Hi Paolo, Am 06.11.2017 um 10:40 schrieb Paolo Bonzini: > On 06/11/2017 10:38, Stefan Priebe - Profihost AG wrote: >> Hello, >> >> i've upgraded some servers from kernel 4.4 to 4.12 - both running Qemu >> 2.9.1. >> >> If i migrate a VM from a host running kernel 4.4 to a host running 4.12 >> i get: >> >> kvm: virtio-net: saved image requires TUN_F_UFO support >> kvm: Failed to load virtio-net-device:tmp >> kvm: Failed to load virtio-net:virtio >> kvm: error while loading state for instance 0x0 of device >> '0000:00:12.0/virtio-net' >> kvm: load of migration failed: Invalid argument >> >> >> while migrating from 4.12 to 4.4 works fine. >> >> Can anybody help? Is this expected? > > Can you check why peer_has_ufo failed (in hw/net/virtio-net.c)?
May be - how can i archieve this? Patching the code is not a problem if you can give me a hint. > Also, did this ioctl fail when the tap device was set up on the 4.12 > destination? > int tap_probe_has_ufo(int fd) > { > unsigned offload; > > offload = TUN_F_CSUM | TUN_F_UFO; > > if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) > return 0; > > return 1; > } Should there be any kernel output or how can i detect / check it? Greets, Stefan > Thanks, > > Paolo >