Hi mellanox team,
I test the mlx5 vdpa in linux-5.9 and meet several problem. # lspci | grep Ether | grep Dx b3:00.0 Ethernet controller: Mellanox Technologies MT2892 Family [ConnectX-6 Dx] b3:00.1 Ethernet controller: Mellanox Technologies MT2892 Family [ConnectX-6 Dx] # ethtool -i net2 driver: mlx5e_rep version: 5.9.0 firmware-version: 22.28.1002 (MT_0000000430) expansion-rom-version: bus-info: 0000:b3:00.0 supports-statistics: yes supports-test: no supports-eeprom-access: no supports-register-dump: no supports-priv-flags: no init switchdev: # echo 1 > /sys/class/net/net2/device/sriov_numvfs # echo 0000:b3:00.2 > /sys/bus/pci/drivers/mlx5_core/unbind # devlink dev eswitch set pci/0000:b3:00.0 mode switchdev encap enable # modprobe vdpa vhost-vdpa mlx5_vdpa # ip l set dev net2 vf 0 mac 52:90:01:00:02:13 # echo 0000:b3:00.2 > /sys/bus/pci/drivers/mlx5_core/bind setup vm: # qemu-system-x86_64 -name test -enable-kvm -smp 16,sockets=2,cores=8,threads=1 -m 8192 -drive file=./centos7.qcow2,format=qcow2,if=none,id=drive-virtio-disk0 -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x7,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -netdev type=vhost-vdpa,vhostdev=/dev/vhost-vdpa-0,id=vhost-vdpa0 -device virtio-net-pci,netdev=vhost-vdpa0,page-per-vq=on,iommu_platform=on,id=net0,bus=pci.0,addr=0x3,disable-legacy=on -vnc 0.0.0.0:0 In the vm: virtio net device eth0 with ip address 10.0.0.75/24 On the host: VF0 rep device pf0vf0 with ip address 10.0.0.7/24 problem 1: On the host: # ping 10.0.0.75 Some times there will be loss packets. And in the VM: dmesg shows: eth0: bad tso: type 100, size: 0 eth0: bad tso: type 10, size: 28 So I think maybe the vnet header is not init with 0? And Then I clear the gso_type, gso_size and flags in the virtio_net driver. There is no packets dropped. problem 2: In the vm: iperf -s On the host: iperf -c 10.0.0.75 -t 100 -i 2. The tcp connection can't established for the syn+ack with partail cum but not handle correct by hardware. After I set the csum off for eth0 in the vm, the problem is resolved. Although the mlx5_vnet support VIRTIO_NET_F_CSUM feature. problem 3: The iperf perofrmance not stable before I disable the pf0vf0 tso offload #ethtool -K pf0vf0 tso off I know the mlx5_vnet did not support feature VIRTIO_NET_F_GUEST_TSO4. But the hardware can't cut the big tso packet to several small tcp packet and send to virtio net device? BR wenxu
