* 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.
What exactly was the error? I don't know much about vmxnet3; but if the guest driver is seeing the problem then I guess that's the best pointer we have. Dave > Thanks, > Marcel > > > > Any help or pointer would be greatly appreciated. > > > Thanks, > > > Marcel > > > > > > > > > [...] > -- Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
