
>
>