> On 25 Jun 2019, at 11:49, Marcel Apfelbaum <marcel.apfelb...@gmail.com> wrote:
>
> Hi Dmitry,
>
> On 6/25/19 11:39 AM, Dmitry Fleytman wrote:
>>
>>> On 25 Jun 2019, at 11:14, Marcel Apfelbaum <marcel.apfelb...@gmail.com>
>>> wrote:
>>>
>>> Hi Sukrit
>>>
>>> On 6/21/19 5:45 PM, Sukrit Bhatnagar wrote:
>>>> Hi,
>>> [...]
>>>> This RFC is meant to request suggestions on the things which are
>>>> working and for help on the things which are not.
>>>>
>>> [...]
>>>> What is not working:
>>>>
>>> [...]
>>>> * It seems that vmxnet3 migration itself is not working properly, at least
>>>> for me. The pvrdma device depends on it, vmxnet3 is function 0 and pvrdma
>>>> is function 1. This is happening even for a build of unmodified code from
>>>> the master branch.
>>>> After migration, the network connectivity is lost at destination.
>>>> Things are fine at the source before migration.
>>>> This is the command I am using at src:
>>>>
>>>> sudo /home/skrtbhtngr/qemu/build/x86_64-softmmu/qemu-system-x86_64 \
>>>> -enable-kvm \
>>>> -m 2G -smp cpus=2 \
>>>> -hda /home/skrtbhtngr/fedora.img \
>>>> -netdev tap,id=hostnet0 \
>>>> -device vmxnet3,netdev=hostnet0,id=net0,mac=52:54:00:99:ff:bc \
>>>> -monitor telnet:127.0.0.1:4444,server,nowait \
>>>> -trace events=/home/skrtbhtngr/trace-events \
>>>> -vnc 0.0.0.0:0
>>>>
>>>> Similar command is used for the dest. Currently, I am trying
>>>> same-host migration for testing purpose, without the pvrdma device.
>>>> Two tap interfaces, for src and dest were created successfully at
>>>> the host. Kernel logs:
>>>> ...
>>>> br0: port 2(tap0) entered forwarding state
>>>> ...
>>>> br0: port 3(tap1) entered forwarding state
>>>>
>>>> tcpdump at the dest reports only outgoing ARP packets, which ask
>>>> for gateway: "ARP, Request who-has _gateway tell guest1".
>>>>
>>>> Tried using user (slirp) as the network backend, but no luck.
>>>> Also tried git bisect to find the issue using a working commit (given
>>>> by Marcel), but it turns out that it is very old and I faced build
>>>> errors one after another.
>>>>
>>>> Please note that e1000 live migration is working fine in the same setup.
>>>>
>>> I tried to git bisect , but I couldn't find a working version of vmxnet
>>> supporting live migration ....
>>> I tried even a commit from December 2014 and it didn't work.
>>>
>>> What is strange (to me) is that the networking packets can't be sent from
>>> the guest (after migration)
>>> even after rebooting the guest.
>> This makes me think that some network offload configuration wasn’t properly
>> migrated or applied.
>> What network backend are you using?
>
> Suktrit tried with tap device, I tried with slirp.
> If you can point me to the property that disables all the offloads it will
> really help.
>
>> Do you see any outgoing packets in the sniffer?
>
> I didn't use the sniffer, I checked dmesg in guest, there was a line
> complaining that it can't send packets.
I see. If it cannot send packet on the guest side, then it’s not an offload.
A snippet from dmesg will be helpful indeed.
>
> Thanks,
> Marcel
>
>>> Any help or pointer would be greatly appreciated.
>>> Thanks,
>>> Marcel
>>>
>>>
>>> [...]