diff --git a/test_plans/vswitch_sample_cbdma_test_plan.rst b/test_plans/vswitch_sample_cbdma_test_plan.rst
index af2e62d1..679e3ee8 100644
--- a/test_plans/vswitch_sample_cbdma_test_plan.rst
+++ b/test_plans/vswitch_sample_cbdma_test_plan.rst
@@ -37,68 +37,140 @@ Vswitch sample test with vhost async data path test plan
 Description
 ===========
 
-Vswitch sample can leverage IOAT to accelerate vhost async data-path from dpdk 20.11. This plan test
-vhost DMA operation callbacks for CBDMA PMD and vhost async data-path in vhost sample.
+Vswitch sample can leverage IOAT to accelerate vhost async data-path from dpdk 20.11.
+This plan test vhost DMA operation callbacks for CBDMA PMD and vhost async data-path in vhost sample.
 From 20.11 to 21.02, only split ring support cbdma copy with vhost enqueue direction;
 from 21.05,packed ring also can support cbdma copy with vhost enqueue direction.
 
+For more about dpdk-testpmd sample, please refer to the DPDK docments:
+https://doc.dpdk.org/guides/testpmd_app_ug/run_app.html
+
+For virtio-user vdev parameter, you can refer to the DPDK docments:
+https://doc.dpdk.org/guides/nics/virtio.html#virtio-paths-selection-and-usage.
+
+For more about dpdk-vhost sample, please refer to the DPDK docments:
+https://doc.dpdk.org/guides/sample_app_ug/vhost.html
+
 Prerequisites
 =============
 
+Topology
+--------
+      Test flow: TG-->NIC-->VSwitch-->Virtio-->VSwitch-->NIC-->TG
+
+Hardware
+--------
+      Supportted NICs: ALL
+
+Software
+--------
+      Trex:http://trex-tgn.cisco.com/trex/release/v2.26.tar.gz
+
+General set up
+--------------
+1. Compile DPDK::
+
+      # CC=gcc meson --werror -Denable_kmods=True -Dlibdir=lib -Dexamples=all --default-library=<dpdk build dir>
+      # ninja -C <dpdk build dir> -j 110
+
+2. Get the PCI device ID and DMA device ID of DUT, for example, 0000:18:00.0 is PCI device ID, 0000:00:04.0, 0000:00:04.1 is DMA device ID::
+
+      <dpdk dir># ./usertools/dpdk-devbind.py -s
+
+      Network devices using kernel driver
+      ===================================
+      0000:18:00.0 'Device 159b' if=ens785f0 drv=ice unused=vfio-pci
+
+      DMA devices using kernel driver
+      ===============================
+      0000:00:04.0 'Sky Lake-E CBDMA Registers 2021' drv=ioatdma unused=vfio-pci
+      0000:00:04.1 'Sky Lake-E CBDMA Registers 2021' drv=ioatdma unused=vfio-pci
+
+Test case
+=========
+
+Common steps
+------------
+1. Bind 1 NIC port and CBDMA channels to vfio-pci::
+
+      <dpdk dir># ./usertools/dpdk-devbind.py -b vfio-pci <DUT port pci device id>
+      <dpdk dir># ./usertools/dpdk-devbind.py -b vfio-pci <DUT port DMA device id>
+
+      For example, Bind 1 NIC port and 2 CBDMA channels::
+      ./usertools/dpdk-devbind.py -b vfio-pci 0000:00:18.0
+      ./usertools/dpdk-devbind.py -b vfio-pci 0000:00:04.0,0000:00:04.1
+
+2. Inject imix packets to NIC by traffic generator::
+
+      The packet size include [64, 128, 256, 512, 1024, 1518], and the format of packet is as follows.
+      +-------------+-------------+-------------+-------------+
+      | MAC         | MAC         | IPV4        | IPV4        |
+      | Src address | Dst address | Src address | Dst address |
+      |-------------|-------------|-------------|-------------|
+      | Any MAC     | Virtio mac  | Any IP      | Any IP      |
+      +-------------+-------------+-------------+-------------+
+      All the packets in this test plan use the Virtio mac:00:11:22:33:44:10.
 
 Test Case1: PVP performance check with CBDMA channel using vhost async driver
-=============================================================================
+-----------------------------------------------------------------------------
+This case uses vhost, testpmd and Traffic Generator(For example, Trex) to test performance with 1 CBDMA channel using vhost async driver.
 
-1. Bind physical port to vfio-pci and CBDMA channel to vfio-pci.
+1. Bind 1 NIC port and 1 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-	./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 31-32 -n 4 -- \
-	-p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat --stats 1 --socket-file /tmp/vhost-net --dmas [txd0@0000:00:04.0] --client --total-num-mbufs 600000
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 31-32 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+	--stats 1 --socket-file /tmp/vhost-net --dmas [txd0@0000:00:04.0] --client --total-num-mbufs 600000
 
 3. Launch virtio-user with packed ring::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 --force-max-simd-bitwidth=512 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,packed_vq=1,server=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 --force-max-simd-bitwidth=512 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,packed_vq=1,server=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 
 4. Start pkts from virtio-user side to let vswitch know the mac addr::
 
 	testpmd>set fwd mac
 	testpmd>start tx_first
 
-5. Inject pkts (packets length=64...1518) separately with dest_mac=virtio_mac_address (specific in above cmd with 00:11:22:33:44:10) to NIC using packet generator, record pvp (PG>nic>vswitch>virtio-user>vswitch>nic>PG) performance number can get expected.
+5. Send imix packets [64,1518] from packet generator as common step2, and check the throughput can get expected data.
 
 6. Quit and re-launch virtio-user with packed ring size not power of 2::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 --force-max-simd-bitwidth=512 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,packed_vq=1,server=1,queue_size=1025 -- -i --rxq=1 --txq=1 --txd=1025 --rxd=1025 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 --force-max-simd-bitwidth=512 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,packed_vq=1,server=1,queue_size=1025 \
+	-- -i --rxq=1 --txq=1 --txd=1025 --rxd=1025 --nb-cores=1
 
 7. Re-test step 4-5, record performance of different packet length.
 
 8. Quit and re-launch virtio-user with split ring::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,server=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net,queues=1,mrg_rxbuf=0,in_order=1,vectorized=1,server=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 
 9. Re-test step 4-5, record performance of different packet length.
 
 Test Case2: PVP test with two VM and two CBDMA channels using vhost async driver
-=================================================================================
+--------------------------------------------------------------------------------
+This case uses vhost, testpmd and Traffic Generator(For example, Trex) to test 2 VMs performance with 2 CBDMA channels using vhost async driver.
 
-1. Bind one physical ports to vfio-pci and two CBDMA channels to vfio-pci.
+1. Bind 1 NIC port and 2 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-	./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- \
-	-p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat --stats 1 --socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:01.0,txd1@0000:00:01.1] --client--total-num-mbufs 600000
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+	--stats 1 --socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:01.0,txd1@0000:00:01.1] --client--total-num-mbufs 600000
 
 3. launch two virtio-user ports::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net0,queues=1,server=1,mrg_rxbuf=1,in_order=0,packed_vq=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net0,queues=1,server=1,mrg_rxbuf=1,in_order=0,packed_vq=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 	
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 31-32 -n 4 --no-pci --file-prefix=testpmd1 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:11,path=/tmp/vhost-net1,queues=1,server=1,mrg_rxbuf=1,in_order=1,vectorized=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 31-32 -n 4 --no-pci --file-prefix=testpmd1 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:11,path=/tmp/vhost-net1,queues=1,server=1,mrg_rxbuf=1,in_order=1,vectorized=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 
 4. Start pkts from two virtio-user side individually to let vswitch know the mac addr::
 
@@ -107,7 +179,7 @@ Test Case2: PVP test with two VM and two CBDMA channels using vhost async driver
 	testpmd1>start tx_first
 	testpmd1>start tx_first
 
-5. Inject IMIX packets (64b...1518b) with dest_mac=virtio_mac_address (00:11:22:33:44:10 and 00:11:22:33:44:11) to NIC using packet generator,record performance number can get expected from Packet generator rx side.
+5. Send imix packets [64,1518] from packet generator as common step2, and check the throughput can get expected data.
 
 6. Stop dpdk-vhost side and relaunch it with same cmd as step2.
 
@@ -121,22 +193,25 @@ Test Case2: PVP test with two VM and two CBDMA channels using vhost async driver
 8. Inject IMIX packets (64b...1518b) with dest_mac=virtio_mac_address (00:11:22:33:44:10 and 00:11:22:33:44:11) to NIC using packet generator, ensure get same throughput as step5.
 
 Test Case3: VM2VM forwarding test with two CBDMA channels
-=========================================================
+---------------------------------------------------------
+This case uses vhost, testpmd  to test vm to vm forwarding packets with 2 CBDMA channels.
 
-1.Bind one physical ports to vfio-pci and two CBDMA channels to vfio-pci.
+1. Bind 1 NIC port and 2 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-	./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
 	--socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:04.0,txd1@0000:00:04.1]  --client --total-num-mbufs 600000
 
 3. Launch virtio-user::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net0,queues=1,server=1,mrg_rxbuf=1,in_order=0,packed_vq=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 29-30 -n 4 --no-pci --file-prefix=testpmd0 \
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:10,path=/tmp/vhost-net0,queues=1,server=1,mrg_rxbuf=1,in_order=0,packed_vq=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 
 	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 31-32 -n 4 --no-pci --file-prefix=testpmd1 \
-	--vdev=net_virtio_user0,mac=00:11:22:33:44:11,path=/tmp/vhost-net1,queues=1,server=1,mrg_rxbuf=1,in_order=1,vectorized=1 -- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
+	--vdev=net_virtio_user0,mac=00:11:22:33:44:11,path=/tmp/vhost-net1,queues=1,server=1,mrg_rxbuf=1,in_order=1,vectorized=1 \
+	-- -i --rxq=1 --txq=1 --txd=1024 --rxd=1024 --nb-cores=1
 
 4. Loop pkts between two virtio-user sides, record performance number with 64b/2000b/8000b/IMIX pkts can get expected::
 
@@ -168,13 +243,14 @@ Test Case3: VM2VM forwarding test with two CBDMA channels
 6. Rerun step 4.
 
 Test Case4: VM2VM test with cbdma channels register/unregister stable check
-============================================================================
+---------------------------------------------------------------------------
+This case uses vhost, qemu to test vm to vm forwarding packets with 2 CBDMA channels stable when re-bind PCI in vms 50 times.
 
-1. Bind one physical ports to vfio-pci and two CBDMA channels to vfio-pci.
+1. Bind 1 NIC port and 2 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-    ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+    <dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
     --socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:04.0,txd1@0000:00:04.1] --client --total-num-mbufs 600000
 
 3. Start VM0 with qemu-5.2.0::
@@ -188,7 +264,8 @@ Test Case4: VM2VM test with cbdma channels register/unregister stable check
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6002-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net0,server \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=on,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :10
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=on,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :10
 
 4. Start VM1 with qemu-5.2.0::
 
@@ -201,7 +278,8 @@ Test Case4: VM2VM test with cbdma channels register/unregister stable check
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6003-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net1,server \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=on,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :12
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=on,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :12
 
 5. Bind virtio port to vfio-pci in both two VMs::
 
@@ -212,7 +290,7 @@ Test Case4: VM2VM test with cbdma channels register/unregister stable check
 
 6. Start testpmd in VMs seperately::
 
-	./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 1-2 -n 4 -- -i --rxq=1 --txq=1 --nb-cores=1 --txd=1024 --rxd=1024
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/app/dpdk-testpmd -l 1-2 -n 4 -- -i --rxq=1 --txq=1 --nb-cores=1 --txd=1024 --rxd=1024
 
 7. Loop pkts between two virtio-user sides, record performance number with 64b/2000b/8000b/IMIX pkts can get expected::
 
@@ -248,13 +326,14 @@ Test Case4: VM2VM test with cbdma channels register/unregister stable check
 9. Restart vhost, then rerun step 7，check vhost can stable work and get expected throughput.
 
 Test Case5: VM2VM split ring test with iperf and reconnect stable check
-=======================================================================
+-----------------------------------------------------------------------
+This case uses vhost, testpmd  to test split ring path vm to vm iperf and reconnect stable with 2 CBDMA channels.
 
-1. Bind one physical ports to vfio-pci and two CBDMA channels to vfio-pci.
+1. Bind 1 NIC port and 2 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-	./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
 	--socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:04.0,txd1@0000:00:04.1] --client --total-num-mbufs 600000
 
 3. Start VM0 with qemu-5.2.0::
@@ -268,7 +347,8 @@ Test Case5: VM2VM split ring test with iperf and reconnect stable check
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6002-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net0,server \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=off,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :10
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=off,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :10
 
 4. Start VM1 with qemu-5.2.0::
 
@@ -281,7 +361,8 @@ Test Case5: VM2VM split ring test with iperf and reconnect stable check
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6003-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net1,server \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=off,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :12
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=off,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on -vnc :12
 
 5. On VM1, set virtio device IP and run arp protocal::
 
@@ -307,13 +388,14 @@ Test Case5: VM2VM split ring test with iperf and reconnect stable check
 10. Relaunch vhost-dpdk, then rerun step 7-9 five times.
 
 Test Case6: VM2VM packed ring test with iperf and reconnect stable test
-=======================================================================
+-----------------------------------------------------------------------
+This case uses vhost, testpmd  to test packed ring path vm to vm iperf and reconnect stable with 2 CBDMA channels.
 
-1. Bind one physical ports to vfio-pci and two CBDMA channels to vfio-pci.
+1. Bind 1 NIC port and 2 CBDMA channel to vfio-pci, as common step 1.
 
 2. On host, launch dpdk-vhost by below command::
 
-	./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
+	<dpdk dir># ./x86_64-native-linuxapp-gcc/examples/dpdk-vhost -l 26-28 -n 4 -- -p 0x1 --mergeable 1 --vm2vm 1 --dma-type ioat \
 	--socket-file /tmp/vhost-net0 --socket-file /tmp/vhost-net1 --dmas [txd0@0000:00:04.0,txd1@0000:00:04.1] --total-num-mbufs 600000
 
 3. Start VM0 with qemu-5.2.0::
@@ -327,7 +409,8 @@ Test Case6: VM2VM packed ring test with iperf and reconnect stable test
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6002-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net0 \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=off,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :10
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:01,disable-modern=true,mrg_rxbuf=off,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :10
 
 4. Start VM1 with qemu-5.2.0::
 
@@ -340,7 +423,8 @@ Test Case6: VM2VM packed ring test with iperf and reconnect stable test
         -netdev user,id=nttsip1,hostfwd=tcp:127.0.0.1:6003-:22 \
         -chardev socket,id=char0,path=/tmp/vhost-net1 \
         -netdev type=vhost-user,id=netdev0,chardev=char0,vhostforce \
-        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=off,csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :12
+        -device virtio-net-pci,netdev=netdev0,mac=52:54:00:00:00:02,disable-modern=true,mrg_rxbuf=off,\
+        csum=on,guest_csum=on,host_tso4=on,guest_tso4=on,guest_ecn=on,packed=on -vnc :12
 
 5. On VM1, set virtio device IP and run arp protocal::
 
