Re: [Qemu-devel] [PATCH] net: fix qemu_announce_self not emitting packets

[Peter Lieven <pl@kamp.de>]

Am 07.06.2016 um 09:55 schrieb Paolo Bonzini:
>
> On 07/06/2016 09:37, Peter Lieven wrote:
>> commit fefe2a78 accidently dropped the code path for injecting
>> raw packets. This feature is needed for sending gratuitous ARPs
>> after an incoming migration has completed. The result is increased
>> network downtime for vservers where the network card is not virtio-net
>> with the VIRTIO_NET_F_GUEST_ANNOUNCE feature.
>>
>> Fixes: fefe2a78abde932e0f340b21bded2c86def1d242
>> Cc: qemu-stable@nongnu.org
>> Cc: yanghy@cn.fujitsu.com
>> Signed-off-by: Peter Lieven <pl@kamp.de>
>> ---
>>   net/net.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/net/net.c b/net/net.c
>> index 5f3e5a9..d5834ea 100644
>> --- a/net/net.c
>> +++ b/net/net.c
>> @@ -722,7 +722,11 @@ ssize_t qemu_deliver_packet_iov(NetClientState *sender,
>>           return 0;
>>       }
>>   
>> -    if (nc->info->receive_iov) {
>> +    if (flags & QEMU_NET_PACKET_FLAG_RAW && iovcnt == 1 &&
>> +        nc->info->receive_raw) {
>> +        /* this is required for qemu_announce_self() */
>> +        ret = nc->info->receive_raw(nc, iov[0].iov_base, iov[0].iov_len);
> Possibly move "iovcnt == 1" from the if condition to an assertion inside it?

I do not know if there is any other user that emits raw packets than qemu_announce_self.

The question is do you want to abort or just return -1 (which is the case without this patch).

Peter