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+Hyper-V network driver
+======================
+
+Compatibility
+=============
+
+This driver is compatible with Windows Server 2012 R2, 2016 and
+Windows 10.
+
+Features
+========
+
+ Checksum offload
+ ----------------
+ The netvsc driver supports checksum offload as long as the
+ Hyper-V host version does. Windows Server 2016 and Azure
+ support checksum offload for TCP and UDP for both IPv4 and
+ IPv6. Windows Server 2012 only supports checksum offload for TCP.
+
+ Receive Side Scaling
+ --------------------
+ Hyper-V supports receive side scaling. For TCP & UDP, packets can
+ be distributed among available queues based on IP address and port
+ number.
+
+ For TCP & UDP, we can switch hash level between L3 and L4 by ethtool
+ command. TCP/UDP over IPv4 and v6 can be set differently. The default
+ hash level is L4. We currently only allow switching TX hash level
+ from within the guests.
+
+ On Azure, fragmented UDP packets have high loss rate with L4
+ hashing. Using L3 hashing is recommended in this case.
+
+ For example, for UDP over IPv4 on eth0:
+ To include UDP port numbers in hashing:
+ ethtool -N eth0 rx-flow-hash udp4 sdfn
+ To exclude UDP port numbers in hashing:
+ ethtool -N eth0 rx-flow-hash udp4 sd
+ To show UDP hash level:
+ ethtool -n eth0 rx-flow-hash udp4
+
+ Generic Receive Offload, aka GRO
+ --------------------------------
+ The driver supports GRO and it is enabled by default. GRO coalesces
+ like packets and significantly reduces CPU usage under heavy Rx
+ load.
+
+ Large Receive Offload (LRO), or Receive Side Coalescing (RSC)
+ -------------------------------------------------------------
+ The driver supports LRO/RSC in the vSwitch feature. It reduces the per packet
+ processing overhead by coalescing multiple TCP segments when possible. The
+ feature is enabled by default on VMs running on Windows Server 2019 and
+ later. It may be changed by ethtool command:
+ ethtool -K eth0 lro on
+ ethtool -K eth0 lro off
+
+ SR-IOV support
+ --------------
+ Hyper-V supports SR-IOV as a hardware acceleration option. If SR-IOV
+ is enabled in both the vSwitch and the guest configuration, then the
+ Virtual Function (VF) device is passed to the guest as a PCI
+ device. In this case, both a synthetic (netvsc) and VF device are
+ visible in the guest OS and both NIC's have the same MAC address.
+
+ The VF is enslaved by netvsc device. The netvsc driver will transparently
+ switch the data path to the VF when it is available and up.
+ Network state (addresses, firewall, etc) should be applied only to the
+ netvsc device; the slave device should not be accessed directly in
+ most cases. The exceptions are if some special queue discipline or
+ flow direction is desired, these should be applied directly to the
+ VF slave device.
+
+ Receive Buffer
+ --------------
+ Packets are received into a receive area which is created when device
+ is probed. The receive area is broken into MTU sized chunks and each may
+ contain one or more packets. The number of receive sections may be changed
+ via ethtool Rx ring parameters.
+
+ There is a similar send buffer which is used to aggregate packets for sending.
+ The send area is broken into chunks of 6144 bytes, each of section may
+ contain one or more packets. The send buffer is an optimization, the driver
+ will use slower method to handle very large packets or if the send buffer
+ area is exhausted.