1.\"- 2.\" SPDX-License-Identifier: BSD-3-Clause 3.\" 4.\" Copyright (c) 2026 Kevin Bowling <kbowling@FreeBSD.org> 5.\" All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the copyright holder nor the names of its 16.\" contributors may be used to endorse or promote products derived from 17.\" this software without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 20.\" "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 21.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 22.\" A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 23.\" OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 24.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 25.\" TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 26.\" PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 27.\" LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 28.\" NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 29.\" SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd September 14, 2026 32.Dt IXV 4 33.Os 34.Sh NAME 35.Nm ixv 36.Nd Intel Ethernet virtual function driver 37.Sh SYNOPSIS 38To compile this driver into the kernel, 39place the following lines in the kernel configuration file: 40.Bd -ragged -offset indent 41.Cd "device iflib" 42.Cd "device ixv" 43.Ed 44.Pp 45Alternatively, to load the driver as a module at boot time, 46place the following line in 47.Xr loader.conf 5 : 48.Bd -literal -offset indent 49if_ixv_load="YES" 50.Ed 51.Sh DESCRIPTION 52The 53.Nm 54driver provides support for PCI Express virtual functions exposed by 55supported Intel Ethernet controllers. 56The physical function must create and configure the virtual function before 57it can be attached on the host or assigned to a 58.Fx 59guest. 60.Pp 61The driver supports jumbo frames, MSI-X, receive-side scaling, 62TCP segmentation offload, checksum offload, and VLAN hardware offload. 63The maximum supported MTU is 9710 bytes, except that an 82599 VF on 64Hyper-V is limited to 1504 bytes. 65.Pp 66The physical-function driver controls the resources and policy presented to 67the virtual function. 68The number of available queue pairs is negotiated with the physical function 69where the mailbox protocol supports it, and is also limited by the available 70MSI-X vectors. 71Requests to change the MAC address, VLAN membership, or receive mode may be 72rejected by physical-function policy. 73.Pp 74On Hyper-V, the host provides reset and assigned-address information through 75PCI configuration space instead of the Intel PF/VF mailbox. 76The driver uses up to two queue pairs on X550, X552, X553, and E610 77when the host advertises multiple queues through PCI configuration space 78and sufficient MSI-X vectors are available. 79Otherwise, it uses one queue pair. 80To request two queue pairs, run the following from an elevated PowerShell 81prompt on the Hyper-V host, substituting the VM and network adapter names: 82.Bd -literal -offset indent 83Set-VMNetworkAdapter -VMName "vm-name" -Name "adapter-name" ` 84 -IovQueuePairsRequested 2 85.Ed 86.Pp 87Changing this setting can detach and reattach the VF, so configure it before 88starting the guest when possible. 89.Pp 90MAC address, VLAN, multicast filter, and receive mode policies remain under 91host control. 92On E610, when the host does not support the PCI link-status query, 93the driver uses the virtual-function carrier indication and reports an 94unknown link speed. 95.Pp 96The virtual function cannot configure the physical media. 97Only automatic media selection is supported, and reported link state and 98speed are supplied by the physical function or virtual-function hardware. 99.Sh HARDWARE 100The 101.Nm 102driver supports virtual functions from the following Intel controller 103families: 104.Pp 105.Bl -bullet -compact 106.It 107Ethernet E610 108.It 109Ethernet X550, X552, and X553 110.It 111Ethernet X540 112.It 113Ethernet 82599 114.El 115.Sh SEE ALSO 116.Xr iflib 4 , 117.Xr ix 4 , 118.Xr pci 4 , 119.Xr iovctl.conf 5 , 120.Xr loader.conf 5 , 121.Xr ifconfig 8 122