Description of problem:
Testpmd command run failed with max-pkt-len=2000 inside guest

Version-Release number of selected component (if applicable):
dpdk-18.11-2.el8.x86_64
dpdk-tools-18.11-2.el8.x86_64
dpdk-18.11-2.el7_6.x86_64
dpdk-tools-18.11-2.el7_6.x86_64

How reproducible:


Steps to Reproduce:
1.Add two guest port to ovs bridge
ovs-vsctl set Open_vSwitch . other_config={}
ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-init=true
ovs-vsctl --no-wait set Open_vSwitch . other_config:dpdk-socket-mem="1024,1024"
ovs-vsctl set Open_vSwitch . other_config:pmd-cpu-mask=500000500000
ovs-vsctl --no-wait set Open_vSwitch . other_config:vhost-iommu-support=true
ovs-vsctl add-port ovsbr0 dpdkvhostuserclient0 -- set Interface dpdkvhostuserclient0 type=dpdkvhostuserclient -- set Interface dpdkvhostuserclient0 options:vhost-server-path=/tmp/dpdkvhostuserclient0
ovs-vsctl add-port ovsbr0 dpdkvhostuserclient1 -- set Interface dpdkvhostuserclient1 type=dpdkvhostuserclient -- set Interface dpdkvhostuserclient1 options:vhost-server-path=/tmp/dpdkvhostuserclient1

2.Start guest.
Guest xml as following.
[root@netqe22 ~]# virsh dumpxml master
<domain type='kvm'>
  <name>master</name>
  <uuid>37425e76-af6a-44a6-aba0-73434afe34c0</uuid>
  <memory unit='KiB'>8388608</memory>
  <currentMemory unit='KiB'>8388608</currentMemory>
  <memoryBacking>
    <hugepages>
      <page size='1048576' unit='KiB'/>
    </hugepages>
    <access mode='shared'/>
  </memoryBacking>
  <vcpu placement='static'>3</vcpu>
  <cputune>
    <vcpupin vcpu='0' cpuset='1'/>
    <vcpupin vcpu='1' cpuset='2'/>
    <vcpupin vcpu='2' cpuset='3'/>
    <emulatorpin cpuset='1'/>
  </cputune>
  <numatune>
    <memory mode='strict' nodeset='0'/>
  </numatune>
  <resource>
    <partition>/machine</partition>
  </resource>
  <os>
    <type arch='x86_64' machine='pc-q35-rhel7.5.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pmu state='off'/>
    <vmport state='off'/>
    <ioapic driver='qemu'/>
  </features>
  <cpu mode='host-passthrough' check='none'>
    <feature policy='require' name='tsc-deadline'/>
    <numa>
      <cell id='0' cpus='0-2' memory='8388608' unit='KiB' memAccess='shared'/>
    </numa>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <pm>
    <suspend-to-mem enabled='no'/>
    <suspend-to-disk enabled='no'/>
  </pm>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='/root/rhel8.0-vsperf-1Q-viommu.qcow2'/>
      <target dev='vda' bus='virtio'/>
      <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
    </disk>
    <controller type='usb' index='0' model='none'/>
    <controller type='pci' index='0' model='pcie-root'/>
    <controller type='pci' index='1' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='1' port='0x10'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </controller>
    <controller type='pci' index='2' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='2' port='0x11'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </controller>
    <controller type='pci' index='3' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='3' port='0x8'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </controller>
    <controller type='pci' index='4' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='4' port='0x9'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </controller>
    <controller type='pci' index='5' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='5' port='0xa'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </controller>
    <controller type='pci' index='6' model='pcie-root-port'>
      <model name='pcie-root-port'/>
      <target chassis='6' port='0xb'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
    </controller>
    <controller type='sata' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
    </controller>
    <interface type='vhostuser'>
      <mac address='52:54:00:11:8f:e8'/>
      <source type='unix' path='/tmp/dpdkvhostuserclient0' mode='server'/>
      <model type='virtio'/>
      <driver name='vhost' iommu='on' ats='on'/>
      <address type='pci' domain='0x0000' bus='0x03' slot='0x00' function='0x0'/>
    </interface>
    <interface type='vhostuser'>
      <mac address='52:54:00:11:8f:e9'/>
      <source type='unix' path='/tmp/dpdkvhostuserclient1' mode='server'/>
      <model type='virtio'/>
      <driver name='vhost' iommu='on' ats='on'/>
      <address type='pci' domain='0x0000' bus='0x04' slot='0x00' function='0x0'/>
    </interface>
    <interface type='bridge'>
      <mac address='52:54:00:bb:63:7b'/>
      <source bridge='virbr0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
    </serial>
    <serial type='pty'>
      <target type='isa-serial' port='0'>
        <model name='isa-serial'/>
      </target>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <input type='mouse' bus='ps2'/>
    <input type='keyboard' bus='ps2'/>
    <graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0'>
      <listen type='address' address='0.0.0.0'/>
    </graphics>
    <video>
      <model type='cirrus' vram='16384' heads='1' primary='yes'/>
      <address type='pci' domain='0x0000' bus='0x05' slot='0x00' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x06' slot='0x00' function='0x0'/>
    </memballoon>
    <iommu model='intel'>
      <driver intremap='on' caching_mode='on' iotlb='on'/>
    </iommu>
  </devices>
  <seclabel type='dynamic' model='selinux' relabel='yes'/>
</domain>

3.  Start testpmd forward inside guest
Install dpdk rpms inside guest
Configure hugepage inside guest
bind the two port to dpdk inside guest.
modprobe vfio-pci
dpdk-devbind -b vfio-pci 03:00.0 04:00.0
Start testpmd inside guest:
testpmd -l 0,1,2 -n 4 --socket-mem 1024,1024 --legacy-mem -- --burst=64 -i --rxd=512 --txd=512 --nb-cores=2 --txq=1 --rxq=1 --max-pkt-len=2000

Actual results:
Run testpmd command with "--max-pkt-len=2000" failed inside guest.
Testpmd can run successfully without "--max-pkt-len=2000" inside guest. 
Testpmd can run successfully with "--max-pkt-len=2000"on host.

[root@localhost ~]# uname -a
Linux localhost.localdomain 4.18.0-56.el8.x86_64 #1 SMP Mon Dec 17 13:56:22 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

[root@netqe22 ~]# virsh console master
Connected to domain master
Escape character is ^]

Red Hat Enterprise Linux 8.0 Beta (Ootpa)
Kernel 4.18.0-56.el8.x86_64 on an x86_64

Activate the web console with: systemctl enable --now cockpit.socket

localhost login: root
Password:
Last login: Thu Jan 24 03:22:37 on ttyS0
[root@localhost ~]# /root/one_gig_hugepages.sh 1
dpdk-devbind -b vfio-pci 03:00.0 04:0++ echo 1
0.0[root@localhost ~
[root@localhost ~]#
rst=64 -i --rxd=512 --txd=512 --nb-cores=2 --txq=1 --rxq=1 --max-pkt-len=2000-bur
EAL: Detected 3 lcore(s)
EAL: Detected 1 NUMA nodes
EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
EAL: Probing VFIO support...
EAL: VFIO support initialized
EAL: WARNING: cpu flags constant_tsc=yes nonstop_tsc=no -> using unreliable clock cycles !
EAL: PCI device 0000:02:00.0 on NUMA socket -1
EAL:   Invalid NUMA socket, default to 0
EAL:   probe driver: 1af4:1041 net_virtio
EAL: Error: Invalid memory
EAL: PCI device 0000:03:00.0 on NUMA socket -1
EAL:   Invalid NUMA socket, default to 0
EAL:   probe driver: 1af4:1041 net_virtio
EAL:   using IOMMU type 1 (Type 1)
EAL: PCI device 0000:04:00.0 on NUMA socket -1
EAL:   Invalid NUMA socket, default to 0
EAL:   probe driver: 1af4:1041 net_virtio
Interactive-mode selected
testpmd: create a new mbuf pool <mbuf_pool_socket_0>: n=163456, size=2176, socket=0
testpmd: preferred mempool ops selected: ring_mp_mc
Configuring Port 0 (socket 0)
Ethdev port_id=0 requested Rx offloads 0x800 doesn't match Rx offloads capabilities 0x21d in rte_eth_dev_configure()
Fail to configure port 0
EAL: Error - exiting with code: 1
  Cause: Start ports failed


Expected results:
Testpmd can run successfully with "--max-pkt-len=2000" inside guest

Additional info: